diff options
23 files changed, 2335 insertions, 70 deletions
diff --git a/Documentation/ABI/testing/debugfs-wilco-ec b/Documentation/ABI/testing/debugfs-wilco-ec index 73a5a66ddca6..9d8d9d2def5b 100644 --- a/Documentation/ABI/testing/debugfs-wilco-ec +++ b/Documentation/ABI/testing/debugfs-wilco-ec @@ -23,11 +23,9 @@ Description: For writing, bytes 0-1 indicate the message type, one of enum wilco_ec_msg_type. Byte 2+ consist of the data passed in the - request, starting at MBOX[0] - - At least three bytes are required for writing, two for the type - and at least a single byte of data. Only the first - EC_MAILBOX_DATA_SIZE bytes of MBOX will be used. + request, starting at MBOX[0]. At least three bytes are required + for writing, two for the type and at least a single byte of + data. Example: // Request EC info type 3 (EC firmware build date) @@ -40,7 +38,7 @@ Description: $ cat /sys/kernel/debug/wilco_ec/raw 00 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 ..12/21/18.8... - Note that the first 32 bytes of the received MBOX[] will be - printed, even if some of the data is junk. It is up to you to - know how many of the first bytes of data are the actual - response. + Note that the first 16 bytes of the received MBOX[] will be + printed, even if some of the data is junk, and skipping bytes + 17 to 32. It is up to you to know how many of the first bytes of + data are the actual response. diff --git a/Documentation/ABI/testing/sysfs-platform-wilco-ec b/Documentation/ABI/testing/sysfs-platform-wilco-ec new file mode 100644 index 000000000000..8827a734f933 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform-wilco-ec @@ -0,0 +1,40 @@ +What: /sys/bus/platform/devices/GOOG000C\:00/boot_on_ac +Date: April 2019 +KernelVersion: 5.3 +Description: + Boot on AC is a policy which makes the device boot from S5 + when AC power is connected. This is useful for users who + want to run their device headless or with a dock. + + Input should be parseable by kstrtou8() to 0 or 1. + +What: /sys/bus/platform/devices/GOOG000C\:00/build_date +Date: May 2019 +KernelVersion: 5.3 +Description: + Display Wilco Embedded Controller firmware build date. + Output will a MM/DD/YY string. + +What: /sys/bus/platform/devices/GOOG000C\:00/build_revision +Date: May 2019 +KernelVersion: 5.3 +Description: + Display Wilco Embedded Controller build revision. + Output will a version string be similar to the example below: + d2592cae0 + +What: /sys/bus/platform/devices/GOOG000C\:00/model_number +Date: May 2019 +KernelVersion: 5.3 +Description: + Display Wilco Embedded Controller model number. + Output will a version string be similar to the example below: + 08B6 + +What: /sys/bus/platform/devices/GOOG000C\:00/version +Date: May 2019 +KernelVersion: 5.3 +Description: + Display Wilco Embedded Controller firmware version. + The format of the string is x.y.z. Where x is major, y is minor + and z is the build number. For example: 95.00.06 diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig index 997317d2f2b9..0b3c2b9ffd2f 100644 --- a/drivers/platform/chrome/Kconfig +++ b/drivers/platform/chrome/Kconfig @@ -71,6 +71,19 @@ config CROS_EC_RPMSG To compile this driver as a module, choose M here: the module will be called cros_ec_rpmsg. +config CROS_EC_ISHTP + tristate "ChromeOS Embedded Controller (ISHTP)" + depends on MFD_CROS_EC + depends on INTEL_ISH_HID + help + If you say Y here, you get support for talking to the ChromeOS EC + firmware running on Intel Integrated Sensor Hub (ISH), using the + ISH Transport protocol (ISH-TP). This uses a simple byte-level + protocol with a checksum. + + To compile this driver as a module, choose M here: the + module will be called cros_ec_ishtp. + config CROS_EC_SPI tristate "ChromeOS Embedded Controller (SPI)" depends on MFD_CROS_EC && SPI diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile index 1b2f1dcfcd5c..c5583c48d1e5 100644 --- a/drivers/platform/chrome/Makefile +++ b/drivers/platform/chrome/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o obj-$(CONFIG_CHROMEOS_PSTORE) += chromeos_pstore.o obj-$(CONFIG_CHROMEOS_TBMC) += chromeos_tbmc.o obj-$(CONFIG_CROS_EC_I2C) += cros_ec_i2c.o +obj-$(CONFIG_CROS_EC_ISHTP) += cros_ec_ishtp.o obj-$(CONFIG_CROS_EC_RPMSG) += cros_ec_rpmsg.o obj-$(CONFIG_CROS_EC_SPI) += cros_ec_spi.o cros_ec_lpcs-objs := cros_ec_lpc.o cros_ec_lpc_reg.o diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c index 4c2a27f6a6d0..4578eb3e0731 100644 --- a/drivers/platform/chrome/cros_ec_debugfs.c +++ b/drivers/platform/chrome/cros_ec_debugfs.c @@ -241,7 +241,7 @@ static ssize_t cros_ec_pdinfo_read(struct file *file, read_buf, p - read_buf); } -const struct file_operations cros_ec_console_log_fops = { +static const struct file_operations cros_ec_console_log_fops = { .owner = THIS_MODULE, .open = cros_ec_console_log_open, .read = cros_ec_console_log_read, @@ -250,7 +250,7 @@ const struct file_operations cros_ec_console_log_fops = { .release = cros_ec_console_log_release, }; -const struct file_operations cros_ec_pdinfo_fops = { +static const struct file_operations cros_ec_pdinfo_fops = { .owner = THIS_MODULE, .open = simple_open, .read = cros_ec_pdinfo_read, diff --git a/drivers/platform/chrome/cros_ec_ishtp.c b/drivers/platform/chrome/cros_ec_ishtp.c new file mode 100644 index 000000000000..e504d255d5ce --- /dev/null +++ b/drivers/platform/chrome/cros_ec_ishtp.c @@ -0,0 +1,763 @@ +// SPDX-License-Identifier: GPL-2.0 +// ISHTP interface for ChromeOS Embedded Controller +// +// Copyright (c) 2019, Intel Corporation. +// +// ISHTP client driver for talking to the Chrome OS EC firmware running +// on Intel Integrated Sensor Hub (ISH) using the ISH Transport protocol +// (ISH-TP). + +#include <linux/delay.h> +#include <linux/mfd/core.h> +#include <linux/mfd/cros_ec.h> +#include <linux/mfd/cros_ec_commands.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/intel-ish-client-if.h> + +/* + * ISH TX/RX ring buffer pool size + * + * The AP->ISH messages and corresponding ISH->AP responses are + * serialized. We need 1 TX and 1 RX buffer for these. + * + * The MKBP ISH->AP events are serialized. We need one additional RX + * buffer for them. + */ +#define CROS_ISH_CL_TX_RING_SIZE 8 +#define CROS_ISH_CL_RX_RING_SIZE 8 + +/* ISH CrOS EC Host Commands */ +enum cros_ec_ish_channel { + CROS_EC_COMMAND = 1, /* AP->ISH message */ + CROS_MKBP_EVENT = 2, /* ISH->AP events */ +}; + +/* + * ISH firmware timeout for 1 message send failure is 1Hz, and the + * firmware will retry 2 times, so 3Hz is used for timeout. + */ +#define ISHTP_SEND_TIMEOUT (3 * HZ) + +/* ISH Transport CrOS EC ISH client unique GUID */ +static const guid_t cros_ish_guid = + GUID_INIT(0x7b7154d0, 0x56f4, 0x4bdc, + 0xb0, 0xd8, 0x9e, 0x7c, 0xda, 0xe0, 0xd6, 0xa0); + +struct header { + u8 channel; + u8 status; + u8 reserved[2]; +} __packed; + +struct cros_ish_out_msg { + struct header hdr; + struct ec_host_request ec_request; +} __packed; + +struct cros_ish_in_msg { + struct header hdr; + struct ec_host_response ec_response; +} __packed; + +#define IN_MSG_EC_RESPONSE_PREAMBLE \ + offsetof(struct cros_ish_in_msg, ec_response) + +#define OUT_MSG_EC_REQUEST_PREAMBLE \ + offsetof(struct cros_ish_out_msg, ec_request) + +#define cl_data_to_dev(client_data) ishtp_device((client_data)->cl_device) + +/* + * The Read-Write Semaphore is used to prevent message TX or RX while + * the ishtp client is being initialized or undergoing reset. + * + * The readers are the kernel function calls responsible for IA->ISH + * and ISH->AP messaging. + * + * The writers are .reset() and .probe() function. + */ +DECLARE_RWSEM(init_lock); + +/** + * struct response_info - Encapsulate firmware response related + * information for passing between function ish_send() and + * process_recv() callback. + * + * @data: Copy the data received from firmware here. + * @max_size: Max size allocated for the @data buffer. If the received + * data exceeds this value, we log an error. + * @size: Actual size of data received from firmware. + * @error: 0 for success, negative error code for a failure in process_recv(). + * @received: Set to true on receiving a valid firmware response to host command + * @wait_queue: Wait queue for host to wait for firmware response. + */ +struct response_info { + void *data; + size_t max_size; + size_t size; + int error; + bool received; + wait_queue_head_t wait_queue; +}; + +/** + * struct ishtp_cl_data - Encapsulate per ISH TP Client. + * + * @cros_ish_cl: ISHTP firmware client instance. + * @cl_device: ISHTP client device instance. + * @response: Response info passing between ish_send() and process_recv(). + * @work_ishtp_reset: Work queue reset handling. + * @work_ec_evt: Work queue for EC events. + * @ec_dev: CrOS EC MFD device. + * + * This structure is used to store per client data. + */ +struct ishtp_cl_data { + struct ishtp_cl *cros_ish_cl; + struct ishtp_cl_device *cl_device; + + /* + * Used for passing firmware response information between + * ish_send() and process_recv() callback. + */ + struct response_info response; + + struct work_struct work_ishtp_reset; + struct work_struct work_ec_evt; + struct cros_ec_device *ec_dev; +}; + +/** + * ish_evt_handler - ISH to AP event handler + * @work: Work struct + */ +static void ish_evt_handler(struct work_struct *work) +{ + struct ishtp_cl_data *client_data = + container_of(work, struct ishtp_cl_data, work_ec_evt); + struct cros_ec_device *ec_dev = client_data->ec_dev; + + if (cros_ec_get_next_event(ec_dev, NULL) > 0) { + blocking_notifier_call_chain(&ec_dev->event_notifier, + 0, ec_dev); + } +} + +/** + * ish_send() - Send message from host to firmware + * + * @client_data: Client data instance + * @out_msg: Message buffer to be sent to firmware + * @out_size: Size of out going message + * @in_msg: Message buffer where the incoming data is copied. This buffer + * is allocated by calling + * @in_size: Max size of incoming message + * + * Return: Number of bytes copied in the in_msg on success, negative + * error code on failure. + */ +static int ish_send(struct ishtp_cl_data *client_data, + u8 *out_msg, size_t out_size, + u8 *in_msg, size_t in_size) +{ + int rv; + struct header *out_hdr = (struct header *)out_msg; + struct ishtp_cl *cros_ish_cl = client_data->cros_ish_cl; + + dev_dbg(cl_data_to_dev(client_data), + "%s: channel=%02u status=%02u\n", + __func__, out_hdr->channel, out_hdr->status); + + /* Setup