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|
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 MediaTek Inc.
/*
* Bluetooth support for MediaTek serial devices
*
* Author: Sean Wang <sean.wang@mediatek.com>
*
*/
#include <asm/unaligned.h>
#include <linux/atomic.h>
#include <linux/clk.h>
#include <linux/firmware.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm_runtime.h>
#include <linux/serdev.h>
#include <linux/skbuff.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include "h4_recv.h"
#define VERSION "0.1"
#define FIRMWARE_MT7622 "mediatek/mt7622pr2h.bin"
#define MTK_STP_TLR_SIZE 2
#define BTMTKUART_TX_STATE_ACTIVE 1
#define BTMTKUART_TX_STATE_WAKEUP 2
#define BTMTKUART_TX_WAIT_VND_EVT 3
enum {
MTK_WMT_PATCH_DWNLD = 0x1,
MTK_WMT_FUNC_CTRL = 0x6,
MTK_WMT_RST = 0x7
};
struct mtk_stp_hdr {
u8 prefix;
__be16 dlen;
u8 cs;
} __packed;
struct mtk_wmt_hdr {
u8 dir;
u8 op;
__le16 dlen;
u8 flag;
} __packed;
struct mtk_hci_wmt_cmd {
struct mtk_wmt_hdr hdr;
u8 data[256];
} __packed;
struct btmtk_hci_wmt_params {
u8 op;
u8 flag;
u16 dlen;
const void *data;
u32 *status;
};
struct btmtkuart_dev {
struct hci_dev *hdev;
struct serdev_device *serdev;
struct clk *clk;
struct work_struct tx_work;
unsigned long tx_state;
struct sk_buff_head txq;
struct sk_buff *rx_skb;
u8 stp_pad[6];
u8 stp_cursor;
u16 stp_dlen;
};
static int mtk_hci_wmt_sync(struct hci_dev *hdev,
struct btmtk_hci_wmt_params *wmt_params)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
struct mtk_hci_wmt_cmd wc;
struct mtk_wmt_hdr *hdr;
u32 hlen;
int err;
hlen = sizeof(*hdr) + wmt_params->dlen;
if (hlen > 255)
return -EINVAL;
hdr = (struct mtk_wmt_hdr *)&wc;
hdr->dir = 1;
hdr->op = wmt_params->op;
hdr->dlen = cpu_to_le16(wmt_params->dlen + 1);
hdr->flag = wmt_params->flag;
memcpy(wc.data, wmt_params->data, wmt_params->dlen);
set_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
err = __hci_cmd_send(hdev, 0xfc6f, hlen, &wc);
if (err < 0) {
clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
return err;
}
/* The vendor specific WMT commands are all answered by a vendor
* specific event and will not have the Command Status or Command
* Complete as with usual HCI command flow control.
*
* After sending the command, wait for BTMTKUART_TX_WAIT_VND_EVT
* state to be cleared. The driver specific event receive routine
* will clear that state and with that indicate completion of the
* WMT command.
*/
err = wait_on_bit_timeout(&bdev->tx_state, BTMTKUART_TX_WAIT_VND_EVT,
TASK_INTERRUPTIBLE, HCI_INIT_TIMEOUT);
if (err == -EINTR) {
bt_dev_err(hdev, "Execution of wmt command interrupted");
clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
return err;
}
if (err) {
bt_dev_err(hdev, "Execution of wmt command timed out");
clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
return -ETIMEDOUT;
}
return 0;
}
static int mtk_setup_fw(struct hci_dev *hdev)
{
struct btmtk_hci_wmt_params wmt_params;
const struct firmware *fw;
const u8 *fw_ptr;
size_t fw_size;
int err, dlen;
u8 flag;
err = request_firmware(&fw, FIRMWARE_MT7622, &hdev->dev);
if (err < 0) {
bt_dev_err(hdev, "Failed to load firmware file (%d)", err);
return err;
}
fw_ptr = fw->data;
fw_size = fw->size;
/* The size of patch header is 30 bytes, should be skip */
if (fw_size < 30) {
err = -EINVAL;
goto free_fw;
}
fw_size -= 30;
fw_ptr += 30;
flag = 1;
wmt_params.op = MTK_WMT_PATCH_DWNLD;
wmt_params.status = NULL;
while (fw_size > 0) {
dlen = min_t(int, 250, fw_size);
/* Tell device the position in sequence */
if (fw_size - dlen <= 0)
flag = 3;
else if (fw_size < fw->size - 30)
flag = 2;
wmt_params.flag = flag;
wmt_params.dlen = dlen;
wmt_params.data = fw_ptr;
err = mtk_hci_wmt_sync(hdev, &wmt_params);
if (err < 0) {
bt_dev_err(hdev, "Failed to send wmt patch dwnld (%d)",
err);
break;
}
fw_size -= dlen;
fw_ptr += dlen;
}
free_fw:
release_firmware(fw);
return err;
}
static int btmtkuart_recv_event(struct hci_dev *hdev, struct sk_buff *skb)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
struct hci_event_hdr *hdr = (void *)skb->data;
int err;
/* Fix up the vendor event id with 0xff for vendor specific instead
* of 0xe4 so that event send via monitoring socket can be parsed
* properly.
