diff options
Diffstat (limited to 'drivers/bluetooth/hci_h5.c')
-rw-r--r-- | drivers/bluetooth/hci_h5.c | 1137 |
1 files changed, 1137 insertions, 0 deletions
diff --git a/drivers/bluetooth/hci_h5.c b/drivers/bluetooth/hci_h5.c new file mode 100644 index 0000000000..71e748a947 --- /dev/null +++ b/drivers/bluetooth/hci_h5.c @@ -0,0 +1,1137 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Bluetooth HCI Three-wire UART driver + * + * Copyright (C) 2012 Intel Corporation + */ + +#include <linux/acpi.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/kernel.h> +#include <linux/mod_devicetable.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 "btrtl.h" +#include "hci_uart.h" + +#define SUSPEND_TIMEOUT_MS 6000 + +#define HCI_3WIRE_ACK_PKT 0 +#define HCI_3WIRE_LINK_PKT 15 + +/* Sliding window size */ +#define H5_TX_WIN_MAX 4 + +#define H5_ACK_TIMEOUT msecs_to_jiffies(250) +#define H5_SYNC_TIMEOUT msecs_to_jiffies(100) + +/* + * Maximum Three-wire packet: + * 4 byte header + max value for 12-bit length + 2 bytes for CRC + */ +#define H5_MAX_LEN (4 + 0xfff + 2) + +/* Convenience macros for reading Three-wire header values */ +#define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07) +#define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07) +#define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01) +#define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01) +#define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f) +#define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4)) + +#define SLIP_DELIMITER 0xc0 +#define SLIP_ESC 0xdb +#define SLIP_ESC_DELIM 0xdc +#define SLIP_ESC_ESC 0xdd + +/* H5 state flags */ +enum { + H5_RX_ESC, /* SLIP escape mode */ + H5_TX_ACK_REQ, /* Pending ack to send */ + H5_WAKEUP_DISABLE, /* Device cannot wake host */ + H5_HW_FLOW_CONTROL, /* Use HW flow control */ +}; + +struct h5 { + /* Must be the first member, hci_serdev.c expects this. */ + struct hci_uart serdev_hu; + + struct sk_buff_head unack; /* Unack'ed packets queue */ + struct sk_buff_head rel; /* Reliable packets queue */ + struct sk_buff_head unrel; /* Unreliable packets queue */ + + unsigned long flags; + + struct sk_buff *rx_skb; /* Receive buffer */ + size_t rx_pending; /* Expecting more bytes */ + u8 rx_ack; /* Last ack number received */ + + int (*rx_func)(struct hci_uart *hu, u8 c); + + struct timer_list timer; /* Retransmission timer */ + struct hci_uart *hu; /* Parent HCI UART */ + + u8 tx_seq; /* Next seq number to send */ + u8 tx_ack; /* Next ack number to send */ + u8 tx_win; /* Sliding window size */ + + enum { + H5_UNINITIALIZED, + H5_INITIALIZED, + H5_ACTIVE, + } state; + + enum { + H5_AWAKE, + H5_SLEEPING, + H5_WAKING_UP, + } sleep; + + const struct h5_vnd *vnd; + const char *id; + + struct gpio_desc *enable_gpio; + struct gpio_desc *device_wake_gpio; +}; + +enum h5_driver_info { + H5_INFO_WAKEUP_DISABLE = BIT(0), +}; + +struct h5_vnd { + int (*setup)(struct h5 *h5); + void (*open)(struct h5 *h5); + void (*close)(struct h5 *h5); + int (*suspend)(struct h5 *h5); + int (*resume)(struct h5 *h5); + const struct acpi_gpio_mapping *acpi_gpio_map; +}; + +struct h5_device_data { + uint32_t driver_info; + struct h5_vnd *vnd; +}; + +static void h5_reset_rx(struct h5 *h5); + +static void h5_link_control(struct hci_uart *hu, const void *data, size_t len) +{ + struct h5 *h5 = hu->priv; + struct sk_buff *nskb; + + nskb = alloc_skb(3, GFP_ATOMIC); + if (!nskb) + return; + + hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT; + + skb_put_data(nskb, data, len); + + skb_queue_tail(&h5->unrel, nskb); +} + +static u8 h5_cfg_field(struct h5 *h5) +{ + /* Sliding window size (first 3 bits) */ + return h5->tx_win & 0x07; +} + +static void h5_timed_event(struct timer_list *t) +{ + const unsigned char sync_req[] = { 0x01, 0x7e }; + unsigned char conf_req[3] = { 0x03, 0xfc }; + struct h5 *h5 = from_timer(h5, t, timer); + struct hci_uart *hu = h5->hu; + struct sk_buff *skb; + unsigned long flags; + + BT_DBG("%s", hu->hdev->name); + + if (h5->state == H5_UNINITIALIZED) + h5_link_control(hu, sync_req, sizeof(sync_req)); + + if (h5->state == H5_INITIALIZED) { + conf_req[2] = h5_cfg_field(h5); + h5_link_control(hu, conf_req, sizeof(conf_req)); + } + + if (h5->state != H5_ACTIVE) { + mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); + goto wakeup; + } + + if (h5->sleep != H5_AWAKE) { + h5->sleep = H5_SLEEPING; + goto wakeup; + } + + BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen); + + spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); + + while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) { + h5->tx_seq = (h5->tx_seq - 1) & 0x07; + skb_queue_head(&h5->rel, skb); + } + + spin_unlock_irqrestore(&h5->unack.lock, flags); + +wakeup: + hci_uart_tx_wakeup(hu); +} + +static void h5_peer_reset(struct hci_uart *hu) +{ + struct h5 *h5 = hu->priv; + + bt_dev_err(hu->hdev, "Peer device has reset"); + + h5->state = H5_UNINITIALIZED; + + del_timer(&h5->timer); + + skb_queue_purge(&h5->rel); + skb_queue_purge(&h5->unrel); + skb_queue_purge(&h5->unack); + + h5->tx_seq = 0; + h5->tx_ack = 0; + + /* Send reset request to upper stack */ + hci_reset_dev(hu->hdev); +} + +static int h5_open(struct hci_uart *hu) +{ + struct h5 *h5; + const unsigned char sync[] = { 0x01, 0x7e }; + + BT_DBG("hu %p", hu); + + if (hu->serdev) { + h5 = serdev_device_get_drvdata(hu->serdev); + } else { + h5 = kzalloc(sizeof(*h5), GFP_KERNEL); + if (!h5) + return -ENOMEM; + } + + hu->priv = h5; + h5->hu = hu; + + skb_queue_head_init(&h5->unack); + skb_queue_head_init(&h5->rel); + skb_queue_head_init(&h5->unrel); + + h5_reset_rx(h5); + + timer_setup(&h5->timer, h5_timed_event, 0); + + h5->tx_win = H5_TX_WIN_MAX; + + if (h5->vnd && h5->vnd->open) + h5->vnd->open(h5); + + set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags); + + /* Send initial sync request */ + h5_link_control(hu, sync, sizeof(sync)); + mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); + + return 0; +} + +static int h5_close(struct hci_uart *hu) +{ + struct h5 *h5 = hu->priv; + + del_timer_sync(&h5->timer); + + skb_queue_purge(&h5->unack); + skb_queue_purge(&h5->rel); + skb_queue_purge(&h5->unrel); + + kfree_skb(h5->rx_skb); + h5->rx_skb = NULL; + + if (h5->vnd && h5->vnd->close) + h5->vnd->close(h5); + + if (!hu->serdev) + kfree(h5); + + return 0; +} + +static int h5_setup(struct hci_uart *hu) +{ + struct h5 *h5 = hu->priv; + + if (h5->vnd && h5->vnd->setup) + return h5->vnd->setup(h5); + + return 0; +} + +static void h5_pkt_cull(struct h5 *h5) +{ + struct sk_buff *skb, *tmp; + unsigned long flags; + int i, to_remove; + u8 seq; + + spin_lock_irqsave(&h5->unack.lock, flags); + + to_remove = skb_queue_len(&h5->unack); + if (to_remove == 0) + goto unlock; + + seq = h5->tx_seq; + + while (to_remove > 0) { + if (h5->rx_ack == seq) + break; + + to_remove--; + seq = (seq - 1) & 0x07; + } + + if (seq != h5->rx_ack) + BT_ERR("Controller acked invalid packet"); + + i = 0; + skb_queue_walk_safe(&h5->unack, skb, tmp) { + if (i++ >= to_remove) + break; + + __skb_unlink(skb, &h5->unack); + dev_kfree_skb_irq(skb); + } + + if (skb_queue_empty(&h5->unack)) + del_timer(&h5->timer); + +unlock: + spin_unlock_irqrestore(&h5->unack.lock, flags); +} + +static void h5_handle_internal_rx(struct hci_uart *hu) +{ + struct h5 *h5 = hu->priv; + const unsigned char sync_req[] = { 0x01, 0x7e }; + const unsigned char sync_rsp[] = { 0x02, 0x7d }; + unsigned char conf_req[3] = { 0x03, 0xfc }; + const unsigned char conf_rsp[] = { 0x04, 0x7b }; + const unsigned char wakeup_req[] = { 0x05, 0xfa }; + const unsigned char woken_req[] = { 0x06, 0xf9 }; + const unsigned char sleep_req[] = { 0x07, 0x78 }; + const unsigned char *hdr = h5->rx_skb->data; + const unsigned char *data = &h5->rx_skb->data[4]; + + BT_DBG("%s", hu->hdev->name); + + if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) + return; + + if (H5_HDR_LEN(hdr) < 2) + return; + + conf_req[2] = h5_cfg_field(h5); + + if (memcmp(data, sync_req, 2) == 0) { + if (h5->state == H5_ACTIVE) + h5_peer_reset(hu); + h5_link_control(hu, sync_rsp, 2); + } else if (memcmp(data, sync_rsp, 2) == 0) { + if (h5->state == H5_ACTIVE) + h5_peer_reset(hu); + h5->state = H5_INITIALIZED; + h5_link_control(hu, conf_req, 3); + } else if (memcmp(data, conf_req, 2) == 0) { + h5_link_control(hu, conf_rsp, 2); + h5_link_control(hu, conf_req, 3); + } else if (memcmp(data, conf_rsp, 2) == 0) { + if (H5_HDR_LEN(hdr) > 2) + h5->tx_win = (data[2] & 0x07); + BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win); + h5->state = H5_ACTIVE; + hci_uart_init_ready(hu); + return; + } else if (memcmp(data, sleep_req, 2) == 0) { + BT_DBG("Peer went to sleep"); + h5->sleep = H5_SLEEPING; + return; + } else if (memcmp(data, woken_req, 2) == 0) { + BT_DBG("Peer woke up"); + h5->sleep = H5_AWAKE; + } else if (memcmp(data, wakeup_req, 2) == 0) { + BT_DBG("Peer requested wakeup"); + h5_link_control(hu, woken_req, 2); + h5->sleep = H5_AWAKE; + } else { + BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]); + return; + } + + hci_uart_tx_wakeup(hu); +} + +static void h5_complete_rx_pkt(struct hci_uart *hu) +{ + struct h5 *h5 = hu->priv; + const unsigned char *hdr = h5->rx_skb->data; + + if (H5_HDR_RELIABLE(hdr)) { + h5->tx_ack = (h5->tx_ack + 1) % 8; + set_bit(H5_TX_ACK_REQ, &h5->flags); + hci_uart_tx_wakeup(hu); + } + + h5->rx_ack = H5_HDR_ACK(hdr); + + h5_pkt_cull(h5); + + switch (H5_HDR_PKT_TYPE(hdr)) { + case HCI_EVENT_PKT: + case HCI_ACLDATA_PKT: + case HCI_SCODATA_PKT: + case HCI_ISODATA_PKT: + hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr); + + /* Remove Three-wire header */ + skb_pull(h5->rx_skb, 4); + + hci_recv_frame(hu->hdev, h5->rx_skb); + h5->rx_skb = NULL; + + break; + + default: + h5_handle_internal_rx(hu); + break; + } + + h5_reset_rx(h5); +} + +static int h5_rx_crc(struct hci_uart *hu, unsigned char c) +{ + h5_complete_rx_pkt(hu); + + return 0; +} + +static int h5_rx_payload(struct hci_uart *hu, unsigned char c) +{ + struct h5 *h5 = hu->priv; + const unsigned char *hdr = h5->rx_skb->data; + + if (H5_HDR_CRC(hdr)) { + h5->rx_func = h5_rx_crc; + h5->rx_pending = 2; + } else { + h5_complete_rx_pkt(hu); + } + + return 