path: root/drivers/input/mouse/cyapa.c

/*
 * Cypress APA trackpad with I2C interface
 *
 * Author: Dudley Du <dudl@cypress.com>
 * Further cleanup and restructuring by:
 *   Daniel Kurtz <djkurtz@chromium.org>
 *   Benson Leung <bleung@chromium.org>
 *
 * Copyright (C) 2011-2015 Cypress Semiconductor, Inc.
 * Copyright (C) 2011-2012 Google, Inc.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive for
 * more details.
 */

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/pm_runtime.h>
#include <linux/acpi.h>
#include <linux/of.h>
#include "cyapa.h"


#define CYAPA_ADAPTER_FUNC_NONE   0
#define CYAPA_ADAPTER_FUNC_I2C    1
#define CYAPA_ADAPTER_FUNC_SMBUS  2
#define CYAPA_ADAPTER_FUNC_BOTH   3

#define CYAPA_FW_NAME		"cyapa.bin"

const char product_id[] = "CYTRA";

static int cyapa_reinitialize(struct cyapa *cyapa);

bool cyapa_is_pip_bl_mode(struct cyapa *cyapa)
{
	if (cyapa->gen == CYAPA_GEN6 && cyapa->state == CYAPA_STATE_GEN6_BL)
		return true;

	if (cyapa->gen == CYAPA_GEN5 && cyapa->state == CYAPA_STATE_GEN5_BL)
		return true;

	return false;
}

bool cyapa_is_pip_app_mode(struct cyapa *cyapa)
{
	if (cyapa->gen == CYAPA_GEN6 && cyapa->state == CYAPA_STATE_GEN6_APP)
		return true;

	if (cyapa->gen == CYAPA_GEN5 && cyapa->state == CYAPA_STATE_GEN5_APP)
		return true;

	return false;
}

static bool cyapa_is_bootloader_mode(struct cyapa *cyapa)
{
	if (cyapa_is_pip_bl_mode(cyapa))
		return true;

	if (cyapa->gen == CYAPA_GEN3 &&
		cyapa->state >= CYAPA_STATE_BL_BUSY &&
		cyapa->state <= CYAPA_STATE_BL_ACTIVE)
		return true;

	return false;
}

static inline bool cyapa_is_operational_mode(struct cyapa *cyapa)
{
	if (cyapa_is_pip_app_mode(cyapa))
		return true;

	if (cyapa->gen == CYAPA_GEN3 && cyapa->state == CYAPA_STATE_OP)
		return true;

	return false;
}

/* Returns 0 on success, else negative errno on failure. */
static ssize_t cyapa_i2c_read(struct cyapa *cyapa, u8 reg, size_t len,
					u8 *values)
{
	struct i2c_client *client = cyapa->client;
	struct i2c_msg msgs[] = {
		{
			.addr = client->addr,
			.flags = 0,
			.len = 1,
			.buf = &reg,
		},
		{
			.addr = client->addr,
			.flags = I2C_M_RD,
			.len = len,
			.buf = values,
		},
	};
	int ret;

	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));

	if (ret != ARRAY_SIZE(msgs))
		return ret < 0 ? ret : -EIO;

	return 0;
}

/**
 * cyapa_i2c_write - Execute i2c block data write operation
 * @cyapa: Handle to this driver
 * @reg: Offset of the data to written in the register map
 * @len: number of bytes to write
 * @values: Data to be written
 *
 * Return negative errno code on error; return zero when success.
 */
static int cyapa_i2c_write(struct cyapa *cyapa, u8 reg,
					 size_t len, const void *values)
{
	struct i2c_client *client = cyapa->client;
	char buf[32];
	int ret;

	if (len > sizeof(buf) - 1)
		return -ENOMEM;

	buf[0] = reg;
	memcpy(&buf[1], values, len);

	ret = i2c_master_send(client, buf, len + 1);
	if (ret != len + 1)
		return ret < 0 ? ret : -EIO;

	return 0;
}

static u8 cyapa_check_adapter_functionality(struct i2c_client *client)
{
	u8 ret = CYAPA_ADAPTER_FUNC_NONE;

	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
		ret |= CYAPA_ADAPTER_FUNC_I2C;
	if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
				     I2C_FUNC_SMBUS_BLOCK_DATA |
				     I2C_FUNC_SMBUS_I2C_BLOCK))
		ret |= CYAPA_ADAPTER_FUNC_SMBUS;
	return ret;
}

/*
 * Query device for its current operating state.
 */
static int cyapa_get_state(struct cyapa *cyapa)
{
	u8 status[BL_STATUS_SIZE];
	u8 cmd[32];
	/* The i2c address of gen4 and gen5 trackpad device must be even. */
	bool even_addr = ((cyapa->client->addr & 0x0001) == 0);
	bool smbus = false;
	int retries = 2;
	int error;

	cyapa->state = CYAPA_STATE_NO_DEVICE;

