Re: [PATCH 2/3] media: atomisp-gc2235: drop an unused var

Nick Desaulniers
2021-11-15T17:55:31Z

On Mon, Nov 15, 2021 at 1:29 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Thu, Nov 11, 2021 at 11:08:52PM +0000, Mauro Carvalho Chehab wrote:
> > Fix this clang Werror with W=1:
> >
> > drivers/staging/media/atomisp/i2c/atomisp-gc2235.c:573:6: error: variable 'ret' set but not used [-Werror,-Wunused-but-set-variable]
> > int ret = -1;
> > ^
> >
> > Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> > ---
> >
>
> Looks good.
>
> There should be warning for "int x = -1;" followed by |= because that's
> a no-op OR assignment.
>
> I'm surprised that clang doesn't print errors about the other
> implementations of power_ctrl().

clang-tidy and scan-build will report dead stores. You may have seen
patches from reports from Abaci Robot which is running those checks
continuously.

>
> drivers/staging/media/atomisp/i2c/atomisp-mt9m114.c
> 448 static int power_ctrl(struct v4l2_subdev *sd, bool flag)
> 449 {
> 450 int ret;
> 451 struct mt9m114_device *dev = to_mt9m114_sensor(sd);
> 452
> 453 if (!dev || !dev->platform_data)
> 454 return -ENODEV;
> 455
> 456 if (flag) {
> 457 ret = dev->platform_data->v2p8_ctrl(sd, 1);
> 458 if (ret == 0) {
> 459 ret = dev->platform_data->v1p8_ctrl(sd, 1);
> 460 if (ret)
> 461 ret = dev->platform_data->v2p8_ctrl(sd, 0);
> 462 }
> 463 } else {
> 464 ret = dev->platform_data->v2p8_ctrl(sd, 0);
> 465 ret = dev->platform_data->v1p8_ctrl(sd, 0);
> ^^^^^^
>
> 466 }
> 467 return ret;
> 468 }
> 469
> 470 static int gpio_ctrl(struct v4l2_subdev *sd, bool flag)
> 471 {
> 472 int ret;
> 473 struct mt9m114_device *dev = to_mt9m114_sensor(sd);
> 474
> 475 if (!dev || !dev->platform_data)
> 476 return -ENODEV;
> 477
> 478 /*
> 479 * Note: current modules wire only one GPIO signal (RESET#),
> 480 * but the schematic wires up two to the connector. BIOS
> 481 * versions have been unfortunately inconsistent with which
> 482 * ACPI index RESET# is on, so hit both
> 483 */
> 484
> 485 if (flag) {
> 486 ret = dev->platform_data->gpio0_ctrl(sd, 0);
> 487 ret = dev->platform_data->gpio1_ctrl(sd, 0);
> ^^^^^^^
>
> 488 msleep(60);
> 489 ret |= dev->platform_data->gpio0_ctrl(sd, 1);
> 490 ret |= dev->platform_data->gpio1_ctrl(sd, 1);
> 491 } else {
>
> regards,
> dan carpenter
>

--
Thanks,
~Nick Desaulniers