Return-Path: From: To: , , , CC: , , , , , Sean Wang Subject: [PATCH v6 3/4] Bluetooth: mediatek: Add protocol support for MediaTek serial devices Date: Fri, 20 Jul 2018 13:12:29 +0800 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain List-ID: From: Sean Wang This adds a driver to run on the top of btuart 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 --- drivers/bluetooth/Kconfig | 11 + drivers/bluetooth/Makefile | 2 + drivers/bluetooth/btmtkuart.c | 552 ++++++++++++++++++++++++++++++++++++++++++ drivers/bluetooth/btmtkuart.h | 83 +++++++ 4 files changed, 648 insertions(+) create mode 100644 drivers/bluetooth/btmtkuart.c create mode 100644 drivers/bluetooth/btmtkuart.h diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig index a164ac4..074737c 100644 --- a/drivers/bluetooth/Kconfig +++ b/drivers/bluetooth/Kconfig @@ -74,6 +74,17 @@ config BT_HCIBTSDIO Say Y here to compile support for Bluetooth SDIO devices into the kernel or say M to compile it as module (btsdio). +config BT_HCIBTUART_MTK + 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_HCIUART tristate "HCI UART driver" depends on SERIAL_DEV_BUS || !SERIAL_DEV_BUS diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile index 2fb6268..2aea62e 100644 --- a/drivers/bluetooth/Makefile +++ b/drivers/bluetooth/Makefile @@ -25,6 +25,8 @@ obj-$(CONFIG_BT_BCM) += btbcm.o obj-$(CONFIG_BT_RTL) += btrtl.o obj-$(CONFIG_BT_QCA) += btqca.o +obj-$(CONFIG_BT_HCIBTUART_MTK) += btmtkuart.o + obj-$(CONFIG_BT_HCIUART_NOKIA) += hci_nokia.o btmrvl-y := btmrvl_main.o diff --git a/drivers/bluetooth/btmtkuart.c b/drivers/bluetooth/btmtkuart.c new file mode 100644 index 0000000..dd800ac --- /dev/null +++ b/drivers/bluetooth/btmtkuart.c @@ -0,0 +1,552 @@ +// 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 "btmtkuart.h" +#include "h4_recv.h" + +static void mtk_stp_reset(struct mtk_stp_splitter *sp) +{ + sp->cursor = 2; + sp->dlen = 0; +} + +static const unsigned char * +mtk_stp_split(struct mtk_btuart_dev *bdev, struct mtk_stp_splitter *sp, + 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 (!sp->dlen && sp->cursor >= 6) + sp->cursor = 0; + + /* Filling pad until all STP info is obtained. */ + while (sp->cursor < 6 && count > 0) { + sp->pad[sp->cursor] = *data; + sp->cursor++; + data++; + count--; + } + + /* Retrieve STP info and have a sanity check. */ + if (!sp->dlen && sp->cursor >= 6) { + shdr = (struct mtk_stp_hdr *)&sp->pad[2]; + sp->dlen = shdr->dlen1 << 8 | shdr->dlen2; + + /* Resync STP when unexpected data is being read. */ + if (shdr->prefix != 0x80 || sp->dlen > 2048) { + bt_dev_err(bdev->hdev, "stp format unexpect (%d, %d)", + shdr->prefix, sp->dlen); + mtk_stp_reset(sp); + } + } + + /* 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, sp->dlen); + + /* Update the remaining size of STP packet. */ + sp->dlen -= *sz_h4; + + /* Data points to STP payload which can be handled by H4. */ + return data; +} + +static int mtk_stp_send(struct mtk_btuart_dev *bdev, struct sk_buff *skb) +{ + struct mtk_stp_hdr *shdr; + struct sk_buff *new_skb; + int dlen; + + memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1); + dlen = skb->len; + + /* Make sure of STP header at least has 4-bytes free space to fill. */ + if (unlikely(skb_headroom(skb) < sizeof(*shdr))) { + new_skb = skb_realloc_headroom(skb, sizeof(*shdr)); + kfree_skb(skb); + skb = new_skb; + } + + /* Build for STP packet format. */ + shdr = skb_push(skb, sizeof(*shdr)); + mtk_make_stp_hdr(shdr, 0, dlen); + skb_put_zero(skb, MTK_STP_TLR_SIZE); + + skb_queue_tail(&bdev->txq, skb); + + return 0; +} + +static int mtk_hci_wmt_sync(struct hci_dev *hdev, u8 opcode, u8 flag, + u16 plen, const void *param) +{ + struct mtk_hci_wmt_cmd wc; + struct mtk_wmt_hdr *hdr; + struct sk_buff *skb; + u32 hlen; + + hlen = sizeof(*hdr) + plen; + if (hlen > 255) + return -EINVAL; + + hdr = (struct mtk_wmt_hdr *)&wc; + mtk_make_wmt_hdr(hdr, opcode, plen, flag); + memcpy(wc.data, param, plen); + + atomic_inc(&hdev->cmd_cnt); + + skb = __hci_cmd_sync_ev(hdev, 0xfc6f, hlen, &wc, HCI_VENDOR_PKT, + HCI_INIT_TIMEOUT); + + if (IS_ERR(skb)) { + int err = PTR_ERR(skb); + + bt_dev_err(hdev, "Failed to send wmt cmd (%d)", err); + return err; + } + + kfree_skb(skb); + + return 0; +} + +static int mtk_setup_fw(struct hci_dev *hdev) +{ + const struct firmware *fw; + const char *fwname; + const u8 *fw_ptr; + size_t fw_size; + int err, dlen; + u8 flag; + + fwname = FIRMWARE_MT7622; + + err = request_firmware(&fw, fwname, &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 deivice 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) + break; + + fw_size -= dlen; + fw_ptr += dlen; + } + + release_firmware(fw); + + return err; +} + +static int mtk_btuart_hci_frame(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct hci_event_hdr *hdr = (void *)skb->data; + + /* Fix up the vendor event id with HCI_VENDOR_PKT instead of + * 0xe4 so that btmon can parse the kind of vendor event properly. + */ + if (hdr->evt == 0xe4) + hdr->evt = HCI_VENDOR_PKT; + + /* Each HCI event would go through the core. */ + return hci_recv_frame(hdev, skb); +} + +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 = mtk_btuart_hci_frame }, +}; + +static int mtk_btuart_recv(struct hci_dev *hdev, const u8 *data, size_t count) +{ + struct mtk_btuart_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, bdev->sp, 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 void mtk_btuart_tx_work(struct work_struct *work) +{ + struct mtk_btuart_dev *bdev = container_of(work, struct mtk_btuart_dev, + tx_work); + struct serdev_device *serdev = bdev->serdev; + struct hci_dev *hdev = bdev->hdev; + + while (1) { + clear_bit(BTUART_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(BTUART_TX_STATE_WAKEUP, &bdev->tx_state)) + break; + } + + clear_bit(BTUART_TX_STATE_ACTIVE, &bdev->tx_state); +} + +static int mtk_btuart_tx_wakeup(struct mtk_btuart_dev *bdev) +{ + if (test_and_set_bit(BTUART_TX_STATE_ACTIVE, &bdev->tx_state)) { + set_bit(BTUART_TX_STATE_WAKEUP, &bdev->tx_state); + return 0; + } + + schedule_work(&bdev->tx_work); + + return 0; +} + +static int mtk_btuart_receive_buf(struct serdev_device *serdev, const u8 *data, + size_t count) +{ + struct mtk_btuart_dev *bdev = serdev_device_get_drvdata(serdev); + int err; + + err = mtk_btuart_recv(bdev->hdev, data, count); + if (err < 0) + return err; + + bdev->hdev->stat.byte_rx += count; + + return count; +} + +static void mtk_btuart_write_wakeup(struct serdev_device *serdev) +{ + struct mtk_btuart_dev *bdev = serdev_device_get_drvdata(serdev); + + mtk_btuart_tx_wakeup(bdev); +} + +static const struct serdev_device_ops mtk_btuart_client_ops = { + .receive_buf = mtk_btuart_receive_buf, + .write_wakeup = mtk_btuart_write_wakeup, +}; + +static int mtk_btuart_open(struct hci_dev *hdev) +{ + struct mtk_btuart_dev *bdev = hci_get_drvdata(hdev); + 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)); + + return err; +} + +static int mtk_btuart_close(struct hci_dev *hdev) +{ + struct mtk_btuart_dev *bdev = hci_get_drvdata(hdev); + + serdev_device_close(bdev->serdev); + + return 0; +} + +static int mtk_btuart_flush(struct hci_dev *hdev) +{ + struct mtk_btuart_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; + + return 0; +} + +static int mtk_btuart_setup(struct hci_dev *hdev) +{ + struct mtk_btuart_dev *bdev = hci_get_drvdata(hdev); + struct device *dev; + u8 param = 0x1; + int err = 0; + + dev = &bdev->serdev->dev; + + mtk_stp_reset(bdev->sp); + + /* 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; + + /* Setup a firmware which the device definitely requires. */ + err = mtk_setup_fw(hdev); + if (err < 0) + goto err_clk; + + /* Activate funciton the firmware providing to. */ + err = mtk_hci_wmt_sync(hdev, MTK_WMT_RST, 0x4, 0, 0); + if (err < 