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SubjectRe: [PATCHv6 1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms
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Hi Wolfram,

On 6/22/22 15:07, Wolfram Sang wrote:
>
>> From the original code, the first mechanism to a recovery is to acquire a
>> GPIO for the SCL line and send the 9 SCL pulses, after that, it does a reset
>> of the I2C module. For the SOCFPGA part, there is no GPIO line for the SCL,
>> thus the I2C module cannot even get a reset. This code allows the function
>> to reset the I2C module for SOCFPGA, which is the 2nd part of the recovery
>> process.
>
> The second part is totally useless if the client device is holding SDA
> low. Which is exactly the situation that recovery tries to fix. As I
> said, if you can't control SCL, you don't have recovery.
>

This is recovery of the master and not the slave. We have a customer
that is the using I2C with the signals routed through the FPGA, and thus
are not GPIO. During a timeout, with this code, the driver is able to
recover the master.

Dinh

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