for incoming response */ + client_data->response.data = in_msg; + client_data->response.max_size = in_size; + client_data->response.error = 0; + client_data->response.received = false; + + rv = ishtp_cl_send(cros_ish_cl, out_msg, out_size); + if (rv) { + dev_err(cl_data_to_dev(client_data), + "ishtp_cl_send error %d\n", rv); + return rv; + } + + wait_event_interruptible_timeout(client_data->response.wait_queue, + client_data->response.received, + ISHTP_SEND_TIMEOUT); + if (!client_data->response.received) { + dev_err(cl_data_to_dev(client_data), + "Timed out for response to host message\n"); + return -ETIMEDOUT; + } + + if (client_data->response.error < 0) + return client_data->response.error; + + return client_data->response.size; +} + +/** + * process_recv() - Received and parse incoming packet + * @cros_ish_cl: Client instance to get stats + * @rb_in_proc: Host interface message buffer + * + * Parse the incoming packet. If it is a response packet then it will + * update per instance flags and wake up the caller waiting to for the + * response. If it is an event packet then it will schedule event work. + */ +static void process_recv(struct ishtp_cl *cros_ish_cl, + struct ishtp_cl_rb *rb_in_proc) +{ + size_t data_len = rb_in_proc->buf_idx; + struct ishtp_cl_data *client_data = + ishtp_get_client_data(cros_ish_cl); + struct device *dev = cl_data_to_dev(client_data); + struct cros_ish_in_msg *in_msg = + (struct cros_ish_in_msg *)rb_in_proc->buffer.data; + + /* Proceed only if reset or init is not in progress */ + if (!down_read_trylock(&init_lock)) { + /* Free the buffer */ + ishtp_cl_io_rb_recycle(rb_in_proc); + dev_warn(dev, + "Host is not ready to receive incoming messages\n"); + return; + } + + /* + * All firmware messages contain a header. Check the buffer size + * before accessing elements inside. + */ + if (!rb_in_proc->buffer.data) { + dev_warn(dev, "rb_in_proc->buffer.data returned null"); + client_data->response.error = -EBADMSG; + goto end_error; + } + + if (data_len < sizeof(struct header)) { + dev_err(dev, "data size %zu is less than header %zu\n", + data_len, sizeof(struct header)); + client_data->response.error = -EMSGSIZE; + goto end_error; + } + + dev_dbg(dev, "channel=%02u status=%02u\n", + in_msg->hdr.channel, in_msg->hdr.status); + + switch (in_msg->hdr.channel) { + case CROS_EC_COMMAND: + /* Sanity check */ + if (!client_data->response.data) { + dev_err(dev, + "Receiving buffer is null. Should be allocated by calling function\n"); + client_data->response.error = -EINVAL; + goto error_wake_up; + } + + if (client_data->response.received) { + dev_err(dev, + "Previous firmware message not yet processed\n"); + client_data->response.error = -EINVAL; + goto error_wake_up; + } + + if (data_len > client_data->response.max_size) { + dev_err(dev, + "Received buffer size %zu is larger than allocated buffer %zu\n", + data_len, client_data->response.max_size); + client_data->response.error = -EMSGSIZE; + goto error_wake_up; + } + + if (in_msg->hdr.status) { + dev_err(dev, "firmware returned status %d\n", + in_msg->hdr.status); + client_data->response.error = -EIO; + goto error_wake_up; + } + + /* Update the actual received buffer size */ + client_data->response.size = data_len; + + /* + * Copy the buffer received in firmware response for the + * calling thread. + */ + memcpy(client_data->response.data, + rb_in_proc->buffer.data, data_len); + + /* Set flag before waking up the caller */ + client_data->response.received = true; +error_wake_up: + /* Wake the calling thread */ + wake_up_interruptible(&client_data->response.wait_queue); + + break; + + case CROS_MKBP_EVENT: + /* The event system doesn't send any data in buffer */ + schedule_work(&client_data->work_ec_evt); + + break; + + default: + dev_err(dev, "Invalid channel=%02d\n", in_msg->hdr.channel); + } + +end_error: + /* Free the buffer */ + ishtp_cl_io_rb_recycle(rb_in_proc); + + up_read(&init_lock); +} + +/** + * ish_event_cb() - bus driver callback for incoming message + * @cl_device: ISHTP client device for which this message is targeted. + * + * Remove the packet from the list and process the message by calling + * process_recv. + */ +static void ish_event_cb(struct ishtp_cl_device *cl_device) +{ + struct ishtp_cl_rb *rb_in_proc; + struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); + + while ((rb_in_proc = ishtp_cl_rx_get_rb(cros_ish_cl)) != NULL) { + /* Decide what to do with received data */ + process_recv(cros_ish_cl, rb_in_proc); + } +} + +/** + * cros_ish_init() - Init function for ISHTP client + * @cros_ish_cl: ISHTP client instance + * + * This function complete the initializtion of the client. + * + * Return: 0 for success, negative error code for failure. + */ +static int cros_ish_init(struct ishtp_cl *cros_ish_cl) +{ + int rv; + struct ishtp_device *dev; + struct ishtp_fw_client *fw_client; + struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); + + rv = ishtp_cl_link(cros_ish_cl); + if (rv) { + dev_err(cl_data_to_dev(client_data), + "ishtp_cl_link failed\n"); + return rv; + } + + dev = ishtp_get_ishtp_device(cros_ish_cl); + + /* Connect to firmware client */ + ishtp_set_tx_ring_size(cros_ish_cl, CROS_ISH_CL_TX_RING_SIZE); + ishtp_set_rx_ring_size(cros_ish_cl, CROS_ISH_CL_RX_RING_SIZE); + + fw_client = ishtp_fw_cl_get_client(dev, &cros_ish_guid); + if (!fw_client) { + dev_err(cl_data_to_dev(client_data), + "ish client uuid not found\n"); + rv = -ENOENT; + goto err_cl_unlink; + } + + ishtp_cl_set_fw_client_id(cros_ish_cl, + ishtp_get_fw_client_id(fw_client)); + ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_CONNECTING); + + rv = ishtp_cl_connect(cros_ish_cl); + if (rv) { + dev_err(cl_data_to_dev(client_data), + "client connect fail\n"); + goto err_cl_unlink; + } + + ishtp_register_event_cb(client_data->cl_device, ish_event_cb); + return 0; + +err_cl_unlink: + ishtp_cl_unlink(cros_ish_cl); + return rv; +} + +/** + * cros_ish_deinit() - Deinit function for ISHTP client + * @cros_ish_cl: ISHTP client instance + * + * Unlink and free cros_ec client + */ +static void cros_ish_deinit(struct ishtp_cl *cros_ish_cl) +{ + ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_DISCONNECTING); + ishtp_cl_disconnect(cros_ish_cl); + ishtp_cl_unlink(cros_ish_cl); + ishtp_cl_flush_queues(cros_ish_cl); + + /* Disband and free all Tx and Rx client-level rings */ + ishtp_cl_free(cros_ish_cl); +} + +/** + * prepare_cros_ec_rx() - Check & prepare receive buffer + * @ec_dev: CrOS EC MFD device. + * @in_msg: Incoming message buffer + * @msg: cros_ec command used to send & receive data + * + * Return: 0 for success, negative error code for failure. + * + * Check the received buffer. Convert to cros_ec_command format. + */ +static int prepare_cros_ec_rx(struct cros_ec_device *ec_dev, + const struct cros_ish_in_msg *in_msg, + struct cros_ec_command *msg) +{ + u8 sum = 0; + int i, rv, offset; + + /* Check response error code */ + msg->result = in_msg->ec_response.result; + rv = cros_ec_check_result(ec_dev, msg); + if (rv < 0) + return rv; + + if (in_msg->ec_response.data_len > msg->insize) { + dev_err(ec_dev->dev, "Packet too long (%d bytes, expected %d)", + in_msg->ec_response.data_len, msg->insize); + return -ENOSPC; + } + + /* Copy response packet payload and compute checksum */ + for (i = 0; i < sizeof(struct ec_host_response); i++) + sum += ((u8 *)in_msg)[IN_MSG_EC_RESPONSE_PREAMBLE + i]; + + offset = sizeof(struct cros_ish_in_msg); + for (i = 0; i < in_msg->ec_response.data_len; i++) + sum += msg->data[i] = ((u8 *)in_msg)[offset + i]; + + if (sum) { + dev_dbg(ec_dev->dev, "Bad received packet checksum %d\n", sum); + return -EBADMSG; + } + + return 0; +} + +static int cros_ec_pkt_xfer_ish(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg) +{ + int rv; + struct ishtp_cl *cros_ish_cl = ec_dev->priv; + struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); + struct device *dev = cl_data_to_dev(client_data); + struct cros_ish_in_msg *in_msg = (struct cros_ish_in_msg *)ec_dev->din; + struct cros_ish_out_msg *out_msg = + (struct cros_ish_out_msg *)ec_dev->dout; + size_t in_size = sizeof(struct cros_ish_in_msg) + msg->insize; + size_t out_size = sizeof(struct cros_ish_out_msg) + msg->outsize; + + /* Sanity checks */ + if (in_size > ec_dev->din_size) { + dev_err(dev, + "Incoming payload size %zu is too large for ec_dev->din_size %d\n", + in_size, ec_dev->din_size); + return -EMSGSIZE; + } + + if (out_size > ec_dev->dout_size) { + dev_err(dev, + "Outgoing payload size %zu is too large for ec_dev->dout_size %d\n", + out_size, ec_dev->dout_size); + return -EMSGSIZE; + } + + /* Proceed only if reset-init is not in progress */ + if (!down_read_trylock(&init_lock)) { + dev_warn(dev, + "Host is not ready to send messages to ISH. Try again\n"); + return -EAGAIN; + } + + /* Prepare the package to be sent over ISH TP */ + out_msg->hdr.channel = CROS_EC_COMMAND; + out_msg->hdr.status = 0; + + ec_dev->dout += OUT_MSG_EC_REQUEST_PREAMBLE; + cros_ec_prepare_tx(ec_dev, msg); + ec_dev->dout -= OUT_MSG_EC_REQUEST_PREAMBLE; + + dev_dbg(dev, + "out_msg: struct_ver=0x%x checksum=0x%x command=0x%x command_ver=0x%x data_len=0x%x\n", + out_msg->ec_request.struct_version, + out_msg->ec_request.checksum, + out_msg->ec_request.command, + out_msg->ec_request.command_version, + out_msg->ec_request.data_len); + + /* Send command to ISH EC firmware and read response */ + rv = ish_send(client_data, + (u8 *)out_msg, out_size, + (u8 *)in_msg, in_size); + if (rv < 0) + goto end_error; + + rv = prepare_cros_ec_rx(ec_dev, in_msg, msg); + if (rv) + goto end_error; + + rv = in_msg->ec_response.data_len; + + dev_dbg(dev, + "in_msg: struct_ver=0x%x checksum=0x%x result=0x%x data_len=0x%x\n", + in_msg->ec_response.struct_version, + in_msg->ec_response.checksum, + in_msg->ec_response.result, + in_msg->ec_response.data_len); + +end_error: + if (msg->command == EC_CMD_REBOOT_EC) + msleep(EC_REBOOT_DELAY_MS); + + up_read(&init_lock); + + return rv; +} + +static int cros_ec_dev_init(struct ishtp_cl_data *client_data) +{ + struct cros_ec_device *ec_dev; + struct device *dev = cl_data_to_dev(client_data); + + ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL); + if (!ec_dev) + return -ENOMEM; + + client_data->ec_dev = ec_dev; + dev->driver_data = ec_dev; + + ec_dev->dev = dev; + ec_dev->priv = client_data->cros_ish_cl; + ec_dev->cmd_xfer = NULL; + ec_dev->pkt_xfer = cros_ec_pkt_xfer_ish; + ec_dev->phys_name = dev_name(dev); + ec_dev->din_size = sizeof(struct cros_ish_in_msg) + + sizeof(struct ec_response_get_protocol_info); + ec_dev->dout_size = sizeof(struct cros_ish_out_msg); + + return cros_ec_register(ec_dev); +} + +static void reset_handler(struct work_struct *work) +{ + int rv; + struct device *dev; + struct ishtp_cl *cros_ish_cl; + struct ishtp_cl_device *cl_device; + struct ishtp_cl_data *client_data = + container_of(work, struct ishtp_cl_data, work_ishtp_reset); + + /* Lock for reset to complete */ + down_write(&init_lock); + + cros_ish_cl = client_data->cros_ish_cl; + cl_device = client_data->cl_device; + + /* Unlink, flush queues & start again */ + ishtp_cl_unlink(cros_ish_cl); + ishtp_cl_flush_queues(cros_ish_cl); + ishtp_cl_free(cros_ish_cl); + + cros_ish_cl = ishtp_cl_allocate(cl_device); + if (!cros_ish_cl) { + up_write(&init_lock); + return; + } + + ishtp_set_drvdata(cl_device, cros_ish_cl); + ishtp_set_client_data(cros_ish_cl, client_data); + client_data->cros_ish_cl = cros_ish_cl; + + rv = cros_ish_init(cros_ish_cl); + if (rv) { + ishtp_cl_free(cros_ish_cl); + dev_err(cl_data_to_dev(client_data), "Reset Failed\n"); + up_write(&init_lock); + return; + } + + /* Refresh ec_dev device pointers */ + client_data->ec_dev->priv = client_data->cros_ish_cl; + dev = cl_data_to_dev(client_data); + dev->driver_data = client_data->ec_dev; + + dev_info(cl_data_to_dev(client_data), "Chrome EC ISH reset done\n"); + + up_write(&init_lock); +} + +/** + * cros_ec_ishtp_probe() - ISHTP client driver probe callback + * @cl_device: ISHTP client device instance + * + * Return: 0 for success, negative error code for failure. + */ +static int cros_ec_ishtp_probe(struct ishtp_cl_device *cl_device) +{ + int rv; + struct ishtp_cl *cros_ish_cl; + struct ishtp_cl_data *client_data = + devm_kzalloc(ishtp_device(cl_device), + sizeof(*client_data), GFP_KERNEL); + if (!client_data) + return -ENOMEM; + + /* Lock for initialization to complete */ + down_write(&init_lock); + + cros_ish_cl = ishtp_cl_allocate(cl_device); + if (!cros_ish_cl) { + rv = -ENOMEM; + goto end_ishtp_cl_alloc_error; + } + + ishtp_set_drvdata(cl_device, cros_ish_cl); + ishtp_set_client_data(cros_ish_cl, client_data); + client_data->cros_ish_cl = cros_ish_cl; + client_data->cl_device = cl_device; + + init_waitqueue_head(&client_data->response.wait_queue); + + INIT_WORK(&client_data->work_ishtp_reset, + reset_handler); + INIT_WORK(&client_data->work_ec_evt, + ish_evt_handler); + + rv = cros_ish_init(cros_ish_cl); + if (rv) + goto end_ishtp_cl_init_error; + + ishtp_get_device(cl_device); + + up_write(&init_lock); + + /* Register croc_ec_dev mfd */ + rv = cros_ec_dev_init(client_data); + if (rv) + goto end_cros_ec_dev_init_error; + + return 0; + +end_cros_ec_dev_init_error: + ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_DISCONNECTING); + ishtp_cl_disconnect(cros_ish_cl); + ishtp_cl_unlink(cros_ish_cl); + ishtp_cl_flush_queues(cros_ish_cl); + ishtp_put_device(cl_device); +end_ishtp_cl_init_error: + ishtp_cl_free(cros_ish_cl); +end_ishtp_cl_alloc_error: + up_write(&init_lock); + return rv; +} + +/** + * cros_ec_ishtp_remove() - ISHTP client driver remove callback + * @cl_device: ISHTP client device instance + * + * Return: 0 + */ +static int cros_ec_ishtp_remove(struct ishtp_cl_device *cl_device) +{ + struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); + struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); + + cancel_work_sync(&client_data->work_ishtp_reset); + cancel_work_sync(&client_data->work_ec_evt); + cros_ish_deinit(cros_ish_cl); + ishtp_put_device(cl_device); + + return 0; +} + +/** + * cros_ec_ishtp_reset() - ISHTP client driver reset callback + * @cl_device: ISHTP client device instance + * + * Return: 0 + */ +static int cros_ec_ishtp_reset(struct ishtp_cl_device *cl_device) +{ + struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); + struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); + + schedule_work(&client_data->work_ishtp_reset); + + return 0; +} + +/** + * cros_ec_ishtp_suspend() - ISHTP client driver suspend callback + * @device: device instance + * + * Return: 0 for success, negative error code for failure. + */ +static int __maybe_unused cros_ec_ishtp_suspend(struct device *device) +{ + struct ishtp_cl_device *cl_device = dev_get_drvdata(device); + struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); + struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); + + return cros_ec_suspend(client_data->ec_dev); +} + +/** + * cros_ec_ishtp_resume() - ISHTP client driver resume callback + * @device: device instance + * + * Return: 0 for success, negative error code for failure. + */ +static int __maybe_unused cros_ec_ishtp_resume(struct device *device) +{ + struct ishtp_cl_device *cl_device = dev_get_drvdata(device); + struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); + struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); + + return cros_ec_resume(client_data->ec_dev); +} + +static SIMPLE_DEV_PM_OPS(cros_ec_ishtp_pm_ops, cros_ec_ishtp_suspend, + cros_ec_ishtp_resume); + +static struct ishtp_cl_driver cros_ec_ishtp_driver = { + .name = "cros_ec_ishtp", + .guid = &cros_ish_guid, + .probe = cros_ec_ishtp_probe, + .remove = cros_ec_ishtp_remove, + .reset = cros_ec_ishtp_reset, + .driver = { + .pm = &cros_ec_ishtp_pm_ops, + }, +}; + +static int __init cros_ec_ishtp_mod_init(void) +{ + return ishtp_cl_driver_register(&cros_ec_ishtp_driver, THIS_MODULE); +} + +static void __exit cros_ec_ishtp_mod_exit(void) +{ + ishtp_cl_driver_unregister(&cros_ec_ishtp_driver); +} + +module_init(cros_ec_ishtp_mod_init); +module_exit(cros_ec_ishtp_mod_exit); + +MODULE_DESCRIPTION("ChromeOS EC ISHTP Client Driver"); +MODULE_AUTHOR("Rushikesh S Kadam <rushikesh.s.kadam@intel.com>"); + +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("ishtp:*"); diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c index d30a6650b0b5..23a82ee4c785 100644 --- a/drivers/platform/chrome/cros_ec_lightbar.c +++ b/drivers/platform/chrome/cros_ec_lightbar.c @@ -547,7 +547,7 @@ static struct attribute *__lb_cmds_attrs[] = { NULL, }; -struct attribute_group cros_ec_lightbar_attr_group = { +static struct attribute_group cros_ec_lightbar_attr_group = { .name = "lightbar", .attrs = __lb_cmds_attrs, }; diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c index c9c240fbe7c6..aaa21803633a 100644 --- a/drivers/platform/chrome/cros_ec_lpc.c +++ b/drivers/platform/chrome/cros_ec_lpc.c @@ -405,7 +405,7 @@ static int cros_ec_lpc_resume(struct device *dev) } #endif -const struct dev_pm_ops cros_ec_lpc_pm_ops = { +static const struct dev_pm_ops cros_ec_lpc_pm_ops = { SET_LATE_SYSTEM_SLEEP_PM_OPS(cros_ec_lpc_suspend, cros_ec_lpc_resume) }; diff --git a/drivers/platform/chrome/cros_ec_spi.c b/drivers/platform/chrome/cros_ec_spi.c index 8e9451720e73..006a8ff64057 100644 --- a/drivers/platform/chrome/cros_ec_spi.c +++ b/drivers/platform/chrome/cros_ec_spi.c @@ -12,7 +12,7 @@ #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/spi/spi.h> - +#include <uapi/linux/sched/types.h> /* The header byte, which follows the preamble */ #define EC_MSG_HEADER 0xec @@ -67,12 +67,14 @@ * is sent when we want to turn on CS at the start of a transaction. * @end_of_msg_delay: used to set the delay_usecs on the spi_transfer that * is sent when we want to turn off CS at the end of a transaction. + * @high_pri_worker: Used to schedule high priority work. */ struct cros_ec_spi { struct spi_device *spi; s64 last_transfer_ns; unsigned int start_of_msg_delay; unsigned int end_of_msg_delay; + struct kthread_worker *high_pri_worker; }; typedef int (*cros_ec_xfer_fn_t) (struct cros_ec_device *ec_dev, @@ -89,7 +91,7 @@ typedef int (*cros_ec_xfer_fn_t) (struct cros_ec_device *ec_dev, */ struct cros_ec_xfer_work_params { - struct work_struct work; + struct kthread_work work; cros_ec_xfer_fn_t fn; struct cros_ec_device *ec_dev; struct cros_ec_command *ec_msg; @@ -632,7 +634,7 @@ exit: return ret; } -static void cros_ec_xfer_high_pri_work(struct work_struct *work) +static void cros_ec_xfer_high_pri_work(struct kthread_work *work) { struct cros_ec_xfer_work_params *params; @@ -644,12 +646,14 @@ static int cros_ec_xfer_high_pri(struct cros_ec_device *ec_dev, struct cros_ec_command *ec_msg, cros_ec_xfer_fn_t fn) { - struct cros_ec_xfer_work_params params; - - INIT_WORK_ONSTACK(¶ms.work, cros_ec_xfer_high_pri_work); - params.ec_dev = ec_dev; - params.ec_msg = ec_msg; - params.fn = fn; + struct cros_ec_spi *ec_spi = ec_dev->priv; + struct cros_ec_xfer_work_params params = { + .work = KTHREAD_WORK_INIT(params.work, + cros_ec_xfer_high_pri_work), + .ec_dev = ec_dev, + .ec_msg = ec_msg, + .fn = fn, + }; /* * This looks a bit ridiculous. Why do the work on a @@ -660,9 +664,8 @@ static int cros_ec_xfer_high_pri(struct cros_ec_device *ec_dev, * context switched out for too long and the EC giving up on * the transfer. */ - queue_work(system_highpri_wq, ¶ms.work); - flush_work(¶ms.work); - destroy_work_on_stack(¶ms.work); + kthread_queue_work(ec_spi->high_pri_worker, ¶ms.work); + kthread_flush_work(¶ms.work); return params.ret; } @@ -694,6 +697,40 @@ static void cros_ec_spi_dt_probe(struct cros_ec_spi *ec_spi, struct device *dev) ec_spi->end_of_msg_delay = val; } +static void cros_ec_spi_high_pri_release(void *worker) +{ + kthread_destroy_worker(worker); +} + +static int cros_ec_spi_devm_high_pri_alloc(struct device *dev, + struct cros_ec_spi *ec_spi) +{ + struct sched_param sched_priority = { + .sched_priority = MAX_RT_PRIO - 1, + }; + int err; + + ec_spi->high_pri_worker = + kthread_create_worker(0, "cros_ec_spi_high_pri"); + + if (IS_ERR(ec_spi->high_pri_worker)) { + err = PTR_ERR(ec_spi->high_pri_worker); + dev_err(dev, "Can't create cros_ec high pri worker: %d\n", err); + return err; + } + + err = devm_add_action_or_reset(dev, cros_ec_spi_high_pri_release, + ec_spi->high_pri_worker); + if (err) + return err; + + err = sched_setscheduler_nocheck(ec_spi->high_pri_worker->task, + SCHED_FIFO, &sched_priority); + if (err) + dev_err(dev, "Can't set cros_ec high pri priority: %d\n", err); + return err; +} + static int cros_ec_spi_probe(struct spi_device *spi) { struct device *dev = &spi->dev; @@ -703,6 +740,7 @@ static int cros_ec_spi_probe(struct spi_device *spi) spi->bits_per_word = 8; spi->mode = SPI_MODE_0; + spi->rt = true; err = spi_setup(spi); if (err < 0) return err; @@ -732,6 +770,10 @@ static int cros_ec_spi_probe(struct spi_device *spi) ec_spi->last_transfer_ns = ktime_get_ns(); + err = cros_ec_spi_devm_high_pri_alloc(dev, ec_spi); + if (err) + return err; + err = cros_ec_register(ec_dev); if (err) { dev_err(dev, "cannot register EC\n"); @@ -777,7 +819,7 @@ MODULE_DEVICE_TABLE(spi, cros_ec_spi_id); static struct spi_driver cros_ec_driver_spi = { .driver = { .name = "cros-ec-spi", - .of_match_table = of_match_ptr(cros_ec_spi_of_match), + .of_match_table = cros_ec_spi_of_match, .pm = &cros_ec_spi_pm_ops, }, .probe = cros_ec_spi_probe, diff --git a/drivers/platform/chrome/cros_ec_sysfs.c b/drivers/platform/chrome/cros_ec_sysfs.c index fe0b7614ae1b..3edb237bf8ed 100644 --- a/drivers/platform/chrome/cros_ec_sysfs.c +++ b/drivers/platform/chrome/cros_ec_sysfs.c @@ -335,7 +335,7 @@ static umode_t cros_ec_ctrl_visible(struct kobject *kobj, return a->mode; } -struct attribute_group cros_ec_attr_group = { +static struct attribute_group cros_ec_attr_group = { .attrs = __ec_attrs, .is_visible = cros_ec_ctrl_visible, }; diff --git a/drivers/platform/chrome/cros_ec_vbc.c b/drivers/platform/chrome/cros_ec_vbc.c index 8392a1ec33a7..2aaefed87eb4 100644 --- a/drivers/platform/chrome/cros_ec_vbc.c +++ b/drivers/platform/chrome/cros_ec_vbc.c @@ -101,7 +101,7 @@ static struct bin_attribute *cros_ec_vbc_bin_attrs[] = { NULL }; -struct attribute_group cros_ec_vbc_attr_group = { +static struct attribute_group cros_ec_vbc_attr_group = { .name = "vbc", .bin_attrs = cros_ec_vbc_bin_attrs, }; diff --git a/drivers/platform/chrome/wilco_ec/Kconfig b/drivers/platform/chrome/wilco_ec/Kconfig index e09e4cebe9b4..90336874af59 100644 --- a/drivers/platform/chrome/wilco_ec/Kconfig +++ b/drivers/platform/chrome/wilco_ec/Kconfig @@ -18,3 +18,19 @@ config WILCO_EC_DEBUGFS manipulation and allow for testing arbitrary commands. This interface is intended for debug only and will not be present on production devices. + +config WILCO_EC_EVENTS + tristate "Enable event forwarding from EC to userspace" + depends on WILCO_EC + help + If you say Y here, you get support for the EC to send events + (such as power state changes) to userspace. The EC sends the events + over ACPI, and a driver queues up the events to be read by a + userspace daemon from /dev/wilco_event using read() and poll(). + +config WILCO_EC_TELEMETRY + tristate "Enable querying telemetry data from EC" + depends on WILCO_EC + help + If you say Y here, you get support to query EC telemetry data from + /dev/wilco_telem0 using write() and then read(). diff --git a/drivers/platform/chrome/wilco_ec/Makefile b/drivers/platform/chrome/wilco_ec/Makefile index 063e7fb4ea17..bc817164596e 100644 --- a/drivers/platform/chrome/wilco_ec/Makefile +++ b/drivers/platform/chrome/wilco_ec/Makefile @@ -1,6 +1,10 @@ # SPDX-License-Identifier: GPL-2.0 -wilco_ec-objs := core.o mailbox.o +wilco_ec-objs := core.o mailbox.o properties.o sysfs.o obj-$(CONFIG_WILCO_EC) += wilco_ec.o wilco_ec_debugfs-objs := debugfs.o obj-$(CONFIG_WILCO_EC_DEBUGFS) += wilco_ec_debugfs.o +wilco_ec_events-objs := event.o +obj-$(CONFIG_WILCO_EC_EVENTS) += wilco_ec_events.o +wilco_ec_telem-objs := telemetry.o +obj-$(CONFIG_WILCO_EC_TELEMETRY) += wilco_ec_telem.o diff --git a/drivers/platform/chrome/wilco_ec/core.c b/drivers/platform/chrome/wilco_ec/core.c index 05e1e2be1c91..3724bf4b77c6 100644 --- a/drivers/platform/chrome/wilco_ec/core.c +++ b/drivers/platform/chrome/wilco_ec/core.c @@ -52,9 +52,7 @@ static int wilco_ec_probe(struct platform_device *pdev) ec->dev = dev; mutex_init(&ec->mailbox_lock); - /* Largest data buffer size requirement is extended data response */ - ec->data_size = sizeof(struct wilco_ec_response) + - EC_MAILBOX_DATA_SIZE_EXTENDED; + ec->data_size = sizeof(struct wilco_ec_response) + EC_MAILBOX_DATA_SIZE; ec->data_buffer = devm_kzalloc(dev, ec->data_size, GFP_KERNEL); if (!ec->data_buffer) return -ENOMEM; @@ -89,8 +87,28 @@ static int wilco_ec_probe(struct platform_device *pdev) goto unregister_debugfs; } + ret = wilco_ec_add_sysfs(ec); + if (ret < 0) { + dev_err(dev, "Failed to create sysfs entries: %d", ret); + goto unregister_rtc; + } + + /* Register child device that will be found by the telemetry driver. */ + ec->telem_pdev = platform_device_register_data(dev, "wilco_telem", + PLATFORM_DEVID_AUTO, + ec, sizeof(*ec)); + if (IS_ERR(ec->telem_pdev)) { + dev_err(dev, "Failed to create telemetry platform device\n"); + ret = PTR_ERR(ec->telem_pdev); + goto remove_sysfs; + } + return 0; +remove_sysfs: + wilco_ec_remove_sysfs(ec); +unregister_rtc: + platform_device_unregister(ec->rtc_pdev); unregister_debugfs: if (ec->debugfs_pdev) platform_device_unregister(ec->debugfs_pdev); @@ -102,6 +120,8 @@ static int wilco_ec_remove(struct platform_device *pdev) { struct wilco_ec_device *ec = platform_get_drvdata(pdev); + wilco_ec_remove_sysfs(ec); + platform_device_unregister(ec->telem_pdev); platform_device_unregister(ec->rtc_pdev); if (ec->debugfs_pdev) platform_device_unregister(ec->debugfs_pdev); diff --git a/drivers/platform/chrome/wilco_ec/debugfs.c b/drivers/platform/chrome/wilco_ec/debugfs.c index f163476d080d..8d65a1e2f1a3 100644 --- a/drivers/platform/chrome/wilco_ec/debugfs.c +++ b/drivers/platform/chrome/wilco_ec/debugfs.c @@ -16,14 +16,14 @@ #define DRV_NAME "wilco-ec-debugfs" -/* The 256 raw bytes will take up more space when represented as a hex string */ -#define FORMATTED_BUFFER_SIZE (EC_MAILBOX_DATA_SIZE_EXTENDED * 4) +/* The raw bytes will take up more space when represented as a hex string */ +#define FORMATTED_BUFFER_SIZE (EC_MAILBOX_DATA_SIZE * 4) struct wilco_ec_debugfs { struct wilco_ec_device *ec; struct dentry *dir; size_t response_size; - u8 raw_data[EC_MAILBOX_DATA_SIZE_EXTENDED]; + u8 raw_data[EC_MAILBOX_DATA_SIZE]; u8 formatted_data[FORMATTED_BUFFER_SIZE]; }; static struct wilco_ec_debugfs *debug_info; @@ -124,12 +124,6 @@ static ssize_t raw_write(struct file *file, const char __user *user_buf, msg.response_data = debug_info->raw_data; msg.response_size = EC_MAILBOX_DATA_SIZE; - /* Telemetry commands use extended response data */ - if (msg.type == WILCO_EC_MSG_TELEMETRY_LONG) { - msg.flags |= WILCO_EC_FLAG_EXTENDED_DATA; - msg.response_size = EC_MAILBOX_DATA_SIZE_EXTENDED; - } - ret = wilco_ec_mailbox(debug_info->ec, &msg); if (ret < 0) return ret; diff --git a/drivers/platform/chrome/wilco_ec/event.c b/drivers/platform/chrome/wilco_ec/event.c new file mode 100644 index 000000000000..4d2776f77dbd --- /dev/null +++ b/drivers/platform/chrome/wilco_ec/event.c @@ -0,0 +1,541 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ACPI event handling for Wilco Embedded Controller + * + * Copyright 2019 Google LLC + * + * The Wilco Embedded Controller can create custom events that + * are not handled as standard ACPI objects. These events can + * contain information about changes in EC controlled features, + * such as errors and events in the dock or display. For example, + * an event is triggered if the dock is plugged into a display + * incorrectly. These events are needed for telemetry and + * diagnostics reasons, and for possibly alerting the user. + + * These events are triggered by the EC with an ACPI Notify(0x90), + * and then the BIOS reads the event buffer from EC RAM via an + * ACPI method. When the OS receives these events via ACPI, + * it passes them along to this driver. The events are put into + * a queue which can be read by a userspace daemon via a char device + * that implements read() and poll(). The event queue acts as a + * circular buffer of size 64, so if there are no userspace consumers + * the kernel will not run out of memory. The char device will appear at + * /dev/wilco_event{n}, where n is some small non-negative integer, + * starting from 0. Standard ACPI events such as the battery getting + * plugged/unplugged can also come through this path, but they are + * dealt with via other paths, and are ignored here. + + * To test, you can tail the binary data with + * $ cat /dev/wilco_event0 | hexdump -ve '1/1 "%x\n"' + * and then create an event by plugging/unplugging the battery. + */ + +#include <linux/acpi.h> +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/idr.h> +#include <linux/io.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/poll.h> +#include <linux/uaccess.h> +#include <linux/wait.h> + +/* ACPI Notify event code indicating event data is available. */ +#define EC_ACPI_NOTIFY_EVENT 0x90 +/* ACPI Method to execute to retrieve event data buffer from the EC. */ +#define EC_ACPI_GET_EVENT "QSET" +/* Maximum number of words in event data returned by the EC. */ +#define EC_ACPI_MAX_EVENT_WORDS 6 +#define EC_ACPI_MAX_EVENT_SIZE \ + (sizeof(struct ec_event) + (EC_ACPI_MAX_EVENT_WORDS) * sizeof(u16)) + +/* Node will appear in /dev/EVENT_DEV_NAME */ +#define EVENT_DEV_NAME "wilco_event" +#define EVENT_CLASS_NAME EVENT_DEV_NAME +#define DRV_NAME EVENT_DEV_NAME +#define EVENT_DEV_NAME_FMT (EVENT_DEV_NAME "%d") +static struct class event_class = { + .owner = THIS_MODULE, + .name = EVENT_CLASS_NAME, +}; + +/* Keep track of all the device numbers used. */ +#define EVENT_MAX_DEV 128 +static int event_major; +static DEFINE_IDA(event_ida); + +/* Size of circular queue of events. */ +#define MAX_NUM_EVENTS 64 + +/** + * struct event_device_data - Data for a Wilco EC device that responds to ACPI. + * @events: Circular queue of EC events to be provided to userspace. + * @num_events: Number of events in the queue. + * @lock: Mutex to guard the queue. + * @wq: Wait queue to notify processes when events or available or the + * device has been removed. + * @cdev: Char dev that userspace reads() and polls() from. + * @dev: Device associated with the %cdev. + * @exist: Has the device been not been removed? Once a device has been removed, + * writes, reads, and new opens will fail. + * @available: Guarantee only one client can open() file and read from queue. + * + * There will be one of these structs for each ACPI device registered. This data + * is the queue of events received from ACPI that still need to be read from + * userspace (plus a supporting lock and wait queue), as well as the device and + * char device that userspace is using, plus a flag on whether the ACPI device + * has been removed. + */ +struct event_device_data { + struct list_head events; + size_t num_events; + struct mutex lock; + wait_queue_head_t wq; + struct device dev; + struct cdev cdev; + bool exist; + atomic_t