path: root/drivers/bluetooth/hci_qca.c

/*
 *  Bluetooth Software UART Qualcomm protocol
 *
 *  HCI_IBS (HCI In-Band Sleep) is Qualcomm's power management
 *  protocol extension to H4.
 *
 *  Copyright (C) 2007 Texas Instruments, Inc.
 *  Copyright (c) 2010, 2012, 2018 The Linux Foundation. All rights reserved.
 *
 *  Acknowledgements:
 *  This file is based on hci_ll.c, which was...
 *  Written by Ohad Ben-Cohen <ohad@bencohen.org>
 *  which was in turn based on hci_h4.c, which was written
 *  by Maxim Krasnyansky and Marcel Holtmann.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation
 *
 *  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/clk.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/serdev.h>
#include <asm/unaligned.h>

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

#include "hci_uart.h"
#include "btqca.h"

/* HCI_IBS protocol messages */
#define HCI_IBS_SLEEP_IND	0xFE
#define HCI_IBS_WAKE_IND	0xFD
#define HCI_IBS_WAKE_ACK	0xFC
#define HCI_MAX_IBS_SIZE	10

#define IBS_WAKE_RETRANS_TIMEOUT_MS	100
#define IBS_TX_IDLE_TIMEOUT_MS		2000
#define CMD_TRANS_TIMEOUT_MS		100

/* susclk rate */
#define SUSCLK_RATE_32KHZ	32768

/* Controller debug log header */
#define QCA_DEBUG_HANDLE	0x2EDC

enum qca_flags {
	QCA_IBS_ENABLED,
};

/* HCI_IBS transmit side sleep protocol states */
enum tx_ibs_states {
	HCI_IBS_TX_ASLEEP,
	HCI_IBS_TX_WAKING,
	HCI_IBS_TX_AWAKE,
};

/* HCI_IBS receive side sleep protocol states */
enum rx_states {
	HCI_IBS_RX_ASLEEP,
	HCI_IBS_RX_AWAKE,
};

/* HCI_IBS transmit and receive side clock state vote */
enum hci_ibs_clock_state_vote {
	HCI_IBS_VOTE_STATS_UPDATE,
	HCI_IBS_TX_VOTE_CLOCK_ON,
	HCI_IBS_TX_VOTE_CLOCK_OFF,
	HCI_IBS_RX_VOTE_CLOCK_ON,
	HCI_IBS_RX_VOTE_CLOCK_OFF,
};

struct qca_data {
	struct hci_uart *hu;
	struct sk_buff *rx_skb;
	struct sk_buff_head txq;
	struct sk_buff_head tx_wait_q;	/* HCI_IBS wait queue	*/
	spinlock_t hci_ibs_lock;	/* HCI_IBS state lock	*/
	u8 tx_ibs_state;	/* HCI_IBS transmit side power state*/
	u8 rx_ibs_state;	/* HCI_IBS receive side power state */
	bool tx_vote;		/* Clock must be on for TX */
	bool rx_vote;		/* Clock must be on for RX */
	struct timer_list tx_idle_timer;
	u32 tx_idle_delay;
	struct timer_list wake_retrans_timer;
	u32 wake_retrans;
	struct workqueue_struct *workqueue;
	struct work_struct ws_awake_rx;
	struct work_struct ws_awake_device;
	struct work_struct ws_rx_vote_off;
	struct work_struct ws_tx_vote_off;
	unsigned long flags;

	/* For debugging purpose */
	u64 ibs_sent_wacks;
	u64 ibs_sent_slps;
	u64 ibs_sent_wakes;
	u64 ibs_recv_wacks;
	u64 ibs_recv_slps;
	u64 ibs_recv_wakes;
	u64 vote_last_jif;
	u32 vote_on_ms;
	u32 vote_off_ms;
	u64 tx_votes_on;
	u64 rx_votes_on;
	u64 tx_votes_off;
	u64 rx_votes_off;
	u64 votes_on;
	u64 votes_off;
};

enum qca_speed_type {
	QCA_INIT_SPEED = 1,
	QCA_OPER_SPEED
};