0; +} + +static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c) +{ + struct h5 *h5 = hu->priv; + const unsigned char *hdr = h5->rx_skb->data; + + BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u", + hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), + H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), + H5_HDR_LEN(hdr)); + + if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) { + bt_dev_err(hu->hdev, "Invalid header checksum"); + h5_reset_rx(h5); + return 0; + } + + if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) { + bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)", + H5_HDR_SEQ(hdr), h5->tx_ack); + set_bit(H5_TX_ACK_REQ, &h5->flags); + hci_uart_tx_wakeup(hu); + h5_reset_rx(h5); + return 0; + } + + if (h5->state != H5_ACTIVE && + H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) { + bt_dev_err(hu->hdev, "Non-link packet received in non-active state"); + h5_reset_rx(h5); + return 0; + } + + h5->rx_func = h5_rx_payload; + h5->rx_pending = H5_HDR_LEN(hdr); + + return 0; +} + +static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c) +{ + struct h5 *h5 = hu->priv; + + if (c == SLIP_DELIMITER) + return 1; + + h5->rx_func = h5_rx_3wire_hdr; + h5->rx_pending = 4; + + h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC); + if (!h5->rx_skb) { + bt_dev_err(hu->hdev, "Can't allocate mem for new packet"); + h5_reset_rx(h5); + return -ENOMEM; + } + + h5->rx_skb->dev = (void *)hu->hdev; + + return 0; +} + +static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c) +{ + struct h5 *h5 = hu->priv; + + if (c == SLIP_DELIMITER) + h5->rx_func = h5_rx_pkt_start; + + return 1; +} + +static void h5_unslip_one_byte(struct h5 *h5, unsigned char c) +{ + const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC; + const u8 *byte = &c; + + if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) { + set_bit(H5_RX_ESC, &h5->flags); + return; + } + + if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) { + switch (c) { + case SLIP_ESC_DELIM: + byte = &delim; + break; + case SLIP_ESC_ESC: + byte = &esc; + break; + default: + BT_ERR("Invalid esc byte 0x%02hhx", c); + h5_reset_rx(h5); + return; + } + } + + skb_put_data(h5->rx_skb, byte, 1); + h5->rx_pending--; + + BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending); +} + +static void h5_reset_rx(struct h5 *h5) +{ + if (h5->rx_skb) { + kfree_skb(h5->rx_skb); + h5->rx_skb = NULL; + } + + h5->rx_func = h5_rx_delimiter; + h5->rx_pending = 0; + clear_bit(H5_RX_ESC, &h5->flags); +} + +static int h5_recv(struct hci_uart *hu, const void *data, int count) +{ + struct h5 *h5 = hu->priv; + const unsigned char *ptr = data; + + BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending, + count); + + while (count > 0) { + int processed; + + if (h5->rx_pending > 0) { + if (*ptr == SLIP_DELIMITER) { + bt_dev_err(hu->hdev, "Too short H5 packet"); + h5_reset_rx(h5); + continue; + } + + h5_unslip_one_byte(h5, *ptr); + + ptr++; count--; + continue; + } + + processed = h5->rx_func(hu, *ptr); + if (processed < 0) + return processed; + + ptr += processed; + count -= processed; + } + + if (hu->serdev) { + pm_runtime_get(&hu->serdev->dev); + pm_runtime_mark_last_busy(&hu->serdev->dev); + pm_runtime_put_autosuspend(&hu->serdev->dev); + } + + return 0; +} + +static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) +{ + struct h5 *h5 = hu->priv; + + if (skb->len > 