| Message ID | 1398670860-30695-6-git-send-email-afenkart@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Monday 28 April 2014 01:11 PM, Andreas Fenkart wrote: > The am335x can't detect pending cirq in PM runtime suspend. > This patch reconfigures dat1 as a GPIO before going to suspend. > SDIO interrupts are detected with the GPIO, the GPIO will only wake > the module from suspend, SDIO irq detection will still happen through the > IP block. > > Idea of remuxing the pins by Tony Lindgren. Code contributions from > Tony Lindgren and Balaji T K <balajitk@ti.com> > > Signed-off-by: Andreas Fenkart <afenkart@gmail.com> > Signed-off-by: Tony Lindgren <tony@atomide.com> Thanks Andreas for the patch series. Few comments ... > > diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt > index ce80561..4767cd1 100644 > --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt > +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt > @@ -56,3 +56,54 @@ Examples: > &edma 25>; > dma-names = "tx", "rx"; > }; > + > +[workaround for missing swakeup on am33xx] > + > +This SOC is missing the swakeup line, it will not detect SDIO irq > +while in suspend. > + > + ------ > + | PRCM | > + ------ > + ^ | > + swakeup | | fclk > + | v > + ------ ------- ----- > + | card | -- CIRQ --> | hsmmc | -- IRQ --> | CPU | > + ------ ------- ----- > + > +In suspend the fclk is off and the module is disfunctional. Even > +register reads will fail. A small logic in the host will request > +fclk restore, when an external event is detected. Once the clock > +is restored, the host detects the event normally. Since am33xx > +doesn't have this line it never wakes from suspend. > + > +The workaround is to reconfigure the dat1 line as a GPIO upon > +suspend. To make this work, we need to set 1) the named pinctrl > +states "default", "idle" and "gpio_dat1", 2) the gpio detecting > +sdio irq in suspend and 3) the compatibe section, see example below. > +The MMC driver will then toggle between gpio_dat1 and default during > +the runtime. If configuration is incomplete, a warning message is > +emitted "falling back to polling". Mind not every application > +needs SDIO irq, e.g. MMC cards Affected chips are am335x, > +probably others > + > + > + mmc1: mmc@48060100 { > + compatible = "ti,am33xx-hsmmc"; > + ... > + interrupts-extended = <&intc 64 &gpio2 28 0>; > + ... > + pinctrl-names = "default", "idle", "sleep", "gpio_dat1" > + pinctrl-0 = <&mmc1_pins>; > + pinctrl-1 = <&mmc1_idle>; > + pinctrl-2 = <&mmc1_sleep>; > + pinctrl-3 = <&mmc1_cirq_pin>; > + ... > + }; > + > + mmc1_cirq_pin: pinmux_cirq_pin { > + pinctrl-single,pins = < > + 0x0f8 0x3f /* GPIO2_28 */ > + >; > + }; > diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c > index 9cc0d21..8661e1f 100644 > --- a/drivers/mmc/host/omap_hsmmc.c > +++ b/drivers/mmc/host/omap_hsmmc.c > @@ -213,7 +213,10 @@ struct omap_hsmmc_host { > #define AUTO_CMD23 (1 << 0) /* Auto CMD23 support */ > #define HSMMC_SDIO_IRQ_ENABLED (1 << 1) /* SDIO irq enabled */ > #define HSMMC_WAKE_IRQ_ENABLED (1 << 2) > +#define HSMMC_SWAKEUP_QUIRK (1 << 3) > struct omap_hsmmc_next next_data; > + struct pinctrl *pinctrl; > + struct pinctrl_state *gpio_pinmux; > struct omap_mmc_platform_data *pdata; > }; > > @@ -1744,8 +1747,28 @@ static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host) > * and need to remux SDIO DAT1 to GPIO for wake-up from idle. > */ > if (host->pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) { > - ret = -ENODEV; > - goto err; > + if (IS_ERR(host->dev->pins->default_state)) { > + dev_info(host->dev, "missing default pinctrl state\n"); > + ret = -EINVAL; > + goto err; > + } > + > + host->pinctrl = devm_pinctrl_get(host->dev); > + if (IS_ERR(host->pinctrl)) { > + dev_warn(host->dev, "no pinctrl handle\n"); > + ret = -ENODEV; > + goto err; > + } > + > + host->gpio_pinmux = pinctrl_lookup_state(host->pinctrl, > + "gpio_dat1"); > + if (IS_ERR(host->gpio_pinmux)) { > + dev_info(host->dev, "missing \"gpio_dat1\" pinctrl state\n"); > + ret = -ENODEV; > + goto err; > + } > + > + host->flags |= HSMMC_SWAKEUP_QUIRK; > } > > devres_remove_group(host->dev, NULL); > @@ -2438,7 +2461,10 @@ static int omap_hsmmc_runtime_suspend(struct device *dev) > goto abort; > } > > - pinctrl_pm_select_idle_state(dev); > + if (host->flags & HSMMC_SWAKEUP_QUIRK) > + pinctrl_select_state(host->pinctrl, host->gpio_pinmux); Why not combine "gpio_dat1" state and "idle", update documentation to have gpio remuxed in idle state for SoCs with swakeup quirk, Since I don't see any use case where both idle/gpio_pinmux are getting used. > + else > + pinctrl_pm_select_idle_state(dev); > > WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED); > enable_irq(host->wake_irq); > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt index ce80561..4767cd1 100644 --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt @@ -56,3 +56,54 @@ Examples: &edma 25>; dma-names = "tx", "rx"; }; + +[workaround for missing swakeup on am33xx] + +This SOC is missing the swakeup line, it will not detect SDIO irq +while in suspend. + + ------ + | PRCM | + ------ + ^ | + swakeup | | fclk + | v + ------ ------- ----- + | card | -- CIRQ --> | hsmmc | -- IRQ --> | CPU | + ------ ------- ----- + +In suspend the fclk is off and the module is disfunctional. Even +register reads will fail. A small logic in the host will request +fclk restore, when an external event is detected. Once the clock +is restored, the host detects the event normally. Since am33xx +doesn't have this line it never wakes from suspend. + +The workaround is to reconfigure the dat1 line as a GPIO upon +suspend. To make this work, we need to set 1) the named pinctrl +states "default", "idle" and "gpio_dat1", 2) the gpio detecting +sdio irq in suspend and 3) the compatibe section, see example below. +The MMC driver will then toggle between gpio_dat1 and default during +the runtime. If configuration is incomplete, a warning message is +emitted "falling back to polling". Mind not every application +needs SDIO irq, e.g. MMC cards Affected chips are am335x, +probably others + + + mmc1: mmc@48060100 { + compatible = "ti,am33xx-hsmmc"; + ... + interrupts-extended = <&intc 64 &gpio2 28 0>; + ... + pinctrl-names = "default", "idle", "sleep", "gpio_dat1" + pinctrl-0 = <&mmc1_pins>; + pinctrl-1 = <&mmc1_idle>; + pinctrl-2 = <&mmc1_sleep>; + pinctrl-3 = <&mmc1_cirq_pin>; + ... + }; + + mmc1_cirq_pin: pinmux_cirq_pin { + pinctrl-single,pins = < + 0x0f8 0x3f /* GPIO2_28 */ + >; + }; diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 9cc0d21..8661e1f 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -213,7 +213,10 @@ struct omap_hsmmc_host { #define AUTO_CMD23 (1 << 0) /* Auto CMD23 support */ #define HSMMC_SDIO_IRQ_ENABLED (1 << 1) /* SDIO irq enabled */ #define HSMMC_WAKE_IRQ_ENABLED (1 << 2) +#define HSMMC_SWAKEUP_QUIRK (1 << 3) struct omap_hsmmc_next next_data; + struct pinctrl *pinctrl; + struct pinctrl_state *gpio_pinmux; struct omap_mmc_platform_data *pdata; }; @@ -1744,8 +1747,28 @@ static int omap_hsmmc_configure_wake_irq(struct omap_hsmmc_host *host) * and need to remux SDIO DAT1 to GPIO for wake-up from idle. */ if (host->pdata->controller_flags & OMAP_HSMMC_SWAKEUP_MISSING) { - ret = -ENODEV; - goto err; + if (IS_ERR(host->dev->pins->default_state)) { + dev_info(host->dev, "missing default pinctrl state\n"); + ret = -EINVAL; + goto err; + } + + host->pinctrl = devm_pinctrl_get(host->dev); + if (IS_ERR(host->pinctrl)) { + dev_warn(host->dev, "no pinctrl handle\n"); + ret = -ENODEV; + goto err; + } + + host->gpio_pinmux = pinctrl_lookup_state(host->pinctrl, + "gpio_dat1"); + if (IS_ERR(host->gpio_pinmux)) { + dev_info(host->dev, "missing \"gpio_dat1\" pinctrl state\n"); + ret = -ENODEV; + goto err; + } + + host->flags |= HSMMC_SWAKEUP_QUIRK; } devres_remove_group(host->dev, NULL); @@ -2438,7 +2461,10 @@ static int omap_hsmmc_runtime_suspend(struct device *dev) goto abort; } - pinctrl_pm_select_idle_state(dev); + if (host->flags & HSMMC_SWAKEUP_QUIRK) + pinctrl_select_state(host->pinctrl, host->gpio_pinmux); + else + pinctrl_pm_select_idle_state(dev); WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED); enable_irq(host->wake_irq);