Bluetooth: hci_bcm: Add support for MINIX Z83-4 based devices

[mirror_ubuntu-bionic-kernel.git] / drivers / bluetooth / hci_bcm.c

/*
 *
 *  Bluetooth HCI UART driver for Broadcom devices
 *
 *  Copyright (C) 2015  Intel Corporation
 *
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/firmware.h>
#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/gpio/consumer.h>
#include <linux/tty.h>
#include <linux/interrupt.h>
#include <linux/dmi.h>
#include <linux/pm_runtime.h>
#include <linux/serdev.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#include "btbcm.h"
#include "hci_uart.h"

#define BCM_NULL_PKT 0x00
#define BCM_NULL_SIZE 0

#define BCM_LM_DIAG_PKT 0x07
#define BCM_LM_DIAG_SIZE 63

#define BCM_AUTOSUSPEND_DELAY   5000 /* default autosleep delay */

/* device driver resources */
struct bcm_device {
        /* Must be the first member, hci_serdev.c expects this. */
        struct hci_uart         serdev_hu;
        struct list_head        list;

        struct device           *dev;

        const char              *name;
        struct gpio_desc        *device_wakeup;
        struct gpio_desc        *shutdown;

        struct clk              *clk;
        bool                    clk_enabled;

        u32                     init_speed;
        u32                     oper_speed;
        int                     irq;
        bool                    irq_active_low;

#ifdef CONFIG_PM
        struct hci_uart         *hu;
        bool                    is_suspended; /* suspend/resume flag */
#endif
};

/* generic bcm uart resources */
struct bcm_data {
        struct sk_buff          *rx_skb;
        struct sk_buff_head     txq;

        struct bcm_device       *dev;
};

/* List of BCM BT UART devices */
static DEFINE_MUTEX(bcm_device_lock);
static LIST_HEAD(bcm_device_list);

static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed)
{
        if (hu->serdev)
                serdev_device_set_baudrate(hu->serdev, speed);
        else
                hci_uart_set_baudrate(hu, speed);
}

static int bcm_set_baudrate(struct hci_uart *hu, unsigned int speed)
{
        struct hci_dev *hdev = hu->hdev;
        struct sk_buff *skb;
        struct bcm_update_uart_baud_rate param;

        if (speed > 3000000) {
                struct bcm_write_uart_clock_setting clock;

                clock.type = BCM_UART_CLOCK_48MHZ;

                bt_dev_dbg(hdev, "Set Controller clock (%d)", clock.type);

                /* This Broadcom specific command changes the UART's controller
                 * clock for baud rate > 3000000.
                 */
                skb = __hci_cmd_sync(hdev, 0xfc45, 1, &clock, HCI_INIT_TIMEOUT);
                if (IS_ERR(skb)) {
                        int err = PTR_ERR(skb);
                        bt_dev_err(hdev, "BCM: failed to write clock (%d)",
                                   err);
                        return err;
                }

                kfree_skb(skb);
        }

        bt_dev_dbg(hdev, "Set Controller UART speed to %d bit/s", speed);

        param.zero = cpu_to_le16(0);
        param.baud_rate = cpu_to_le32(speed);

        /* This Broadcom specific command changes the UART's controller baud
         * rate.
         */
        skb = __hci_cmd_sync(hdev, 0xfc18, sizeof(param), &param,
                             HCI_INIT_TIMEOUT);
        if (IS_ERR(skb)) {
                int err = PTR_ERR(skb);
                bt_dev_err(hdev, "BCM: failed to write update baudrate (%d)",
                           err);
                return err;
        }

        kfree_skb(skb);

        return 0;
}

/* bcm_device_exists should be protected by bcm_device_lock */
static bool bcm_device_exists(struct bcm_device *device)
{
        struct list_head *p;