*/
if (hdr->evt == 0xe4)
hdr->evt = HCI_EV_VENDOR;
err = hci_recv_frame(hdev, skb);
if (hdr->evt == HCI_EV_VENDOR) {
if (test_and_clear_bit(BTMTKUART_TX_WAIT_VND_EVT,
&bdev->tx_state)) {
/* Barrier to sync with other CPUs */
smp_mb__after_atomic();
wake_up_bit(&bdev->tx_state, BTMTKUART_TX_WAIT_VND_EVT);
}
}
return err;
}
static const struct h4_recv_pkt mtk_recv_pkts[] = {
{ H4_RECV_ACL, .recv = hci_recv_frame },
{ H4_RECV_SCO, .recv = hci_recv_frame },
{ H4_RECV_EVENT, .recv = btmtkuart_recv_event },
};
static void btmtkuart_tx_work(struct work_struct *work)
{
struct btmtkuart_dev *bdev = container_of(work, struct btmtkuart_dev,
tx_work);
struct serdev_device *serdev = bdev->serdev;
struct hci_dev *hdev = bdev->hdev;
while (1) {
clear_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state);
while (1) {
struct sk_buff *skb = skb_dequeue(&bdev->txq);
int len;
if (!skb)
break;
len = serdev_device_write_buf(serdev, skb->data,
skb->len);
hdev->stat.byte_tx += len;
skb_pull(skb, len);
if (skb->len > 0) {
skb_queue_head(&bdev->txq, skb);
break;
}
switch (hci_skb_pkt_type(skb)) {
case HCI_COMMAND_PKT:
hdev->stat.cmd_tx++;
break;
case HCI_ACLDATA_PKT:
hdev->stat.acl_tx++;
break;
case HCI_SCODATA_PKT:
hdev->stat.sco_tx++;
break;
}
kfree_skb(skb);
}
if (!test_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state))
break;
}
clear_bit(BTMTKUART_TX_STATE_ACTIVE, &bdev->tx_state);
}
static void btmtkuart_tx_wakeup(struct btmtkuart_dev *bdev)
{
if (test_and_set_bit(BTMTKUART_TX_STATE_ACTIVE, &bdev->tx_state))
set_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state);
schedule_work(&bdev->tx_work);
}
static const unsigned char *
mtk_stp_split(struct btmtkuart_dev *bdev, const unsigned char *data, int count,
int *sz_h4)
{
struct mtk_stp_hdr *shdr;
/* The cursor is reset when all the data of STP is consumed out */
if (!bdev->stp_dlen && bdev->stp_cursor >= 6)
bdev->stp_cursor = 0;
/* Filling pad until all STP info is obtained */
while (bdev->stp_cursor < 6 && count > 0) {
bdev->stp_pad[bdev->stp_cursor] = *data;
bdev->stp_cursor++;
data++;
count--;
}
/* Retrieve STP info and have a sanity check */
if (!bdev->stp_dlen && bdev->stp_cursor >= 6) {
shdr = (struct mtk_stp_hdr *)&bdev->stp_pad[2];
bdev->stp_dlen = be16_to_cpu(shdr->dlen) & 0x0fff;
/* Resync STP when unexpected data is being read */
if (shdr->prefix != 0x80 || bdev->stp_dlen > 2048) {
bt_dev_err(bdev->hdev, "stp format unexpect (%d, %d)",
shdr->prefix, bdev->stp_dlen);
bdev->stp_cursor = 2;
bdev->stp_dlen = 0;
}
}
/* Directly quit when there's no data found for H4 can process */
if (count <= 0)
return NULL;
/* Tranlate to how much the size of data H4 can handle so far */
*sz_h4 = min_t(int, count, bdev->stp_dlen);
/* Update the remaining size of STP packet */
bdev->stp_dlen -= *sz_h4;
/* Data points to STP payload which can be handled by H4 */
return data;
}
static int btmtkuart_recv(struct hci_dev *hdev, const u8 *data, size_t count)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
const unsigned char *p_left = data, *p_h4;
int sz_left = count, sz_h4, adv;
int err;
while (sz_left > 0) {
/* The serial data received from MT7622 BT controller is
* at all time padded around with the STP header and tailer.
