platform/x86: int3472: Avoid GPIO regulator spikes

Avoid the GPIO controlling the avdd regulator being driven low or high
for a very short time leading to spikes by adding an enable delay of 2 ms
and a minimum off to on delay of also 2 ms.

Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>
Tested-by: David Heidelberg <[email protected]>  # Dell Latitude 9440
Reviewed-by: Sakari Ailus <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Ilpo Järvinen <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/platform/x86/intel/int3472/common.h b/drivers/platform/x86/intel/int3472/common.h
index 4bfd60df06de..2af8dc1ed25e 100644
--- a/drivers/platform/x86/intel/int3472/common.h
+++ b/drivers/platform/x86/intel/int3472/common.h
@@ -32,17 +32,27 @@
 #define GPIO_REGULATOR_NAME_LENGTH				(12 + GPIO_SUPPLY_NAME_LENGTH)
 /* lower- and upper-case mapping */
 #define GPIO_REGULATOR_SUPPLY_MAP_COUNT				2
+/*
+ * Ensure the GPIO is driven low/high for at least 2 ms before changing.
+ *
+ * 2 ms has been chosen because it is the minimum time ovXXXX sensors need to
+ * have their reset line driven logical high to properly register a reset.
+ */
+#define GPIO_REGULATOR_ENABLE_TIME				(2 * USEC_PER_MSEC)
+#define GPIO_REGULATOR_OFF_ON_DELAY				(2 * USEC_PER_MSEC)
 
 #define INT3472_LED_MAX_NAME_LEN				32
 
 #define CIO2_SENSOR_SSDB_MCLKSPEED_OFFSET			86
 
-#define INT3472_REGULATOR(_name, _ops)				\
+#define INT3472_REGULATOR(_name, _ops, _enable_time, _off_on_delay) \
 	(const struct regulator_desc) {				\
 		.name = _name,					\
 		.type = REGULATOR_VOLTAGE,			\
 		.ops = _ops,					\
 		.owner = THIS_MODULE,				\
+		.enable_time = _enable_time,			\
+		.off_on_delay = _off_on_delay,			\
 	}
 
 #define to_int3472_clk(hw)					\
@@ -134,6 +144,7 @@ void skl_int3472_unregister_clock(struct int3472_discrete_device *int3472);
 
 int skl_int3472_register_regulator(struct int3472_discrete_device *int3472,
 				   struct gpio_desc *gpio,
+				   unsigned int enable_time,
 				   const char *supply_name,
 				   const char *second_sensor);
 void skl_int3472_unregister_regulator(struct int3472_discrete_device *int3472);