Re: [PATCH v2] mmc: sdhci-of-arasan: fix set_clock when a phy is supported

Adrian Hunter
2016-04-28T10:14:35Z

On 28/04/16 11:38, Shawn Lin wrote:
> commit 61b914eb81f8 ("mmc: sdhci-of-arasan: add phy support for
> sdhci-of-arasan") introduce phy support for arasan. According to
> the vendor's databook, we should make sure the phy is in poweroff
> status before we configure the clk stuff. Otherwise it may cause
> some IO sample timing issues from the test. And we don't need this
> extra operation while running in low performance mode since phy
> doesn't trigger sampling block.
>
> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

>
> ---
>
> Changes in v2:
> - change commit msg title to indicate it's a fix
> - fix a typo in commmit msg
>
> drivers/mmc/host/sdhci-of-arasan.c | 20 +++++++++++++++++++-
> 1 file changed, 19 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
> index 2e482b1..20b859e 100644
> --- a/drivers/mmc/host/sdhci-of-arasan.c
> +++ b/drivers/mmc/host/sdhci-of-arasan.c
> @@ -55,8 +55,26 @@ static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
> return freq;
> }
>
> +static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
> + bool ctrl_phy = false;
> +
> + if (clock > MMC_HIGH_52_MAX_DTR && (!IS_ERR(sdhci_arasan->phy)))
> + ctrl_phy = true;
> +
> + if (ctrl_phy)
> + phy_power_off(sdhci_arasan->phy);
> +
> + sdhci_set_clock(host, clock);
> +
> + if (ctrl_phy)
> + phy_power_on(sdhci_arasan->phy);
> +}
> +
> static struct sdhci_ops sdhci_arasan_ops = {
> - .set_clock = sdhci_set_clock,
> + .set_clock = sdhci_arasan_set_clock,
> .get_max_clock = sdhci_pltfm_clk_get_max_clock,
> .get_timeout_clock = sdhci_arasan_get_timeout_clock,
> .set_bus_width = sdhci_set_bus_width,
>