available; +}; + +/** + * struct ec_event - Extended event returned by the EC. + * @size: Number of words in structure after the size word. + * @type: Extended event type from &enum ec_event_type. + * @event: Event data words. Max count is %EC_ACPI_MAX_EVENT_WORDS. + */ +struct ec_event { + u16 size; + u16 type; + u16 event[0]; +} __packed; + +/** + * struct ec_event_entry - Event queue entry. + * @list: List node. + * @size: Number of bytes in event structure. + * @event: Extended event returned by the EC. This should be the last + * element because &struct ec_event includes a zero length array. + */ +struct ec_event_entry { + struct list_head list; + size_t size; + struct ec_event event; +}; + +/** + * enqueue_events() - Place EC events in queue to be read by userspace. + * @adev: Device the events came from. + * @buf: Buffer of event data. + * @length: Length of event data buffer. + * + * %buf contains a number of ec_event's, packed one after the other. + * Each ec_event is of variable length. Start with the first event, copy it + * into a containing ev_event_entry, store that entry in a list, move on + * to the next ec_event in buf, and repeat. + * + * Return: 0 on success or negative error code on failure. + */ +static int enqueue_events(struct acpi_device *adev, const u8 *buf, u32 length) +{ + struct event_device_data *dev_data = adev->driver_data; + struct ec_event *event; + struct ec_event_entry *entry, *oldest_entry; + size_t event_size, num_words, word_size; + u32 offset = 0; + + while (offset < length) { + event = (struct ec_event *)(buf + offset); + if (!event) + return -EINVAL; + + /* Number of 16bit event data words is size - 1 */ + num_words = event->size - 1; + word_size = num_words * sizeof(u16); + event_size = sizeof(*event) + word_size; + if (num_words > EC_ACPI_MAX_EVENT_WORDS) { + dev_err(&adev->dev, "Too many event words: %zu > %d\n", + num_words, EC_ACPI_MAX_EVENT_WORDS); + return -EOVERFLOW; + }; + + /* Ensure event does not overflow the available buffer */ + if ((offset + event_size) > length) { + dev_err(&adev->dev, "Event exceeds buffer: %zu > %d\n", + offset + event_size, length); + return -EOVERFLOW; + } + + /* Point to the next event in the buffer */ + offset += event_size; + + /* Create event entry for the queue */ + entry = kzalloc(sizeof(struct ec_event_entry) + word_size, + GFP_KERNEL); + if (!entry) + return -ENOMEM; + entry->size = event_size; + memcpy(&entry->event, event, entry->size); + + mutex_lock(&dev_data->lock); + + /* If the queue is full, delete the oldest event */ + if (dev_data->num_events >= MAX_NUM_EVENTS) { + oldest_entry = list_first_entry(&dev_data->events, + struct ec_event_entry, + list); + list_del(&oldest_entry->list); + kfree(oldest_entry); + dev_data->num_events--; + } + + /* Add this event to the queue */ + list_add_tail(&entry->list, &dev_data->events); + dev_data->num_events++; + + mutex_unlock(&dev_data->lock); + } + + return 0; +} + +/** + * event_device_notify() - Callback when EC generates an event over ACPI. + * @adev: The device that the event is coming from. + * @value: Value passed to Notify() in ACPI. + * + * This function will read the events from the device and enqueue them. + */ +static void event_device_notify(struct acpi_device *adev, u32 value) +{ + struct acpi_buffer event_buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + struct event_device_data *dev_data = adev->driver_data; + union acpi_object *obj; + acpi_status status; + + if (value != EC_ACPI_NOTIFY_EVENT) { + dev_err(&adev->dev, "Invalid event: 0x%08x\n", value); + return; + } + + /* Execute ACPI method to get event data buffer. */ + status = acpi_evaluate_object(adev->handle, EC_ACPI_GET_EVENT, + NULL, &event_buffer); + if (ACPI_FAILURE(status)) { + dev_err(&adev->dev, "Error executing ACPI method %s()\n", + EC_ACPI_GET_EVENT); + return; + } + + obj = (union acpi_object *)event_buffer.pointer; + if (!obj) { + dev_err(&adev->dev, "Nothing returned from %s()\n", + EC_ACPI_GET_EVENT); + return; + } + if (obj->type != ACPI_TYPE_BUFFER) { + dev_err(&adev->dev, "Invalid object returned from %s()\n", + EC_ACPI_GET_EVENT); + kfree(obj); + return; + } + if (obj->buffer.length < sizeof(struct ec_event)) { + dev_err(&adev->dev, "Invalid buffer length %d from %s()\n", + obj->buffer.length, EC_ACPI_GET_EVENT); + kfree(obj); + return; + } + + enqueue_events(adev, obj->buffer.pointer, obj->buffer.length); + kfree(obj); + + if (dev_data->num_events) + wake_up_interruptible(&dev_data->wq); +} + +static int event_open(struct inode *inode, struct file *filp) +{ + struct event_device_data *dev_data; + + dev_data = container_of(inode->i_cdev, struct event_device_data, cdev); + if (!dev_data->exist) + return -ENODEV; + + if (atomic_cmpxchg(&dev_data->available, 1, 0) == 0) + return -EBUSY; + + /* Increase refcount on device so dev_data is not freed */ + get_device(&dev_data->dev); + nonseekable_open(inode, filp); + filp->private_data = dev_data; + + return 0; +} + +static __poll_t event_poll(struct file *filp, poll_table *wait) +{ + struct event_device_data *dev_data = filp->private_data; + __poll_t mask = 0; + + poll_wait(filp, &dev_data->wq, wait); + if (!dev_data->exist) + return EPOLLHUP; + if (dev_data->num_events) + mask |= EPOLLIN | EPOLLRDNORM | EPOLLPRI; + return mask; +} + +/** + * event_read() - Callback for passing event data to userspace via read(). + * @filp: The file we are reading from. + * @buf: Pointer to userspace buffer to fill with one event. + * @count: Number of bytes requested. Must be at least EC_ACPI_MAX_EVENT_SIZE. + * @pos: File position pointer, irrelevant since we don't support seeking. + * + * Fills the passed buffer with the data from the first event in the queue, + * removes that event from the queue. On error, the event remains in the queue. + * + * If there are no events in the the queue, then one of two things happens, + * depending on if the file was opened in nonblocking mode: If in nonblocking + * mode, then return -EAGAIN to say there's no data. If in blocking mode, then + * block until an event is available. + * + * Return: Number of bytes placed in buffer, negative error code on failure. + */ +static ssize_t event_read(struct file *filp, char __user *buf, size_t count, + loff_t *pos) +{ + struct event_device_data *dev_data = filp->private_data; + struct ec_event_entry *entry; + ssize_t n_bytes_written = 0; + int err; + + /* We only will give them the entire event at once */ + if (count != 0 && count < EC_ACPI_MAX_EVENT_SIZE) + return -EINVAL; + + mutex_lock(&dev_data->lock); + + while (dev_data->num_events == 0) { + if (filp->f_flags & O_NONBLOCK) { + mutex_unlock(&dev_data->lock); + return -EAGAIN; + } + /* Need to unlock so that data can actually get added to the + * queue, and since we recheck before use and it's just + * comparing pointers, this is safe unlocked. + */ + mutex_unlock(&dev_data->lock); + err = wait_event_interruptible(dev_data->wq, + dev_data->num_events); + if (err) + return err; + + /* Device was removed as we waited? */ + if (!dev_data->exist) + return -ENODEV; + mutex_lock(&dev_data->lock); + } + + entry = list_first_entry(&dev_data->events, + struct ec_event_entry, list); + n_bytes_written = entry->size; + if (copy_to_user(buf, &entry->event, n_bytes_written)) + return -EFAULT; + list_del(&entry->list); + kfree(entry); + dev_data->num_events--; + + mutex_unlock(&dev_data->lock); + + return n_bytes_written; +} + +static int event_release(struct inode *inode, struct file *filp) +{ + struct event_device_data *dev_data = filp->private_data; + + atomic_set(&dev_data->available, 1); + put_device(&dev_data->dev); + + return 0; +} + +static const struct file_operations event_fops = { + .open = event_open, + .poll = event_poll, + .read = event_read, + .release = event_release, + .llseek = no_llseek, + .owner = THIS_MODULE, +}; + +/** + * free_device_data() - Callback to free the event_device_data structure. + * @d: The device embedded in our device data, which we have been ref counting. + * + * This is called only after event_device_remove() has been called and all + * userspace programs have called event_release() on all the open file + * descriptors. + */ +static void free_device_data(struct device *d) +{ + struct event_device_data *dev_data; + + dev_data = container_of(d, struct event_device_data, dev); + kfree(dev_data); +} + +static void hangup_device(struct event_device_data *dev_data) +{ + mutex_lock(&dev_data->lock); + dev_data->exist = false; + mutex_unlock(&dev_data->lock); + + /* Wake up the waiting processes so they can close. */ + wake_up_interruptible(&dev_data->wq); + put_device(&dev_data->dev); +} + +/** + * event_device_add() - Callback when creating a new device. + * @adev: ACPI device that we will be receiving events from. + * + * This finds a free minor number for the device, allocates and initializes + * some device data, and creates a new device and char dev node. + * + * The device data is freed in free_device_data(), which is called when + * %dev_data->dev is release()ed. This happens after all references to + * %dev_data->dev are dropped, which happens once both event_device_remove() + * has been called and every open()ed file descriptor has been release()ed. + * + * Return: 0 on success, negative error code on failure. + */ +static int event_device_add(struct acpi_device *adev) +{ + struct event_device_data *dev_data; + int error, minor; + + minor = ida_alloc_max(&event_ida, EVENT_MAX_DEV-1, GFP_KERNEL); + if (minor < 0) { + error = minor; + dev_err(&adev->dev, "Failed to find minor number: %d", error); + return error; + } + + dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL); + if (!dev_data) { + error = -ENOMEM; + goto free_minor; + } + + /* Initialize the device data. */ + adev->driver_data = dev_data; + INIT_LIST_HEAD(&dev_data->events); + mutex_init(&dev_data->lock); + init_waitqueue_head(&dev_data->wq); + dev_data->exist = true; + atomic_set(&dev_data->available, 1); + + /* Initialize the device. */ + dev_data->dev.devt = MKDEV(event_major, minor); + dev_data->dev.class = &event_class; + dev_data->dev.release = free_device_data; + dev_set_name(&dev_data->dev, EVENT_DEV_NAME_FMT, minor); + device_initialize(&dev_data->dev); + + /* Initialize the character device, and add it to userspace. */ + cdev_init(&dev_data->cdev, &event_fops); + error = cdev_device_add(&dev_data->cdev, &dev_data->dev); + if (error) + goto