Re: [PATCH 3/9] OMAP: HSMMC: Make fclk disable request driven.

[Tony Lindgren <tony@atomide.com>]

* Adrian Hunter <ext-adrian.hunter@nokia.com> [081121 01:16]:
> Start idle timer only at the end of request or request like operation
> such card detect, set_ios, probe, or resume. This will ensure the fclk is
> disable quickly after the operation is done, but never too early.

>From merging into mainline point of view, maybe this should be merged into
the earlier patch for adding the idle timer?

Tony

> Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
> ---
> drivers/mmc/host/omap_hsmmc.c |   15 ++++++++++-----
> 1 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 2eed691..a134f76 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -122,7 +122,7 @@
> 	__raw_writel((val), (base) + OMAP_HSMMC_##reg)
>
> enum {OFF = 0, ON};
> -#define IDLE_TIMEOUT (5*HZ)
> +#define IDLE_TIMEOUT (jiffies_to_msecs(10))
>
> struct mmc_omap_host {
> 	struct	device		*dev;
> @@ -165,6 +165,7 @@ static int mmc_omap_fclk_state(struct mmc_omap_host *host, unsigned int state)
> 	int ret = 0;
>
> 	spin_lock_irqsave(&host->clk_lock, flags);
> +	del_timer(&host->idle_timer);
> 	if (host->fclk_enabled != state) {
> 		if (state == ON) {
> 			ret = clk_enable(host->fclk);
> @@ -172,13 +173,9 @@ static int mmc_omap_fclk_state(struct mmc_omap_host *host, unsigned int state)
> 				goto err_out;
>
> 			dev_dbg(mmc_dev(host->mmc), "mmc_fclk: enabled\n");
> -			/* Revisit: Change the timer bump based on real
> -			   MMC usage characteristics */
> -			mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
> 		} else {
> 			clk_disable(host->fclk);
> 			dev_dbg(mmc_dev(host->mmc), "mmc_fclk: disabled\n");
> -			del_timer(&host->idle_timer);
> 		}
> 		host->fclk_enabled = state;
> 	}
> @@ -335,6 +332,7 @@ mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
>
> 	if (!data->stop) {
> 		host->mrq = NULL;
> +		mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
> 		mmc_request_done(host->mmc, data->mrq);
> 		return;
> 	}
> @@ -363,6 +361,7 @@ mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
> 	}
> 	if (host->data == NULL || cmd->error) {
> 		host->mrq = NULL;
> +		mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
> 		mmc_request_done(host->mmc, cmd->mrq);
> 	}
> }
> @@ -575,6 +574,7 @@ static void mmc_omap_detect(struct work_struct *work)
> 		while (OMAP_HSMMC_READ(host->base, SYSCTL) & SRD) ;
> 		mmc_detect_change(host->mmc, (HZ * 50) / 1000);
> 	}
> +	mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
> }
>
> /*
> @@ -874,6 +874,8 @@ static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>
> 	if (ios->power_mode == MMC_POWER_OFF)
> 		mmc_omap_fclk_state(host, OFF);
> +	else
> +		mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
> }
>
> static int omap_hsmmc_get_cd(struct mmc_host *mmc)
> @@ -1088,6 +1090,7 @@ static int __init omap_mmc_probe(struct platform_device *pdev)
> 		if (ret < 0)
> 			goto err_cover_switch;
> 	}
> +	mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
>
> 	return 0;
>
> @@ -1250,6 +1253,8 @@ static int omap_mmc_resume(struct platform_device *pdev)
> 		ret = mmc_resume_host(host->mmc);
> 		if (ret == 0)
> 			host->suspended = 0;
> +
> +		mod_timer(&host->idle_timer, jiffies + IDLE_TIMEOUT);
> 	}
>
> 	return ret;
> -- 
> 1.5.4.3