Re: [RESEND PATCH 1/3] i2c: added FUNC flag for unsupported clock stretching

["Nicola Corna" <nicola@corna.info>]

October 20 2015 5:35 PM, "Wolfram Sang" <wsa@the-dreams.de> wrote:
> On Wed, Sep 16, 2015 at 03:32:01PM +0200, Nicola Corna wrote:
> 
>> Added I2C_FUNC_NO_CLK_STRETCH, to be used when clock stretching is not
>> supported.
>> 
>> Signed-off-by: Nicola Corna <nicola@corna.info>
> 
> I think this should be rather a quirk than a functionality, i.e.
> I2C_AQ_NO_CLK_STRETCH. Agree?
> 
I didn't know about these quirks, thanks. I'll update the patches, please review them.

Nicola Corna
>> ---
>> Documentation/i2c/functionality | 1 +
>> include/uapi/linux/i2c.h | 1 +
>> 2 files changed, 2 insertions(+)
>> 
>> diff --git a/Documentation/i2c/functionality b/Documentation/i2c/functionality
>> index 4aae8ed..f53807e 100644
>> --- a/Documentation/i2c/functionality
>> +++ b/Documentation/i2c/functionality
>> @@ -21,6 +21,7 @@ For the most up-to-date list of functionality constants, please check
>> I2C_M_REV_DIR_ADDR and I2C_M_NO_RD_ACK
>> flags (which modify the I2C protocol!)
>> I2C_FUNC_NOSTART Can skip repeated start sequence
>> + I2C_FUNC_NO_CLK_STRETCH Does NOT support clock stretching
>> I2C_FUNC_SMBUS_QUICK Handles the SMBus write_quick command
>> I2C_FUNC_SMBUS_READ_BYTE Handles the SMBus read_byte command
>> I2C_FUNC_SMBUS_WRITE_BYTE Handles the SMBus write_byte command
>> diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h
>> index b0a7dd6..59e4b43 100644
>> --- a/include/uapi/linux/i2c.h
>> +++ b/include/uapi/linux/i2c.h
>> @@ -88,6 +88,7 @@ struct i2c_msg {
>> #define I2C_FUNC_SMBUS_PEC 0x00000008
>> #define I2C_FUNC_NOSTART 0x00000010 /* I2C_M_NOSTART */
>> #define I2C_FUNC_SLAVE 0x00000020
>> +#define I2C_FUNC_NO_CLK_STRETCH 0x00000040 /* No check for SCL low */
>> #define I2C_FUNC_SMBUS_BLOCK_PROC_CALL 0x00008000 /* SMBus 2.0 */
>> #define I2C_FUNC_SMBUS_QUICK 0x00010000
>> #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
>> --
>> 2.5.1