Re: [PATCH] platform/x86: int3472: Add handshake GPIO function

[Hao Yao <hao.yao@intel.com>]

Thank you Bingbu,

On 2023/10/10 15:17, Bingbu Cao wrote:
> Hao,
> 
> On 10/7/23 10:12 AM, Hao Yao wrote:
>> Handshake pin is used for Lattice MIPI aggregator to enable the
>> camera sensor. After pulled up, recommend to wail ~250ms to get
>> everything ready.
> 
> Is the delay for specific camera or requirement from Lattice.
> 250ms is bad for camera.
> 

Actually the handshake pin is used by both Altek M1 and Lattice chips. 
As far as I know, Altek M1 required ~250ms delay while recently Lattice 
team told me they don't need delay. However I don't know if there were 
any devices using Altek M1.

>>
>> Signed-off-by: Hao Yao <hao.yao@intel.com>
>> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> ---
>>   drivers/platform/x86/intel/int3472/common.h   | 1 +
>>   drivers/platform/x86/intel/int3472/discrete.c | 5 +++++
>>   2 files changed, 6 insertions(+)
>>
>> diff --git a/drivers/platform/x86/intel/int3472/common.h b/drivers/platform/x86/intel/int3472/common.h
>> index 655ae3ec0593..3ad4c72afb45 100644
>> --- a/drivers/platform/x86/intel/int3472/common.h
>> +++ b/drivers/platform/x86/intel/int3472/common.h
>> @@ -23,6 +23,7 @@
>>   #define INT3472_GPIO_TYPE_POWER_ENABLE				0x0b
>>   #define INT3472_GPIO_TYPE_CLK_ENABLE				0x0c
>>   #define INT3472_GPIO_TYPE_PRIVACY_LED				0x0d
>> +#define INT3472_GPIO_TYPE_HANDSHAKE				0x12
>>   
>>   #define INT3472_PDEV_MAX_NAME_LEN				23
>>   #define INT3472_MAX_SENSOR_GPIOS				3
>> diff --git a/drivers/platform/x86/intel/int3472/discrete.c b/drivers/platform/x86/intel/int3472/discrete.c
>> index b644ce65c990..4753161b4080 100644
>> --- a/drivers/platform/x86/intel/int3472/discrete.c
>> +++ b/drivers/platform/x86/intel/int3472/discrete.c
>> @@ -111,6 +111,10 @@ static void int3472_get_func_and_polarity(u8 type, const char **func, u32 *polar
>>   		*func = "power-enable";
>>   		*polarity = GPIO_ACTIVE_HIGH;
>>   		break;
>> +	case INT3472_GPIO_TYPE_HANDSHAKE:
>> +		*func = "handshake";
>> +		*polarity = GPIO_ACTIVE_HIGH;
>> +		break;
>>   	default:
>>   		*func = "unknown";
>>   		*polarity = GPIO_ACTIVE_HIGH;
>> @@ -201,6 +205,7 @@ static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
>>   	switch (type) {
>>   	case INT3472_GPIO_TYPE_RESET:
>>   	case INT3472_GPIO_TYPE_POWERDOWN:
>> +	case INT3472_GPIO_TYPE_HANDSHAKE:
>>   		ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity);
>>   		if (ret)
>>   			err_msg = "Failed to map GPIO pin to sensor\n";
>>
> 


Best Regards,
Hao Yao