Re: [RFC 5/7] Bluetooth: hci_nokia: Introduce new driver

Marcel Holtmann
2016-08-16T07:03:50Z

Hi Sebastian,

> This driver adds support for Nokia H4+ procotol used
> for example by Nokia's internet tablets (N770 - N950).
> ---
> drivers/bluetooth/Kconfig | 10 +
> drivers/bluetooth/Makefile | 1 +
> drivers/bluetooth/hci_ldisc.c | 6 +
> drivers/bluetooth/hci_nokia.c | 734 ++++++++++++++++++++++++++++++++++++++++++
> drivers/bluetooth/hci_nokia.h | 140 ++++++++
> drivers/bluetooth/hci_uart.h | 8 +-
> 6 files changed, 898 insertions(+), 1 deletion(-)
> create mode 100644 drivers/bluetooth/hci_nokia.c
> create mode 100644 drivers/bluetooth/hci_nokia.h
>
> diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
> index cf50fd2e96df..c32d9d5ad1d2 100644
> --- a/drivers/bluetooth/Kconfig
> +++ b/drivers/bluetooth/Kconfig
> @@ -86,6 +86,16 @@ config BT_HCIUART_H4
>
> Say Y here to compile support for HCI UART (H4) protocol.
>
> +config BT_HCIUART_NOKIA
> + bool "UART Nokia H4+ protocol support"
> + depends on BT_HCIUART
> + help
> + Nokia H4+ is serial protocol for communication between Bluetooth
> + device and host. This protocol is required for Bluetooth devices
> + with UART interface in Nokia devices.
> +
> + Say Y here to compile support for Nokia's H4+ protocol.
> +
> config BT_HCIUART_BCSP
> bool "BCSP protocol support"
> depends on BT_HCIUART
> diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
> index 9c18939fc5c9..f7951646ee14 100644
> --- a/drivers/bluetooth/Makefile
> +++ b/drivers/bluetooth/Makefile
> @@ -37,6 +37,7 @@ hci_uart-$(CONFIG_BT_HCIUART_INTEL) += hci_intel.o
> hci_uart-$(CONFIG_BT_HCIUART_BCM) += hci_bcm.o
> hci_uart-$(CONFIG_BT_HCIUART_QCA) += hci_qca.o
> hci_uart-$(CONFIG_BT_HCIUART_AG6XX) += hci_ag6xx.o
> +hci_uart-$(CONFIG_BT_HCIUART_NOKIA) += hci_nokia.o
> hci_uart-objs := $(hci_uart-y)
>
> ccflags-y += -D__CHECK_ENDIAN__
> diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
> index dda97398c59a..83d0de94bf35 100644
> --- a/drivers/bluetooth/hci_ldisc.c
> +++ b/drivers/bluetooth/hci_ldisc.c
> @@ -810,6 +810,9 @@ static int __init hci_uart_init(void)
> #ifdef CONFIG_BT_HCIUART_AG6XX
> ag6xx_init();
> #endif
> +#ifdef CONFIG_BT_HCIUART_NOKIA
> + nokia_init();
> +#endif
>
> return 0;
> }
> @@ -845,6 +848,9 @@ static void __exit hci_uart_exit(void)
> #ifdef CONFIG_BT_HCIUART_AG6XX
> ag6xx_deinit();
> #endif
> +#ifdef CONFIG_BT_HCIUART_NOKIA
> + nokia_deinit();
> +#endif
>
> /* Release tty registration of line discipline */
> err = tty_unregister_ldisc(N_HCI);
> diff --git a/drivers/bluetooth/hci_nokia.c b/drivers/bluetooth/hci_nokia.c
> new file mode 100644
> index 000000000000..efd4dd320838
> --- /dev/null
> +++ b/drivers/bluetooth/hci_nokia.c
> @@ -0,0 +1,734 @@
> +/*
> + *
> + * Bluetooth HCI UART H4 driver with Nokia Extensions
> + *
> + * Copyright (C) 2015 Marcel Holtmann <marcel@holtmann.org>
> + * Copyright (C) 2016 Sebastian Reichel <sre@kernel.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/module.h>
> +
> +#include <linux/clk.h>
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/types.h>
> +#include <linux/fcntl.h>
> +#include <linux/interrupt.h>
> +#include <linux/ptrace.h>
> +#include <linux/poll.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/firmware.h>
> +#include <linux/slab.h>
> +#include <linux/tty.h>
> +#include <linux/errno.h>
> +#include <linux/string.h>
> +#include <linux/signal.h>
> +#include <linux/ioctl.h>
> +#include <linux/skbuff.h>
> +#include <linux/delay.h>
> +#include <linux/platform_device.h>
> +
> +#include <linux/gpio/consumer.h>
> +
> +#include <linux/unaligned/le_struct.h>

are you sure all these includes are needed?