	/*
	 * Get trackpad status by reading 3 registers starting from 0.
	 * If the device is in the bootloader, this will be BL_HEAD.
	 * If the device is in operation mode, this will be the DATA regs.
	 *
	 */
	error = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET, BL_STATUS_SIZE,
				       status);

	/*
	 * On smbus systems in OP mode, the i2c_reg_read will fail with
	 * -ETIMEDOUT.  In this case, try again using the smbus equivalent
	 * command.  This should return a BL_HEAD indicating CYAPA_STATE_OP.
	 */
	if (cyapa->smbus && (error == -ETIMEDOUT || error == -ENXIO)) {
		if (!even_addr)
			error = cyapa_read_block(cyapa,
					CYAPA_CMD_BL_STATUS, status);
		smbus = true;
	}

	if (error != BL_STATUS_SIZE)
		goto error;

	/*
	 * Detect trackpad protocol based on characteristic registers and bits.
	 */
	do {
		cyapa->status[REG_OP_STATUS] = status[REG_OP_STATUS];
		cyapa->status[REG_BL_STATUS] = status[REG_BL_STATUS];
		cyapa->status[REG_BL_ERROR] = status[REG_BL_ERROR];

		if (cyapa->gen == CYAPA_GEN_UNKNOWN ||
				cyapa->gen == CYAPA_GEN3) {
			error = cyapa_gen3_ops.state_parse(cyapa,
					status, BL_STATUS_SIZE);
			if (!error)
				goto out_detected;
		}
		if (cyapa->gen == CYAPA_GEN_UNKNOWN ||
				cyapa->gen == CYAPA_GEN6 ||
				cyapa->gen == CYAPA_GEN5) {
			error = cyapa_pip_state_parse(cyapa,
					status, BL_STATUS_SIZE);
			if (!error)
				goto out_detected;
		}
		/* For old Gen5 trackpads detecting. */
		if ((cyapa->gen == CYAPA_GEN_UNKNOWN ||
				cyapa->gen == CYAPA_GEN5) &&
			!smbus && even_addr) {
			error = cyapa_gen5_ops.state_parse(cyapa,
					status, BL_STATUS_SIZE);
			if (!error)
				goto out_detected;
		}

		/*
		 * Write 0x00 0x00 to trackpad device to force update its
		 * status, then redo the detection again.
		 */
		if (!smbus) {
			cmd[0] = 0x00;
			cmd[1] = 0x00;
			error = cyapa_i2c_write(cyapa, 0, 2, cmd);
			if (error)
				goto error;

			msleep(50);

			error = cyapa_i2c_read(cyapa, BL_HEAD_OFFSET,
					BL_STATUS_SIZE, status);
			if (error)
				goto error;
		}
	} while (--retries > 0 && !smbus);

	goto error;

out_detected:
	if (cyapa->state <= CYAPA_STATE_BL_BUSY)
		return -EAGAIN;
	return 0;

error:
	return (error < 0) ? error : -EAGAIN;
}

/*
 * Poll device for its status in a loop, waiting up to timeout for a response.
 *
 * When the device switches state, it usually takes ~300 ms.
 * However, when running a new firmware image, the device must calibrate its
 * sensors, which can take as long as 2 seconds.
 *
 * Note: The timeout has granularity of the polling rate, which is 100 ms.
 *
 * Returns:
 *   0 when the device eventually responds with a valid non-busy state.
 *   -ETIMEDOUT if device never responds (too many -EAGAIN)
 *   -EAGAIN    if bootload is busy, or unknown state.
 *   < 0        other errors
 */
int cyapa_poll_state(struct cyapa *cyapa, unsigned int timeout)
{
	int error;
	int tries = timeout / 100;

	do {
		error = cyapa_get_state(cyapa);
		if (!error && cyapa->state > CYAPA_STATE_BL_BUSY)
			return 0;

		msleep(100);
	} while (tries--);

	return (error == -EAGAIN || error == -ETIMEDOUT) ? -ETIMEDOUT : error;
}

/*
 * Check if device is operational.
 *
 * An operational device is responding, has exited bootloader, and has
 * firmware supported by this driver.
 *
 * Returns:
 *   -ENODEV no device
 *   -EBUSY  no device or in bootloader
 *   -EIO    failure while reading from device
 *   -ETIMEDOUT timeout failure for bus idle or bus no response
 *   -EAGAIN device is still in bootloader
 *           if ->state = CYAPA_STATE_BL_IDLE, device has invalid firmware
 *   -EINVAL device is in operational mode, but not supported by this driver
 *   0       device is supported
 */
static int cyapa_check_is_operational(struct cyapa *cyapa)
{
	int error;

	error = cyapa_poll_state(cyapa, 4000);
	if (error)
		return error;

	switch (cyapa->gen) {
	case CYAPA_GEN6:
		cyapa->ops = &cyapa_gen6_ops;
		break;
	case CYAPA_GEN5:
		cyapa-