[PATCH] media: i2c: adv7842: Replace mdelay() with msleep() and usleep_range() in adv7842_ddr_ram_test()

From: Jia-Ju Bai
Date: Thu Jul 26 2018 - 22:59:23 EST


adv7842_ddr_ram_test() is never called in atomic context.
It only calls from:
adv7842_ddr_ram_test() <- adv7842_command_ram_test() <- adv7842_ioctl()

adv7842_ddr_ram_test() calls mdelay() to busily wait,
which is not necessary.
mdelay() can be replaced with msleep() and usleep_range().

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
drivers/media/i2c/adv7842.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/i2c/adv7842.c b/drivers/media/i2c/adv7842.c
index fddac32e5051..74ed32f77d5f 100644
--- a/drivers/media/i2c/adv7842.c
+++ b/drivers/media/i2c/adv7842.c
@@ -3102,7 +3102,7 @@ static int adv7842_ddr_ram_test(struct v4l2_subdev *sd)
sdp_write(sd, 0x12, 0x00); /* Disable 3D comb, Frame TBC & 3DNR */
io_write(sd, 0xFF, 0x04); /* Reset memory controller */

- mdelay(5);
+ usleep_range(5000, 6000);

sdp_write(sd, 0x12, 0x00); /* Disable 3D Comb, Frame TBC & 3DNR */
sdp_io_write(sd, 0x2A, 0x01); /* Memory BIST Initialisation */
@@ -3116,12 +3116,12 @@ static int adv7842_ddr_ram_test(struct v4l2_subdev *sd)
sdp_io_write(sd, 0x7d, 0x00); /* Memory BIST Initialisation */
sdp_io_write(sd, 0x7e, 0x1a); /* Memory BIST Initialisation */

- mdelay(5);
+ usleep_range(5000, 6000);

sdp_io_write(sd, 0xd9, 0xd5); /* Enable BIST Test */
sdp_write(sd, 0x12, 0x05); /* Enable FRAME TBC & 3D COMB */

- mdelay(20);
+ msleep(20);

for (i = 0; i < 10; i++) {
u8 result = sdp_io_read(sd, 0xdb);
@@ -3132,7 +3132,7 @@ static int adv7842_ddr_ram_test(struct v4l2_subdev *sd)
else
pass++;
}
- mdelay(20);
+ msleep(20);
}

v4l2_dbg(1, debug, sd,
--
2.17.0