        /* Devices using serdev always exist */
        if (device && device->hu && device->hu->serdev)
                return true;

        list_for_each(p, &bcm_device_list) {
                struct bcm_device *dev = list_entry(p, struct bcm_device, list);

                if (device == dev)
                        return true;
        }

        return false;
}

static int bcm_gpio_set_power(struct bcm_device *dev, bool powered)
{
        if (powered && !IS_ERR(dev->clk) && !dev->clk_enabled)
                clk_prepare_enable(dev->clk);

        gpiod_set_value(dev->shutdown, powered);
        gpiod_set_value(dev->device_wakeup, powered);

        if (!powered && !IS_ERR(dev->clk) && dev->clk_enabled)
                clk_disable_unprepare(dev->clk);

        dev->clk_enabled = powered;

        return 0;
}

#ifdef CONFIG_PM
static irqreturn_t bcm_host_wake(int irq, void *data)
{
        struct bcm_device *bdev = data;

        bt_dev_dbg(bdev, "Host wake IRQ");

        pm_runtime_get(bdev->dev);
        pm_runtime_mark_last_busy(bdev->dev);
        pm_runtime_put_autosuspend(bdev->dev);

        return IRQ_HANDLED;
}

static int bcm_request_irq(struct bcm_data *bcm)
{
        struct bcm_device *bdev = bcm->dev;
        int err;

        mutex_lock(&bcm_device_lock);
        if (!bcm_device_exists(bdev)) {
                err = -ENODEV;
                goto unlock;
        }

        if (bdev->irq <= 0) {
                err = -EOPNOTSUPP;
                goto unlock;
        }

        err = devm_request_irq(bdev->dev, bdev->irq, bcm_host_wake,
                               bdev->irq_active_low ? IRQF_TRIGGER_FALLING :
                                                      IRQF_TRIGGER_RISING,
                               "host_wake", bdev);
        if (err)
                goto unlock;

        device_init_wakeup(bdev->dev, true);

        pm_runtime_set_autosuspend_delay(bdev->dev,
                                         BCM_AUTOSUSPEND_DELAY);
        pm_runtime_use_autosuspend(bdev->dev);
        pm_runtime_set_active(bdev->dev);
        pm_runtime_enable(bdev->dev);

unlock:
        mutex_unlock(&bcm_device_lock);

        return err;
}

static const struct bcm_set_sleep_mode default_sleep_params = {
        .sleep_mode = 1,        /* 0=Disabled, 1=UART, 2=Reserved, 3=USB */
        .idle_host = 2,         /* idle threshold HOST, in 300ms */
        .idle_dev = 2,          /* idle threshold device, in 300ms */
        .bt_wake_active = 1,    /* BT_WAKE active mode: 1 = high, 0 = low */
        .host_wake_active = 0,  /* HOST_WAKE active mode: 1 = high, 0 = low */
        .allow_host_sleep = 1,  /* Allow host sleep in SCO flag */
        .combine_modes = 1,     /* Combine sleep and LPM flag */
        .tristate_control = 0,  /* Allow tri-state control of UART tx flag */
        /* Irrelevant USB flags */
        .usb_auto_sleep = 0,
        .usb_resume_timeout = 0,
        .pulsed_host_wake = 0,
        .break_to_host = 0
};

static int bcm_setup_sleep(struct hci_uart *hu)
{
        struct bcm_data *bcm = hu->priv;
        struct sk_buff *skb;
        struct bcm_set_sleep_mode sleep_params = default_sleep_params;

        sleep_params.host_wake_active = !bcm->dev->irq_active_low;

        skb = __hci_cmd_sync(hu->hdev, 0xfc27, sizeof(sleep_params),
                             &sleep_params, HCI_INIT_TIMEOUT);
        if (IS_ERR(skb)) {
                int err = PTR_ERR(skb);
                bt_dev_err(hu->hdev, "Sleep VSC failed (%d)", err);
                return err;
        }
        kfree_skb(skb);

        bt_dev_dbg(hu->hdev, "Set Sleep Parameters VSC succeeded");

