[PATCH] i2c: davinci: fix the cpufreq transition

[David Lechner]

On 01/22/2018 08:42 AM, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bgolaszewski at baylibre.com>
> 
> i2c_davinci_cpufreq_transition() is implemented in a way that will
> block if it ever gets called while no transfer is in progress.
> 
> Not only that, but reinit_completion() is never called for xfr_complete.
> 
> Use the fact that cpufreq uses an srcu_notifier (running in process
> context) for transitions and that the bus_lock is taken during the call
> to master_xfer() and simplify the code by removing the transfer
> completion entirely and protecting i2c_davinci_cpufreq_transition()
> with i2c_lock/unlock_adapter().
> 
> Reported-by: David Lechner <david at lechnology.com>
> Signed-off-by: Bartosz Golaszewski <bgolaszewski at baylibre.com>
> ---

Tested that it fixes the lockup when there is no active transfer.

Tested-by: David Lechner <david at lechnology.com>