> +#include <net/bluetooth/bluetooth.h>
> +#include <net/bluetooth/hci_core.h>
> +
> +#include "hci_uart.h"
> +#include "hci_nokia.h"
> +
> +struct nokia_uart_dev {
> + struct device *dev;
> + struct tty_port *port;
> + struct gpio_desc *reset;
> + struct gpio_desc *wakeup_host;
> + struct gpio_desc *wakeup_bt;
> + unsigned long sysclk_speed;
> +};
> +
> +struct nokia_bt_dev {
> + struct hci_uart *hu;
> + struct nokia_uart_dev *btdata;
> + int wake_irq;
> + bool wake_state;
> + struct sk_buff *rx_skb;
> + struct sk_buff_head txq;
> + bdaddr_t bdaddr;
> +
> + int init_error;
> + struct completion init_completion;
> +
> + uint8_t man_id;
> + uint8_t ver_id;
> +};
> +
> +static char *nokia_get_fw_name(struct nokia_bt_dev *btdev)
> +{
> + switch (btdev->man_id) {
> + case NOKIA_ID_CSR:
> + return FIRMWARE_CSR;
> + case NOKIA_ID_BCM2048:
> + return FIRMWARE_BCM2048;
> + case NOKIA_ID_TI1271:
> + return FIRMWARE_TI1271;
> + default:
> + return NULL;
> + }
> +}
> +
> +static int hci_uart_wait_for_cts(struct hci_uart *hu, bool state,
> + int timeout_ms)
> +{
> + unsigned long timeout;
> + int signal;
> +
> + timeout = jiffies + msecs_to_jiffies(timeout_ms);
> + for (;;) {
> + signal = hu->tty->ops->tiocmget(hu->tty) & TIOCM_CTS;
> + if (!!signal == !!state) {
> + dev_dbg(hu->tty->dev, "wait for cts... received!\n");
> + return 0;
> + }
> + if (time_after(jiffies, timeout)) {
> + dev_dbg(hu->tty->dev, "wait for cts... timeout!\n");
> + return -ETIMEDOUT;
> + }
> + usleep_range(1000, 2000);
> + }
> +}

This is a super odd function. No return value since we essentially have an endless loop.

> +
> +static int btdev_match(struct device *child, void *data)
> +{
> + if (!strcmp(child->driver->name, "nokia-bluetooth"))
> + return 1;
> + else
> + return 0;
> +}

Anything wrong with just return !strcmp?

> +
> +static irqreturn_t wakeup_handler(int irq, void *data)
> +{
> + struct nokia_bt_dev *btdev = data;
> + struct device *serialdev = btdev->hu->tty->dev;
> + int wake_state = gpiod_get_value(btdev->btdata->wakeup_host);
> +
> + dev_dbg(serialdev, "wakeup received: %d -> %d\n",
> + btdev->wake_state, wake_state);
> +
> + if (btdev->wake_state == wake_state)
> + return IRQ_HANDLED;
> +
> + if (wake_state)
> + pm_runtime_get_sync(serialdev);
> + else if (!wake_state)
> + pm_runtime_put(serialdev);
> +
> + btdev->wake_state = wake_state;
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int nokia_reset(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> + int err;
> +
> + /* reset routine */
> + gpiod_set_value_cansleep(btdev->btdata->reset, 0);
> + gpiod_set_value_cansleep(btdev->btdata->wakeup_bt, 1);
> +
> + msleep(50);
> +
> + /* safety check */
> + err = gpiod_get_value_cansleep(btdev->btdata->wakeup_host);
> + if (err == 1) {
> + dev_err(hu->tty->dev, "reset: host wakeup not low!\n");
> + return -EPROTO;
> + }
> +
> + /* flush queues */
> + tty_ldisc_flush(hu->tty);
> + tty_driver_flush_buffer(hu->tty);
> +
> + /* init uart */
> + hci_uart_init_tty(hu);
> + hci_uart_set_flow_control(hu, true);
> + hci_uart_set_baudrate(hu, INIT_SPEED);
> +
> + gpiod_set_value_cansleep(btdev->btdata->reset, 1);
> + gpiod_set_value_cansleep(btdev->btdata->wakeup_bt, 0);
> +
> + msleep(100);
> +
> + err = gpiod_get_value_cansleep(btdev->btdata->wakeup_host);
> + if (err == 0) {
> + dev_err(hu->tty->dev, "reset: host wakeup not high!\n");
> + return -EPROTO;
> + }
> +
> + /* wait for cts */
> + err = hci_uart_wait_for_cts(hu, true, 100);
> + if (err < 0) {
> + dev_err(hu->tty->dev, "CTS not received: %d\n", err);
> + return err;
> + }
> +
> + gpiod_set_value_cansleep(btdev->btdata->wakeup_bt, 1);
> + hci_uart_set_flow_control(hu, false);
> +
> + return 0;
> +}
> +
> +static int nokia_send_alive_packet(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> + struct hci_nokia_alive_hdr *hdr;
> + struct hci_nokia_alive_pkt *pkt;
> + struct sk_buff *skb;
> + int len;
> +
> + dev_dbg(hu->tty->dev, "Sending alive packet...\n");
> +
> + init_completion(&btdev->init_completion);
> +
> + len = H4_TYPE_SIZE + sizeof(*hdr) + sizeof(*pkt);
> + skb = bt_skb_alloc(len, GFP_KERNEL);
> + if (!skb)
> + return -ENOMEM;
> +
> + hci_skb_pkt_type(skb) = HCI_NOKIA_ALIVE_PKT;
> + memset(skb->data, 0x00, len);
> +
> + hdr = (struct hci_nokia_alive_hdr *)skb_put(skb, sizeof(*hdr));
> + hdr->dlen = sizeof(*pkt);
> + pkt = (struct hci_nokia_alive_pkt *)skb_put(skb, sizeof(*pkt));
> + pkt->mid = NOKIA_ALIVE_REQ;
> +
> + hu->hdev->send(hu->hdev, skb);