        return 0;
}
#else
static inline int bcm_request_irq(struct bcm_data *bcm) { return 0; }
static inline int bcm_setup_sleep(struct hci_uart *hu) { return 0; }
#endif

static int bcm_set_diag(struct hci_dev *hdev, bool enable)
{
        struct hci_uart *hu = hci_get_drvdata(hdev);
        struct bcm_data *bcm = hu->priv;
        struct sk_buff *skb;

        if (!test_bit(HCI_RUNNING, &hdev->flags))
                return -ENETDOWN;

        skb = bt_skb_alloc(3, GFP_KERNEL);
        if (!skb)
                return -ENOMEM;

        skb_put_u8(skb, BCM_LM_DIAG_PKT);
        skb_put_u8(skb, 0xf0);
        skb_put_u8(skb, enable);

        skb_queue_tail(&bcm->txq, skb);
        hci_uart_tx_wakeup(hu);

        return 0;
}

static int bcm_open(struct hci_uart *hu)
{
        struct bcm_data *bcm;
        struct list_head *p;

        bt_dev_dbg(hu->hdev, "hu %p", hu);

        bcm = kzalloc(sizeof(*bcm), GFP_KERNEL);
        if (!bcm)
                return -ENOMEM;

        skb_queue_head_init(&bcm->txq);

        hu->priv = bcm;

        mutex_lock(&bcm_device_lock);

        if (hu->serdev) {
                serdev_device_open(hu->serdev);
                bcm->dev = serdev_device_get_drvdata(hu->serdev);
                goto out;
        }

        if (!hu->tty->dev)
                goto out;

        list_for_each(p, &bcm_device_list) {
                struct bcm_device *dev = list_entry(p, struct bcm_device, list);

                /* Retrieve saved bcm_device based on parent of the
                 * platform device (saved during device probe) and
                 * parent of tty device used by hci_uart
                 */
                if (hu->tty->dev->parent == dev->dev->parent) {
                        bcm->dev = dev;
#ifdef CONFIG_PM
                        dev->hu = hu;
#endif
                        break;
                }
        }

out:
        if (bcm->dev) {
                hu->init_speed = bcm->dev->init_speed;
                hu->oper_speed = bcm->dev->oper_speed;
                bcm_gpio_set_power(bcm->dev, true);
        }

        mutex_unlock(&bcm_device_lock);
        return 0;
}

static int bcm_close(struct hci_uart *hu)
{
        struct bcm_data *bcm = hu->priv;
        struct bcm_device *bdev = NULL;

        bt_dev_dbg(hu->hdev, "hu %p", hu);

        /* Protect bcm->dev against removal of the device or driver */
        mutex_lock(&bcm_device_lock);

        if (hu->serdev) {
                serdev_device_close(hu->serdev);
                bdev = serdev_device_get_drvdata(hu->serdev);
        } else if (bcm_device_exists(bcm->dev)) {
                bdev = bcm->dev;
#ifdef CONFIG_PM
                bdev->hu = NULL;
#endif
        }

        if (bdev) {
                bcm_gpio_set_power(bdev, false);
#ifdef CONFIG_PM
                pm_runtime_disable(bdev->dev);
                pm_runtime_set_suspended(bdev->dev);

                if (device_can_wakeup(bdev->dev)) {
                        devm_free_irq(bdev->dev, bdev->irq, bdev);
                        device_init_wakeup(bdev->dev, false);
                }
#endif
        }
        mutex_unlock(&bcm_device_lock);

        skb_queue_purge(&bcm->txq);
        kfree_skb(bcm->rx_skb);
        kfree(bcm);

        hu->priv = NULL;
        return 0;
}

static int bcm_flush(struct hci_uart *hu)
{
        struct bcm_data *bcm = hu->priv;

        bt_dev_dbg(hu->hdev, "hu %p", hu);

        skb_queue_purge(&bcm->txq);

