Re: [PATCH] tmio_mmc_pio: prevent endless loop in tmio_mmc_set_clock()

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 05/04/2014 02:19 AM, Sergei Shtylyov wrote:

> I've spent a couple of days with the driver just hanging due to me forgetting
> to specify the external crystal frequency, so that clk_get_rate() returned 0
> and thus the loop in tmio_mmc_set_clock() never ended. I don't think that's an
> acceptable behavior, so I suggest that the minimum frequency is checked for 0
> in tmio_mmc_host_probe().

> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

> ---
> The patch is against Chris Ball's 'mmc.git' repo's 'master' branch.

    I'm still not seeing this patch applied anywhere in this repo... what's 
the problem with it?

>   drivers/mmc/host/tmio_mmc_pio.c |    9 +++++++++
>   1 file changed, 9 insertions(+)

> Index: mmc/drivers/mmc/host/tmio_mmc_pio.c
> ===================================================================
> --- mmc.orig/drivers/mmc/host/tmio_mmc_pio.c
> +++ mmc/drivers/mmc/host/tmio_mmc_pio.c
> @@ -1044,6 +1044,15 @@ int tmio_mmc_host_probe(struct tmio_mmc_
>   	}
>
>   	/*
> +	 * Check the sanity of mmc->f_min to prevent tmio_mmc_set_clock() from
> +	 * looping forever...
> +	 */
> +	if (mmc->f_min == 0) {
> +		ret = -EINVAL;
> +		goto pm_disable;
> +	}
> +
> +	/*
>   	 * There are 4 different scenarios for the card detection:
>   	 *  1) an external gpio irq handles the cd (best for power savings)
>   	 *  2) internal sdhi irq handles the cd

WBR, Sergei