Re: [PATCH] i2c: i2c-stm32f7: Add I2C_SMBUS_I2C_BLOCK_DATA support

[Pierre Yves MORDRET]

Hi

I looks good to me

Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@xxxxxx>

Thx

On 6/26/19 3:45 PM, Wolfram Sang wrote:
> On Tue, Jun 04, 2019 at 03:20:51PM +0200, Fabrice Gasnier wrote:
>> This patch adds the support of I2C_SMBUS_I2C_BLOCK_DATA transaction type
>> for the stm32f7 SMBUS Controller.
>> Use emulated I2C_SMBUS_I2C_BLOCK_DATA transactions as there is no specific
>> hardware in STM32 I2C to manage this (e.g. like no need for PEC here).
>> Emulated transfer will fall back calling i2c transfer method where there's
>> already support for DMAs for example.
>> So, use the I2C_FUNC_SMBUS_I2C_BLOCK in stm32f7_i2c_func(), and rely on
>> emulated transfer by returning -EOPNOTSUPP in the smbus_xfer() routine
>> for such a case.
>>
>> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx>
> 
> Maintainers?
> 
>> ---
>>  drivers/i2c/busses/i2c-stm32f7.c | 6 +++++-
>>  1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
>> index 48337be..68a751e 100644
>> --- a/drivers/i2c/busses/i2c-stm32f7.c
>> +++ b/drivers/i2c/busses/i2c-stm32f7.c
>> @@ -953,6 +953,9 @@ static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
>>  		cr2 &= ~STM32F7_I2C_CR2_RD_WRN;
>>  		f7_msg->read_write = I2C_SMBUS_READ;
>>  		break;
>> +	case I2C_SMBUS_I2C_BLOCK_DATA:
>> +		/* Rely on emulated i2c transfer (through master_xfer) */
>> +		return -EOPNOTSUPP;
>>  	default:
>>  		dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size);
>>  		return -EOPNOTSUPP;
>> @@ -1803,7 +1806,8 @@ static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
>>  		I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
>>  		I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
>>  		I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
>> -		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC;
>> +		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC |
>> +		I2C_FUNC_SMBUS_I2C_BLOCK;
>>  }
>>  
>>  static struct i2c_algorithm stm32f7_i2c_algo = {
>> -- 
>> 2.7.4
>>