Re: [PATCH v3 1/2] bus: mhi: Fix pm_state conversion to string

[Manivannan Sadhasivam <mani@kernel.org>]

On Tue, Jun 29, 2021 at 03:53:56PM +1200, Paul Davey wrote:
> On big endian architectures the mhi debugfs files which report pm state
> give "Invalid State" for all states.  This is caused by using
> find_last_bit which takes an unsigned long* while the state is passed in
> as an enum mhi_pm_state which will be of int size.
> 
> Fix by using __fls to pass the value of state instead of find_last_bit.
> 
> Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>

Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>

Thanks,
Mani

> ---
>  drivers/bus/mhi/core/init.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index c81b377fca8f..0706eb046f2a 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -79,9 +79,12 @@ static const char * const mhi_pm_state_str[] = {
>  
>  const char *to_mhi_pm_state_str(enum mhi_pm_state state)
>  {
> -	int index = find_last_bit((unsigned long *)&state, 32);
> +	int index;
>  
> -	if (index >= ARRAY_SIZE(mhi_pm_state_str))
> +	if (state)
> +		index = __fls(state);
> +
> +	if (!state || index >= ARRAY_SIZE(mhi_pm_state_str))
>  		return "Invalid State";
>  
>  	return mhi_pm_state_str[index];
> -- 
> 2.32.0
>