From: Hans de Goede <hdegoede@xxxxxxxxxx>
media: ov08x40: Fix value of reset GPIO when requesting it
Upstream-status: Landed in media-committers/next
We should put/leave the sensor in reset when requesting the GPIO, after
requesting it there are 2 possible scenarios and having the GPIO driven
low is no good in either scenario:
1. The sensor was in ACPI D0 before probe() runs, in this case
ov08x40_power_on() + ov08x40_identify_module() will run immediately
after requesting the GPIO and ov08x40_power_on() starts with driving
the GPIO high. So if the GPIO was already high it will very shortly
be driven low, more of a spike to low then actually properly be driven
low. Which may leave the sensor in a confused state.
If we request the GPIO to be high at request time then power_on() will
driver it high again (no-op) and then sleep for 1-2 ms, so no spike.
2. The sensor was in ACPI D3 / off before probe(), in this case probe()
leaves the sensor alone. But when the sensor is off its reset line
should be driven high not low.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
diff --git a/drivers/media/i2c/ov08x40.c b/drivers/media/i2c/ov08x40.c
index blahblah..blahblah 100644
--- a/drivers/media/i2c/ov08x40.c
+++ b/drivers/media/i2c/ov08x40.c
@@ -2167,7 +2167,7 @@ static int ov08x40_check_hwcfg(struct ov08x40 *ov08x, struct device *dev)
return dev_err_probe(dev, ret, "parsing endpoint failed\n");
ov08x->reset_gpio = devm_gpiod_get_optional(dev, "reset",
- GPIOD_OUT_LOW);
+ GPIOD_OUT_HIGH);
if (IS_ERR(ov08x->reset_gpio)) {
ret = dev_err_probe(dev, PTR_ERR(ov08x->reset_gpio),
"getting reset GPIO\n");
--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3726
--
_______________________________________________
kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx
Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: https://lists.fedoraproject.org/archives/list/kernel@xxxxxxxxxxxxxxxxxxxxxxx
Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
