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54836e2d03
On Tegra30 Cardhu the PCA9546 I2C mux is not ACK'ing I2C commands on resume from suspend (which is caused by the reset signal for the I2C mux not being configured correctl). However, this NACK is causing the Tegra30 to hang on resuming from suspend which is not expected as we detect NACKs and handle them. The hang observed appears to occur when resetting the I2C controller to recover from the NACK. Commit77821b4678("i2c: tegra: proper handling of error cases") added additional error handling for some error cases including NACK, however, it appears that this change conflicts with an early fix by commitf70893d083("i2c: tegra: Add delay before resetting the controller after NACK"). After commit77821b4678was made we now disable 'packet mode' before the delay from commitf70893d083happens. Testing shows that moving the delay to before disabling 'packet mode' fixes the hang observed on Tegra30. The delay was added to give the I2C controller chance to send a stop condition and so it makes sense to move this to before we disable packet mode. Please note that packet mode is always enabled for Tegra. Fixes:77821b4678("i2c: tegra: proper handling of error cases") Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@vger.kernel.org
Linux kernel
============
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See Documentation/00-INDEX for a list of what is contained in each file.
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