*
* A full STP packet is looking like
* -----------------------------------
* | STP header | H:4 | STP tailer |
* -----------------------------------
* but it doesn't guarantee to contain a full H:4 packet which
* means that it's possible for multiple STP packets forms a
* full H:4 packet that means extra STP header + length doesn't
* indicate a full H:4 frame, things can fragment. Whose length
* recorded in STP header just shows up the most length the
* H:4 engine can handle currently.
*/
p_h4 = mtk_stp_split(bdev, p_left, sz_left, &sz_h4);
if (!p_h4)
break;
adv = p_h4 - p_left;
sz_left -= adv;
p_left += adv;
bdev->rx_skb = h4_recv_buf(bdev->hdev, bdev->rx_skb, p_h4,
sz_h4, mtk_recv_pkts,
ARRAY_SIZE(mtk_recv_pkts));
if (IS_ERR(bdev->rx_skb)) {
err = PTR_ERR(bdev->rx_skb);
bt_dev_err(bdev->hdev,
"Frame reassembly failed (%d)", err);
bdev->rx_skb = NULL;
return err;
}
sz_left -= sz_h4;
p_left += sz_h4;
}
return 0;
}
static int btmtkuart_receive_buf(struct serdev_device *serdev, const u8 *data,
size_t count)
{
struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
int err;
err = btmtkuart_recv(bdev->hdev, data, count);
if (err < 0)
return err;
bdev->hdev->stat.byte_rx += count;
return count;
}
static void btmtkuart_write_wakeup(struct serdev_device *serdev)
{
struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
btmtkuart_tx_wakeup(bdev);
}
static const struct serdev_device_ops btmtkuart_client_ops = {
.receive_buf = btmtkuart_receive_buf,
.write_wakeup = btmtkuart_write_wakeup,
};
static int btmtkuart_open(struct hci_dev *hdev)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
struct device *dev;
int err;
err = serdev_device_open(bdev->serdev);
if (err) {
bt_dev_err(hdev, "Unable to open UART device %s",
dev_name(&bdev->serdev->dev));
goto err_open;
}
bdev->stp_cursor = 2;
bdev->stp_dlen = 0;
dev = &bdev->serdev->dev;
/* Enable the power domain and clock the device requires */
pm_runtime_enable(dev);
err = pm_runtime_get_sync(dev);
if (err < 0) {
pm_runtime_put_noidle(dev);
goto err_disable_rpm;
}
err = clk_prepare_enable(bdev->clk);
if (err < 0)
goto err_put_rpm;
return 0;
err_put_rpm:
pm_runtime_put_sync(dev);
err_disable_rpm:
pm_runtime_disable(dev);
err_open:
return err;
}
static int btmtkuart_close(struct hci_dev *hdev)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
struct device *dev = &bdev->serdev->dev;
/* Shutdown the clock and power domain the device requires */
clk_disable_unprepare(bdev->clk);
pm_runtime_put_sync(dev);
pm_runtime_disable(dev);
serdev_device_close(bdev->serdev);
return 0;
}
static int btmtkuart_flush(struct hci_dev *hdev)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
/* Flush any pending characters */
serdev_device_write_flush(bdev->serdev);
skb_queue_purge(&bdev->txq);
cancel_work_sync(&bdev->tx_work);
kfree_skb(bdev->rx_skb);
bdev->rx_skb = NULL;
bdev->stp_cursor = 2;
bdev->stp_dlen = 0;
return 0;
}
static int btmtkuart_setup(struct hci_dev *hdev)
{
struct btmtk_hci_wmt_params wmt_params;
u8 param = 0x1;
int err = 0;
/* Setup a firmware which the device definitely requires */
err = mtk_setup_fw(hdev);
if (err < 0)
return err;
wmt_params.op = MTK_WMT_RST;
wmt_params.flag = 4;
wmt_params.dlen = 0;
wmt_params.data = NULL;
wmt_params.status = NULL;
/* Activate funciton the firmware providing to */
err = mtk_hci_wmt_sync(hdev, &wmt_params);
if (err < 0) {
bt_dev_err(hdev, "Failed to send wmt rst (%d)", err);
return err;
}
/* Enable Bluetooth protocol */
wmt_params.op = MTK_WMT_FUNC_CTRL;
wmt_params.flag = 0;
wmt_params.dlen = sizeof(param);
