diff options
Diffstat (limited to 'drivers/spmi/spmi.c')
| -rw-r--r-- | drivers/spmi/spmi.c | 574 |
1 files changed, 574 insertions, 0 deletions
diff --git a/drivers/spmi/spmi.c b/drivers/spmi/spmi.c new file mode 100644 index 000000000000..3b5780710d50 --- /dev/null +++ b/drivers/spmi/spmi.c @@ -0,0 +1,574 @@ +/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/idr.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/spmi.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> + +#include <dt-bindings/spmi/spmi.h> + +static DEFINE_IDA(ctrl_ida); + +static void spmi_dev_release(struct device *dev) +{ + struct spmi_device *sdev = to_spmi_device(dev); + kfree(sdev); +} + +static const struct device_type spmi_dev_type = { + .release = spmi_dev_release, +}; + +static void spmi_ctrl_release(struct device *dev) +{ + struct spmi_controller *ctrl = to_spmi_controller(dev); + ida_simple_remove(&ctrl_ida, ctrl->nr); + kfree(ctrl); +} + +static const struct device_type spmi_ctrl_type = { + .release = spmi_ctrl_release, +}; + +static int spmi_device_match(struct device *dev, struct device_driver *drv) +{ + if (of_driver_match_device(dev, drv)) + return 1; + + if (drv->name) + return strncmp(dev_name(dev), drv->name, + SPMI_NAME_SIZE) == 0; + + return 0; +} + +/** + * spmi_device_add() - add a device previously constructed via spmi_device_alloc() + * @sdev: spmi_device to be added + */ +int spmi_device_add(struct spmi_device *sdev) +{ + struct spmi_controller *ctrl = sdev->ctrl; + int err; + + dev_set_name(&sdev->dev, "%d-%02x", ctrl->nr, sdev->usid); + + err = device_add(&sdev->dev); + if (err < 0) { + dev_err(&sdev->dev, "Can't add %s, status %d\n", + dev_name(&sdev->dev), err); + goto err_device_add; + } + + dev_dbg(&sdev->dev, "device %s registered\n", dev_name(&sdev->dev)); + +err_device_add: + return err; +} +EXPORT_SYMBOL_GPL(spmi_device_add); + +/** + * spmi_device_remove(): remove an SPMI device + * @sdev: spmi_device to be removed + */ +void spmi_device_remove(struct spmi_device *sdev) +{ + device_unregister(&sdev->dev); +} +EXPORT_SYMBOL_GPL(spmi_device_remove); + +static inline int +spmi_cmd(struct spmi_controller *ctrl, u8 opcode, u8 sid) +{ + if (!ctrl || !ctrl->cmd || ctrl->dev.type != &spmi_ctrl_type) + return -EINVAL; + + return ctrl->cmd(ctrl, opcode, sid); +} + +static inline int spmi_read_cmd(struct spmi_controller *ctrl, u8 opcode, + u8 sid, u16 addr, u8 *buf, size_t len) +{ + if (!ctrl || !ctrl->read_cmd || ctrl->dev.type != &spmi_ctrl_type) + return -EINVAL; + + return ctrl->read_cmd(ctrl, opcode, sid, addr, buf, len); +} + +static inline int spmi_write_cmd(struct spmi_controller *ctrl, u8 opcode, + u8 sid, u16 addr, const u8 *buf, size_t len) +{ + if (!ctrl || !ctrl->write_cmd || ctrl->dev.type != &spmi_ctrl_type) + return -EINVAL; + + return ctrl->write_cmd(ctrl, opcode, sid, addr, buf, len); +} + +/** + * spmi_register_read() - register read + * @sdev: SPMI device. + * @addr: slave register address (5-bit address). + * @buf: buffer to be populated with data from the Slave. + * + * Reads 1 byte of data from a Slave device register. + */ +int spmi_register_read(struct spmi_device *sdev, u8 addr, u8 *buf) +{ + /* 5-bit register address */ + if (addr > 0x1F) + return -EINVAL; + + return spmi_read_cmd(sdev->ctrl, SPMI_CMD_READ, sdev->usid, addr, + buf, 1); +} +EXPORT_SYMBOL_GPL(spmi_register_read); + +/** + * spmi_ext_register_read() - extended register read + * @sdev: SPMI device. + * @addr: slave register address (8-bit address). + * @buf: buffer to be populated with data from the Slave. + * @len: the request number of bytes to read (up to 16 bytes). + * + * Reads up to 16 bytes of data from the extended register space on a + * Slave device. + */ +int spmi_ext_register_read(struct spmi_device *sdev, u8 addr, u8 *buf, + size_t len) +{ + /* 8-bit register address, up to 16 bytes */ + if (len == 0 || len > 16) + return -EINVAL; + + return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READ, sdev->usid, addr, + buf, len); +} +EXPORT_SYMBOL_GPL(spmi_ext_register_read); + +/** + * spmi_ext_register_readl() - extended register read long + * @sdev: SPMI device. + * @addr: slave register address (16-bit address). + * @buf: buffer to be populated with data from the Slave. + * @len: the request number of bytes to read (up to 8 bytes). + * + * Reads up to 8 bytes of data from the extended register space on a + * Slave device using 16-bit address. + */ +int spmi_ext_register_readl(struct spmi_device *sdev, u16 addr, u8 *buf, + size_t len) +{ + /* 16-bit register address, up to 8 bytes */ + if (len == 0 || len > 8) + return -EINVAL; + + return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READL, sdev->usid, addr, + buf, len); +} +EXPORT_SYMBOL_GPL(spmi_ext_register_readl); + +/** + * spmi_register_write() - register write + * @sdev: SPMI device + * @addr: slave register address (5-bit address). + * @data: buffer containing the data to be transferred to the Slave. + * + * Writes 1 byte of data to a Slave device register. + */ +int spmi_register_write(struct spmi_device *sdev, u8 addr, u8 data) +{ + /* 5-bit register address */ + if (addr > 0x1F) + return -EINVAL; + + return spmi_write_cmd(sdev->ctrl, SPMI_CMD_WRITE, sdev->usid, addr, + &data, 1); +} +EXPORT_SYMBOL_GPL(spmi_register_write); + +/** + * spmi_register_zero_write() - register zero write + * @sdev: SPMI device. + * @data: the data to be written to register 0 (7-bits). + * + * Writes data to register 0 of the Slave device. + */ +int spmi_register_zero_write(struct spmi_device *sdev, u8 data) +{ + return spmi_write_cmd(sdev->ctrl, SPMI_CMD_ZERO_WRITE, sdev->usid, 0, + &data, 1); +} +EXPORT_SYMBOL_GPL(spmi_register_zero_write); + +/** + * spmi_ext_register_write() - extended register write + * @sdev: SPMI device. + * @addr: slave register address (8-bit address). + * @buf: buffer containing the data to be transferred to the Slave. + * @len: the request number of bytes to read (up to 16 bytes). + * + * Writes up to 16 bytes of data to the extended register space of a + * Slave device. + */ +int spmi_ext_register_write(struct spmi_device *sdev, u8 addr, const u8 *buf, + size_t len) +{ + /* 8-bit register address, up to 16 bytes */ + if (len == 0 || len > 16) + return -EINVAL; + + return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITE, sdev->usid, addr, + buf, len); +} +EXPORT_SYMBOL_GPL(spmi_ext_register_write); + +/** + * spmi_ext_register_writel() - extended register write long + * @sdev: SPMI device. + * @addr: slave register address (16-bit address). + * @buf: buffer containing the data to be transferred to the Slave. + * @len: the request number of bytes to read (up to 8 bytes). + * + * Writes up to 8 bytes of data to the extended register space of a + * Slave device using 16-bit address. + */ +int spmi_ext_register_writel(struct spmi_device *sdev, u16 addr, const u8 *buf, + size_t len) +{ + /* 4-bit Slave Identifier, 16-bit register address, up to 8 bytes */ + if (len == 0 || len > 8) + return -EINVAL; + + return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITEL, sdev->usid, + addr, buf, len); +} +EXPORT_SYMBOL_GPL(spmi_ext_register_writel); + +/** + * spmi_command_reset() - sends RESET command to the specified slave + * @sdev: SPMI device. + * + * The Reset command initializes the Slave and forces all registers to + * their reset values. The Slave shall enter the STARTUP state after + * receiving a Reset command. + */ +int spmi_command_reset(struct spmi_device *sdev) +{ + return spmi_cmd(sdev->ctrl, SPMI_CMD_RESET, sdev->usid); +} +EXPORT_SYMBOL_GPL(spmi_command_reset); + +/** + * spmi_command_sleep() - sends SLEEP command to the specified SPMI device + * @sdev: SPMI device. + * + * The Sleep command causes the Slave to enter the user defined SLEEP state. + */ +int spmi_command_sleep(struct spmi_device *sdev) +{ + return spmi_cmd(sdev->ctrl, SPMI_CMD_SLEEP, sdev->usid); +} +EXPORT_SYMBOL_GPL(spmi_command_sleep); + +/** + * spmi_command_wakeup() - sends WAKEUP command to the specified SPMI device + * @sdev: SPMI device. + * + * The Wakeup command causes the Slave to move from the SLEEP state to + * the ACTIVE state. + */ +int spmi_command_wakeup(struct spmi_device *sdev) +{ + return spmi_cmd(sdev->ctrl, SPMI_CMD_WAKEUP, sdev->usid); +} +EXPORT_SYMBOL_GPL(spmi_command_wakeup); + +/** + * spmi_command_shutdown() - sends SHUTDOWN command to the specified SPMI device + * @sdev: SPMI device. + * + * The Shutdown command causes the Slave to enter the SHUTDOWN state. + */ +int spmi_command_shutdown(struct spmi_device *sdev) +{ + return spmi_cmd(sdev->ctrl, SPMI_CMD_SHUTDOWN, sdev->usid); +} +EXPORT_SYMBOL_GPL(spmi_command_shutdown); + +static int spmi_drv_probe(struct device *dev) +{ + const struct spmi_driver *sdrv = to_spmi_driver(dev->driver); + struct spmi_device *sdev = to_spmi_device(dev); + int err; + + /* Ensure the slave is in ACTIVE state */ + err = spmi_command_wakeup(sdev); + if (err) + goto fail_wakeup; + + pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + + err = sdrv->probe(sdev); + if (err) + goto fail_probe; + + return 0; + +fail_probe: + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_put_noidle(dev); +fail_wakeup: + return err; +} + +static int spmi_drv_remove(struct device *dev) +{ + const struct spmi_driver *sdrv = to_spmi_driver(dev->driver); + + pm_runtime_get_sync(dev); + sdrv->remove(to_spmi_device(dev)); + pm_runtime_put_noidle(dev); + + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_put_noidle(dev); + return 0; +} + +static struct bus_type spmi_bus_type = { + .name = "spmi", + .match = spmi_device_match, + .probe = spmi_drv_probe, + .remove = spmi_drv_remove, +}; + +/** + * spmi_controller_alloc() - Allocate a new SPMI device + * @ctrl: associated controller + * + * Caller is responsible for either calling spmi_device_add() to add the + * newly allocated controller, or calling spmi_device_put() to discard it. + */ +struct spmi_device *spmi_device_alloc(struct spmi_controller *ctrl) +{ + struct spmi_device *sdev; + + sdev = kzalloc(sizeof(*sdev), GFP_KERNEL); + if (!sdev) + return NULL; + + sdev->ctrl = ctrl; + device_initialize(&sdev->dev); + sdev->dev.parent = &ctrl->dev; + sdev->dev.bus = &spmi_bus_type; + sdev->dev.type = &spmi_dev_type; + return sdev; +} +EXPORT_SYMBOL_GPL(spmi_device_alloc); + +/** + * spmi_controller_alloc() - Allocate a new SPMI controller + * @parent: parent device + * @size: size of private data + * + * Caller is responsible for either calling spmi_controller_add() to add the + * newly allocated controller, or calling spmi_controller_put() to discard it. + * The allocated private data region may be accessed via + * spmi_controller_get_drvdata() + */ +struct spmi_controller *spmi_controller_alloc(struct device *parent, + size_t size) +{ + struct spmi_controller *ctrl; + int id; + + if (WARN_ON(!parent)) + return NULL; + + ctrl = kzalloc(sizeof(*ctrl) + size, GFP_KERNEL); + if (!ctrl) + return NULL; + + device_initialize(&ctrl->dev); + ctrl->dev.type = &spmi_ctrl_type; + ctrl->dev.bus = &spmi_bus_type; + ctrl->dev.parent = parent; + ctrl->dev.of_node = parent->of_node; + spmi_controller_set_drvdata(ctrl, &ctrl[1]); + + id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL); + if (id < 0) { + dev_err(parent, + "unable to allocate SPMI controller identifier.