free_dev_data; + + return 0; + +free_dev_data: + hangup_device(dev_data); +free_minor: + ida_simple_remove(&event_ida, minor); + return error; +} + +static int event_device_remove(struct acpi_device *adev) +{ + struct event_device_data *dev_data = adev->driver_data; + + cdev_device_del(&dev_data->cdev, &dev_data->dev); + ida_simple_remove(&event_ida, MINOR(dev_data->dev.devt)); + hangup_device(dev_data); + + return 0; +} + +static const struct acpi_device_id event_acpi_ids[] = { + { "GOOG000D", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, event_acpi_ids); + +static struct acpi_driver event_driver = { + .name = DRV_NAME, + .class = DRV_NAME, + .ids = event_acpi_ids, + .ops = { + .add = event_device_add, + .notify = event_device_notify, + .remove = event_device_remove, + }, + .owner = THIS_MODULE, +}; + +static int __init event_module_init(void) +{ + dev_t dev_num = 0; + int ret; + + ret = class_register(&event_class); + if (ret) { + pr_err(DRV_NAME ": Failed registering class: %d", ret); + return ret; + } + + /* Request device numbers, starting with minor=0. Save the major num. */ + ret = alloc_chrdev_region(&dev_num, 0, EVENT_MAX_DEV, EVENT_DEV_NAME); + if (ret) { + pr_err(DRV_NAME ": Failed allocating dev numbers: %d", ret); + goto destroy_class; + } + event_major = MAJOR(dev_num); + + ret = acpi_bus_register_driver(&event_driver); + if (ret < 0) { + pr_err(DRV_NAME ": Failed registering driver: %d\n", ret); + goto unregister_region; + } + + return 0; + +unregister_region: + unregister_chrdev_region(MKDEV(event_major, 0), EVENT_MAX_DEV); +destroy_class: + class_unregister(&event_class); + ida_destroy(&event_ida); + return ret; +} + +static void __exit event_module_exit(void) +{ + acpi_bus_unregister_driver(&event_driver); + unregister_chrdev_region(MKDEV(event_major, 0), EVENT_MAX_DEV); + class_unregister(&event_class); + ida_destroy(&event_ida); +} + +module_init(event_module_init); +module_exit(event_module_exit); + +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_DESCRIPTION("Wilco EC ACPI event driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/platform/chrome/wilco_ec/mailbox.c b/drivers/platform/chrome/wilco_ec/mailbox.c index 7fb58b487963..ced1f9f3dcee 100644 --- a/drivers/platform/chrome/wilco_ec/mailbox.c +++ b/drivers/platform/chrome/wilco_ec/mailbox.c @@ -119,7 +119,6 @@ static int wilco_ec_transfer(struct wilco_ec_device *ec, struct wilco_ec_response *rs; u8 checksum; u8 flag; - size_t size; /* Write request header, then data */ cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, 0, sizeof(*rq), (u8 *)rq); @@ -148,21 +147,11 @@ static int wilco_ec_transfer(struct wilco_ec_device *ec, return -EIO; } - /* - * The EC always returns either EC_MAILBOX_DATA_SIZE or - * EC_MAILBOX_DATA_SIZE_EXTENDED bytes of data, so we need to - * calculate the checksum on **all** of this data, even if we - * won't use all of it. - */ - if (msg->flags & WILCO_EC_FLAG_EXTENDED_DATA) - size = EC_MAILBOX_DATA_SIZE_EXTENDED; - else - size = EC_MAILBOX_DATA_SIZE; - /* Read back response */ rs = ec->data_buffer; checksum = cros_ec_lpc_io_bytes_mec(MEC_IO_READ, 0, - sizeof(*rs) + size, (u8 *)rs); + sizeof(*rs) + EC_MAILBOX_DATA_SIZE, + (u8 *)rs); if (checksum) { dev_dbg(ec->dev, "bad packet checksum 0x%02x\n", rs->checksum); return -EBADMSG; @@ -173,9 +162,9 @@ static int wilco_ec_transfer(struct wilco_ec_device *ec, return -EBADMSG; } - if (rs->data_size != size) { - dev_dbg(ec->dev, "unexpected packet size (%u != %zu)", - rs->data_size, size); + if (rs->data_size != EC_MAILBOX_DATA_SIZE) { + dev_dbg(ec->dev, "unexpected packet size (%u != %u)", + rs->data_size, EC_MAILBOX_DATA_SIZE); return -EMSGSIZE; } diff --git a/drivers/platform/chrome/wilco_ec/properties.c b/drivers/platform/chrome/wilco_ec/properties.c new file mode 100644 index 000000000000..e69682c95ea2 --- /dev/null +++ b/drivers/platform/chrome/wilco_ec/properties.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Google LLC + */ + +#include <linux/platform_data/wilco-ec.h> +#include <linux/string.h> +#include <linux/unaligned/le_memmove.h> + +/* Operation code; what the EC should do with the property */ +enum ec_property_op { + EC_OP_GET = 0, + EC_OP_SET = 1, +}; + +struct ec_property_request { + u8 op; /* One of enum ec_property_op */ + u8 property_id[4]; /* The 32 bit PID is stored Little Endian */ + u8 length; + u8 data[WILCO_EC_PROPERTY_MAX_SIZE]; +} __packed; + +struct ec_property_response { + u8 reserved[2]; + u8 op; /* One of enum ec_property_op */ + u8 property_id[4]; /* The 32 bit PID is stored Little Endian */ + u8 length; + u8 data[WILCO_EC_PROPERTY_MAX_SIZE]; +} __packed; + +static int send_property_msg(struct wilco_ec_device *ec, + struct ec_property_request *rq, + struct ec_property_response *rs) +{ + struct wilco_ec_message ec_msg; + int ret; + + memset(&ec_msg, 0, sizeof(ec_msg)); + ec_msg.type = WILCO_EC_MSG_PROPERTY; + ec_msg.request_data = rq; + ec_msg.request_size = sizeof(*rq); + ec_msg.response_data = rs; + ec_msg.response_size = sizeof(*rs); + + ret = wilco_ec_mailbox(ec, &ec_msg); + if (ret < 0) + return ret; + if (rs->op != rq->op) + return -EBADMSG; + if (memcmp(rq->property_id, rs->property_id, sizeof(rs->property_id))) + return -EBADMSG; + + return 0; +} + +int wilco_ec_get_property(struct wilco_ec_device *ec, + struct wilco_ec_property_msg *prop_msg) +{ + struct ec_property_request rq; + struct ec_property_response rs; + int ret; + + memset(&rq, 0, sizeof(rq)); + rq.op = EC_OP_GET; + put_unaligned_le32(prop_msg->property_id, rq.property_id); + + ret = send_property_msg(ec, &rq, &rs); + if (ret < 0) + return ret; + + prop_msg->length = rs.length; + memcpy(prop_msg->data, rs.data, rs.length); + + return 0; +} +EXPORT_SYMBOL_GPL(wilco_ec_get_property); + +int wilco_ec_set_property(struct wilco_ec_device *ec, + struct wilco_ec_property_msg *prop_msg) +{ + struct ec_property_request rq; + struct ec_property_response rs; + int ret; + + memset(&rq, 0, sizeof(rq)); + rq.op = EC_OP_SET; + put_unaligned_le32(prop_msg->property_id, rq.property_id); + rq.length = prop_msg->length; + memcpy(rq.data, prop_msg->data, prop_msg->length); + + ret = send_property_msg(ec, &rq, &rs); + if (ret < 0) + return ret; + if (rs.length != prop_msg->length) + return -EBADMSG; + + return 0; +} +EXPORT_SYMBOL_GPL(wilco_ec_set_property); + +int wilco_ec_get_byte_property(struct wilco_ec_device *ec, u32 property_id, + u8 *val) +{ + struct wilco_ec_property_msg msg; + int ret; + + msg.property_id = property_id; + + ret = wilco_ec_get_property(ec, &msg); + if (ret < 0) + return ret; + if (msg.length != 1) + return -EBADMSG; + + *val = msg.data[0]; + + return 0; +} +EXPORT_SYMBOL_GPL(wilco_ec_get_byte_property); + +int wilco_ec_set_byte_property(struct wilco_ec_device *ec, u32 property_id, + u8 val) +{ + struct wilco_ec_property_msg msg; + + msg.property_id = property_id; + msg.data[0] = val; + msg.length = 1; + + return wilco_ec_set_property(ec, &msg); +} +EXPORT_SYMBOL_GPL(wilco_ec_set_byte_property); diff --git a/drivers/platform/chrome/wilco_ec/sysfs.c b/drivers/platform/chrome/wilco_ec/sysfs.c new file mode 100644 index 000000000000..3b86a21005d3 --- /dev/null +++ b/drivers/platform/chrome/wilco_ec/sysfs.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Google LLC + * + * Sysfs properties to view and modify EC-controlled features on Wilco devices. + * The entries will appear under /sys/bus/platform/devices/GOOG000C:00/ + * + * See Documentation/ABI/testing/sysfs-platform-wilco-ec for more information. + */ + +#include <linux/platform_data/wilco-ec.h> +#include <linux/sysfs.h> + +#define CMD_KB_CMOS 0x7C +#define SUB_CMD_KB_CMOS_AUTO_ON 0x03 + +struct boot_on_ac_request { + u8 cmd; /* Always CMD_KB_CMOS */ + u8 reserved1; + u8 sub_cmd; /* Always SUB_CMD_KB_CMOS_AUTO_ON */ + u8 reserved3to5[3]; + u8 val; /* Either 0 or 1 */ + u8 reserved7; +} __packed; + +#define CMD_EC_INFO 0x38 +enum get_ec_info_op { + CMD_GET_EC_LABEL = 0, + CMD_GET_EC_REV = 1, + CMD_GET_EC_MODEL = 2, + CMD_GET_EC_BUILD_DATE = 3, +}; + +struct get_ec_info_req { + u8 cmd; /* Always CMD_EC_INFO */ + u8 reserved; + u8 op; /* One of enum get_ec_info_op */ +} __packed; + +struct get_ec_info_resp { + u8 reserved[2]; + char value[9]; /* __nonstring: might not be null terminated */ +} __packed; + +static ssize_t boot_on_ac_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct wilco_ec_device *ec = dev_get_drvdata(dev); + struct boot_on_ac_request rq; + struct wilco_ec_message msg; + int ret; + u8 val; + + ret = kstrtou8(buf, 10, &val); + if (ret < 0) + return ret; + if (val > 1) + return -EINVAL; + + memset(&rq, 0, sizeof(rq)); + rq.cmd = CMD_KB_CMOS; + rq.sub_cmd = SUB_CMD_KB_CMOS_AUTO_ON; + rq.val = val; + + memset(&msg, 0, sizeof(msg)); + msg.type = WILCO_EC_MSG_LEGACY; + msg.request_data = &rq; + msg.request_size = sizeof(rq); + ret = wilco_ec_mailbox(ec, &msg); + if (ret < 0) + return ret; + + return count; +} + +static DEVICE_ATTR_WO(boot_on_ac); + +static ssize_t get_info(struct device *dev, char *buf, enum get_ec_info_op op) +{ + struct wilco_ec_device *ec = dev_get_drvdata(dev); + struct get_ec_info_req req = { .cmd = CMD_EC_INFO, .op = op }; + struct get_ec_info_resp resp; + int ret; + + struct wilco_ec_message msg = { + .type = WILCO_EC_MSG_LEGACY, + .request_data = &req, + .request_size = sizeof(req), + .response_data = &resp, + .response_size = sizeof(resp), + }; + + ret = wilco_ec_mailbox(ec, &msg); + if (ret < 0) + return ret; + + return scnprintf(buf, PAGE_SIZE, "%.