[PATCH] rockchip: sdhci: rk3568: fix clock setting logic

[Kever Yang]

On 2023/3/8 05:26, Vasily Khoruzhick wrote:
> mmc->tran_speed is max clock, but currently rk3568_sdhci_set_ios_post
> uses it if its != 0, regardless of mmc->clock value, and it breaks
> eMMC controller.
>
> Without this patch 'mmc dev 0; mmc dev 1; mmc dev 0' is enough for
> breaking eMMC, since first initialization sets mmc->mmc_tran speed
> to non-zero value (26MHz in my case), and on subsequent re-init when
> mmc layer asks for 400KHz it sets 26MHz instead.
>
> Fix it by using MAX(mmc->tran_speed, mmc->clock)
>
> Signed-off-by: Vasily Khoruzhick <anarsoul at gmail.com>
Reviewed-by: Kever Yang <kever.yang at rock-chips.com>

Thanks,
- Kever
> ---
>   drivers/mmc/rockchip_sdhci.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mmc/rockchip_sdhci.c b/drivers/mmc/rockchip_sdhci.c
> index 9608770d4e..1ac95f32b3 100644
> --- a/drivers/mmc/rockchip_sdhci.c
> +++ b/drivers/mmc/rockchip_sdhci.c
> @@ -394,11 +394,11 @@ static int rk3568_sdhci_set_enhanced_strobe(struct sdhci_host *host)
>   static int rk3568_sdhci_set_ios_post(struct sdhci_host *host)
>   {
>   	struct mmc *mmc = host->mmc;
> -	uint clock = mmc->tran_speed;
> +	uint clock = mmc->clock;
>   	u32 reg, vendor_reg;
>   
> -	if (!clock)
> -		clock = mmc->clock;
> +	if (mmc->tran_speed && mmc->clock > mmc->tran_speed)
> +		clock = mmc->tran_speed;
>   
>   	rk3568_sdhci_emmc_set_clock(host, clock);
>