| Message ID | Pine.LNX.4.64.1304221611100.23906@axis700.grange (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
Hi Guennadi, Thanks for the patch. On Monday 22 April 2013 16:14:40 Guennadi Liakhovetski wrote: > With MMC clock gating enabled the MMC core currently calls MMC host driver's > .set_ios() method with .power_mode == MMC_POWER_ON and the clock value set > either to 0 or to the target rate. The tmio MMC driver then wrongly > translates the latter calls to card slot power-on requests, even when the > slot already was on. This patch fixes the driver to avoid needlessly > incrementing power-supplying regulator's use count. > > Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com> > > --- > drivers/mmc/host/tmio_mmc.h | 20 ++++++++++++++++++-- > drivers/mmc/host/tmio_mmc_pio.c | 16 +++++++++------- > 2 files changed, 27 insertions(+), 9 deletions(-) > > diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h > index d857f5c..3cc589a 100644 > --- a/drivers/mmc/host/tmio_mmc.h > +++ b/drivers/mmc/host/tmio_mmc.h > @@ -40,6 +40,22 @@ > > struct tmio_mmc_data; > > +/* > + * We differentiate between the following 3 power states: > + * 1. card slot powered off, controller stopped. This is used, when either > + * there is no card in the slot, or the card really has to be powered > + * down. > + * 2. card slot powered on, controller stopped. This is used, when a card > + * is in the slot, but no activity is currently taking place. This is a > + * power-saving mode with card-state preserved. This state can be > + * entered, e.g. when MMC clock-gating is used. > + * 3. card slot powered on, controller running. This is the actual active > + * state. > + */ > +enum tmio_mmc_power { > + TMIO_MMC_OFF_STOP, /* card power off, controller stopped */ > + TMIO_MMC_ON_STOP, /* card power on, controller stopped */ > + TMIO_MMC_ON_RUN, /* card power on, controller running */ > +}; > + > struct tmio_mmc_host { > void __iomem *ctl; > unsigned long bus_shift; > @@ -48,8 +64,8 @@ struct tmio_mmc_host { > struct mmc_data *data; > struct mmc_host *mmc; > > - /* Controller power state */ > - bool power; > + /* Controller and card power state */ > + enum tmio_mmc_power power; > > /* Callbacks for clock / power control */ > void (*set_pwr)(struct platform_device *host, int state); > diff --git a/drivers/mmc/host/tmio_mmc_pio.c > b/drivers/mmc/host/tmio_mmc_pio.c index f508ecb..d442eab 100644 > --- a/drivers/mmc/host/tmio_mmc_pio.c > +++ b/drivers/mmc/host/tmio_mmc_pio.c > @@ -859,25 +859,27 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, > struct mmc_ios *ios) * is kept positive, so no suspending actually takes > place. > */ > if (ios->power_mode == MMC_POWER_ON && ios->clock) { > - if (!host->power) { > + if (host->power != TMIO_MMC_ON_RUN) { > tmio_mmc_clk_update(mmc); > pm_runtime_get_sync(dev); > } > tmio_mmc_set_clock(host, ios->clock); > - if (!host->power) { > + if (host->power == TMIO_MMC_OFF_STOP) > /* power up SD card and the bus */ > tmio_mmc_power_on(host, ios->vdd); > - host->power = true; > - } > + host->power = TMIO_MMC_ON_RUN; > /* start bus clock */ > tmio_mmc_clk_start(host); > } else if (ios->power_mode != MMC_POWER_UP) { > if (host->power) { Maybe host->power != TMIO_MMC_OFF_STOP ? Otherwise the patch looks good to me. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > struct tmio_mmc_data *pdata = host->pdata; > - if (ios->power_mode == MMC_POWER_OFF) > + if (ios->power_mode == MMC_POWER_OFF) { > tmio_mmc_power_off(host); > + host->power = TMIO_MMC_OFF_STOP; > + } else { > + host->power = TMIO_MMC_ON_STOP; > + } > tmio_mmc_clk_stop(host); > - host->power = false; > pm_runtime_put(dev); > if (pdata->clk_disable) > pdata->clk_disable(host->pdev); > @@ -1025,7 +1027,7 @@ int tmio_mmc_host_probe(struct tmio_mmc_host **host, > mmc->caps & MMC_CAP_NONREMOVABLE || > mmc->slot.cd_irq >= 0); > > - _host->power = false; > + _host->power = TMIO_MMC_OFF_STOP; > pm_runtime_enable(&pdev->dev); > ret = pm_runtime_resume(&pdev->dev); > if (ret < 0)