*s\n", (int)sizeof(resp.value), + (char *)&resp.value); +} + +static ssize_t version_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return get_info(dev, buf, CMD_GET_EC_LABEL); +} + +static DEVICE_ATTR_RO(version); + +static ssize_t build_revision_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return get_info(dev, buf, CMD_GET_EC_REV); +} + +static DEVICE_ATTR_RO(build_revision); + +static ssize_t build_date_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return get_info(dev, buf, CMD_GET_EC_BUILD_DATE); +} + +static DEVICE_ATTR_RO(build_date); + +static ssize_t model_number_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return get_info(dev, buf, CMD_GET_EC_MODEL); +} + +static DEVICE_ATTR_RO(model_number); + + +static struct attribute *wilco_dev_attrs[] = { + &dev_attr_boot_on_ac.attr, + &dev_attr_build_date.attr, + &dev_attr_build_revision.attr, + &dev_attr_model_number.attr, + &dev_attr_version.attr, + NULL, +}; + +static struct attribute_group wilco_dev_attr_group = { + .attrs = wilco_dev_attrs, +}; + +int wilco_ec_add_sysfs(struct wilco_ec_device *ec) +{ + return sysfs_create_group(&ec->dev->kobj, &wilco_dev_attr_group); +} + +void wilco_ec_remove_sysfs(struct wilco_ec_device *ec) +{ + sysfs_remove_group(&ec->dev->kobj, &wilco_dev_attr_group); +} diff --git a/drivers/platform/chrome/wilco_ec/telemetry.c b/drivers/platform/chrome/wilco_ec/telemetry.c new file mode 100644 index 000000000000..94cdc166c840 --- /dev/null +++ b/drivers/platform/chrome/wilco_ec/telemetry.c @@ -0,0 +1,450 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Telemetry communication for Wilco EC + * + * Copyright 2019 Google LLC + * + * The Wilco Embedded Controller is able to send telemetry data + * which is useful for enterprise applications. A daemon running on + * the OS sends a command to the EC via a write() to a char device, + * and can read the response with a read(). The write() request is + * verified by the driver to ensure that it is performing only one + * of the whitelisted commands, and that no extraneous data is + * being transmitted to the EC. The response is passed directly + * back to the reader with no modification. + * + * The character device will appear as /dev/wilco_telemN, where N + * is some small non-negative integer, starting with 0. Only one + * process may have the file descriptor open at a time. The calling + * userspace program needs to keep the device file descriptor open + * between the calls to write() and read() in order to preserve the + * response. Up to 32 bytes will be available for reading. + * + * For testing purposes, try requesting the EC's firmware build + * date, by sending the WILCO_EC_TELEM_GET_VERSION command with + * argument index=3. i.e. write [0x38, 0x00, 0x03] + * to the device node. An ASCII string of the build date is + * returned. + */ + +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/uaccess.h> + +#define TELEM_DEV_NAME "wilco_telem" +#define TELEM_CLASS_NAME TELEM_DEV_NAME +#define DRV_NAME TELEM_DEV_NAME +#define TELEM_DEV_NAME_FMT (TELEM_DEV_NAME "%d") +static struct class telem_class = { + .owner = THIS_MODULE, + .name = TELEM_CLASS_NAME, +}; + +/* Keep track of all the device numbers used. */ +#define TELEM_MAX_DEV 128 +static int telem_major; +static DEFINE_IDA(telem_ida); + +/* EC telemetry command codes */ +#define WILCO_EC_TELEM_GET_LOG 0x99 +#define WILCO_EC_TELEM_GET_VERSION 0x38 +#define WILCO_EC_TELEM_GET_FAN_INFO 0x2E +#define WILCO_EC_TELEM_GET_DIAG_INFO 0xFA +#define WILCO_EC_TELEM_GET_TEMP_INFO 0x95 +#define WILCO_EC_TELEM_GET_TEMP_READ 0x2C +#define WILCO_EC_TELEM_GET_BATT_EXT_INFO 0x07 + +#define TELEM_ARGS_SIZE_MAX 30 + +/** + * struct wilco_ec_telem_request - Telemetry command and arguments sent to EC. + * @command: One of WILCO_EC_TELEM_GET_* command codes. + * @reserved: Must be 0. + * @args: The first N bytes are one of telem_args_get_* structs, the rest is 0. + */ +struct wilco_ec_telem_request { + u8 command; + u8 reserved; + u8 args[TELEM_ARGS_SIZE_MAX]; +} __packed; + +/* + * The following telem_args_get_* structs are embedded within the |args| field + * of wilco_ec_telem_request. + */ + +struct telem_args_get_log { + u8 log_type; + u8 log_index; +} __packed; + +/* + * Get a piece of info about the EC firmware version: + * 0 = label + * 1 = svn_rev + * 2 = model_no + * 3 = build_date + * 4 = frio_version + */ +struct telem_args_get_version { + u8 index; +} __packed; + +struct telem_args_get_fan_info { + u8 command; + u8 fan_number; + u8 arg; +} __packed; + +struct telem_args_get_diag_info { + u8 type; + u8 sub_type; +} __packed; + +struct telem_args_get_temp_info { + u8 command; + u8 index; + u8 field; + u8 zone; +} __packed; + +struct telem_args_get_temp_read { + u8 sensor_index; +} __packed; + +struct telem_args_get_batt_ext_info { + u8 var_args[5]; +} __packed; + +/** + * check_telem_request() - Ensure that a request from userspace is valid. + * @rq: Request buffer copied from userspace. + * @size: Number of bytes copied from userspace. + * + * Return: 0 if valid, -EINVAL if bad command or reserved byte is non-zero, + * -EMSGSIZE if the request is too long. + * + * We do not want to allow userspace to send arbitrary telemetry commands to + * the EC. Therefore we check to ensure that + * 1. The request follows the format of struct wilco_ec_telem_request. + * 2. The supplied command code is one of the whitelisted commands. + * 3. The request only contains the necessary data for the header and arguments. + */ +static int check_telem_request(struct wilco_ec_telem_request *rq, + size_t size) +{ + size_t max_size = offsetof(struct wilco_ec_telem_request, args); + + if (rq->reserved) + return -EINVAL; + + switch (rq->command) { + case WILCO_EC_TELEM_GET_LOG: + max_size += sizeof(struct telem_args_get_log); + break; + case WILCO_EC_TELEM_GET_VERSION: + max_size += sizeof(struct telem_args_get_version); + break; + case WILCO_EC_TELEM_GET_FAN_INFO: + max_size += sizeof(struct telem_args_get_fan_info); + break; + case WILCO_EC_TELEM_GET_DIAG_INFO: + max_size += sizeof(struct telem_args_get_diag_info); + break; + case WILCO_EC_TELEM_GET_TEMP_INFO: + max_size += sizeof(struct telem_args_get_temp_info); + break; + case WILCO_EC_TELEM_GET_TEMP_READ: + max_size += sizeof(struct telem_args_get_temp_read); + break; + case WILCO_EC_TELEM_GET_BATT_EXT_INFO: + max_size += sizeof(struct telem_args_get_batt_ext_info); + break; + default: + return -EINVAL; + } + + return (size <= max_size) ? 0 : -EMSGSIZE; +} + +/** + * struct telem_device_data - Data for a Wilco EC device that queries telemetry. + * @cdev: Char dev that userspace reads and polls from. + * @dev: Device associated with the %cdev. + * @ec: Wilco EC that we will be communicating with using the mailbox interface. + * @available: Boolean of if the device can be opened. + */ +struct telem_device_data { + struct device dev; + struct cdev cdev; + struct wilco_ec_device *ec; + atomic_t available; +}; + +#define TELEM_RESPONSE_SIZE EC_MAILBOX_DATA_SIZE + +/** + * struct telem_session_data - Data that exists between open() and release(). + * @dev_data: Pointer to get back to the device data and EC. + * @request: Command and arguments sent to EC. + * @response: Response buffer of data from EC. + * @has_msg: Is there data available to read from a previous write? + */ +struct telem_session_data { + struct telem_device_data *dev_data; + struct wilco_ec_telem_request request; + u8 response[TELEM_RESPONSE_SIZE]; + bool has_msg; +}; + +/** + * telem_open() - Callback for when the device node is opened. + * @inode: inode for this char device node. + * @filp: file for this char device node. + * + * We need to ensure that after writing a command to the device, + * the same userspace process reads the corresponding result. + * Therefore, we increment a refcount on opening the device, so that + * only one process can communicate with the EC at a time. + * + * Return: 0 on success, or negative error code on failure. + */ +static int telem_open(struct inode *inode, struct file *filp) +{ + struct telem_device_data *dev_data; + struct telem_session_data *sess_data; + + /* Ensure device isn't already open */ + dev_data = container_of(inode->i_cdev, struct telem_device_data, cdev); + if (atomic_cmpxchg(&dev_data->available, 1, 0) == 0) + return -EBUSY; + + get_device(&dev_data->dev); + + sess_data = kzalloc(sizeof(*sess_data), GFP_KERNEL); + if (!sess_data) { + atomic_set(&dev_data->available, 1); + return -ENOMEM; + } + sess_data->dev_data = dev_data; + sess_data->has_msg = false; + + nonseekable_open(inode, filp); + filp->private_data = sess_data; + + return 0; +} + +static ssize_t telem_write(struct file *filp, const char __user *buf, + size_t count, loff_t *pos) +{ + struct telem_session_data *sess_data = filp->private_data; + struct wilco_ec_message msg = {}; + int ret; + + if (count > sizeof(sess_data->request)) + return -EMSGSIZE; + if (copy_from_user(&sess_data->request, buf, count)) + return -EFAULT; + ret = check_telem_request(&sess_data->request, count); + if (ret < 0) + return ret; + + memset(sess_data->response, 0, sizeof(sess_data->response)); + msg.type = WILCO_EC_MSG_TELEMETRY; + msg.request_data = &sess_data->request; + msg.request_size = sizeof(sess_data->request); + msg.response_data = sess_data->response; + msg.response_size = sizeof(sess_data->response); + + ret = wilco_ec_mailbox(sess_data->dev_data->ec, &msg); + if (ret < 0) + return ret; + if (ret != sizeof(sess_data->response)) + return -EMSGSIZE; + + sess_data->has_msg = true; + + return count; +} + +static ssize_t telem_read(struct file *filp, char __user *buf, size_t count, + loff_t *pos) +{ + struct telem_session_data *sess_data = filp->private_data; + + if (!sess_data->has_msg) + return -ENODATA; + if (count > sizeof(sess_data->response)) + return -EINVAL; + + if (copy_to_user(buf, sess_data->response, count)) + return -EFAULT; + + sess_data->has_msg = false; + + return count; +} + +static int telem_release(struct inode *inode, struct file *filp) +{ + struct telem_session_data *sess_data = filp->private_data; + + atomic_set(&sess_data->dev_data->available, 1); + put_device(&sess_data->dev_data->dev); + kfree(sess_data); + + return 0; +} + +static const struct file_operations telem_fops = { + .open = telem_open, + .write = telem_write, + .read = telem_read, + .release = telem_release, + .llseek = no_llseek, + .owner = THIS_MODULE, +}; + +/** + * telem_device_free() - Callback to free the telem_device_data structure. + * @d: The device embedded in our device data, which we have been ref counting. + * + * Once all open file descriptors are closed and the device has been removed, + * the refcount of the device will fall to 0 and this will be called. + */ +static void telem_device_free(struct device *d) +{ + struct telem_device_data *dev_data; + + dev_data = container_of(d, struct telem_device_data, dev); + kfree(dev_data); +} + +/** + * telem_device_probe() - Callback when creating a new device. + * @pdev: platform device that we will be receiving telems from. + * + * This finds a free minor number for the device, allocates and initializes + * some device data, and creates a new device and char dev node. + * + * Return: 0 on success, negative error code on failure. + */ +static int telem_device_probe(struct platform_device *pdev) +{ + struct