On 4 May 2016 at 13:38, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> Re-tuning is not possible when switched to the RPMB
> partition. However re-tuning should not be needed
> if re-tuning is done immediately before switching,
> a small set of operations is done, and then we
> immediately switch back to the main partition.
>
> To ensure that re-tuning can't be done for a short
> while, add a facility to "pause" re-tuning.
>
> The existing facility to hold / release re-tuning
> is used but it also flags re-tuning as needed to cause
> re-tuning before the next command (which will be the
> switch to RPMB).
>
> We also need to "unpause" in the recovery path, which
> is catered for by adding it to mmc_retune_disable().
>
> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> ---
> drivers/mmc/core/host.c | 22 ++++++++++++++++++++++
> include/linux/mmc/host.h | 4 ++++
> 2 files changed, 26 insertions(+)
>
> diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
> index e0a3ee16c0d3..302e5858755a 100644
> --- a/drivers/mmc/core/host.c
> +++ b/drivers/mmc/core/host.c
> @@ -68,8 +68,30 @@ void mmc_retune_enable(struct mmc_host *host)
> jiffies + host->retune_period * HZ);
> }
>
> +/*
> + * Pause re-tuning for a small set of operations. The pause begins after the
> + * next command and after first doing re-tuning.
> + */
> +void mmc_retune_pause(struct mmc_host *host)
> +{
> + if (!host->retune_paused) {
> + host->retune_paused = 1;
> + mmc_retune_needed(host);
> + mmc_retune_hold(host);
> + }
> +}
> +
When the mmc block device driver is built as a module, this doesn't
build. I will drop the series from my next branch to sort this out.
Should we export these via EXPORT_SYMBOL_GPL, or implement them as
inline functions?
This also made me think about the SDIO/WLAN driver issue, during
system PM suspend/resume, which also needed temporary to disable
re-tuning.
*If* we are going to export these, I want to make it works for the
SDIO case well...
Kind regards
Uffe
> +void mmc_retune_unpause(struct mmc_host *host)
> +{
> + if (host->retune_paused) {
> + host->retune_paused = 0;
> + mmc_retune_release(host);
> + }
> +}
> +
> void mmc_retune_disable(struct mmc_host *host)
> {
> + mmc_retune_unpause(host);
> host->can_retune = 0;
> del_timer_sync(&host->retune_timer);
> host->retune_now = 0;
> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
> index 85800b48241f..45cde8cd39f2 100644
> --- a/include/linux/mmc/host.h
> +++ b/include/linux/mmc/host.h
> @@ -329,6 +329,7 @@ struct mmc_host {
> unsigned int can_retune:1; /* re-tuning can be used */
> unsigned int doing_retune:1; /* re-tuning in progress */
> unsigned int retune_now:1; /* do re-tuning at next req */
> + unsigned int retune_paused:1; /* re-tuning is temporarily disabled */
>
> int rescan_disable; /* disable card detection */
> int rescan_entered; /* used with nonremovable devices */
> @@ -526,4 +527,7 @@ static inline void mmc_retune_recheck(struct mmc_host *host)
> host->retune_now = 1;
> }
>
> +void mmc_retune_pause(struct mmc_host *host);
> +void mmc_retune_unpause(struct mmc_host *host);
> +
> #endif /* LINUX_MMC_HOST_H */
> --
> 1.9.1
>
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