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h index d857f5c..3cc589a 100644 --- a/drivers/mmc/host/tmio_mmc.h +++ b/drivers/mmc/host/tmio_mmc.h @@ -40,6 +40,22 @@ struct tmio_mmc_data; +/* + * We differentiate between the following 3 power states: + * 1. card slot powered off, controller stopped. This is used, when either there + * is no card in the slot, or the card really has to be powered down. + * 2. card slot powered on, controller stopped. This is used, when a card is in + * the slot, but no activity is currently taking place. This is a power- + * saving mode with card-state preserved. This state can be entered, e.g. + * when MMC clock-gating is used. + * 3. card slot powered on, controller running. This is the actual active state. + */ +enum tmio_mmc_power { + TMIO_MMC_OFF_STOP, /* card power off, controller stopped */ + TMIO_MMC_ON_STOP, /* card power on, controller stopped */ + TMIO_MMC_ON_RUN, /* card power on, controller running */ +}; + struct tmio_mmc_host { void __iomem *ctl; unsigned long bus_shift; @@ -48,8 +64,8 @@ struct tmio_mmc_host { struct mmc_data *data; struct mmc_host *mmc; - /* Controller power state */ - bool power; + /* Controller and card power state */ + enum tmio_mmc_power power; /* Callbacks for clock / power control */ void (*set_pwr)(struct platform_device *host, int state); diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c index f508ecb..d442eab 100644 --- a/drivers/mmc/host/tmio_mmc_pio.c +++ b/drivers/mmc/host/tmio_mmc_pio.c @@ -859,25 +859,27 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) * is kept positive, so no suspending actually takes place. */ if (ios->power_mode == MMC_POWER_ON && ios->clock) { - if (!host->power) { + if (host->power != TMIO_MMC_ON_RUN) { tmio_mmc_clk_update(mmc); pm_runtime_get_sync(dev); } tmio_mmc_set_clock(host, ios->clock); - if (!host->power) { + if (host->power == TMIO_MMC_OFF_STOP) /* power up SD card and the bus */ tmio_mmc_power_on(host, ios->vdd); - host->power = true; - } + host->power = TMIO_MMC_ON_RUN; /* start bus clock */ tmio_mmc_clk_start(host); } else if (ios->power_mode != MMC_POWER_UP) { if (host->power) { struct tmio_mmc_data *pdata = host->pdata; - if (ios->power_mode == MMC_POWER_OFF) + if (ios->power_mode == MMC_POWER_OFF) { tmio_mmc_power_off(host); + host->power = TMIO_MMC_OFF_STOP; + } else { + host->power = TMIO_MMC_ON_STOP; + } tmio_mmc_clk_stop(host); - host->power = false; pm_runtime_put(dev); if (pdata->clk_disable) pdata->clk_disable(host->pdev); @@ -1025,7 +1027,7 @@ int tmio_mmc_host_probe(struct tmio_mmc_host **host, mmc->caps & MMC_CAP_NONREMOVABLE || mmc->slot.cd_irq >= 0); - _host->power = false; + _host->power = TMIO_MMC_OFF_STOP; pm_runtime_enable(&pdev->dev); ret = pm_runtime_resume(&pdev->dev); if (ret < 0)
With MMC clock gating enabled the MMC core currently calls MMC host driver's .set_ios() method with .power_mode == MMC_POWER_ON and the clock value set either to 0 or to the target rate. The tmio MMC driver then wrongly translates the latter calls to card slot power-on requests, even when the slot already was on. This patch fixes the driver to avoid needlessly incrementing power-supplying regulator's use count. Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com> --- drivers/mmc/host/tmio_mmc.h | 20 ++++++++++++++++++-- drivers/mmc/host/tmio_mmc_pio.c | 16 +++++++++------- 2 files changed, 27 insertions(+), 9 deletions(-)