        return 0;
}

static int bcm_setup(struct hci_uart *hu)
{
        struct bcm_data *bcm = hu->priv;
        char fw_name[64];
        const struct firmware *fw;
        unsigned int speed;
        int err;

        bt_dev_dbg(hu->hdev, "hu %p", hu);

        hu->hdev->set_diag = bcm_set_diag;
        hu->hdev->set_bdaddr = btbcm_set_bdaddr;

        err = btbcm_initialize(hu->hdev, fw_name, sizeof(fw_name));
        if (err)
                return err;

        err = request_firmware(&fw, fw_name, &hu->hdev->dev);
        if (err < 0) {
                bt_dev_info(hu->hdev, "BCM: Patch %s not found", fw_name);
                return 0;
        }

        err = btbcm_patchram(hu->hdev, fw);
        if (err) {
                bt_dev_info(hu->hdev, "BCM: Patch failed (%d)", err);
                goto finalize;
        }

        /* 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)
                host_set_baudrate(hu, 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 (speed) {
                err = bcm_set_baudrate(hu, speed);
                if (!err)
                        host_set_baudrate(hu, speed);
        }

finalize:
        release_firmware(fw);

        err = btbcm_finalize(hu->hdev);
        if (err)
                return err;

        if (!bcm_request_irq(bcm))
                err = bcm_setup_sleep(hu);

        return err;
}

#define BCM_RECV_LM_DIAG \
        .type = BCM_LM_DIAG_PKT, \
        .hlen = BCM_LM_DIAG_SIZE, \
        .loff = 0, \
        .lsize = 0, \
        .maxlen = BCM_LM_DIAG_SIZE

#define BCM_RECV_NULL \
        .type = BCM_NULL_PKT, \
        .hlen = BCM_NULL_SIZE, \
        .loff = 0, \
        .lsize = 0, \
        .maxlen = BCM_NULL_SIZE

static const struct h4_recv_pkt bcm_recv_pkts[] = {
        { H4_RECV_ACL,      .recv = hci_recv_frame },
        { H4_RECV_SCO,      .recv = hci_recv_frame },
        { H4_RECV_EVENT,    .recv = hci_recv_frame },
        { BCM_RECV_LM_DIAG, .recv = hci_recv_diag  },
        { BCM_RECV_NULL,    .recv = hci_recv_diag  },
};

static int bcm_recv(struct hci_uart *hu, const void *data, int count)
{
        struct bcm_data *bcm = hu->priv;

        if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
                return -EUNATCH;

        bcm->rx_skb = h4_recv_buf(hu->hdev, bcm->rx_skb, data, count,
                                  bcm_recv_pkts, ARRAY_SIZE(bcm_recv_pkts));
        if (IS_ERR(bcm->rx_skb)) {
                int err = PTR_ERR(bcm->rx_skb);
                bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
                bcm->rx_skb = NULL;
                return err;
        } else if (!bcm->rx_skb) {
                /* Delay auto-suspend when receiving completed packet */
                mutex_lock(&bcm_device_lock);
                if (bcm->dev && bcm_device_exists(bcm->dev)) {
                        pm_runtime_get(bcm->dev->dev);
                        pm_runtime_mark_last_busy(bcm->dev->dev);
                        pm_runtime_put_autosuspend(bcm->dev->dev);
                }
                mutex_unlock(&bcm_device_lock);
        }

        return count;
}

static int bcm_enqueue(struct hci_uart *hu, struct sk_buff *skb)
{
        struct bcm_data *bcm = hu->priv;

        bt_dev_dbg(hu->hdev, "hu %p skb %p", hu, skb);