0xfff) { + bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len); + kfree_skb(skb); + return 0; + } + + if (h5->state != H5_ACTIVE) { + bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state"); + kfree_skb(skb); + return 0; + } + + switch (hci_skb_pkt_type(skb)) { + case HCI_ACLDATA_PKT: + case HCI_COMMAND_PKT: + skb_queue_tail(&h5->rel, skb); + break; + + case HCI_SCODATA_PKT: + case HCI_ISODATA_PKT: + skb_queue_tail(&h5->unrel, skb); + break; + + default: + bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb)); + kfree_skb(skb); + break; + } + + if (hu->serdev) { + pm_runtime_get_sync(&hu->serdev->dev); + pm_runtime_mark_last_busy(&hu->serdev->dev); + pm_runtime_put_autosuspend(&hu->serdev->dev); + } + + return 0; +} + +static void h5_slip_delim(struct sk_buff *skb) +{ + const char delim = SLIP_DELIMITER; + + skb_put_data(skb, &delim, 1); +} + +static void h5_slip_one_byte(struct sk_buff *skb, u8 c) +{ + const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM }; + const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC }; + + switch (c) { + case SLIP_DELIMITER: + skb_put_data(skb, &esc_delim, 2); + break; + case SLIP_ESC: + skb_put_data(skb, &esc_esc, 2); + break; + default: + skb_put_data(skb, &c, 1); + } +} + +static bool valid_packet_type(u8 type) +{ + switch (type) { + case HCI_ACLDATA_PKT: + case HCI_COMMAND_PKT: + case HCI_SCODATA_PKT: + case HCI_ISODATA_PKT: + case HCI_3WIRE_LINK_PKT: + case HCI_3WIRE_ACK_PKT: + return true; + default: + return false; + } +} + +static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type, + const u8 *data, size_t len) +{ + struct h5 *h5 = hu->priv; + struct sk_buff *nskb; + u8 hdr[4]; + int i; + + if (!valid_packet_type(pkt_type)) { + bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type); + return NULL; + } + + /* + * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2 + * (because bytes 0xc0 and 0xdb are escaped, worst case is when + * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0 + * delimiters at start and end). + */ + nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC); + if (!nskb) + return NULL; + + hci_skb_pkt_type(nskb) = pkt_type; + + h5_slip_delim(nskb); + + hdr[0] = h5->tx_ack << 3; + clear_bit(H5_TX_ACK_REQ, &h5->flags); + + /* Reliable packet? */ + if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) { + hdr[0] |= 1 << 7; + hdr[0] |= h5->tx_seq; + h5->tx_seq = (h5->tx_seq + 1) % 8; + } + + hdr[1] = pkt_type | ((len & 0x0f) << 4); + hdr[2] = len >> 4; + hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff); + + BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u", + hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), + H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), + H5_HDR_LEN(hdr)); + + for (i = 0; i < 4; i++) + h5_slip_one_byte(nskb, hdr[i]); + + for (i = 0; i < len; i++) + h5_slip_one_byte(nskb, data[i]); + + h5_slip_delim(nskb); + + return nskb; +} + +static struct sk_buff *h5_dequeue(struct hci_uart *hu) +{ + struct h5 *h5 = hu->priv; + unsigned long flags; + struct sk_buff *skb, *nskb; + + if (h5->sleep != H5_AWAKE) { + const unsigned char wakeup_req[] = { 0x05, 0xfa }; + + if (h5->sleep == H5_WAKING_UP) + return NULL; + + h5->sleep = H5_WAKING_UP; + BT_DBG("Sending wakeup request"); + + mod_timer(&h5->timer, jiffies + HZ / 100); + return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2); + } + + skb = skb_dequeue(&h5->unrel); + if (skb) { + nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), + skb->data, skb->len); + if (nskb) { + kfree_skb(skb); + return nskb; + } + + skb_queue_head(&h5->unrel, skb); + bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed"); + } + + spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); + + if (h5->unack.qlen >= h5->tx_win) + goto unlock; + + skb = skb_dequeue(&h5->rel); + if (skb) { + nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), + skb->data, skb->len); + if (nskb) { + __skb_queue_tail(&h5->unack, skb); + mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT); + spin_unlock_irqrestore(&h5->unack.lock, flags); + return nskb; + } + + skb_queue_head(&h5->rel, skb); + bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed"); + } + +unlock: + spin_unlock_irqrestore(&h5->unack.lock, flags); + + if (test_bit(H5_TX_ACK_REQ, &h5->flags)) + return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0); + + return NULL; +} + +static int h5_flush(struct hci_uart *hu) +{ + BT_DBG("hu %p", hu); + return 0; +} + +static const struct hci_uart_proto h5p = { + .id = HCI_UART_3WIRE, + .name = "Three-wire (H5)", + .open = h5_open, + .close = h5_close, + .setup = h5_setup, + .recv = h5_recv, + .enqueue = h5_enqueue, + .dequeue = h5_dequeue, + .flush = h5_flush, +}; + +static int h5_serdev_probe(struct serdev_device *serdev) +{ + struct device *dev = &serdev->dev; + struct h5 *h5; + const struct h5_device_data *data; + + h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL); + if (!h5) + return -ENOMEM; + + h5->hu = &h5->serdev_hu; + h5->serdev_hu.serdev = serdev; + serdev_device_set_drvdata(serdev, h5); + + if (has_acpi_companion(dev)) { + const struct acpi_device_id *match; + + match = acpi_match_device(dev->driver->acpi_match_table, dev); + if (!match) + return -ENODEV; + + data = (const struct h5_device_data *)match->driver_data; + h5->vnd = data->vnd; + h5->id = (char *)match->id; + + if (h5->vnd->acpi_gpio_map) + devm_acpi_dev_add_driver_gpios(dev, + h5->vnd->acpi_gpio_map); + } else { + data = of_device_get_match_data(dev); + if (!data) + return -ENODEV; + + h5->vnd = data->vnd; + } + + if (data->driver_info & H5_INFO_WAKEUP_DISABLE) + set_bit(H5_WAKEUP_DISABLE, &h5->flags); + + h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW); + if (IS_ERR(h5->enable_gpio)) + return PTR_ERR(h5->enable_gpio); + + h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake", + GPIOD_OUT_LOW); + if (IS_ERR(h5->device_wake_gpio)) + return PTR_ERR(h5->device_wake_gpio); + + return hci_uart_register_device(&h5->serdev_hu, &h5p); +} + +static void h5_serdev_remove(struct serdev_device *serdev) +{ + struct h5 *h5 = serdev_device_get_drvdata(serdev); + + hci_uart_unregister_device(&h5->serdev_hu); +} + +static int __maybe_unused h5_serdev_suspend(struct device *dev) +{ + struct h5 *h5 = dev_get_drvdata(dev); + int ret = 0; + + if (h5->vnd && h5->vnd->suspend) + ret = h5->vnd->suspend(h5); + + return ret; +} + +static int __maybe_unused h5_serdev_resume(struct device *dev) +{ + struct h5 *h5 = dev_get_drvdata(dev); + int ret = 0; + + if (h5->vnd && h5->vnd->resume) + ret = h5->vnd->resume(h5); + + return ret; +} + +#ifdef CONFIG_BT_HCIUART_RTL +static int h5_btrtl_setup(struct h5 *h5) +{ + struct btrtl_device_info *btrtl_dev; + struct sk_buff *skb; + __le32 baudrate_data; + u32 device_baudrate; + unsigned int controller_baudrate; + bool flow_control; + int err; + + btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id); + if (IS_ERR(btrtl_dev)) + return PTR_ERR(btrtl_dev); + + err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev, + &controller_baudrate, &device_baudrate, + &flow_control); + if (err) + goto out_free; + + baudrate_data = cpu_to_le32(device_baudrate); + skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data), + &baudrate_data, HCI_INIT_TIMEOUT); + if (IS_ERR(skb)) { + rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n"); + err = PTR_ERR(skb); + goto out_free; + } else { + kfree_skb(skb); + } + /* Give the device some time to set up the new baudrate. */ + usleep_range(10000, 20000); + + serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate); + serdev_device_set_flow_control(h5->hu->serdev, flow_control); + + if (flow_control) + set_bit(H5_HW_FLOW_CONTROL, &h5->flags); + + err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev); + /* Give the device some time before the hci-core sends it a reset */ + usleep_range(10000, 20000); + if (err) + goto out_free; + + btrtl_set_quirks(h5->hu->hdev, btrtl_dev); + +out_free: + btrtl_free(btrtl_dev); + + return err; +} + +static void h5_btrtl_open(struct h5 *h5) +{ + /* + * Since h5_btrtl_resume() does a device_reprobe() the suspend handling + * done by the hci_suspend_notifier is not necessary; it actually causes + * delays and a bunch of errors to get logged, so disable it. + */ + if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) + set_bit(HCI_UART_NO_SUSPEND_NOTIFIER, &h5->hu->flags); + + /* Devices always start with these fixed parameters */ + serdev_device_set_flow_control(h5->hu->serdev, false); + serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN); + serdev_device_set_baudrate(h5->hu->serdev, 115200); + + if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) { + pm_runtime_set_active(&h5->hu->serdev->dev); + pm_runtime_use_autosuspend(&h5->hu->serdev->dev); + pm_runtime_set_autosuspend_delay(&h5->hu->serdev->dev, + SUSPEND_TIMEOUT_MS); + pm_runtime_enable(&h5->hu->serdev->dev); + } + + /* The controller needs reset to startup */ + gpiod_set_value_cansleep(h5->enable_gpio, 0); + gpiod_set_value_cansleep(h5->device_wake_gpio, 0); + msleep(100); + + /* The controller needs up to 500ms to wakeup */ + gpiod_set_value_cansleep(h5->enable_gpio, 1); + gpiod_set_value_cansleep(h5->device_wake_gpio, 1); + msleep(500); +} + +static void h5_btrtl_close(struct h5 *h5) +{ + if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) + pm_runtime_disable(&h5->hu->serdev->dev); + + gpiod_set_value_cansleep(h5->device_wake_gpio, 0); + gpiod_set_value_cansleep(h5->enable_gpio, 0); +} + +/* Suspend/resume support. On many devices the RTL BT device loses power during + * suspend/resume, causing it to lose its firmware and all state. So we simply + * turn it off on suspend and reprobe on resume. This mirrors how RTL devices + * are handled in the USB driver, where the BTUSB_WAKEUP_DISABLE is used which + * also causes a reprobe on resume. + */ +static int h5_btrtl_suspend(struct h5 *h5) +{ + serdev_device_set_flow_control(h5->hu->serdev, false); + gpiod_set_value_cansleep(h5->device_wake_gpio, 0); + + if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) + gpiod_set_value_cansleep(h5->enable_gpio, 0); + + return 0; +} + +struct h5_btrtl_reprobe { + struct device *dev; + struct work_struct