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
>
Attachment:
signature.asc
Description: PGP signature