I am not sure we want these to go through the Bluetooth core packet sending. They are not standard HCI packet and should stay within the driver. If you send them through the core they will cause problems with the monitor interface.

> +
> + if (!wait_for_completion_interruptible_timeout(&btdev->init_completion,
> + msecs_to_jiffies(1000))) {
> + return -ETIMEDOUT;
> + }
> +
> + if (btdev->init_error < 0)
> + return btdev->init_error;
> +
> + return 0;
> +}
> +
> +static int nokia_send_negotiation(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> + struct hci_nokia_neg_cmd *neg_cmd;
> + struct hci_nokia_neg_hdr *neg_hdr;
> + struct sk_buff *skb;
> + int len, err;
> + u16 baud = DIV_ROUND_CLOSEST(BT_BAUDRATE_DIVIDER, MAX_BAUD_RATE);
> + int sysclk = btdev->btdata->sysclk_speed / 1000;
> +
> + dev_dbg(hu->tty->dev, "Sending negotiation...\n");
> +
> + len = H4_TYPE_SIZE + sizeof(*neg_hdr) + sizeof(*neg_cmd);
> + skb = bt_skb_alloc(len, GFP_KERNEL);
> + if (!skb)
> + return -ENOMEM;
> +
> + hci_skb_pkt_type(skb) = HCI_NOKIA_NEG_PKT;
> +
> + neg_hdr = (struct hci_nokia_neg_hdr *)skb_put(skb, sizeof(*neg_hdr));
> + neg_hdr->dlen = sizeof(*neg_cmd);
> +
> + neg_cmd = (struct hci_nokia_neg_cmd *)skb_put(skb, sizeof(*neg_cmd));
> + neg_cmd->ack = NOKIA_NEG_REQ;
> + neg_cmd->baud = cpu_to_le16(baud);
> + neg_cmd->unused1 = 0x0000;
> + neg_cmd->proto = NOKIA_PROTO_BYTE;
> + neg_cmd->sys_clk = cpu_to_le16(sysclk);
> + neg_cmd->unused2 = 0x0000;
> +
> + btdev->init_error = 0;
> + init_completion(&btdev->init_completion);
> +
> + hu->hdev->send(hu->hdev, skb);
> +
> + if (!wait_for_completion_interruptible_timeout(&btdev->init_completion,
> + msecs_to_jiffies(10000))) {
> + return -ETIMEDOUT;
> + }
> +
> + if (btdev->init_error < 0)
> + return btdev->init_error;
> +
> + /* Change to operational settings */
> + hci_uart_set_flow_control(hu, true); // disable flow control

Please use a proper comment that explains also disabling flow control.
> +
> + /* setup negotiated max. baudrate */
> + hci_uart_set_baudrate(hu, MAX_BAUD_RATE);
> +
> + err = hci_uart_wait_for_cts(hu, true, 100);
> + if (err < 0)
> + return err;
> +
> + hci_uart_set_flow_control(hu, false); // re-enable flow control
> +
> + dev_dbg(hu->tty->dev, "Negotiation successful...\n");
> +
> + return 0;
> +}
> +
> +static int nokia_setup_fw(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> + const struct firmware *fw;
> + const u8 *fw_ptr;
> + size_t fw_size;
> + int err;
> +
> + BT_DBG("hu %p", hu);
> +
> + err = request_firmware(&fw, nokia_get_fw_name(btdev), hu->tty->dev);

So does this nokia_get_fw_name really needs to be a separate function? Or can this just be done right here in this function? I prefer it to be done where it is actually used. Unless you use that name in many places.

