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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2009-09-03 17:22:03 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2009-09-03 20:38:37 -0700
commit41c372dcad935fe7c27ec45211bad810515110bd (patch)
treee6637c5de1f07c7ca23132efea4c55ca838a4fa0
parent1ba36e11b227e32f818aea5b4d84f5cbff71e7db (diff)
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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 <dtor@mail.ru>
-rw-r--r--drivers/input/touchscreen/wacom_w8001.c121
1 files changed, 40 insertions, 81 deletions
diff --git a/drivers/input/touchscreen/wacom_w8001.c b/drivers/input/touchscreen/wacom_w8001.c
index 2f33a016764..56dc35c94bb 100644
--- a/drivers/input/touchscreen/wacom_w8001.c
+++ b/drivers/input/touchscreen/wacom_w8001.c
@@ -25,18 +25,16 @@ 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
-#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);