Re: [PATCH v5 08/11] mfd: cros_ec: Add convenience struct to define dedicated CrOS EC MCUs

[Enric Balletbo i Serra <enric.balletbo@collabora.com>]

Hi Lee,

On 12/8/19 9:16, Lee Jones wrote:
> On Mon, 22 Jul 2019, Enric Balletbo i Serra wrote:
> 
>> With the increasing use of dedicated CrOS EC MCUs, it takes a fair amount
>> of boiler plate code to add those devices, add a struct that can be used
>> to specify a dedicated CrOS EC MCU so we can just add a new item to it to
>> define a new dedicated MCU.
>>
>> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
>> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
>> Tested-by: Gwendal Grignou <gwendal@chromium.org>
>> ---
>>
>> Changes in v5: None
>> Changes in v4: None
>> Changes in v3: None
>> Changes in v2: None
>>
>>  drivers/mfd/cros_ec_dev.c | 87 +++++++++++++++++++++------------------
>>  1 file changed, 48 insertions(+), 39 deletions(-)
>>
>> diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
>> index c6bf52d795f2..e0e18c0eb9f5 100644
>> --- a/drivers/mfd/cros_ec_dev.c
>> +++ b/drivers/mfd/cros_ec_dev.c
>> @@ -22,6 +22,41 @@ static struct class cros_class = {
>>  	.name           = "chromeos",
>>  };
>>  
>> +/**
>> + * cros_feature_to_name - CrOS feature id to name/short description.
>> + * @id: The feature identifier.
>> + * @name: Device name associated with the feature id.
>> + * @desc: Short name that will be displayed.
>> + */
>> +struct cros_feature_to_name {
>> +	unsigned int id;
>> +	const char *name;
>> +	const char *desc;
>> +};
>> +
>> +static const struct cros_feature_to_name cros_mcu_devices[] = {
>> +	{
>> +		.id	= EC_FEATURE_FINGERPRINT,
>> +		.name	= CROS_EC_DEV_FP_NAME,
>> +		.desc	= "Fingerprint",
>> +	},
>> +	{
>> +		.id	= EC_FEATURE_ISH,
>> +		.name	= CROS_EC_DEV_ISH_NAME,
>> +		.desc	= "Integrated Sensor Hub",
>> +	},
>> +	{
>> +		.id	= EC_FEATURE_SCP,
>> +		.name	= CROS_EC_DEV_SCP_NAME,
>> +		.desc	= "System Control Processor",
>> +	},
>> +	{
>> +		.id	= EC_FEATURE_TOUCHPAD,
>> +		.name	= CROS_EC_DEV_TP_NAME,
>> +		.desc	= "Touchpad",
>> +	},
>> +};
>> +
>>  static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
>>  {
>>  	struct cros_ec_command *msg;
>> @@ -278,6 +313,7 @@ static int ec_device_probe(struct platform_device *pdev)
>>  	struct device *dev = &pdev->dev;
>>  	struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
>>  	struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL);
>> +	int i;
>>  
>>  	if (!ec)
>>  		return retval;
>> @@ -290,47 +326,20 @@ static int ec_device_probe(struct platform_device *pdev)
>>  	ec->features[1] = -1U; /* Not cached yet */
>>  	device_initialize(&ec->class_dev);
>>  
>> -	/* Check whether this is actually a Fingerprint MCU rather than an EC */
>> -	if (cros_ec_check_features(ec, EC_FEATURE_FINGERPRINT)) {
>> -		dev_info(dev, "CrOS Fingerprint MCU detected.\n");
>> -		/*
>> -		 * Help userspace differentiating ECs from FP MCU,
>> -		 * regardless of the probing order.
>> -		 */
>> -		ec_platform->ec_name = CROS_EC_DEV_FP_NAME;
>> -	}
>> -
>> -	/*
>> -	 * Check whether this is actually an Integrated Sensor Hub (ISH)
>> -	 * rather than an EC.
>> -	 */
>> -	if (cros_ec_check_features(ec, EC_FEATURE_ISH)) {
>> -		dev_info(dev, "CrOS ISH MCU detected.\n");
>> -		/*
>> -		 * Help userspace differentiating ECs from ISH MCU,
>> -		 * regardless of the probing order.
>> -		 */
>> -		ec_platform->ec_name = CROS_EC_DEV_ISH_NAME;
>> -	}
>> -
>> -	/* Check whether this is actually a Touchpad MCU rather than an EC */
>> -	if (cros_ec_check_features(ec, EC_FEATURE_TOUCHPAD)) {
>> -		dev_info(dev, "CrOS Touchpad MCU detected.\n");
>> +	for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
>>  		/*
>> -		 * Help userspace differentiating ECs from TP MCU,
>> -		 * regardless of the probing order.
>> +		 * Check whether this is actually a dedicated MCU rather
>> +		 * than an standard EC.
>>  		 */
>> -		ec_platform->ec_name = CROS_EC_DEV_TP_NAME;
>> -	}
>> -
>> -	/* Check whether this is actually a SCP rather than an EC. */
>> -	if (cros_ec_check_features(ec, EC_FEATURE_SCP)) {
>> -		dev_info(dev, "CrOS SCP MCU detected.\n");
>> -		/*
>> -		 * Help userspace differentiating ECs from SCP,
>> -		 * regardless of the probing order.
>> -		 */
>> -		ec_platform->ec_name = CROS_EC_DEV_SCP_NAME;
>> +		if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {
>> +			dev_info(dev, "CrOS %s MCU detected\n",
>> +				 cros_mcu_devices[i].desc);
>> +			/*
>> +			 * Help userspace differentiating ECs from other MCU,
>> +			 * regardless of the probing order.
>> +			 */
>> +			ec_platform->ec_name = cros_mcu_devices[i].name;
> 
> I assume by "dedicated MCU", you mean it can only support one of these
> at a time?  If so, please make that clear by adding a break statement
> once the MCU type has been determined.
> 

Right, will done in next version

Thanks,
Enric


>> +		}
>>  	}
>>  
>>  	/*
>