path: root/drivers/bluetooth/hci_intel.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 *  Bluetooth HCI UART driver for Intel devices
 *
 *  Copyright (C) 2015  Intel Corporation
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/firmware.h>
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/tty.h>
#include <linux/platform_device.h>
#include <linux/gpio/consumer.h>
#include <linux/acpi.h>
#include <linux/interrupt.h>
#include <linux/pm_runtime.h>

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

#include "hci_uart.h"
#include "btintel.h"

#define STATE_BOOTLOADER	0
#define STATE_DOWNLOADING	1
#define STATE_FIRMWARE_LOADED	2
#define STATE_FIRMWARE_FAILED	3
#define STATE_BOOTING		4
#define STATE_LPM_ENABLED	5
#define STATE_TX_ACTIVE		6
#define STATE_SUSPENDED		7
#define STATE_LPM_TRANSACTION	8

#define HCI_LPM_WAKE_PKT 0xf0
#define HCI_LPM_PKT 0xf1
#define HCI_LPM_MAX_SIZE 10
#define HCI_LPM_HDR_SIZE HCI_EVENT_HDR_SIZE

#define LPM_OP_TX_NOTIFY 0x00
#define LPM_OP_SUSPEND_ACK 0x02
#define LPM_OP_RESUME_ACK 0x03

#define LPM_SUSPEND_DELAY_MS 1000

struct hci_lpm_pkt {
	__u8 opcode;
	__u8 dlen;
	__u8 data[];
} __packed;

struct intel_device {
	struct list_head list;
	struct platform_device *pdev;
	struct gpio_desc *reset;
	struct hci_uart *hu;
	struct mutex hu_lock;
	int irq;
};

static LIST_HEAD(intel_device_list);
static DEFINE_MUTEX(intel_device_list_lock);

struct intel_data {
	struct sk_buff *rx_skb;
	struct sk_buff_head txq;
	struct work_struct busy_work;
	struct hci_uart *hu;
	unsigned long flags;
};

static u8 intel_convert_speed(unsigned int speed)
{
	switch (speed) {
	case 9600:
		return 0x00;
	case 19200:
		return 0x01;
	case 38400:
		return 0x02;
	case 57600:
		return 0x03;
	case 115200:
		return 0x04;
	case 230400:
		return 0x05;
	case 460800:
		return 0x06;
	case 921600:
		return 0x07;
	case 1843200:
		return 0x08;
	case 3250000:
		return 0x09;
	case 2000000:
		return 0x0a;
	case 3000000:
		return 0x0b;
	default:
		return 0xff;
	}
}

static int intel_wait_booting(struct hci_uart *hu)
{
	struct intel_data *intel = hu->priv;
	int err;

	err = wait_on_bit_timeout(&intel->flags, STATE_BOOTING,
				  TASK_INTERRUPTIBLE,
				  msecs_to_jiffies(1000));

	if (err == -EINTR) {
		bt_dev_err(hu->hdev, "Device boot interrupted");
		return -EINTR;
	}

	if (err) {
		bt_dev_err(hu->hdev, "Device boot timeout");
		return -ETIMEDOUT;
	}

	return err;
}

#ifdef CONFIG_PM
static int intel_wait_lpm_transaction(struct hci_uart *hu)
{
	struct intel_data *intel = hu->priv;
	int err;

	err = wait_on_bit_timeout(&intel->flags, STATE_LPM_TRANSACTION,
				  TASK_INTERRUPTIBLE,
				  msecs_to_jiffies(1000));

	if (err == -EINTR) {
		bt_dev_err(hu->hdev, "LPM transaction interrupted");
		return -EINTR;
	}

	if (err) {
		bt_dev_err(hu->hdev, "LPM transaction timeout");
		return -ETIMEDOUT;
	}

	return err;
}

static int intel_lpm_suspend(struct hci_uart *hu)
{
	static const u8 suspend[] = { 0x01, 0x01, 0x01 };
	struct intel_data *intel = hu->priv;
	struct sk_buff *skb;

	if (!test_bit(STATE_LPM_ENABLED, &intel->flags) ||
	    test_bit(STATE_SUSPENDED, &intel->flags))
		return 0;

	if (test_bit(STATE_TX_ACTIVE, &intel->flags))
		return -EAGAIN;