wmt_params.data = ¶m;
wmt_params.status = NULL;
err = mtk_hci_wmt_sync(hdev, &wmt_params);
if (err < 0) {
bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
return err;
}
return 0;
}
static int btmtkuart_shutdown(struct hci_dev *hdev)
{
struct btmtk_hci_wmt_params wmt_params;
u8 param = 0x0;
int err;
/* Disable the device */
wmt_params.op = MTK_WMT_FUNC_CTRL;
wmt_params.flag = 0;
wmt_params.dlen = sizeof(param);
wmt_params.data = ¶m;
wmt_params.status = NULL;
err = mtk_hci_wmt_sync(hdev, &wmt_params);
if (err < 0) {
bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
return err;
}
return 0;
}
static int btmtkuart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
{
struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
struct mtk_stp_hdr *shdr;
int err, dlen, type = 0;
/* Prepend skb with frame type */
memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
/* Make sure that there is enough rooms for STP header and trailer */
if (unlikely(skb_headroom(skb) < sizeof(*shdr)) ||
(skb_tailroom(skb) < MTK_STP_TLR_SIZE)) {
err = pskb_expand_head(skb, sizeof(*shdr), MTK_STP_TLR_SIZE,
GFP_ATOMIC);
if (err < 0)
return err;
}
/* Add the STP header */
dlen = skb->len;
shdr = skb_push(skb, sizeof(*shdr));
shdr->prefix = 0x80;
shdr->dlen = cpu_to_be16((dlen & 0x0fff) | (type << 12));
shdr->cs = 0; /* MT7622 doesn't care about checksum value */
/* Add the STP trailer */
skb_put_zero(skb, MTK_STP_TLR_SIZE);
skb_queue_tail(&bdev->txq, skb);
btmtkuart_tx_wakeup(bdev);
return 0;
}
static int btmtkuart_probe(struct serdev_device *serdev)
{
struct btmtkuart_dev *bdev;
struct hci_dev *hdev;
bdev = devm_kzalloc(&serdev->dev, sizeof(*bdev), GFP_KERNEL);
if (!bdev)
return -ENOMEM;
bdev->clk = devm_clk_get(&serdev->dev, "ref");
if (IS_ERR(bdev->clk))
return PTR_ERR(bdev->clk);
bdev->serdev = serdev;
serdev_device_set_drvdata(serdev, bdev);
serdev_device_set_client_ops(serdev, &btmtkuart_client_ops);
INIT_WORK(&bdev->tx_work, btmtkuart_tx_work);
skb_queue_head_init(&bdev->txq);
/* Initialize and register HCI device */
hdev = hci_alloc_dev();
if (!hdev) {
dev_err(&serdev->dev, "Can't allocate HCI device\n");
return -ENOMEM;
}
bdev->hdev = hdev;
hdev->bus = HCI_UART;
hci_set_drvdata(hdev, bdev);
hdev->open = btmtkuart_open;
hdev->close = btmtkuart_close;
hdev->flush = btmtkuart_flush;
hdev->setup = btmtkuart_setup;
hdev->shutdown = btmtkuart_shutdown;
hdev->send = btmtkuart_send_frame;
SET_HCIDEV_DEV(hdev, &serdev->dev);
hdev->manufacturer = 70;
set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
if (hci_register_dev(hdev) < 0) {
dev_err(&serdev->dev, "Can't register HCI device\n");
hci_free_dev(hdev);
return -ENODEV;
}
return 0;
}
static void btmtkuart_remove(struct serdev_device *serdev)
{
struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
struct hci_dev *hdev = bdev->hdev;
hci_unregister_dev(hdev);
hci_free_dev(hdev);
}
#ifdef CONFIG_OF
static const struct of_device_id mtk_of_match_table[] = {
{ .compatible = "mediatek,mt7622-bluetooth"},
{ }
};
MODULE_DEVICE_TABLE(of, mtk_of_match_table);
#endif
static struct serdev_device_driver btmtkuart_driver = {
.probe = btmtkuart_probe,
.remove = btmtkuart_remove,
.driver = {
.name = "btmtkuart",
.of_match_table = of_match_ptr(mtk_of_match_table),
},
};
module_serdev_device_driver(btmtkuart_driver);
MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
MODULE_DESCRIPTION("MediaTek Bluetooth Serial driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_FIRMWARE(FIRMWARE_MT7622);
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