/*
 * Voltage regulator information required for configuring the
 * QCA Bluetooth chipset
 */
struct qca_vreg {
	const char *name;
	unsigned int min_uV;
	unsigned int max_uV;
	unsigned int load_uA;
};

struct qca_vreg_data {
	enum qca_btsoc_type soc_type;
	struct qca_vreg *vregs;
	size_t num_vregs;
};

/*
 * Platform data for the QCA Bluetooth power driver.
 */
struct qca_power {
	struct device *dev;
	const struct qca_vreg_data *vreg_data;
	struct regulator_bulk_data *vreg_bulk;
	bool vregs_on;
};

struct qca_serdev {
	struct hci_uart	 serdev_hu;
	struct gpio_desc *bt_en;
	struct clk	 *susclk;
	enum qca_btsoc_type btsoc_type;
	struct qca_power *bt_power;
	u32 init_speed;
	u32 oper_speed;
};

static int qca_power_setup(struct hci_uart *hu, bool on);
static void qca_power_shutdown(struct hci_uart *hu);
static int qca_power_off(struct hci_dev *hdev);

static enum qca_btsoc_type qca_soc_type(struct hci_uart *hu)
{
	enum qca_btsoc_type soc_type;

	if (hu->serdev) {
		struct qca_serdev *qsd = serdev_device_get_drvdata(hu->serdev);

		soc_type = qsd->btsoc_type;
	} else {
		soc_type = QCA_ROME;
	}

	return soc_type;
}

static void __serial_clock_on(struct tty_struct *tty)
{
	/* TODO: Some chipset requires to enable UART clock on client
	 * side to save power consumption or manual work is required.
	 * Please put your code to control UART clock here if needed
	 */
}

static void __serial_clock_off(struct tty_struct *tty)
{
	/* TODO: Some chipset requires to disable UART clock on client
	 * side to save power consumption or manual work is required.
	 * Please put your code to control UART clock off here if needed
	 */
}

/* serial_clock_vote needs to be called with the ibs lock held */
static void serial_clock_vote(unsigned long vote, struct hci_uart *hu)
{
	struct qca_data *qca = hu->priv;
	unsigned int diff;

	bool old_vote = (qca->tx_vote | qca->rx_vote);
	bool new_vote;

	switch (vote) {
	case HCI_IBS_VOTE_STATS_UPDATE:
		diff = jiffies_to_msecs(jiffies - qca->vote_last_jif);

		if (old_vote)
			qca->vote_off_ms += diff;
		else
			qca->vote_on_ms += diff;
		return;

	case HCI_IBS_TX_VOTE_CLOCK_ON:
		qca->tx_vote = true;
		qca->tx_votes_on++;
		new_vote = true;
		break;

	case HCI_IBS_RX_VOTE_CLOCK_ON:
		qca->rx_vote = true;
		qca->rx_votes_on++;
		new_vote = true;
		break;

	case HCI_IBS_TX_VOTE_CLOCK_OFF:
		qca->tx_vote = false;
		qca->tx_votes_off++;
		new_vote = qca->rx_vote | qca->tx_vote;
		break;

	case HCI_IBS_RX_VOTE_CLOCK_OFF:
		qca->rx_vote = false;
		qca->rx_votes_off++;
		new_vote = qca->rx_vote | qca->tx_vote;
		break;

	default:
		BT_ERR("Voting irregularity");
		return;
	}

	if (new_vote != old_vote) {
		if (new_vote)
			__serial_clock_on(hu->tty);
		else
			__serial_clock_off(hu->tty);

		BT_DBG("Vote serial clock %s(%s)", new_vote ? "true" : "false",
		       vote ? "true" : "false");

		diff = jiffies_to_msecs(jiffies - qca->vote_last_jif);

		if (new_vote) {
			qca->votes_on++;
			qca->vote_off_ms += diff;
		} else {
			qca->votes_off++;
			qca->vote_on_ms += diff;
		}
		qca->vote_last_jif = jiffies;
	}
}

/* Builds and sends an HCI_IBS command packet.
 * These are very simple packets with only 1 cmd byte.
 */
static int send_hci_ibs_cmd(u8 cmd, st