        /* Prepend skb with frame type */
        memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
        skb_queue_tail(&bcm->txq, skb);

        return 0;
}

static struct sk_buff *bcm_dequeue(struct hci_uart *hu)
{
        struct bcm_data *bcm = hu->priv;
        struct sk_buff *skb = NULL;
        struct bcm_device *bdev = NULL;

        mutex_lock(&bcm_device_lock);

        if (bcm_device_exists(bcm->dev)) {
                bdev = bcm->dev;
                pm_runtime_get_sync(bdev->dev);
                /* Shall be resumed here */
        }

        skb = skb_dequeue(&bcm->txq);

        if (bdev) {
                pm_runtime_mark_last_busy(bdev->dev);
                pm_runtime_put_autosuspend(bdev->dev);
        }

        mutex_unlock(&bcm_device_lock);

        return skb;
}

#ifdef CONFIG_PM
static int bcm_suspend_device(struct device *dev)
{
        struct bcm_device *bdev = dev_get_drvdata(dev);

        bt_dev_dbg(bdev, "");

        if (!bdev->is_suspended && bdev->hu) {
                hci_uart_set_flow_control(bdev->hu, true);

                /* Once this returns, driver suspends BT via GPIO */
                bdev->is_suspended = true;
        }

        /* Suspend the device */
        if (bdev->device_wakeup) {
                gpiod_set_value(bdev->device_wakeup, false);
                bt_dev_dbg(bdev, "suspend, delaying 15 ms");
                mdelay(15);
        }

        return 0;
}

static int bcm_resume_device(struct device *dev)
{
        struct bcm_device *bdev = dev_get_drvdata(dev);

        bt_dev_dbg(bdev, "");

        if (bdev->device_wakeup) {
                gpiod_set_value(bdev->device_wakeup, true);
                bt_dev_dbg(bdev, "resume, delaying 15 ms");
                mdelay(15);
        }

        /* When this executes, the device has woken up already */
        if (bdev->is_suspended && bdev->hu) {
                bdev->is_suspended = false;

                hci_uart_set_flow_control(bdev->hu, false);
        }

        return 0;
}
#endif

#ifdef CONFIG_PM_SLEEP
/* suspend callback */
static int bcm_suspend(struct device *dev)
{
        struct bcm_device *bdev = dev_get_drvdata(dev);
        int error;

        bt_dev_dbg(bdev, "suspend: is_suspended %d", bdev->is_suspended);

        /*
         * When used with a device instantiated as platform_device, bcm_suspend
         * can be called at any time as long as the platform device is bound,
         * so it should use bcm_device_lock to protect access to hci_uart
         * and device_wake-up GPIO.
         */
        mutex_lock(&bcm_device_lock);

        if (!bdev->hu)
                goto unlock;

        if (pm_runtime_active(dev))
                bcm_suspend_device(dev);

        if (device_may_wakeup(dev)) {
                error = enable_irq_wake(bdev->irq);
                if (!error)
                        bt_dev_dbg(bdev, "BCM irq: enabled");
        }

unlock:
        mutex_unlock(&bcm_device_lock);

        return 0;
}

/* resume callback */
static int bcm_resume(struct device *dev)
{
        struct bcm_device *bdev = dev_get_drvdata(dev);

        bt_dev_dbg(bdev, "resume: is_suspended %d", bdev->is_suspended);

        /*
         * When used with a device instantiated as platform_device, bcm_resume
         * can be called at any time as long as platform device is bound,
         * so it should use bcm_device_lock to protect access to hci_uart
         * and device_wake-up GPIO.
         */
        mutex_lock(&bcm_device_lock);

        if (!bdev->hu)
                goto unlock;

        if (device_may_wakeup(dev)) {
                disable_irq_wake(bdev->irq);
                bt_dev_dbg(bdev, "BCM irq: disabled");
        }

        bcm_resume_device(dev);

unlock:
        mutex_unlock(&bcm_device_lock);

        pm_runtime_disable(dev);
        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);

        return 0;
}
#endif

static const struct acpi_gpio_params int_last_device_wakeup_gpios = { 0, 0, false };
static const struct acpi_gpio_params int_last_shutdown_gpios = { 1, 0, false };
static const struct acpi_gpio_params int_last_host_wakeup_gpios = { 2, 0, false };

