drivers/bluetooth/hci_ath.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Atheros Communication Bluetooth HCIATH3K UART protocol
   4  *
   5  *  HCIATH3K (HCI Atheros AR300x Protocol) is a Atheros Communication's
   6  *  power management protocol extension to H4 to support AR300x Bluetooth Chip.
   7  *
   8  *  Copyright (c) 2009-2010 Atheros Communications Inc.
   9  *
  10  *  Acknowledgements:
  11  *  This file is based on hci_h4.c, which was written
  12  *  by Maxim Krasnyansky and Marcel Holtmann.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17
  18 #include <linux/init.h>
  19 #include <linux/slab.h>
  20 #include <linux/tty.h>
  21 #include <linux/errno.h>
  22 #include <linux/ioctl.h>
  23 #include <linux/skbuff.h>
  24
  25 #include <net/bluetooth/bluetooth.h>
  26 #include <net/bluetooth/hci_core.h>
  27
  28 #include "hci_uart.h"
  29
  30 struct ath_struct {
  31         struct hci_uart *hu;
  32         unsigned int cur_sleep;
  33
  34         struct sk_buff *rx_skb;
  35         struct sk_buff_head txq;
  36         struct work_struct ctxtsw;
  37 };
  38
  39 #define OP_WRITE_TAG    0x01
  40
  41 #define INDEX_BDADDR    0x01
  42
  43 struct ath_vendor_cmd {
  44         __u8 opcode;
  45         __le16 index;
  46         __u8 len;
  47         __u8 data[251];
  48 } __packed;
  49
  50 static int ath_wakeup_ar3k(struct tty_struct *tty)
  51 {
  52         int status = tty->driver->ops->tiocmget(tty);
  53
  54         if (status & TIOCM_CTS)
  55                 return status;
  56
  57         /* Clear RTS first */
  58         tty->driver->ops->tiocmget(tty);
  59         tty->driver->ops->tiocmset(tty, 0x00, TIOCM_RTS);
  60         msleep(20);
  61
  62         /* Set RTS, wake up board */
  63         tty->driver->ops->tiocmget(tty);
  64         tty->driver->ops->tiocmset(tty, TIOCM_RTS, 0x00);
  65         msleep(20);
  66
  67         status = tty->driver->ops->tiocmget(tty);
  68         return status;
  69 }
  70
  71 static void ath_hci_uart_work(struct work_struct *work)
  72 {
  73         int status;
  74         struct ath_struct *ath;
  75         struct hci_uart *hu;
  76         struct tty_struct *tty;
  77
  78         ath = container_of(work, struct ath_struct, ctxtsw);
  79
  80         hu = ath->hu;
  81         tty = hu->tty;
  82
  83         /* verify and wake up controller */
  84         if (ath->cur_sleep) {
  85                 status = ath_wakeup_ar3k(tty);
  86                 if (!(status & TIOCM_CTS))
  87                         return;
  88         }
  89
  90         /* Ready to send Data */
  91         clear_bit(HCI_UART_SENDING, &hu->tx_state);
  92         hci_uart_tx_wakeup(hu);
  93 }
  94
  95 static int ath_open(struct hci_uart *hu)
  96 {
  97         struct ath_struct *ath;
  98
  99         BT_DBG("hu %p", hu);
 100
 101         ath = kzalloc(sizeof(*ath), GFP_KERNEL);
 102         if (!ath)
 103                 return -ENOMEM;
 104
 105         skb_queue_head_init(&ath->txq);
 106
 107         hu->priv = ath;
 108         ath->hu = hu;
 109
 110         INIT_WORK(&ath->ctxtsw, ath_hci_uart_work);
 111
 112         return 0;
 113 }
 114
 115 static int ath_close(struct hci_uart *hu)
 116 {
 117         struct ath_struct *ath = hu->priv;
 118
 119         BT_DBG("hu %p", hu);
 120
 121         skb_queue_purge(&ath->txq);
 122
 123         kfree_skb(ath->rx_skb);
 124
 125         cancel_work_sync(&ath->ctxtsw);
 126
 127         hu->priv = NULL;
 128         kfree(ath);
 129
 130         return 0;
 131 }
 132
 133 static int ath_flush(struct hci_uart *hu)
 134 {
 135         struct ath_struct *ath = hu->priv;
 136
 137         BT_DBG("hu %p", hu);
 138
 139         skb_queue_purge(&ath->txq);
 140
 141         return 0;
 142 }
 143
 144 static int ath_vendor_cmd(struct hci_dev *hdev, uint8_t opcode, uint16_t index,