\n"); + spmi_controller_put(ctrl); + return NULL; + } + + ctrl->nr = id; + dev_set_name(&ctrl->dev, "spmi-%d", id); + + dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id); + return ctrl; +} +EXPORT_SYMBOL_GPL(spmi_controller_alloc); + +static void of_spmi_register_devices(struct spmi_controller *ctrl) +{ + struct device_node *node; + int err; + + if (!ctrl->dev.of_node) + return; + + for_each_available_child_of_node(ctrl->dev.of_node, node) { + struct spmi_device *sdev; + u32 reg[2]; + + dev_dbg(&ctrl->dev, "adding child %s\n", node->full_name); + + err = of_property_read_u32_array(node, "reg", reg, 2); + if (err) { + dev_err(&ctrl->dev, + "node %s err (%d) does not have 'reg' property\n", + node->full_name, err); + continue; + } + + if (reg[1] != SPMI_USID) { + dev_err(&ctrl->dev, + "node %s contains unsupported 'reg' entry\n", + node->full_name); + continue; + } + + if (reg[0] >= SPMI_MAX_SLAVE_ID) { + dev_err(&ctrl->dev, + "invalid usid on node %s\n", + node->full_name); + continue; + } + + dev_dbg(&ctrl->dev, "read usid %02x\n", reg[0]); + + sdev = spmi_device_alloc(ctrl); + if (!sdev) + continue; + + sdev->dev.of_node = node; + sdev->usid = (u8) reg[0]; + + err = spmi_device_add(sdev); + if (err) { + dev_err(&sdev->dev, + "failure adding device. status %d\n", err); + spmi_device_put(sdev); + } + } +} + +/** + * spmi_controller_add() - Add an SPMI controller + * @ctrl: controller to be registered. + * + * Register a controller previously allocated via spmi_controller_alloc() with + * the SPMI core. + */ +int spmi_controller_add(struct spmi_controller *ctrl) +{ + int ret; + + /* Can't register until after driver model init */ + if (WARN_ON(!spmi_bus_type.p)) + return -EAGAIN; + + ret = device_add(&ctrl->dev); + if (ret) + return ret; + + if (IS_ENABLED(CONFIG_OF)) + of_spmi_register_devices(ctrl); + + dev_dbg(&ctrl->dev, "spmi-%d registered: dev:%p\n", + ctrl->nr, &ctrl->dev); + + return 0; +}; +EXPORT_SYMBOL_GPL(spmi_controller_add); + +/* Remove a device associated with a controller */ +static int spmi_ctrl_remove_device(struct device *dev, void *data) +{ + struct spmi_device *spmidev = to_spmi_device(dev); + if (dev->type == &spmi_dev_type) + spmi_device_remove(spmidev); + return 0; +} + +/** + * spmi_controller_remove(): remove an SPMI controller + * @ctrl: controller to remove + * + * Remove a SPMI controller. Caller is responsible for calling + * spmi_controller_put() to discard the allocated controller. + */ +void spmi_controller_remove(struct spmi_controller *ctrl) +{ + int dummy; + + if (!ctrl) + return; + + dummy = device_for_each_child(&ctrl->dev, NULL, + spmi_ctrl_remove_device); + device_del(&ctrl->dev); +} +EXPORT_SYMBOL_GPL(spmi_controller_remove); + +/** + * spmi_driver_register() - Register client driver with SPMI core + * @sdrv: client driver to be associated with client-device. + * + * This API will register the client driver with the SPMI framework. + * It is typically called from the driver's module-init function. + */ +int spmi_driver_register(struct spmi_driver *sdrv) +{ + sdrv->driver.bus = &spmi_bus_type; + return driver_register(&sdrv->driver); +} +EXPORT_SYMBOL_GPL(spmi_driver_register); + +static void __exit spmi_exit(void) +{ + bus_unregister(&spmi_bus_type); +} +module_exit(spmi_exit); + +static int __init spmi_init(void) +{ + return bus_register(&spmi_bus_type); +} +postcore_initcall(spmi_init); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("SPMI module"); +MODULE_ALIAS("platform:spmi"); |