[PATCH] Input: mouse: synaptics - change msleep to usleep_range for small msecs

From: Aniroop Mathur
Date: Mon Nov 28 2016 - 14:46:07 EST


msleep(1~20) may not do what the caller intends, and will often sleep longer.
(~20 ms actual sleep for any value given in the 1~20ms range)
This is not the desired behaviour for many cases like device resume time,
device suspend time, device enable time, retry logic, etc.
Thus, change msleep to usleep_range for precise wakeups.

Signed-off-by: Aniroop Mathur <a.mathur@xxxxxxxxxxx>
---
drivers/input/mouse/synaptics_i2c.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/input/mouse/synaptics_i2c.c b/drivers/input/mouse/synaptics_i2c.c
index aa7c5da..4d688a6 100644
--- a/drivers/input/mouse/synaptics_i2c.c
+++ b/drivers/input/mouse/synaptics_i2c.c
@@ -29,7 +29,7 @@
* after soft reset, we should wait for 1 ms
* before the device becomes operational
*/
-#define SOFT_RESET_DELAY_MS 3
+#define SOFT_RESET_DELAY_US 3000
/* and after hard reset, we should wait for max 500ms */
#define HARD_RESET_DELAY_MS 500

@@ -311,7 +311,7 @@ static int synaptics_i2c_reset_config(struct i2c_client *client)
if (ret) {
dev_err(&client->dev, "Unable to reset device\n");
} else {
- msleep(SOFT_RESET_DELAY_MS);
+ usleep_range(SOFT_RESET_DELAY_US, SOFT_RESET_DELAY_US + 100);
ret = synaptics_i2c_config(client);
if (ret)
dev_err(&client->dev, "Unable to config device\n");
--
2.6.2