Re: [RESEND][PATCH] clk: at91: generated: Truncate divisor to GENERATED_MAX_DIV + 1

From: Nicolas.Ferre
Date: Wed Jul 03 2019 - 11:05:31 EST


On 25/06/2019 at 11:10, Codrin Ciubotariu wrote:
> In clk_generated_determine_rate(), if the divisor is greater than
> GENERATED_MAX_DIV + 1, then the wrong best_rate will be returned.
> If clk_generated_set_rate() will be called later with this wrong
> rate, it will return -EINVAL, so the generated clock won't change
> its value. Do no let the divisor be greater than GENERATED_MAX_DIV + 1.
>
> Fixes: 8c7aa6328947 ("clk: at91: clk-generated: remove useless divisor loop")
> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
> Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
> Acked-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
> ---
>
> - The email-server was converting my patches to base64, so I resend it
> using another server;
> - Added acked-bys from Nicolas and Ludovic;

Stephen,

I don't see this patch in linux-next and we're already late in the
development cycle: aka ping...

Best regards,
Nicolas

>
> drivers/clk/at91/clk-generated.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/clk/at91/clk-generated.c b/drivers/clk/at91/clk-generated.c
> index 5f18847965c1..290cffe35deb 100644
> --- a/drivers/clk/at91/clk-generated.c
> +++ b/drivers/clk/at91/clk-generated.c
> @@ -146,6 +146,8 @@ static int clk_generated_determine_rate(struct clk_hw *hw,
> continue;
>
> div = DIV_ROUND_CLOSEST(parent_rate, req->rate);
> + if (div > GENERATED_MAX_DIV + 1)
> + div = GENERATED_MAX_DIV + 1;
>
> clk_generated_best_diff(req, parent, parent_rate, div,
> &best_diff, &best_rate);
>


--
Nicolas Ferre