> + if (err < 0) {
> + BT_ERR("%s: Failed to load Nokia firmware file (%d)",
> + hu->hdev->name, err);
> + return err;
> + }
> +
> + fw_ptr = fw->data;
> + fw_size = fw->size;
> +
> + while (fw_size >= 4) {
> + u16 pkt_size = get_unaligned_le16(fw_ptr);
> + u8 pkt_type = fw_ptr[2];
> + const struct hci_command_hdr *cmd;
> + u16 opcode;
> + struct sk_buff *skb;
> +
> + switch (pkt_type) {
> + case HCI_COMMAND_PKT:
> + cmd = (struct hci_command_hdr *)(fw_ptr + 3);
> + opcode = le16_to_cpu(cmd->opcode);
> +
> + skb = __hci_cmd_sync(hu->hdev, opcode, cmd->plen,
> + fw_ptr + 3 + HCI_COMMAND_HDR_SIZE,
> + HCI_INIT_TIMEOUT);
> + if (IS_ERR(skb)) {
> + err = PTR_ERR(skb);
> + BT_ERR("%s: Firmware command %04x failed (%d)",
> + hu->hdev->name, opcode, err);
> + goto done;
> + }
> + kfree_skb(skb);
> + break;
> + case HCI_NOKIA_RADIO_PKT:

Are you sure you can ignore the RADIO_PKT commands. They are used to set up the FM radio parts of the chip. They are standard HCI commands (in the case of Broadcom at least). At minimum it should be added a comment here that you are ignoring them on purpose.

> + case HCI_NOKIA_NEG_PKT:
> + case HCI_NOKIA_ALIVE_PKT:

And here I would also a comment on why are we ignore these commands and driving this all by ourselves.

> + break;
> + }
> +
> + fw_ptr += pkt_size + 2;
> + fw_size -= pkt_size + 2;
> + }
> +
> +done:
> + release_firmware(fw);
> + return err;
> +}
> +
> +static int nokia_setup(struct hci_uart *hu)
> +{
> + int err;
> +
> + pm_runtime_get_sync(hu->tty->dev);
> +
> + dev_dbg(hu->tty->dev, "Nokia H4+ protocol setup...\n");
> +
> + /* 0. reset connection */
> + err = nokia_reset(hu);
> + if (err < 0) {
> + dev_err(hu->tty->dev, "Reset failed: %d\n", err);
> + goto out;
> + }
> +
> + /* 1. negotiate speed etc */
> + err = nokia_send_negotiation(hu);
> + if (err < 0) {
> + dev_err(hu->tty->dev, "Negotiation failed: %d\n", err);
> + goto out;
> + }
> +
> + /* 2. verify correct setup using alive packet */
> + err = nokia_send_alive_packet(hu);
> + if (err < 0) {
> + dev_err(hu->tty->dev, "Alive check failed: %d\n", err);
> + goto out;
> + }
> +
> + /* 3. send firmware */
> + err = nokia_setup_fw(hu);
> + if (err < 0) {
> + dev_err(hu->tty->dev, "Could not setup FW: %d\n", err);
> + goto out;
> + }
> +
> + hci_uart_set_flow_control(hu, true);
> + hci_uart_set_baudrate(hu, BC4_MAX_BAUD_RATE);

I think this variable needs a better name if it is common for all vendors.