static const struct acpi_gpio_mapping acpi_bcm_int_last_gpios[] = {
        { "device-wakeup-gpios", &int_last_device_wakeup_gpios, 1 },
        { "shutdown-gpios", &int_last_shutdown_gpios, 1 },
        { "host-wakeup-gpios", &int_last_host_wakeup_gpios, 1 },
        { },
};

static const struct acpi_gpio_params int_first_host_wakeup_gpios = { 0, 0, false };
static const struct acpi_gpio_params int_first_device_wakeup_gpios = { 1, 0, false };
static const struct acpi_gpio_params int_first_shutdown_gpios = { 2, 0, false };

static const struct acpi_gpio_mapping acpi_bcm_int_first_gpios[] = {
        { "device-wakeup-gpios", &int_first_device_wakeup_gpios, 1 },
        { "shutdown-gpios", &int_first_shutdown_gpios, 1 },
        { "host-wakeup-gpios", &int_first_host_wakeup_gpios, 1 },
        { },
};

#ifdef CONFIG_ACPI
/* IRQ polarity of some chipsets are not defined correctly in ACPI table. */
static const struct dmi_system_id bcm_active_low_irq_dmi_table[] = {
        {
                .ident = "Asus T100TA",
                .matches = {
                        DMI_EXACT_MATCH(DMI_SYS_VENDOR,
                                        "ASUSTeK COMPUTER INC."),
                        DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100TA"),
                },
        },
        {
                .ident = "Asus T100CHI",
                .matches = {
                        DMI_EXACT_MATCH(DMI_SYS_VENDOR,
                                        "ASUSTeK COMPUTER INC."),
                        DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100CHI"),
                },
        },
        {       /* Handle ThinkPad 8 tablets with BCM2E55 chipset ACPI ID */
                .ident = "Lenovo ThinkPad 8",
                .matches = {
                        DMI_EXACT_MATCH(DMI_SYS_VENDOR, "LENOVO"),
                        DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "ThinkPad 8"),
                },
        },
        {
                .ident = "MINIX Z83-4",
                .matches = {
                        DMI_EXACT_MATCH(DMI_SYS_VENDOR, "MINIX"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
                },
        },
        { }
};

static int bcm_resource(struct acpi_resource *ares, void *data)
{
        struct bcm_device *dev = data;
        struct acpi_resource_extended_irq *irq;
        struct acpi_resource_gpio *gpio;
        struct acpi_resource_uart_serialbus *sb;

        switch (ares->type) {
        case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
                irq = &ares->data.extended_irq;
                dev->irq_active_low = irq->polarity == ACPI_ACTIVE_LOW;
                break;

        case ACPI_RESOURCE_TYPE_GPIO:
                gpio = &ares->data.gpio;
                if (gpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT)
                        dev->irq_active_low = gpio->polarity == ACPI_ACTIVE_LOW;
                break;

        case ACPI_RESOURCE_TYPE_SERIAL_BUS:
                sb = &ares->data.uart_serial_bus;
                if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_UART) {
                        dev->init_speed = sb->default_baud_rate;
                        dev->oper_speed = 4000000;
                }
                break;

        default:
                break;
        }

        return 0;
}
#endif /* CONFIG_ACPI */

static int bcm_get_resources(struct bcm_device *dev)
{
        dev->name = dev_name(dev->dev);

        dev->clk = devm_clk_get(dev->dev, NULL);

        dev->device_wakeup = devm_gpiod_get_optional(dev->dev,
                                                     "device-wakeup",
                                                     GPIOD_OUT_LOW);
        if (IS_ERR(dev->device_wakeup))
                return PTR_ERR(dev->device_wakeup);

        dev->shutdown = devm_gpiod_get_optional(dev->dev, "shutdown",
                                                GPIOD_OUT_LOW);
        if (IS_ERR(dev->shutdown))
                return PTR_ERR(dev->shutdown);

