From 7237c4c9ec92e1a4f6ef1f712bf9105d7b392c6a Mon Sep 17 00:00:00 2001 From: Sean Wang Date: Wed, 8 Aug 2018 01:52:48 +0800 Subject: Bluetooth: mediatek: Add protocol support for MediaTek serial devices This adds a driver based on serdev driver for the MediaTek serial protocol based on running H:4, which can enable the built-in Bluetooth device inside MT7622 SoC. Signed-off-by: Sean Wang Signed-off-by: Marcel Holtmann --- drivers/bluetooth/Kconfig | 11 + drivers/bluetooth/Makefile | 1 + drivers/bluetooth/btmtkuart.c | 629 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 641 insertions(+) create mode 100644 drivers/bluetooth/btmtkuart.c diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig index 5f953ca8ac5b..c3736103c2ac 100644 --- a/drivers/bluetooth/Kconfig +++ b/drivers/bluetooth/Kconfig @@ -365,6 +365,17 @@ config BT_WILINK Say Y here to compile support for Texas Instrument's WiLink7 driver into the kernel or say M to compile it as module (btwilink). +config BT_MTKUART + tristate "MediaTek HCI UART driver" + depends on SERIAL_DEV_BUS + help + MediaTek Bluetooth HCI UART driver. + This driver is required if you want to use MediaTek Bluetooth + with serial interface. + + Say Y here to compile support for MediaTek Bluetooth UART devices + into the kernel or say M to compile it as module (btmtkuart). + config BT_QCOMSMD tristate "Qualcomm SMD based HCI support" depends on RPMSG || (COMPILE_TEST && RPMSG=n) diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile index ec16c55eb6e9..b7e393cfc1e3 100644 --- a/drivers/bluetooth/Makefile +++ b/drivers/bluetooth/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_BT_ATH3K) += ath3k.o obj-$(CONFIG_BT_MRVL) += btmrvl.o obj-$(CONFIG_BT_MRVL_SDIO) += btmrvl_sdio.o obj-$(CONFIG_BT_WILINK) += btwilink.o +obj-$(CONFIG_BT_MTKUART) += btmtkuart.o obj-$(CONFIG_BT_QCOMSMD) += btqcomsmd.o obj-$(CONFIG_BT_BCM) += btbcm.o obj-$(CONFIG_BT_RTL) += btrtl.o diff --git a/drivers/bluetooth/btmtkuart.c b/drivers/bluetooth/btmtkuart.c new file mode 100644 index 000000000000..e0571fe04d00 --- /dev/null +++ b/drivers/bluetooth/btmtkuart.c @@ -0,0 +1,629 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2018 MediaTek Inc. + +/* + * Bluetooth support for MediaTek serial devices + * + * Author: Sean Wang + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#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 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, u8 op, u8 flag, u16 plen, + const void *param) +{ + 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) + plen; + if (hlen > 255) + return -EINVAL; + + hdr = (struct mtk_wmt_hdr *)&wc; + hdr->dir = 1; + hdr->op = op; + hdr->dlen = cpu_to_le16(plen + 1); + hdr->flag = flag; + memcpy(wc.data, param, plen); + + 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 speicfic 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"); + return err; + } + + if (err) { + bt_dev_err(hdev, "Execution of wmt command timed out"); + return -ETIMEDOUT; + } + + return 0; +} + +static int mtk_setup_fw(struct hci_dev *hdev) +{ + 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) + return -EINVAL; + + fw_size -= 30; + fw_ptr += 30; + flag = 1; + + 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; + + err = mtk_hci_wmt_sync(hdev, MTK_WMT_PATCH_DWNLD, flag, dlen, + fw_ptr); + if (err < 0) { + bt_dev_err(hdev, "Failed to send wmt patch dwnld (%d)", + err); + break; + } + + fw_size -= dlen; + fw_ptr += dlen; + } + + 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, + sizeof(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) +{ + u8 param = 0x1; + int err = 0; + + /* Setup a firmware which the device definitely requires */ + err = mtk_setup_fw(hdev); + if (err < 0) + return err; + + /* Activate function the firmware providing to */ + err = mtk_hci_wmt_sync(hdev, MTK_WMT_RST, 0x4, 0, 0); + if (err < 0) { + bt_dev_err(hdev, "Failed to send wmt rst (%d)", err); + return err; + } + + /* Enable Bluetooth protocol */ + err = mtk_hci_wmt_sync(hdev, MTK_WMT_FUNC_CTRL, 0x0, sizeof(param), + ¶m); + 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) +{ + u8 param = 0x0; + int err; + + /* Disable the device */ + err = mtk_hci_wmt_sync(hdev, MTK_WMT_FUNC_CTRL, 0x0, sizeof(param), + ¶m); + 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 "); +MODULE_DESCRIPTION("MediaTek Bluetooth Serial driver ver " VERSION); +MODULE_VERSION(VERSION); +MODULE_LICENSE("GPL"); +MODULE_FIRMWARE(FIRMWARE_MT7622); -- cgit v1.2.3-59-g8ed1b