diff options
Diffstat (limited to 'drivers/bluetooth/hci_serdev.c')
-rw-r--r-- | drivers/bluetooth/hci_serdev.c | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/drivers/bluetooth/hci_serdev.c b/drivers/bluetooth/hci_serdev.c new file mode 100644 index 000000000..9ebcf0d9e --- /dev/null +++ b/drivers/bluetooth/hci_serdev.c @@ -0,0 +1,384 @@ +/* + * Bluetooth HCI serdev driver lib + * + * Copyright (C) 2017 Linaro, Ltd., Rob Herring <robh@kernel.org> + * + * Based on hci_ldisc.c: + * + * Copyright (C) 2000-2001 Qualcomm Incorporated + * Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com> + * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/serdev.h> +#include <linux/skbuff.h> + +#include <net/bluetooth/bluetooth.h> +#include <net/bluetooth/hci_core.h> + +#include "hci_uart.h" + +static struct serdev_device_ops hci_serdev_client_ops; + +static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type) +{ + struct hci_dev *hdev = hu->hdev; + + /* Update HCI stat counters */ + switch (pkt_type) { + 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; + } +} + +static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu) +{ + struct sk_buff *skb = hu->tx_skb; + + if (!skb) + skb = hu->proto->dequeue(hu); + else + hu->tx_skb = NULL; + + return skb; +} + +static void hci_uart_write_work(struct work_struct *work) +{ + struct hci_uart *hu = container_of(work, struct hci_uart, write_work); + struct serdev_device *serdev = hu->serdev; + struct hci_dev *hdev = hu->hdev; + struct sk_buff *skb; + + /* REVISIT: + * should we cope with bad skbs or ->write() returning an error value? + */ + do { + clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state); + + while ((skb = hci_uart_dequeue(hu))) { + int len; + + len = serdev_device_write_buf(serdev, + skb->data, skb->len); + hdev->stat.byte_tx += len; + + skb_pull(skb, len); + if (skb->len) { + hu->tx_skb = skb; + break; + } + + hci_uart_tx_complete(hu, hci_skb_pkt_type(skb)); + kfree_skb(skb); + } + } while(test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state)); + + clear_bit(HCI_UART_SENDING, &hu->tx_state); +} + +/* ------- Interface to HCI layer ------ */ + +/* Reset device */ +static int hci_uart_flush(struct hci_dev *hdev) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + + BT_DBG("hdev %p serdev %p", hdev, hu->serdev); + + if (hu->tx_skb) { + kfree_skb(hu->tx_skb); hu->tx_skb = NULL; + } + + /* Flush any pending characters in the driver and discipline. */ + serdev_device_write_flush(hu->serdev); + + if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) + hu->proto->flush(hu); + + return 0; +} + +/* Initialize device */ +static int hci_uart_open(struct hci_dev *hdev) +{ + BT_DBG("%s %p", hdev->name, hdev); + + /* Undo clearing this from hci_uart_close() */ + hdev->flush = hci_uart_flush; + + return 0; +} + +/* Close device */ +static int hci_uart_close(struct hci_dev *hdev) +{ + BT_DBG("hdev %p", hdev); + + hci_uart_flush(hdev); + hdev->flush = NULL; + + return 0; +} + +/* Send frames from HCI layer */ +static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + + BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb), + skb->len); + + hu->proto->enqueue(hu, skb); + + hci_uart_tx_wakeup(hu); + + return 0; +} + +static int hci_uart_setup(struct hci_dev *hdev) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + struct hci_rp_read_local_version *ver; + struct sk_buff *skb; + unsigned int speed; + int err; + + /* Init speed if any */ + if (hu->init_speed) + speed = hu->init_speed; + else if (hu->proto->init_speed) + speed = hu->proto->init_speed; + else + speed = 0; + + if (speed) + serdev_device_set_baudrate(hu->serdev, speed); + + /* Operational speed if any */ + if (hu->oper_speed) + speed = hu->oper_speed; + else if (hu->proto->oper_speed) + speed = hu->proto->oper_speed; + else + speed = 0; + + if (hu->proto->set_baudrate && speed) { + err = hu->proto->set_baudrate(hu, speed); + if (err) + bt_dev_err(hdev, "Failed to set baudrate"); + else + serdev_device_set_baudrate(hu->serdev, speed); + } + + if (hu->proto->setup) + return hu->proto->setup(hu); + + if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags)) + return 0; + + skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL, + HCI_INIT_TIMEOUT); + if (IS_ERR(skb)) { + bt_dev_err(hdev, "Reading