        /* IRQ can be declared in ACPI table as Interrupt or GpioInt */
        if (dev->irq <= 0) {
                struct gpio_desc *gpio;

                gpio = devm_gpiod_get_optional(dev->dev, "host-wakeup",
                                               GPIOD_IN);
                if (IS_ERR(gpio))
                        return PTR_ERR(gpio);

                dev->irq = gpiod_to_irq(gpio);
        }

        dev_info(dev->dev, "BCM irq: %d\n", dev->irq);
        return 0;
}

#ifdef CONFIG_ACPI
static int bcm_acpi_probe(struct bcm_device *dev)
{
        LIST_HEAD(resources);
        const struct dmi_system_id *dmi_id;
        const struct acpi_gpio_mapping *gpio_mapping = acpi_bcm_int_last_gpios;
        const struct acpi_device_id *id;
        struct resource_entry *entry;
        int ret;

        /* Retrieve GPIO data */
        id = acpi_match_device(dev->dev->driver->acpi_match_table, dev->dev);
        if (id)
                gpio_mapping = (const struct acpi_gpio_mapping *) id->driver_data;

        ret = devm_acpi_dev_add_driver_gpios(dev->dev, gpio_mapping);
        if (ret)
                return ret;

        /* Retrieve UART ACPI info */
        ret = acpi_dev_get_resources(ACPI_COMPANION(dev->dev),
                                     &resources, bcm_resource, dev);
        if (ret < 0)
                return ret;

        resource_list_for_each_entry(entry, &resources) {
                if (resource_type(entry->res) == IORESOURCE_IRQ) {
                        dev->irq = entry->res->start;
                        break;
                }
        }
        acpi_dev_free_resource_list(&resources);

        dmi_id = dmi_first_match(bcm_active_low_irq_dmi_table);
        if (dmi_id) {
                dev_warn(dev->dev, "%s: Overwriting IRQ polarity to active low",
                            dmi_id->ident);
                dev->irq_active_low = true;
        }

        return 0;
}
#else
static int bcm_acpi_probe(struct bcm_device *dev)
{
        return -EINVAL;
}
#endif /* CONFIG_ACPI */

static int bcm_of_probe(struct bcm_device *bdev)
{
        device_property_read_u32(bdev->dev, "max-speed", &bdev->oper_speed);
        return 0;
}

static int bcm_probe(struct platform_device *pdev)
{
        struct bcm_device *dev;
        int ret;

        dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
        if (!dev)
                return -ENOMEM;

        dev->dev = &pdev->dev;
        dev->irq = platform_get_irq(pdev, 0);

        if (has_acpi_companion(&pdev->dev)) {
                ret = bcm_acpi_probe(dev);
                if (ret)
                        return ret;
        }

        ret = bcm_get_resources(dev);
        if (ret)
                return ret;

        platform_set_drvdata(pdev, dev);

        dev_info(&pdev->dev, "%s device registered.\n", dev->name);

        /* Place this instance on the device list */
        mutex_lock(&bcm_device_lock);
        list_add_tail(&dev->list, &bcm_device_list);
        mutex_unlock(&bcm_device_lock);

        bcm_gpio_set_power(dev, false);

        return 0;
}

static int bcm_remove(struct platform_device *pdev)
{
        struct bcm_device *dev = platform_get_drvdata(pdev);

        mutex_lock(&bcm_device_lock);
        list_del(&dev->list);
        mutex_unlock(&bcm_device_lock);

        dev_info(&pdev->dev, "%s device unregistered.\n", dev->name);

        return 0;
}

static const struct hci_uart_proto bcm_proto = {
        .id             = HCI_UART_BCM,
        .name           = "Broadcom",
        .manufacturer   = 15,
        .init_speed     = 115200,
        .open           = bcm_open,
        .close          = bcm_close,
        .flush          = bcm_flush,
        .setup          = bcm_setup,
        .set_baudrate   = bcm_set_baudrate,
        .recv           = bcm_recv,
        .enqueue        = bcm_enqueue,
        .dequeue        = bcm_dequeue,
};

