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SubjectRe: [PATCHv5 1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms
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Hi

On 6/16/22 17:12, Dinh Nguyen wrote:
> The I2C pins on the SoCFPGA platforms do not go through a GPIO module,
> thus cannot be recovered by the default method of by doing a GPIO access.
> Only a reset of the I2C IP block can a recovery be successful.
>
One thing what is unclear to me how does this release the I2C slave that
potentially keeps the SDA stuck low. Does platform specific reset
sequence send 9 SCL pulses, toggle HW reset of the clients or cycle
power of them?

If recovery is only controller point of view then worth to emphasis it
in the commit log and perhaps add a comment too into
i2c_socfpga_scl_recovery(). Some might hit an issue that I2C client is
stuck and wonder why recovery won't work.

> The assignment of the recover_bus needs to get done before the call to
> devm_gpiod_get_optional(), otherwise, the assignment is not taking place
> because of an error after returning from devm_gpiod_get_optional().
>
This sentence no longer true after v3?

Otherwise code looks good to me.

Jarkko

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