> + hci_uart_set_flow_control(hu, false);
> +
> + dev_dbg(hu->tty->dev, "Nokia H4+ protocol setup done!\n");
> +
> + /*
> + * TODO:
> + * disable wakeup_bt at this point and automatically enable it when
> + * data is about to be written until all data has been written (+ some
> + * delay).
> + *
> + * Since this is not yet support by the uart/tty kernel framework we
> + * will always keep enabled the wakeup_bt gpio for now, so that the
> + * bluetooth chip will never transit into idle modes.
> + */
> +
> +out:
> + pm_runtime_put(hu->tty->dev);
> +
> + return err;
> +}
> +
> +static int nokia_open(struct hci_uart *hu)
> +{
> + struct device *serialdev = hu->tty->dev;
> + struct nokia_bt_dev *btdev;
> + struct device *uartbtdev;
> + int err;
> +
> + btdev = kzalloc(sizeof(*btdev), GFP_KERNEL);
> + if (!btdev)
> + return -ENOMEM;
> +
> + btdev->hu = hu;
> +
> + skb_queue_head_init(&btdev->txq);
> +
> + uartbtdev = device_find_child(serialdev, NULL, btdev_match);
> + if (!uartbtdev) {
> + dev_err(serialdev, "bluetooth device node not found!\n");
> + return -ENODEV;
> + }
> +
> + btdev->btdata = dev_get_drvdata(uartbtdev);
> + if (!btdev->btdata)
> + return -EINVAL;
> +
> + hu->priv = btdev;
> +
> + /* register handler for host wakeup gpio */
> + btdev->wake_irq = gpiod_to_irq(btdev->btdata->wakeup_host);
> + err = request_threaded_irq(btdev->wake_irq, NULL, wakeup_handler,
> + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> + "wakeup", btdev);
> + if (err) {
> + gpiod_set_value(btdev->btdata->reset, 0);
> + gpiod_set_value(btdev->btdata->wakeup_bt, 0);
> + return err;
> + }
> +
> + dev_dbg(serialdev, "Nokia H4+ protocol initialized with %s!\n",
> + dev_name(uartbtdev));
> +
> + pm_runtime_enable(hu->tty->dev);
> +
> + return 0;
> +}
> +
> +static int nokia_flush(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> +
> + BT_DBG("hu %p", hu);
> +
> + skb_queue_purge(&btdev->txq);
> +
> + return 0;
> +}
> +
> +static int nokia_close(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> +
> + hu->priv = NULL;
> +
> + BT_DBG("hu %p", hu);
> +
> + skb_queue_purge(&btdev->txq);
> +
> + kfree_skb(btdev->rx_skb);
> +
> + free_irq(btdev->wake_irq, btdev);
> +
> + /* disable module */
> + gpiod_set_value(btdev->btdata->reset, 0);
> + gpiod_set_value(btdev->btdata->wakeup_bt, 0);
> +
> + hu->priv = NULL;
> + kfree(btdev);
> +
> + pm_runtime_disable(hu->tty->dev);
> +
> + return 0;
> +}
> +
> +/* Enqueue frame for transmittion (padding, crc, etc) */
> +static int nokia_enqueue(struct hci_uart *hu, struct sk_buff *skb)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> + int err;
> +
> + BT_DBG("hu %p skb %p", hu, skb);
> +
> + /* Prepend skb with frame type */
> + memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
> +
> + /* Packets must be word aligned */
> + if (skb->len % 2) {
> + err = skb_pad(skb, 1);
> + if (err)
> + return err;
> + *skb_put(skb, 1) = 0x00;
> + }
> +
> + skb_queue_tail(&btdev->txq, skb);
> +
> + return 0;
> +}
> +
> +static int nokia_recv_negotiation_packet(struct hci_dev *hdev,
> + struct sk_buff *skb)
> +{
> + struct hci_uart *hu = hci_get_drvdata(hdev);
> + struct nokia_bt_dev *btdev = hu->priv;
> + struct hci_nokia_neg_hdr *hdr;
> + struct hci_nokia_neg_evt *evt;
> + int ret = 0;
> +
> + hdr = (struct hci_nokia_neg_hdr *)skb->data;
> + if (hdr->dlen != sizeof(*evt)) {
> + btdev->init_error = -EIO;
> + ret = -EIO;
> + goto finish_neg;
> + }
> +
> + evt = (struct hci_nokia_neg_evt *)skb_pull(skb, sizeof(*hdr));
> +
> + if (evt->ack != NOKIA_NEG_ACK) {
> + dev_err(hu->tty->dev, "Could not negotiate hci_nokia settings\n");
> + btdev->init_error = -EINVAL;
> + }
> +
> + btdev->man_id = evt->man_id;
> + btdev->ver_id = evt->ver_id;
> +
> + dev_dbg(hu->tty->dev, "NOKIA negotiation:\n");
> + dev_dbg(hu->tty->dev, "\tbaudrate = %u\n", evt->baud);
> + dev_dbg(hu->tty->dev, "\tsystem clock = %u\n", evt->sys_clk);
> + dev_dbg(hu->tty->dev, "\tmanufacturer id = %u\n", evt->man_id);
> + dev_dbg(hu->tty->dev, "\tversion id = %u\n", evt->ver_id);
> +
> +finish_neg:
> + complete(&btdev->init_completion);
> + kfree_skb(skb);
> + return ret;
> +}
> +
> +static int nokia_recv_alive_packet(struct hci_dev *hdev, struct sk_buff *skb)
> +{
> + struct hci_uart *hu = hci_get_drvdata(hdev);
> + struct nokia_bt_dev *btdev = hu->priv;
> + struct hci_nokia_alive_hdr *hdr;
> + struct hci_nokia_alive_pkt *pkt;
> + int ret = 0;
> +
> + hdr = (struct hci_nokia_alive_hdr *)skb->data;
> + if (hdr->dlen != sizeof(*pkt)) {
> + dev_err(hu->tty->dev, "Corrupted alive message\n");
> + btdev->init_error = -EIO;
> + ret = -EIO;
> + goto finish_alive;
> + }
> +
> + pkt = (struct hci_nokia_alive_pkt *)skb_pull(skb, sizeof(*hdr));
> +
> + if (pkt->mid != NOKIA_ALIVE_RESP) {
> + dev_err(hu->tty->dev, "Invalid alive response: 0x%02x!\n",
> + pkt->mid);
> + btdev->init_error = -EINVAL;
> + goto finish_alive;
> + }
> +
> + dev_dbg(hu->tty->dev, "Received alive packet!\n");
> +
> +finish_alive:
> + complete(&btdev->init_completion);
> + kfree_skb(skb);
> + return ret;
> +}
> +
> +static int nokia_recv_radio(struct hci_dev *hdev, struct sk_buff *skb)
> +{
> + /* Packets received on the dedicated radio channel are
> + * HCI events and so feed them back into the core.
> + */
> + bt_cb(skb)->pkt_type = HCI_EVENT_PKT;

I think using hci_skb_pkt_type(skb) is correct here as well.