 145                           const void *data, size_t dlen)
 146 {
 147         struct sk_buff *skb;
 148         struct ath_vendor_cmd cmd;
 149
 150         if (dlen > sizeof(cmd.data))
 151                 return -EINVAL;
 152
 153         cmd.opcode = opcode;
 154         cmd.index = cpu_to_le16(index);
 155         cmd.len = dlen;
 156         memcpy(cmd.data, data, dlen);
 157
 158         skb = __hci_cmd_sync(hdev, 0xfc0b, dlen + 4, &cmd, HCI_INIT_TIMEOUT);
 159         if (IS_ERR(skb))
 160                 return PTR_ERR(skb);
 161         kfree_skb(skb);
 162
 163         return 0;
 164 }
 165
 166 static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
 167 {
 168         return ath_vendor_cmd(hdev, OP_WRITE_TAG, INDEX_BDADDR, bdaddr,
 169                               sizeof(*bdaddr));
 170 }
 171
 172 static int ath_setup(struct hci_uart *hu)
 173 {
 174         BT_DBG("hu %p", hu);
 175
 176         hu->hdev->set_bdaddr = ath_set_bdaddr;
 177
 178         return 0;
 179 }
 180
 181 static const struct h4_recv_pkt ath_recv_pkts[] = {
 182         { H4_RECV_ACL,   .recv = hci_recv_frame },
 183         { H4_RECV_SCO,   .recv = hci_recv_frame },
 184         { H4_RECV_EVENT, .recv = hci_recv_frame },
 185 };
 186
 187 static int ath_recv(struct hci_uart *hu, const void *data, int count)
 188 {
 189         struct ath_struct *ath = hu->priv;
 190
 191         ath->rx_skb = h4_recv_buf(hu->hdev, ath->rx_skb, data, count,
 192                                   ath_recv_pkts, ARRAY_SIZE(ath_recv_pkts));
 193         if (IS_ERR(ath->rx_skb)) {
 194                 int err = PTR_ERR(ath->rx_skb);
 195                 bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
 196                 ath->rx_skb = NULL;
 197                 return err;
 198         }
 199
 200         return count;
 201 }
 202
 203 #define HCI_OP_ATH_SLEEP 0xFC04
 204
 205 static int ath_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 206 {
 207         struct ath_struct *ath = hu->priv;
 208
 209         if (hci_skb_pkt_type(skb) == HCI_SCODATA_PKT) {
 210                 kfree_skb(skb);
 211                 return 0;
 212         }
 213
 214         /* Update power management enable flag with parameters of
 215          * HCI sleep enable vendor specific HCI command.
 216          */
 217         if (hci_skb_pkt_type(skb) == HCI_COMMAND_PKT) {
 218                 struct hci_command_hdr *hdr = (void *)skb->data;
 219
 220                 if (__le16_to_cpu(hdr->opcode) == HCI_OP_ATH_SLEEP)
 221                         ath->cur_sleep = skb->data[HCI_COMMAND_HDR_SIZE];
 222         }
 223
 224         BT_DBG("hu %p skb %p", hu, skb);
 225
 226         /* Prepend skb with frame type */
 227         memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
 228
 229         skb_queue_tail(&ath->txq, skb);
 230         set_bit(HCI_UART_SENDING, &hu->tx_state);
 231
 232         schedule_work(&ath->ctxtsw);
 233
 234         return 0;
 235 }
 236
 237 static struct sk_buff *ath_dequeue(struct hci_uart *hu)
 238 {
 239         struct ath_struct *ath = hu->priv;
 240
 241         return skb_dequeue(&ath->txq);
 242 }
 243
 244 static const struct hci_uart_proto athp = {
 245         .id             = HCI_UART_ATH3K,
 246         .name           = "ATH3K",
 247         .manufacturer   = 69,
 248         .open           = ath_open,
 249         .close          = ath_close,
 250         .flush          = ath_flush,
 251         .setup          = ath_setup,
 252         .recv           = ath_recv,
 253         .enqueue        = ath_enqueue,
 254         .dequeue        = ath_dequeue,
 255 };
 256
 257 int __init ath_init(void)
 258 {
 259         return hci_uart_register_proto(&athp);
 260 }
 261
 262 int __exit ath_deinit(void)
 263 {
 264         return hci_uart_unregister_proto(&athp);
 265 }