Rectify the logical value of reset-gpio so that it is set to
0 (disabled) during power-on and to 1 (enabled) during power-off.
Set the reset-gpio to GPIO_OUT_HIGH at initialization time to make
sure it starts off in reset. Also drop the "Set XCLR" comment which
is not-so-informative.
The existing usage of imx335 had reset-gpios polarity inverted
(GPIO_ACTIVE_HIGH) in their device-tree sources. With this patch
included, those DTS will not be able to stream imx335 anymore. The
reset-gpio polarity will need to be rectified in the device-tree
sources as shown in [1] example, in order to get imx335 functional
again (as it remains in reset prior to this fix).
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 45d19b5fb9ae ("media: i2c: Add imx335 camera sensor driver")
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/linux-media/20240729110437.199428-1-umang.jain@xxxxxxxxxxxxxxxx/
Signed-off-by: Umang Jain <umang.jain@xxxxxxxxxxxxxxxx>
---
Following conclusions has been observed and discussed [2]:
- Original driver was reviewed [3] but, the improper handling of
reset-gpios was missed in review.
- Commit fea91ee73b7c ("media: i2c: imx335: Enable regulator supplies")
shows the driver didn't had regulator enablement support. The driver
would have only worked for cases when the supplies were always-on.
- Commit 14a60786d72e ("media: imx335: Set reserved register to default value")
reflects that the imx335 driver was un-usable due to a reserved
register not been set to default.
- The original author is no longer using the driver nor it is used for its
original purpose any more (confirmed by Sakari Ailus).
- It's extremely unlikely the driver has been or continues to be in
use on ACPI based systems (comment by Sakari Ailus).
The above discussion points in a direction that driver does not cater
to a large user-base. Nonetheless, the breakage will be noticed by a few
users (if at all) hence, this explanation would help resolve the breakage
as soon as noticed (by using correct reset-gpio polarity as mentioned
in [1]).
[1]: Documentation/devicetree/bindings/media/i2c/sony,imx335.yaml
[2]: https://lore.kernel.org/linux-media/20240729110437.199428-1-umang.jain@xxxxxxxxxxxxxxxx/
[3]: https://lore.kernel.org/all/20210527142145.173-3-martinax.krasteva@xxxxxxxxxxxxxxx/
---
---
drivers/media/i2c/imx335.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/media/i2c/imx335.c b/drivers/media/i2c/imx335.c
index 990d74214cc2..54a1de53d497 100644
--- a/drivers/media/i2c/imx335.c
+++ b/drivers/media/i2c/imx335.c
@@ -997,7 +997,7 @@ static int imx335_parse_hw_config(struct imx335 *imx335)
/* Request optional reset pin */
imx335->reset_gpio = devm_gpiod_get_optional(imx335->dev, "reset",
- GPIOD_OUT_LOW);
+ GPIOD_OUT_HIGH);
if (IS_ERR(imx335->reset_gpio)) {
dev_err(imx335->dev, "failed to get reset gpio %ld\n",
PTR_ERR(imx335->reset_gpio));
@@ -1110,8 +1110,7 @@ static int imx335_power_on(struct device *dev)
usleep_range(500, 550); /* Tlow */
- /* Set XCLR */
- gpiod_set_value_cansleep(imx335->reset_gpio, 1);
+ gpiod_set_value_cansleep(imx335->reset_gpio, 0);
ret = clk_prepare_enable(imx335->inclk);
if (ret) {
@@ -1124,7 +1123,7 @@ static int imx335_power_on(struct device *dev)
return 0;
error_reset:
- gpiod_set_value_cansleep(imx335->reset_gpio, 0);
+ gpiod_set_value_cansleep(imx335->reset_gpio, 1);
regulator_bulk_disable(ARRAY_SIZE(imx335_supply_name), imx335->supplies);
return ret;
@@ -1141,7 +1140,7 @@ static int imx335_power_off(struct device *dev)
struct v4l2_subdev *sd = dev_get_drvdata(dev);
struct imx335 *imx335 = to_imx335(sd);
- gpiod_set_value_cansleep(imx335->reset_gpio, 0);
+ gpiod_set_value_cansleep(imx335->reset_gpio, 1);
clk_disable_unprepare(imx335->inclk);
regulator_bulk_disable(ARRAY_SIZE(imx335_supply_name), imx335->supplies);
--
2.45.0