> + return hci_recv_frame(hdev, skb);
> +}
> +
> +/* Recv data */
> +static const struct h4_recv_pkt nokia_recv_pkts[] = {
> + { NOKIA_RECV_ACL, .recv = hci_recv_frame },
> + { NOKIA_RECV_SCO, .recv = hci_recv_frame },
> + { NOKIA_RECV_EVENT, .recv = hci_recv_frame },
> + { NOKIA_RECV_ALIVE, .recv = nokia_recv_alive_packet },
> + { NOKIA_RECV_NEG, .recv = nokia_recv_negotiation_packet },
> + { NOKIA_RECV_RADIO, .recv = nokia_recv_radio },
> +};
> +
> +static int nokia_recv(struct hci_uart *hu, const void *data, int count)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> + int err;
> +
> + if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
> + return -EUNATCH;
> +
> + btdev->rx_skb = h4_recv_buf(hu->hdev, btdev->rx_skb, data, count,
> + nokia_recv_pkts, ARRAY_SIZE(nokia_recv_pkts));
> + if (IS_ERR(btdev->rx_skb)) {
> + err = PTR_ERR(btdev->rx_skb);
> + BT_ERR("%s: Frame reassembly failed (%d)", hu->hdev->name, err);
> + btdev->rx_skb = NULL;
> + return err;
> + }
> +
> + return count;
> +}
> +
> +static struct sk_buff *nokia_dequeue(struct hci_uart *hu)
> +{
> + struct nokia_bt_dev *btdev = hu->priv;
> +
> + return skb_dequeue(&btdev->txq);
> +}
> +
> +static const struct hci_uart_proto nokia_proto = {
> + .id = HCI_UART_NOKIA,
> + .name = "Nokia",
> + .open = nokia_open,
> + .close = nokia_close,
> + .recv = nokia_recv,
> + .enqueue = nokia_enqueue,
> + .dequeue = nokia_dequeue,
> + .flush = nokia_flush,
> + .setup = nokia_setup,
> +};
> +
> +static int nokia_bluetooth_probe(struct platform_device *pdev)
> +{
> + struct nokia_uart_dev *btdata;
> + struct device *bcmdev = &pdev->dev;
> + struct clk *sysclk;
> + int err = 0;
> +
> + if(!bcmdev->parent) {
> + dev_err(bcmdev, "parent device missing!\n");
> + return -ENODEV;
> + }
> +
> + btdata = devm_kmalloc(bcmdev, sizeof(*btdata), GFP_KERNEL);
> + if(!btdata)
> + return -ENOMEM;
> +
> + btdata->dev = bcmdev;
> + dev_set_drvdata(bcmdev, btdata);
> +
> + btdata->port = dev_get_drvdata(bcmdev->parent);
> + if(!btdata->port) {
> + dev_err(bcmdev, "port data missing in parent device!\n");
> + return -ENODEV;
> + }
> +
> + btdata->reset = devm_gpiod_get(bcmdev, "reset", GPIOD_OUT_LOW);
> + if (IS_ERR(btdata->reset)) {
> + err = PTR_ERR(btdata->reset);
> + dev_err(bcmdev, "could not get reset gpio: %d\n", err);
> + return err;
> + }
> +
> + btdata->wakeup_host = devm_gpiod_get(bcmdev, "host-wakeup", GPIOD_IN);
> + if (IS_ERR(btdata->wakeup_host)) {
> + err = PTR_ERR(btdata->wakeup_host);
> + dev_err(bcmdev, "could not get host wakeup gpio: %d\n", err);
> + return err;
> + }
> +
> +
> + btdata->wakeup_bt = devm_gpiod_get(bcmdev, "bluetooth-wakeup",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(btdata->wakeup_bt)) {
> + err = PTR_ERR(btdata->wakeup_bt);
> + dev_err(bcmdev, "could not get BT wakeup gpio: %d\n", err);
> + return err;
> + }
> +
> + sysclk = devm_clk_get(bcmdev, "sysclk");
> + if (IS_ERR(sysclk)) {
> + err = PTR_ERR(sysclk);
> + dev_err(bcmdev, "could not get sysclk: %d\n", err);
> + return err;
> + }
> +
> + clk_prepare_enable(sysclk);
> + btdata->sysclk_speed = clk_get_rate(sysclk);
> + clk_disable_unprepare(sysclk);
> +
> + dev_dbg(bcmdev, "parent uart: %s\n", dev_name(bcmdev->parent));
> + dev_dbg(bcmdev, "sysclk speed: %ld kHz\n", btdata->sysclk_speed / 1000);
> +
> + /* TODO: open tty and setup line disector from kernel-side */
> +
> + return err;
> +}
> +
> +static const struct of_device_id nokia_bluetooth_of_match[] = {
> + { .compatible = "nokia,brcm,bcm2048", },
> + { .compatible = "nokia,ti,wl1271-bluetooth", },

Where is the CSR BC4 one here? I prefer if we only have support for the ones that are actually supported and detected. We can easily extend things later.

