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Commit 41c372dc authored by Dmitry Torokhov's avatar Dmitry Torokhov
Browse files

Input: wacom_w8001 - simplify querying logic 



There is no need for locking when we send query and start commands
to the touchscreen since there is no concurrency.

Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
parent 1ba36e11

drivers/input/touchscreen/wacom_w8001.c

+40 −81
Original line number Diff line number Diff line
@@ -25,12 +25,7 @@ MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>"); 
MODULE_DESCRIPTION(DRIVER_DESC);

MODULE_LICENSE("GPL");



/*

 * Definitions & global arrays.

 */



#define W8001_MAX_LENGTH	11

#define W8001_PACKET_LEN	11

#define W8001_LEAD_MASK		0x80

#define W8001_LEAD_BYTE		0x80

#define W8001_TAB_MASK		0x40
@@ -38,6 +33,9 @@ MODULE_LICENSE("GPL"); 


#define W8001_QUERY_PACKET	0x20



#define W8001_CMD_START		'1'

#define W8001_CMD_QUERY		'*'



struct w8001_coord {

	u8 rdy;

	u8 tsw;
@@ -57,18 +55,19 @@ struct w8001_coord { 
struct w8001 {

	struct input_dev *dev;

	struct serio *serio;

	struct mutex cmd_mutex;

	struct completion cmd_done;

	int id;

	int idx;

	unsigned char expected_packet;

	unsigned char response_type;

	unsigned char response[W8001_MAX_LENGTH];

	unsigned char data[W8001_MAX_LENGTH];

	unsigned char response[W8001_PACKET_LEN];

	char phys[32];

};



static int parse_data(u8 *data, struct w8001_coord *coord)

static void parse_data(u8 *data, struct w8001_coord *coord)

{

	memset(coord, 0, sizeof(*coord));



	coord->rdy = data[0] & 0x20;

	coord->tsw = data[0] & 0x01;

	coord->f1 = data[0] & 0x02;
@@ -87,15 +86,15 @@ static int parse_data(u8 *data, struct w8001_coord *coord) 


	coord->tilt_x = data[7] & 0x7F;

	coord->tilt_y = data[8] & 0x7F;



	return 0;

}



static void w8001_process_data(struct w8001 *w8001, unsigned char data)

static irqreturn_t w8001_interrupt(struct serio *serio,

				   unsigned char data, unsigned int flags)

{

	struct w8001 *w8001 = serio_get_drvdata(serio);

	struct input_dev *dev = w8001->dev;

	u8 tmp;

	struct w8001_coord coord;

	unsigned char tmp;



	w8001->data[w8001->idx] = data;

	switch (w8001->idx++) {
@@ -105,12 +104,13 @@ static void w8001_process_data(struct w8001 *w8001, unsigned char data) 
			w8001->idx = 0;

		}

		break;



	case 8:

		tmp = w8001->data[0] & W8001_TAB_MASK;

		if (unlikely(tmp == W8001_TAB_BYTE))

			break;



		w8001->idx = 0;

		memset(&coord, 0, sizeof(coord));

		parse_data(w8001->data, &coord);

		input_report_abs(dev, ABS_X, coord.x);

		input_report_abs(dev, ABS_Y, coord.y);
@@ -118,86 +118,48 @@ static void w8001_process_data(struct w8001 *w8001, unsigned char data) 
		input_report_key(dev, BTN_TOUCH, coord.tsw);

		input_sync(dev);

		break;



	case 10:

		w8001->idx = 0;

		memcpy(w8001->response, &w8001->data, W8001_PACKET_LEN);

		w8001->expected_packet = W8001_QUERY_PACKET;

		memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);

		w8001->response_type = W8001_QUERY_PACKET;

		complete(&w8001->cmd_done);

		break;

	}

}





static irqreturn_t w8001_interrupt(struct serio *serio,

		unsigned char data, unsigned int flags)

{

	struct w8001 *w8001 = serio_get_drvdata(serio);



	w8001_process_data(w8001, data);



	return IRQ_HANDLED;

}



static int w8001_async_command(struct w8001 *w8001, unsigned char *packet,

					int len)

{

	int rc = -1;

	int i;



	mutex_lock(&w8001->cmd_mutex);



	for (i = 0; i < len; i++) {

		if (serio_write(w8001->serio, packet[i]))

			goto out;

	}

	rc = 0;



out:

	mutex_unlock(&w8001->cmd_mutex);

	return rc;

}



static int w8001_command(struct w8001 *w8001, unsigned char *packet, int len)

static int w8001_command(struct w8001 *w8001, unsigned char command,

			 bool wait_response)

{

	int rc = -1;

	int i;



	mutex_lock(&w8001->cmd_mutex);

	int rc;



	serio_pause_rx(w8001->serio);

	w8001->response_type = 0;

	init_completion(&w8001->cmd_done);

	serio_continue_rx(w8001->serio);



	for (i = 0; i < len; i++) {

		if (serio_write(w8001->serio, packet[i]))

			goto out;

	}

	rc = serio_write(w8001->serio, command);

	if (rc == 0 && wait_response) {



		wait_for_completion_timeout(&w8001->cmd_done, HZ);



	if (w8001->expected_packet == W8001_QUERY_PACKET) {

		/* We are back in reporting mode, the query was ACKed */

		memcpy(packet, w8001->response, W8001_PACKET_LEN);

		rc = 0;

		if (w8001->response_type != W8001_QUERY_PACKET)

			rc = -EIO;

	}



out:

	mutex_unlock(&w8001->cmd_mutex);

	return rc;

}



static int w8001_setup(struct w8001 *w8001)

{

	struct w8001_coord coord;

	struct input_dev *dev = w8001->dev;

	unsigned char start[1] = { '1' };

	unsigned char query[11] = { '*' };

	struct w8001_coord coord;

	int error;



	if (w8001_command(w8001, query, 1))

		return -1;

	error = w8001_command(w8001, W8001_CMD_QUERY, true);

	if (error)

		return error;



	memset(&coord, 0, sizeof(coord));

	parse_data(query, &coord);

	parse_data(w8001->response, &coord);



	input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);

	input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
@@ -205,10 +167,7 @@ static int w8001_setup(struct w8001 *w8001) 
	input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);

	input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);



	if (w8001_async_command(w8001, start, 1))

		return -1;



	return 0;

	return w8001_command(w8001, W8001_CMD_START, false);

}



/*
@@ -249,7 +208,6 @@ static int w8001_connect(struct serio *serio, struct serio_driver *drv) 
	w8001->serio = serio;

	w8001->id = serio->id.id;

	w8001->dev = input_dev;

	mutex_init(&w8001->cmd_mutex);

	init_completion(&w8001->cmd_done);

	snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
@@ -269,7 +227,8 @@ static int w8001_connect(struct serio *serio, struct serio_driver *drv) 
	if (err)

		goto fail2;



	if (w8001_setup(w8001))

	err = w8001_setup(w8001);

	if (err)

		goto fail3;



	err = input_register_device(w8001->dev);