telem_device_data *dev_data; + int error, minor; + + /* Get the next available device number */ + minor = ida_alloc_max(&telem_ida, TELEM_MAX_DEV-1, GFP_KERNEL); + if (minor < 0) { + error = minor; + dev_err(&pdev->dev, "Failed to find minor number: %d", error); + return error; + } + + dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL); + if (!dev_data) { + ida_simple_remove(&telem_ida, minor); + return -ENOMEM; + } + + /* Initialize the device data */ + dev_data->ec = dev_get_platdata(&pdev->dev); + atomic_set(&dev_data->available, 1); + platform_set_drvdata(pdev, dev_data); + + /* Initialize the device */ + dev_data->dev.devt = MKDEV(telem_major, minor); + dev_data->dev.class = &telem_class; + dev_data->dev.release = telem_device_free; + dev_set_name(&dev_data->dev, TELEM_DEV_NAME_FMT, minor); + device_initialize(&dev_data->dev); + + /* Initialize the character device and add it to userspace */; + cdev_init(&dev_data->cdev, &telem_fops); + error = cdev_device_add(&dev_data->cdev, &dev_data->dev); + if (error) { + put_device(&dev_data->dev); + ida_simple_remove(&telem_ida, minor); + return error; + } + + return 0; +} + +static int telem_device_remove(struct platform_device *pdev) +{ + struct telem_device_data *dev_data = platform_get_drvdata(pdev); + + cdev_device_del(&dev_data->cdev, &dev_data->dev); + put_device(&dev_data->dev); + ida_simple_remove(&telem_ida, MINOR(dev_data->dev.devt)); + + return 0; +} + +static struct platform_driver telem_driver = { + .probe = telem_device_probe, + .remove = telem_device_remove, + .driver = { + .name = DRV_NAME, + }, +}; + +static int __init telem_module_init(void) +{ + dev_t dev_num = 0; + int ret; + + ret = class_register(&telem_class); + if (ret) { + pr_err(DRV_NAME ": Failed registering class: %d", ret); + return ret; + } + + /* Request the kernel for device numbers, starting with minor=0 */ + ret = alloc_chrdev_region(&dev_num, 0, TELEM_MAX_DEV, TELEM_DEV_NAME); + if (ret) { + pr_err(DRV_NAME ": Failed allocating dev numbers: %d", ret); + goto destroy_class; + } + telem_major = MAJOR(dev_num); + + ret = platform_driver_register(&telem_driver); + if (ret < 0) { + pr_err(DRV_NAME ": Failed registering driver: %d\n", ret); + goto unregister_region; + } + + return 0; + +unregister_region: + unregister_chrdev_region(MKDEV(telem_major, 0), TELEM_MAX_DEV); +destroy_class: + class_unregister(&telem_class); + ida_destroy(&telem_ida); + return ret; +} + +static void __exit telem_module_exit(void) +{ + platform_driver_unregister(&telem_driver); + unregister_chrdev_region(MKDEV(telem_major, 0), TELEM_MAX_DEV); + class_unregister(&telem_class); + ida_destroy(&telem_ida); +} + +module_init(telem_module_init); +module_exit(telem_module_exit); + +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_DESCRIPTION("Wilco EC telemetry driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 5e75944ad5d1..18f70e4bbb31 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1364,10 +1364,32 @@ static void spi_pump_messages(struct kthread_work *work) __spi_pump_messages(ctlr, true); } -static int spi_init_queue(struct spi_controller *ctlr) +/** + * spi_set_thread_rt - set the controller to pump at realtime priority + * @ctlr: controller to boost priority of + * + * This can be called because the controller requested realtime priority + * (by setting the ->rt value before calling spi_register_controller()) or + * because a device on the bus said that its transfers needed realtime + * priority. + * + * NOTE: at the moment if any device on a bus says it needs realtime then + * the thread will be at realtime priority for all transfers on that + * controller. If this eventually becomes a problem we may see if we can + * find a way to boost the priority only temporarily during relevant + * transfers. + */ +static void spi_set_thread_rt(struct spi_controller *ctlr) { struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; + dev_info(&ctlr->dev, + "will run message pump with realtime priority\n"); + sched_setscheduler(ctlr->kworker_task, SCHED_FIFO, ¶m); +} + +static int spi_init_queue(struct spi_controller *ctlr) +{ ctlr->running = false; ctlr->busy = false; @@ -1387,11 +1409,8 @@ static int spi_init_queue(struct spi_controller *ctlr) * request and the scheduling of the message pump thread. Without this * setting the message pump thread will remain at default priority. */ - if (ctlr->rt) { - dev_info(&ctlr->dev, - "will run message pump with realtime priority\n"); - sched_setscheduler(ctlr->kworker_task, SCHED_FIFO, ¶m); - } + if (ctlr->rt) + spi_set_thread_rt(ctlr); return 0; } @@ -2982,6 +3001,11 @@ int spi_setup(struct spi_device *spi) spi_set_cs(spi, false); + if (spi->rt && !spi->controller->rt) { + spi->controller->rt = true; + spi_set_thread_rt(spi->controller); + } + dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", diff --git a/include/linux/platform_data/wilco-ec.h b/include/linux/platform_data/wilco-ec.h index 1ff224793c99..ad03b586a095 100644 --- a/include/linux/platform_data/wilco-ec.h +++ b/include/linux/platform_data/wilco-ec.h @@ -13,12 +13,9 @@ /* Message flags for using the mailbox() interface */ #define WILCO_EC_FLAG_NO_RESPONSE BIT(0) /* EC does not respond */ -#define WILCO_EC_FLAG_EXTENDED_DATA BIT(1) /* EC returns 256 data bytes */ /* Normal commands have a maximum 32 bytes of data */ #define EC_MAILBOX_DATA_SIZE 32 -/* Extended commands have 256 bytes of response data */ -#define EC_MAILBOX_DATA_SIZE_EXTENDED 256 /** * struct wilco_ec_device - Wilco Embedded Controller handle. @@ -32,6 +29,7 @@ * @data_size: Size of the data buffer used for EC communication. * @debugfs_pdev: The child platform_device used by the debugfs sub-driver. * @rtc_pdev: The child platform_device used by the RTC sub-driver. + * @telem_pdev: The child platform_device used by the telemetry sub-driver. */ struct wilco_ec_device { struct device *dev; @@ -43,6 +41,7 @@ struct wilco_ec_device { size_t data_size; struct platform_device *debugfs_pdev; struct platform_device *rtc_pdev; + struct platform_device *telem_pdev; }; /** @@ -85,14 +84,12 @@ struct wilco_ec_response { * enum wilco_ec_msg_type - Message type to select a set of command codes. * @WILCO_EC_MSG_LEGACY: Legacy EC messages for standard EC behavior. * @WILCO_EC_MSG_PROPERTY: Get/Set/Sync EC controlled NVRAM property. - * @WILCO_EC_MSG_TELEMETRY_SHORT: 32 bytes of telemetry data provided by the EC. - * @WILCO_EC_MSG_TELEMETRY_LONG: 256 bytes of telemetry data provided by the EC. + * @WILCO_EC_MSG_TELEMETRY: Request telemetry data from the EC. */ enum wilco_ec_msg_type { WILCO_EC_MSG_LEGACY = 0x00f0, WILCO_EC_MSG_PROPERTY = 0x00f2, - WILCO_EC_MSG_TELEMETRY_SHORT = 0x00f5, - WILCO_EC_MSG_TELEMETRY_LONG = 0x00f6, + WILCO_EC_MSG_TELEMETRY = 0x00f5, }; /** @@ -123,4 +120,87 @@ struct wilco_ec_message { */ int wilco_ec_mailbox(struct wilco_ec_device *ec, struct wilco_ec_message *msg); +/* + * A Property is typically a data item that is stored to NVRAM + * by the EC. Each of these data items has an index associated + * with it, known as the Property ID (PID). Properties may have + * variable lengths, up to a max of WILCO_EC_PROPERTY_MAX_SIZE + * bytes. Properties can be simple integers, or they may be more + * complex binary data. + */ + +#define WILCO_EC_PROPERTY_MAX_SIZE 4 + +/** + * struct ec_property_set_msg - Message to get or set a property. + * @property_id: Which property to get or set. + * @length: Number of bytes of |data| that are used. + * @data: Actual property data. + */ +struct wilco_ec_property_msg { + u32 property_id; + int length; + u8 data[WILCO_EC_PROPERTY_MAX_SIZE]; +}; + +/** + * wilco_ec_get_property() - Retrieve a property from the EC. + * @ec: Embedded Controller device. + * @prop_msg: Message for request and response. + * + * The property_id field of |prop_msg| should be filled before calling this + * function. The result will be stored in the data and length fields. + * + * Return: 0 on success, negative error code on failure. + */ +int wilco_ec_get_property(struct wilco_ec_device *ec, + struct wilco_ec_property_msg *prop_msg); + +/** + * wilco_ec_set_property() - Store a property on the EC. + * @ec: Embedded Controller device. + * @prop_msg: Message for request and response. + * + * The property_id, length, and data fields of |prop_msg| should be + * filled before calling this function. + * + * Return: 0 on success, negative error code on failure. + */ +int wilco_ec_set_property(struct wilco_ec_device *ec, + struct wilco_ec_property_msg *prop_msg); + +/** + * wilco_ec_get_byte_property() - Retrieve a byte-size property from the EC. + * @ec: Embedded Controller device. + * @property_id: Which property to retrieve. + * @val: The result value, will be filled by this function. + * + * Return: 0 on success, negative error code on failure. + */ +int wilco_ec_get_byte_property(struct wilco_ec_device *ec, u32 property_id, + u8 *val); + +/** + * wilco_ec_get_byte_property() - Store a byte-size property on the EC. + * @ec: Embedded Controller device. + * @property_id: Which property to store. + * @val: Value to store. + * + * Return: 0 on success, negative error code on failure. + */ +int wilco_ec_set_byte_property(struct wilco_ec_device *ec, u32 property_id, + u8 val); + +/** + * wilco_ec_add_sysfs() - Create sysfs entries + * @ec: Wilco EC device + * + * wilco_ec_remove_sysfs() needs to be called afterwards + * to perform the necessary cleanup. + * + * Return: 0 on success or negative error code on failure. + */ +int wilco_ec_add_sysfs(struct wilco_ec_device *ec); +void wilco_ec_remove_sysfs(struct wilco_ec_device *ec); + #endif /* WILCO_EC_H */ diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 053abd22ad31..15505c2485d6 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -109,6 +109,7 @@ void spi_statistics_add_transfer_stats(struct spi_statistics *stats, * This may be changed by the device's driver, or left at the * default (0) indicating protocol words are eight bit bytes. * The spi_transfer.bits_per_word can override this for each transfer. + * @rt: Make the pump thread real time priority. * @irq: Negative, or the number passed to request_irq() to receive * interrupts from this device. * @controller_state: Controller's runtime state @@ -143,6 +144,7 @@ struct spi_device { u32 max_speed_hz; u8 chip_select; u8 bits_per_word; + bool rt; u32 mode; #define SPI_CPHA 0x01 /* clock phase */ #define SPI_CPOL 0x02 /* clock polarity */ |