> + {},
> +};
> +MODULE_DEVICE_TABLE(of, nokia_bluetooth_of_match);
> +
> +static struct platform_driver platform_nokia_driver = {
> + .driver = {
> + .name = "nokia-bluetooth",
> + .of_match_table = nokia_bluetooth_of_match,
> + },
> + .probe = nokia_bluetooth_probe,
> +};
> +
> +int __init nokia_init(void)
> +{
> + platform_driver_register(&platform_nokia_driver);
> + return hci_uart_register_proto(&nokia_proto);
> +}
> +
> +int __exit nokia_deinit(void)
> +{
> + platform_driver_unregister(&platform_nokia_driver);
> + return hci_uart_unregister_proto(&nokia_proto);
> +}
> diff --git a/drivers/bluetooth/hci_nokia.h b/drivers/bluetooth/hci_nokia.h
> new file mode 100644
> index 000000000000..8c4d307840e5
> --- /dev/null
> +++ b/drivers/bluetooth/hci_nokia.h
> @@ -0,0 +1,140 @@
> +/*
> + * Copyright (C) 2016 Sebastian Reichel <sre@kernel.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.
> + */
> +
> +#ifndef __HCI_NOKIA_H
> +#define __HCI_NOKIA_H

Lets not do a separate header here. Just move this all into hci_nokia.c. There is really zero benefit in the header.

> +
> +#define NOKIA_ID_CSR 0x02
> +#define NOKIA_ID_BCM2048 0x04
> +#define NOKIA_ID_TI1271 0x31
> +
> +#define FIRMWARE_CSR "nokia/bc4fw.bin"

If the CSR ones are not yet supported, then leave them out for now. We can add this later.

> +#define FIRMWARE_BCM2048 "nokia/bcmfw.bin"
> +#define FIRMWARE_TI1271 "nokia/ti1273.bin"
> +
> +#define NOKIA_BCM_BDADDR 0xfc01

We have btbcm.[ch] for this.

> +
> +#define HCI_NOKIA_NEG_PKT 0x06
> +#define HCI_NOKIA_ALIVE_PKT 0x07
> +#define HCI_NOKIA_RADIO_PKT 0x08
> +
> +#define HCI_NOKIA_NEG_HDR_SIZE 1
> +#define HCI_NOKIA_MAX_NEG_SIZE 255
> +#define HCI_NOKIA_ALIVE_HDR_SIZE 1
> +#define HCI_NOKIA_MAX_ALIVE_SIZE 255
> +#define HCI_NOKIA_RADIO_HDR_SIZE 2
> +#define HCI_NOKIA_MAX_RADIO_SIZE 255
> +
> +#define NOKIA_PROTO_PKT 0x44
> +#define NOKIA_PROTO_BYTE 0x4c
> +
> +#define NOKIA_NEG_REQ 0x00
> +#define NOKIA_NEG_ACK 0x20
> +#define NOKIA_NEG_NAK 0x40
> +
> +#define H4_TYPE_SIZE 1

I am not sure this define adds any overall value to the code.

> +
> +#define NOKIA_RECV_ACL \
> + H4_RECV_ACL, \
> + .wordaligned = true
> +
> +#define NOKIA_RECV_SCO \
> + H4_RECV_SCO, \
> + .wordaligned = true
> +
> +#define NOKIA_RECV_EVENT \
> + H4_RECV_EVENT, \
> + .wordaligned = true
> +
> +#define NOKIA_RECV_ALIVE \
> + .type = HCI_NOKIA_ALIVE_PKT, \
> + .hlen = HCI_NOKIA_ALIVE_HDR_SIZE, \
> + .loff = 0, \
> + .lsize = 1, \
> + .maxlen = HCI_NOKIA_MAX_ALIVE_SIZE, \
> + .wordaligned = true
> +
> +#define NOKIA_RECV_NEG \
> + .type = HCI_NOKIA_NEG_PKT, \
> + .hlen = HCI_NOKIA_NEG_HDR_SIZE, \
> + .loff = 0, \
> + .lsize = 1, \
> + .maxlen = HCI_NOKIA_MAX_NEG_SIZE, \
> + .wordaligned = true
> +
> +#define NOKIA_RECV_RADIO \
> + .type = HCI_NOKIA_RADIO_PKT, \
> + .hlen = HCI_NOKIA_RADIO_HDR_SIZE, \
> + .loff = 1, \
> + .lsize = 1, \
> + .maxlen = HCI_NOKIA_MAX_RADIO_SIZE, \
> + .wordaligned = true