work; +}; + +static void h5_btrtl_reprobe_worker(struct work_struct *work) +{ + struct h5_btrtl_reprobe *reprobe = + container_of(work, struct h5_btrtl_reprobe, work); + int ret; + + ret = device_reprobe(reprobe->dev); + if (ret && ret != -EPROBE_DEFER) + dev_err(reprobe->dev, "Reprobe error %d\n", ret); + + put_device(reprobe->dev); + kfree(reprobe); + module_put(THIS_MODULE); +} + +static int h5_btrtl_resume(struct h5 *h5) +{ + if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) { + struct h5_btrtl_reprobe *reprobe; + + reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL); + if (!reprobe) + return -ENOMEM; + + __module_get(THIS_MODULE); + + INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker); + reprobe->dev = get_device(&h5->hu->serdev->dev); + queue_work(system_long_wq, &reprobe->work); + } else { + gpiod_set_value_cansleep(h5->device_wake_gpio, 1); + + if (test_bit(H5_HW_FLOW_CONTROL, &h5->flags)) + serdev_device_set_flow_control(h5->hu->serdev, true); + } + + return 0; +} + +static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false }; +static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false }; +static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false }; +static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = { + { "device-wake-gpios", &btrtl_device_wake_gpios, 1 }, + { "enable-gpios", &btrtl_enable_gpios, 1 }, + { "host-wake-gpios", &btrtl_host_wake_gpios, 1 }, + {}, +}; + +static struct h5_vnd rtl_vnd = { + .setup = h5_btrtl_setup, + .open = h5_btrtl_open, + .close = h5_btrtl_close, + .suspend = h5_btrtl_suspend, + .resume = h5_btrtl_resume, + .acpi_gpio_map = acpi_btrtl_gpios, +}; + +static const struct h5_device_data h5_data_rtl8822cs = { + .vnd = &rtl_vnd, +}; + +static const struct h5_device_data h5_data_rtl8723bs = { + .driver_info = H5_INFO_WAKEUP_DISABLE, + .vnd = &rtl_vnd, +}; +#endif + +#ifdef CONFIG_ACPI +static const struct acpi_device_id h5_acpi_match[] = { +#ifdef CONFIG_BT_HCIUART_RTL + { "OBDA0623", (kernel_ulong_t)&h5_data_rtl8723bs }, + { "OBDA8723", (kernel_ulong_t)&h5_data_rtl8723bs }, +#endif + { }, +}; +MODULE_DEVICE_TABLE(acpi, h5_acpi_match); +#endif + +static const struct dev_pm_ops h5_serdev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume) + SET_RUNTIME_PM_OPS(h5_serdev_suspend, h5_serdev_resume, NULL) +}; + +static const struct of_device_id rtl_bluetooth_of_match[] = { +#ifdef CONFIG_BT_HCIUART_RTL + { .compatible = "realtek,rtl8822cs-bt", + .data = (const void *)&h5_data_rtl8822cs }, + { .compatible = "realtek,rtl8723bs-bt", + .data = (const void *)&h5_data_rtl8723bs }, + { .compatible = "realtek,rtl8723cs-bt", + .data = (const void *)&h5_data_rtl8723bs }, + { .compatible = "realtek,rtl8723ds-bt", + .data = (const void *)&h5_data_rtl8723bs }, +#endif + { }, +}; +MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match); + +static struct serdev_device_driver h5_serdev_driver = { + .probe = h5_serdev_probe, + .remove = h5_serdev_remove, + .driver = { + .name = "hci_uart_h5", + .acpi_match_table = ACPI_PTR(h5_acpi_match), + .pm = &h5_serdev_pm_ops, + .of_match_table = rtl_bluetooth_of_match, + }, +}; + +int __init h5_init(void) +{ + serdev_device_driver_register(&h5_serdev_driver); + return hci_uart_register_proto(&h5p); +} + +int __exit h5_deinit(void) +{ + serdev_device_driver_unregister(&h5_serdev_driver); + return hci_uart_unregister_proto(&h5p); +} |