#ifdef CONFIG_ACPI
static const struct acpi_device_id bcm_acpi_match[] = {
        { "BCM2E1A", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E39", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E3A", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E3D", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E3F", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E40", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E54", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E55", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E64", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E65", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E67", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E71", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E7B", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E7C", (kernel_ulong_t)&acpi_bcm_int_last_gpios },
        { "BCM2E95", (kernel_ulong_t)&acpi_bcm_int_first_gpios },
        { "BCM2E96", (kernel_ulong_t)&acpi_bcm_int_first_gpios },
        { "BCM2EA4", (kernel_ulong_t)&acpi_bcm_int_first_gpios },
        { },
};
MODULE_DEVICE_TABLE(acpi, bcm_acpi_match);
#endif

/* suspend and resume callbacks */
static const struct dev_pm_ops bcm_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(bcm_suspend, bcm_resume)
        SET_RUNTIME_PM_OPS(bcm_suspend_device, bcm_resume_device, NULL)
};

static struct platform_driver bcm_driver = {
        .probe = bcm_probe,
        .remove = bcm_remove,
        .driver = {
                .name = "hci_bcm",
                .acpi_match_table = ACPI_PTR(bcm_acpi_match),
                .pm = &bcm_pm_ops,
        },
};

static int bcm_serdev_probe(struct serdev_device *serdev)
{
        struct bcm_device *bcmdev;
        int err;

        bcmdev = devm_kzalloc(&serdev->dev, sizeof(*bcmdev), GFP_KERNEL);
        if (!bcmdev)
                return -ENOMEM;

        bcmdev->dev = &serdev->dev;
        bcmdev->hu = &bcmdev->serdev_hu;
        bcmdev->serdev_hu.serdev = serdev;
        serdev_device_set_drvdata(serdev, bcmdev);

        if (has_acpi_companion(&serdev->dev))
                err = bcm_acpi_probe(bcmdev);
        else
                err = bcm_of_probe(bcmdev);
        if (err)
                return err;

        err = bcm_get_resources(bcmdev);
        if (err)
                return err;

        bcm_gpio_set_power(bcmdev, false);

        return hci_uart_register_device(&bcmdev->serdev_hu, &bcm_proto);
}

static void bcm_serdev_remove(struct serdev_device *serdev)
{
        struct bcm_device *bcmdev = serdev_device_get_drvdata(serdev);

        hci_uart_unregister_device(&bcmdev->serdev_hu);
}

#ifdef CONFIG_OF
static const struct of_device_id bcm_bluetooth_of_match[] = {
        { .compatible = "brcm,bcm43438-bt" },
        { },
};
MODULE_DEVICE_TABLE(of, bcm_bluetooth_of_match);
#endif

static struct serdev_device_driver bcm_serdev_driver = {
        .probe = bcm_serdev_probe,
        .remove = bcm_serdev_remove,
        .driver = {
                .name = "hci_uart_bcm",
                .of_match_table = of_match_ptr(bcm_bluetooth_of_match),
                .acpi_match_table = ACPI_PTR(bcm_acpi_match),
                .pm = &bcm_pm_ops,
        },
};

int __init bcm_init(void)
{
        /* For now, we need to keep both platform device
         * driver (ACPI generated) and serdev driver (DT).
         */
        platform_driver_register(&bcm_driver);
        serdev_device_driver_register(&bcm_serdev_driver);

        return hci_uart_register_proto(&bcm_proto);
}

int __exit bcm_deinit(void)
{
        platform_driver_unregister(&bcm_driver);
        serdev_device_driver_unregister(&bcm_serdev_driver);

        return hci_uart_unregister_proto(&bcm_proto);
}