[PATCH v3 10/11] platform/x86: int3472/discrete: Ensure the clk/power enable pins are in output mode

Hans de Goede
2022-12-16T11:32:27Z

acpi_get_and_request_gpiod() does not take a gpio_lookup_flags argument
specifying that the pins direction should be initialized to a specific
value.

This means that in some cases the pins might be left in input mode, causing
the gpiod_set() calls made to enable the clk / regulator to not work.

One example of this problem is the clk-enable GPIO for the ov01a1s sensor
on a Dell Latitude 9420 being left in input mode causing the clk to
never get enabled.

Explicitly set the direction of the pins to output to fix this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/platform/x86/intel/int3472/clk_and_regulator.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/platform/x86/intel/int3472/clk_and_regulator.c b/drivers/platform/x86/intel/int3472/clk_and_regulator.c
index 4b4d77db44ce..15a8bff645f7 100644
--- a/drivers/platform/x86/intel/int3472/clk_and_regulator.c
+++ b/drivers/platform/x86/intel/int3472/clk_and_regulator.c
@@ -106,6 +106,9 @@ int skl_int3472_register_clock(struct int3472_discrete_device *int3472,
return dev_err_probe(int3472->dev, ret, "getting regulator GPIO\n");
}

+ /* Ensure the pin is in output mode and non-active state */
+ gpiod_direction_output(int3472->clock.ena_gpio, 0);
+
init.name = kasprintf(GFP_KERNEL, "%s-clk",
acpi_dev_name(int3472->adev));
if (!init.name) {
@@ -198,6 +201,9 @@ int skl_int3472_register_regulator(struct int3472_discrete_device *int3472,
return PTR_ERR(int3472->regulator.gpio);
}

+ /* Ensure the pin is in output mode and non-active state */
+ gpiod_direction_output(int3472->regulator.gpio, 0);
+
cfg.dev = &int3472->adev->dev;
cfg.init_data = &init_data;
cfg.ena_gpiod = int3472->regulator.gpio;
--
2.38.1