Re: [PATCH] soundwire: amd: add an error code check in amd_sdw_clock_stop_exit

[Pierre-Louis Bossart]

On 11/15/23 03:54, Su Hui wrote:
> Clang static analyzer complains that value stored to 'ret' is never read.
> Add an error code check and print an error message if 'readl_poll_timeout'
> failed.
> 
> Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx>
> ---
>  drivers/soundwire/amd_manager.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/soundwire/amd_manager.c b/drivers/soundwire/amd_manager.c
> index 3a99f6dcdfaf..f391b541f4b7 100644
> --- a/drivers/soundwire/amd_manager.c
> +++ b/drivers/soundwire/amd_manager.c
> @@ -1029,6 +1029,10 @@ static int amd_sdw_clock_stop_exit(struct amd_sdw_manager *amd_manager)
>  		ret = readl_poll_timeout(amd_manager->mmio + ACP_SW_CLK_RESUME_CTRL, val,
>  					 (val & AMD_SDW_CLK_RESUME_DONE), ACP_DELAY_US,
>  					 AMD_SDW_TIMEOUT);
> +		if (ret)
> +			dev_err(amd_manager->dev, "%s: timed out: %pe\n", __func__,
> +				ERR_PTR(ret));

Is this really the desired behavior?

This patch fixes the static analysis issue by logging the error code,
but does it make sense to continue resuming here and trying to exit from
the clock stop mode?

At this point a bus reset might be a more relevant behavior...

>  		if (val & AMD_SDW_CLK_RESUME_DONE) {
>  			writel(0, amd_manager->mmio + ACP_SW_CLK_RESUME_CTRL);
>  			ret = sdw_bus_exit_clk_stop(&amd_manager->bus);