0) + goto err_clk; + + /* Enable Bluetooth protocol. */ + err = mtk_hci_wmt_sync(hdev, MTK_WMT_FUNC_CTRL, 0x0, sizeof(param), + ¶m); + if (err < 0) + goto err_clk; + + set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks); + + return 0; +err_clk: + clk_disable_unprepare(bdev->clk); +err_put_rpm: + pm_runtime_put_sync(dev); +err_disable_rpm: + pm_runtime_disable(dev); + + return err; +} + +static int mtk_btuart_shutdown(struct hci_dev *hdev) +{ + struct mtk_btuart_dev *bdev = hci_get_drvdata(hdev); + struct device *dev = &bdev->serdev->dev; + u8 param = 0x0; + + /* Disable the device. */ + mtk_hci_wmt_sync(hdev, MTK_WMT_FUNC_CTRL, 0x0, sizeof(param), ¶m); + + /* Shutdown the clock and power domain the device requires. */ + clk_disable_unprepare(bdev->clk); + pm_runtime_put_sync(dev); + pm_runtime_disable(dev); + + return 0; +} + +static int mtk_btuart_send(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct mtk_btuart_dev *bdev = hci_get_drvdata(hdev); + int err; + + err = mtk_stp_send(bdev, skb); + if (err < 0) + return err; + + err = mtk_btuart_tx_wakeup(bdev); + + return err; +} + +static int mtk_btuart_probe(struct serdev_device *serdev) +{ + struct mtk_btuart_dev *bdev; + struct hci_dev *hdev; + + bdev = devm_kzalloc(&serdev->dev, sizeof(*bdev), GFP_KERNEL); + if (!bdev) + return -ENOMEM; + + bdev->sp = devm_kzalloc(&serdev->dev, sizeof(*bdev->sp), GFP_KERNEL); + if (!bdev->sp) + 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, &mtk_btuart_client_ops); + + INIT_WORK(&bdev->tx_work, mtk_btuart_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; + hdev->manufacturer = 70; + hci_set_drvdata(hdev, bdev); + + hdev->open = mtk_btuart_open; + hdev->close = mtk_btuart_close; + hdev->flush = mtk_btuart_flush; + hdev->setup = mtk_btuart_setup; + hdev->shutdown = mtk_btuart_shutdown; + hdev->send = mtk_btuart_send; + SET_HCIDEV_DEV(hdev, &serdev->dev); + + 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 mtk_btuart_remove(struct serdev_device *serdev) +{ + struct mtk_btuart_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 mtk_btuart_driver = { + .probe = mtk_btuart_probe, + .remove = mtk_btuart_remove, + .driver = { + .name = "btmtkuart", + .of_match_table = of_match_ptr(mtk_of_match_table), + }, +}; + +module_serdev_device_driver(mtk_btuart_driver); + +MODULE_AUTHOR("Sean Wang "); +MODULE_DESCRIPTION("MediaTek Bluetooth Serial driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/bluetooth/btmtkuart.h b/drivers/bluetooth/btmtkuart.h new file mode 100644 index 0000000..b77d175 --- /dev/null +++ b/drivers/bluetooth/btmtkuart.h @@ -0,0 +1,83 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2018 MediaTek Inc. + * + * Bluetooth support for MediaTek serial devices + * + * Author: Sean Wang + * + */ + +#define FIRMWARE_MT7622 "mediatek/mt7622pr2h.bin" + +#define MTK_STP_TLR_SIZE 2 + +#define BTUART_TX_STATE_ACTIVE 1 +#define BTUART_TX_STATE_WAKEUP 2 + +enum { + MTK_WMT_PATCH_DWNLD = 0x1, + MTK_WMT_FUNC_CTRL = 0x6, + MTK_WMT_RST = 0x7 +}; + +struct mtk_stp_hdr { + u8 prefix; + u8 dlen1:4; + u8 type:4; + u8 dlen2; + 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 mtk_stp_splitter { + u8 pad[6]; + u8 cursor; + u16 dlen; +}; + +struct mtk_btuart_dev { + struct hci_dev *hdev; + struct serdev_device *serdev; + + struct work_struct tx_work; + unsigned long tx_state; + struct sk_buff_head txq; + + struct sk_buff *rx_skb; + + struct mtk_stp_splitter *sp; + struct clk *clk; +}; + +static inline void +mtk_make_stp_hdr(struct mtk_stp_hdr *hdr, u8 type, u32 dlen) +{ + u8 *p = (u8 *)hdr; + + hdr->prefix = 0x80; + hdr->dlen1 = (dlen & 0xf00) >> 8; + hdr->type = type; + hdr->dlen2 = dlen & 0xff; + hdr->cs = p[0] + p[1] + p[2]; +} + +static inline void +mtk_make_wmt_hdr(struct mtk_wmt_hdr *hdr, u8 op, u16 plen, u8 flag) +{ + hdr->dir = 1; + hdr->op = op; + hdr->dlen = cpu_to_le16(plen + 1); + hdr->flag = flag; +} -- 2.7.4