Re: [PATCH v2 3/4] hwmon/ltc2990: Add platform_data support

[Max Staudt]

On 08/13/2019 10:02 AM, Guenter Roeck wrote:
> On Tue, Aug 13, 2019 at 01:52:36AM +0200, Max Staudt wrote:
>> This allows code using i2c_new_device() to specify a measurement mode.
>>
>> Signed-off-by: Max Staudt <max@xxxxxxxxx>
>> Reviewed-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
>> ---
>>  drivers/hwmon/ltc2990.c               |  9 +++++++++
>>  include/linux/platform_data/ltc2990.h | 11 +++++++++++
>>  2 files changed, 20 insertions(+)
>>  create mode 100644 include/linux/platform_data/ltc2990.h
>>
>> diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
>> index f9431ad43..f19b9c50c 100644
>> --- a/drivers/hwmon/ltc2990.c
>> +++ b/drivers/hwmon/ltc2990.c
>> @@ -14,6 +14,7 @@
>>  #include <linux/kernel.h>
>>  #include <linux/module.h>
>>  #include <linux/of.h>
>> +#include <linux/platform_data/ltc2990.h>
>>  
>>  #define LTC2990_STATUS	0x00
>>  #define LTC2990_CONTROL	0x01
>> @@ -206,6 +207,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
>>  	int ret;
>>  	struct device *hwmon_dev;
>>  	struct ltc2990_data *data;
>> +	struct ltc2990_platform_data *pdata = dev_get_platdata(&i2c->dev);
>>  	struct device_node *of_node = i2c->dev.of_node;
>>  
>>  	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
>> @@ -227,6 +229,13 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
>>  		if (data->mode[0] & ~LTC2990_MODE0_MASK ||
>>  		    data->mode[1] & ~LTC2990_MODE1_MASK)
>>  			return -EINVAL;
>> +	} else if (pdata) {
>> +		data->mode[0] = pdata->meas_mode[0];
>> +		data->mode[1] = pdata->meas_mode[1];
>> +
>> +		if (data->mode[0] & ~LTC2990_MODE0_MASK ||
>> +		    data->mode[1] & ~LTC2990_MODE1_MASK)
>> +			return -EINVAL;
> 
> I would prefer if the driver was modified to accept device
> properties, and if those were set using the appropriate
> fwnode function. Any reason for not doing that ?

The driver does have DT support implemented right above my new platform_data code, and DT takes precedence. However, I can't set DT data programatically when instantiating the client using i2c_new_device() - hence the platform_data support.

Max