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 if (!hci_uart_has_flow_control(hu)) 102 return -EOPNOTSUPP; 103 104 ath = kzalloc(sizeof(*ath), GFP_KERNEL); 105 if (!ath) 106 return -ENOMEM; 107 108 skb_queue_head_init(&ath->txq); 109 110 hu->priv = ath; 111 ath->hu = hu; 112 113 INIT_WORK(&ath->ctxtsw, ath_hci_uart_work); 114 115 return 0; 116 } 117 118 static int ath_close(struct hci_uart *hu) 119 { 120 struct ath_struct *ath = hu->priv; 121 122 BT_DBG("hu %p", hu); 123 124 skb_queue_purge(&ath->txq); 125 126 kfree_skb(ath->rx_skb); 127 128 cancel_work_sync(&ath->ctxtsw); 129 130 hu->priv = NULL; 131 kfree(ath); 132 133 return 0; 134 } 135 136 static int ath_flush(struct hci_uart *hu) 137 { 138 struct ath_struct *ath = hu->priv; 139 140 BT_DBG("hu %p", hu); 141 142 skb_queue_purge(&ath->txq); 143 144 return 0; 145 } 146 147 static int ath_vendor_cmd(struct hci_dev *hdev, uint8_t opcode, uint16_t index, 148 const void *data, size_t dlen) 149 { 150 struct sk_buff *skb; 151 struct ath_vendor_cmd cmd; 152 153 if (dlen > sizeof(cmd.data)) 154 return -EINVAL; 155 156 cmd.opcode = opcode; 157 cmd.index = cpu_to_le16(index); 158 cmd.len = dlen; 159 memcpy(cmd.data, data, dlen); 160 161 skb = __hci_cmd_sync(hdev, 0xfc0b, dlen + 4, &cmd, HCI_INIT_TIMEOUT); 162 if (IS_ERR(skb)) 163 return PTR_ERR(skb); 164 kfree_skb(skb); 165 166 return 0; 167 } 168 169 static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr) 170 { 171 return ath_vendor_cmd(hdev, OP_WRITE_TAG, INDEX_BDADDR, bdaddr, 172 sizeof(*bdaddr)); 173 } 174 175 static int ath_setup(struct hci_uart *hu) 176 { 177 BT_DBG("hu %p", hu); 178 179 hu->hdev->set_bdaddr = ath_set_bdaddr; 180 181 return 0; 182 } 183 184 static const struct h4_recv_pkt ath_recv_pkts[] = { 185 { H4_RECV_ACL, .recv = hci_recv_frame }, 186 { H4_RECV_SCO, .recv = hci_recv_frame }, 187 { H4_RECV_EVENT, .recv = hci_recv_frame }, 188 }; 189 190 static int ath_recv(struct hci_uart *hu, const void *data, int count) 191 { 192 struct ath_struct *ath = hu->priv; 193 194 ath->rx_skb = h4_recv_buf(hu->hdev, ath->rx_skb, data, count, 195 ath_recv_pkts, ARRAY_SIZE(ath_recv_pkts)); 196 if (IS_ERR(ath->rx_skb)) { 197 int err = PTR_ERR(ath->rx_skb); 198 bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err); 199 ath->rx_skb = NULL; 200 return err; 201 } 202 203 return count; 204 } 205 206 #define HCI_OP_ATH_SLEEP 0xFC04 207 208 static int ath_enqueue(struct hci_uart *hu, struct sk_buff *skb) 209 { 210 struct ath_struct *ath = hu->priv; 211 212 if (hci_skb_pkt_type(skb) == HCI_SCODATA_PKT) { 213 kfree_skb(skb); 214 return 0; 215 } 216 217 /* Update power management enable flag with parameters of 218 * HCI sleep enable vendor specific HCI command. 219 */ 220 if (hci_skb_pkt_type(skb) == HCI_COMMAND_PKT) { 221 struct hci_command_hdr *hdr = (void *)skb->data; 222 223 if (__le16_to_cpu(hdr->opcode) == HCI_OP_ATH_SLEEP) 224 ath->cur_sleep = skb->data[HCI_COMMAND_HDR_SIZE]; 225 } 226 227 BT_DBG("hu %p skb %p", hu, skb); 228 229 /* Prepend skb with frame type */ 230 memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1); 231 232 skb_queue_tail(&ath->txq, skb); 233 set_bit(HCI_UART_SENDING, &hu->tx_state); 234 235 schedule_work(&ath->ctxtsw); 236 237 return 0; 238 } 239 240 static struct sk_buff *ath_dequeue(struct hci_uart *hu) 241 { 242 struct ath_struct *ath = hu->priv; 243 244 return skb_dequeue(&ath->txq); 245 } 246 247 static const struct hci_uart_proto athp = { 248 .id = HCI_UART_ATH3K, 249 .name = "ATH3K", 250 .manufacturer = 69, 251 .open = ath_open, 252 .close = ath_close, 253 .flush = ath_flush, 254 .setup = ath_setup, 255 .recv = ath_recv, 256 .enqueue = ath_enqueue, 257 .dequeue = ath_dequeue, 258 }; 259 260 int __init ath_init(void) 261 { 262 return hci_uart_register_proto(&athp); 263 } 264 265 int __exit ath_deinit(void) 266 { 267 return hci_uart_unregister_proto(&athp); 268 } 269