From 41c372dcad935fe7c27ec45211bad810515110bd Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 3 Sep 2009 17:22:03 -0700 Subject: 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: Dmitry Torokhov --- drivers/input/touchscreen/wacom_w8001.c | 121 +++++++++++--------------------- 1 file changed, 40 insertions(+), 81 deletions(-) (limited to 'drivers/input/touchscreen') diff --git a/drivers/input/touchscreen/wacom_w8001.c b/drivers/input/touchscreen/wacom_w8001.c index 2f33a0167644..56dc35c94bb1 100644 --- a/drivers/input/touchscreen/wacom_w8001.c +++ b/drivers/input/touchscreen/wacom_w8001.c @@ -25,18 +25,16 @@ MODULE_AUTHOR("Jaya Kumar "); 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 -#define W8001_TAB_BYTE 0x40 +#define W8001_LEAD_MASK 0x80 +#define W8001_LEAD_BYTE 0x80 +#define W8001_TAB_MASK 0x40 +#define W8001_TAB_BYTE 0x40 -#define W8001_QUERY_PACKET 0x20 +#define W8001_QUERY_PACKET 0x20 + +#define W8001_CMD_START '1' +#define W8001_CMD_QUERY '*' struct w8001_coord { u8 rdy; @@ -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; + int rc; - mutex_lock(&w8001->cmd_mutex); - - 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; - } - wait_for_completion_timeout(&w8001->cmd_done, HZ); + rc = serio_write(w8001->serio, command); + if (rc == 0 && wait_response) { - 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; + wait_for_completion_timeout(&w8001->cmd_done, HZ); + 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); -- cgit v1.2.3-59-g8ed1b