For this ones I would have use the HCI event ones. My original patch had this:

+#define NOK_RECV_NEG \
+ .type = NOK_NEG_PKT, \
+ .hlen = NOK_NEG_HDR_SIZE, \
+ .loff = 0, \
+ .lsize = 1, \
+ .maxlen = HCI_MAX_EVENT_SIZE
+
+#define NOK_RECV_ALIVE \
+ .type = NOK_ALIVE_PKT, \
+ .hlen = NOK_ALIVE_HDR_SIZE, \
+ .loff = 0, \
+ .lsize = 1, \
+ .maxlen = HCI_MAX_EVENT_SIZE
+
+#define NOK_RECV_RADIO \
+ .type = NOK_RADIO_PKT, \
+ .hlen = HCI_EVENT_HDR_SIZE, \
+ .loff = 1, \
+ .lsize = 1, \
+ .maxlen = HCI_MAX_EVENT_SIZE
+
+static const struct h4_recv_pkt nok_recv_pkts[] = {
+ { H4_RECV_ACL, .recv = hci_recv_frame },
+ { H4_RECV_SCO, .recv = hci_recv_frame },
+ { H4_RECV_EVENT, .recv = hci_recv_frame },
+ { NOK_RECV_NEG, .recv = nok_recv_neg },
+ { NOK_RECV_ALIVE, .recv = nok_recv_alive },
+ { NOK_RECV_RADIO, .recv = nok_recv_radio },

With just these simple defines at the top:

+#define NOK_NEG_PKT 0x06
+#define NOK_ALIVE_PKT 0x07
+#define NOK_RADIO_PKT 0x08
+
+#define NOK_NEG_HDR_SIZE 1
+#define NOK_ALIVE_HDR_SIZE 1

And I would prefer if we keep it like that.

> +
> +struct hci_nokia_neg_hdr {
> + __u8 dlen;
> +} __packed;
> +
> +struct hci_nokia_neg_cmd {
> + __u8 ack;
> + __u16 baud;
> + __u16 unused1;
> + __u8 proto;
> + __u16 sys_clk;
> + __u16 unused2;
> +} __packed;
> +
> +static inline struct hci_nokia_neg_hdr *hci_nokia_neg_hdr(const struct sk_buff *skb)
> +{
> + return (struct hci_nokia_neg_hdr *) skb->data;
> +}

What good is this inline? A define would be way better, if really needed.

> +
> +#define NOKIA_ALIVE_REQ 0x55
> +#define NOKIA_ALIVE_RESP 0xcc
> +
> +struct hci_nokia_alive_hdr {
> + __u8 dlen;
> +} __packed;
> +
> +struct hci_nokia_alive_pkt {
> + __u8 mid;
> + __u8 unused;
> +} __packed;
> +
> +static inline struct hci_nokia_alive_hdr *hci_nokia_alive_hdr(const struct sk_buff *skb)
> +{
> + return (struct hci_nokia_alive_hdr *) skb->data;
> +}
> +
> +struct hci_nokia_neg_evt {
> + __u8 ack;
> + __u16 baud;
> + __u16 unused1;
> + __u8 proto;
> + __u16 sys_clk;
> + __u16 unused2;
> + __u8 man_id;
> + __u8 ver_id;
> +} __packed;
> +
> +#define BT_BAUDRATE_DIVIDER 384000000
> +#define BC4_MAX_BAUD_RATE 3692300
> +#define MAX_BAUD_RATE 921600
> +#define INIT_SPEED 120000
> +
> +struct hci_nokia_radio_hdr {
> + __u8 evt;
> + __u8 dlen;
> +} __packed;
> +
> +#endif
> diff --git a/drivers/bluetooth/hci_uart.h b/drivers/bluetooth/hci_uart.h
> index a7d67aec3632..314b243df996 100644
> --- a/drivers/bluetooth/hci_uart.h
> +++ b/drivers/bluetooth/hci_uart.h
> @@ -35,7 +35,7 @@
> #define HCIUARTGETFLAGS _IOR('U', 204, int)
>
> /* UART protocols */
> -#define HCI_UART_MAX_PROTO 10
> +#define HCI_UART_MAX_PROTO 11
>
> #define HCI_UART_H4 0
> #define HCI_UART_BCSP 1
> @@ -47,6 +47,7 @@
> #define HCI_UART_BCM 7
> #define HCI_UART_QCA 8
> #define HCI_UART_AG6XX 9
> +#define HCI_UART_NOKIA 10
>
> #define HCI_UART_RAW_DEVICE 0
> #define HCI_UART_RESET_ON_INIT 1
> @@ -190,3 +191,8 @@ int qca_deinit(void);
> int ag6xx_init(void);
> int ag6xx_deinit(void);
> #endif
> +
> +#ifdef CONFIG_BT_HCIUART_NOKIA
> +int nokia_init(void);
> +int nokia_deinit(void);
> +#endif

Regards

Marcel