local version info failed (%ld)", + PTR_ERR(skb)); + return 0; + } + + if (skb->len != sizeof(*ver)) + bt_dev_err(hdev, "Event length mismatch for version info"); + + kfree_skb(skb); + return 0; +} + +/** hci_uart_write_wakeup - transmit buffer wakeup + * @serdev: serial device + * + * This function is called by the serdev framework when it accepts + * more data being sent. + */ +static void hci_uart_write_wakeup(struct serdev_device *serdev) +{ + struct hci_uart *hu = serdev_device_get_drvdata(serdev); + + BT_DBG(""); + + if (!hu || serdev != hu->serdev) { + WARN_ON(1); + return; + } + + if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) + hci_uart_tx_wakeup(hu); +} + +/** hci_uart_receive_buf - receive buffer wakeup + * @serdev: serial device + * @data: pointer to received data + * @count: count of received data in bytes + * + * This function is called by the serdev framework when it received data + * in the RX buffer. + * + * Return: number of processed bytes + */ +static int hci_uart_receive_buf(struct serdev_device *serdev, const u8 *data, + size_t count) +{ + struct hci_uart *hu = serdev_device_get_drvdata(serdev); + + if (!hu || serdev != hu->serdev) { + WARN_ON(1); + return 0; + } + + if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) + return 0; + + /* It does not need a lock here as it is already protected by a mutex in + * tty caller + */ + hu->proto->recv(hu, data, count); + + if (hu->hdev) + hu->hdev->stat.byte_rx += count; + + return count; +} + +static struct serdev_device_ops hci_serdev_client_ops = { + .receive_buf = hci_uart_receive_buf, + .write_wakeup = hci_uart_write_wakeup, +}; + +int hci_uart_register_device(struct hci_uart *hu, + const struct hci_uart_proto *p) +{ + int err; + struct hci_dev *hdev; + + BT_DBG(""); + + serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops); + + err = serdev_device_open(hu->serdev); + if (err) + return err; + + percpu_init_rwsem(&hu->proto_lock); + + err = p->open(hu); + if (err) + goto err_open; + + hu->proto = p; + set_bit(HCI_UART_PROTO_READY, &hu->flags); + + /* Initialize and register HCI device */ + hdev = hci_alloc_dev(); + if (!hdev) { + BT_ERR("Can't allocate HCI device"); + err = -ENOMEM; + goto err_alloc; + } + + hu->hdev = hdev; + + hdev->bus = HCI_UART; + hci_set_drvdata(hdev, hu); + + INIT_WORK(&hu->init_ready, hci_uart_init_work); + INIT_WORK(&hu->write_work, hci_uart_write_work); + + /* Only when vendor specific setup callback is provided, consider + * the manufacturer information valid. This avoids filling in the + * value for Ericsson when nothing is specified. + */ + if (hu->proto->setup) + hdev->manufacturer = hu->proto->manufacturer; + + hdev->open = hci_uart_open; + hdev->close = hci_uart_close; + hdev->flush = hci_uart_flush; + hdev->send = hci_uart_send_frame; + hdev->setup = hci_uart_setup; + SET_HCIDEV_DEV(hdev, &hu->serdev->dev); + + if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags)) + set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks); + + if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags)) + set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks); + + if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags)) + set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks); + + if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags)) + hdev->dev_type = HCI_AMP; + else + hdev->dev_type = HCI_PRIMARY; + + if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags)) + return 0; + + if (hci_register_dev(hdev) < 0) { + BT_ERR("Can't register HCI device"); + err = -ENODEV; + goto err_register; + } + + set_bit(HCI_UART_REGISTERED, &hu->flags); + + return 0; + +err_register: + hci_free_dev(hdev); +err_alloc: + clear_bit(HCI_UART_PROTO_READY, &hu->flags); + p->close(hu); +err_open: + serdev_device_close(hu->serdev); + return err; +} +EXPORT_SYMBOL_GPL(hci_uart_register_device); + +void hci_uart_unregister_device(struct hci_uart *hu) +{ + struct hci_dev *hdev = hu->hdev; + + clear_bit(HCI_UART_PROTO_READY, &hu->flags); + + cancel_work_sync(&hu->init_ready); + if (test_bit(HCI_UART_REGISTERED, &hu->flags)) + hci_unregister_dev(hdev); + hci_free_dev(hdev); + + cancel_work_sync(&hu->write_work); + + hu->proto->close(hu); + serdev_device_close(hu->serdev); +} +EXPORT_SYMBOL_GPL(hci_uart_unregister_device); |