drivers/video/backlight/ltv350qv.c: use usleep_range() instead of msleep() for small sleeps

Since msleep() might not sleep for the desired amount when less than 20ms,
use usleep_range().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/backlight/ltv350qv.c

@@ -75,7 +75,7 @@ static int ltv350qv_power_on(struct ltv350qv *lcd)
 	/* Power On Reset Display off State */
 	if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, 0x0000))
 		goto err;
-	msleep(15);
+	usleep_range(15000, 16000);
 
 	/* Power Setting Function 1 */
 	if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE))
@@ -153,7 +153,7 @@ err_settings:
 err_power2:
 err_power1:
 	ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000);
-	msleep(1);
+	usleep_range(1000, 1100);
 err:
 	ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE);
 	return -EIO;
@@ -175,7 +175,7 @@ static int ltv350qv_power_off(struct ltv350qv *lcd)
 	ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000);
 
 	/* Wait at least 1 ms */
-	msleep(1);
+	usleep_range(1000, 1100);
 
 	/* Power down setting 2 */
 	ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE);