Re: [PATCH] mmc: mediatek: make sure clock is enabled when executing ops->card_busy()

From: Ulf Hansson
Date: Fri Jan 29 2016 - 05:23:49 EST


On 28 January 2016 at 20:31, Chaotian Jing <chaotian.jing@xxxxxxxxxxxx> wrote:
> add pm_runtime_get_sync() before access MSDC_PS register

This isn't need as the mmc core does that when claiming the host, see
below commit.

>From that point there have been some additional fixup, as there were
actually some paths when to core invoked some of the host_ops
callbacks, without claiming the host. Although that should also have
been fixed now.

commit 9250aea76bfcbf4c2a7868e5566281bf2bb7af27
mmc: core: Enable runtime PM management of host devices

Kind regards
Uffe

>
> Signed-off-by: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>
> ---
> drivers/mmc/host/mtk-sd.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index 82a97ac..a56b16d 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -1054,13 +1054,15 @@ static int msdc_ops_switch_volt(struct mmc_host *mmc, struct mmc_ios *ios)
> static int msdc_card_busy(struct mmc_host *mmc)
> {
> struct msdc_host *host = mmc_priv(mmc);
> - u32 status = readl(host->base + MSDC_PS);
> + u32 status;
>
> - /* check if any pin between dat[0:3] is low */
> - if (((status >> 16) & 0xf) != 0xf)
> - return 1;
> + pm_runtime_get_sync(host->dev);
> + status = readl(host->base + MSDC_PS);
> + pm_runtime_mark_last_busy(host->dev);
> + pm_runtime_put_autosuspend(host->dev);
>
> - return 0;
> + /* check if any pin between dat[0:3] is low */
> + return !!(((status >> 16) & 0xf) != 0xf);
> }
>
> static void msdc_request_timeout(struct work_struct *work)
> --
> 1.8.1.1.dirty
>