Hi, Marek. your patch should be conflicted with "https://patchwork.kernel.org/patch/5698421/"; On 01/27/2015 05:11 PM, Marek Szyprowski wrote: > There are boards (like Hardkernel's Odroid boards) on which eMMC card's > reset line is connected to SoC GPIO line instead of the hardware reset > logic. In case of such boards, before performing system reboot, > additional reset of eMMC card is required to boot again properly. > This patch adds code for handling such cases. mmc core supported to hw_reset function. So i think we can use it. It's called at only initial time to clear the previous status. But i think it can be called at reboot time. (it needs to implement codes.) how about? Best Regards, Jaehoon Chung > > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > --- > .../devicetree/bindings/mmc/exynos-dw-mshc.txt | 6 +++ > drivers/mmc/host/dw_mmc-exynos.c | 43 +++++++++++++++++++++- > 2 files changed, 48 insertions(+), 1 deletion(-) > > diff --git a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt > index ee4fc0576c7d..fc53d335e7db 100644 > --- a/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt > +++ b/Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt > @@ -50,6 +50,12 @@ Required Properties: > - if CIU clock divider value is 0 (that is divide by 1), both tx and rx > phase shift clocks should be 0. > > +Optional properties: > + > +* dw-mshc-reset-gpios: optional property specifying gpio for the eMMC nreset > + line, it will be triggered on system reboot to properly reset eMMC card for > + next system boot. > + > Required properties for a slot (Deprecated - Recommend to use one slot per host): > > * gpios: specifies a list of gpios used for command, clock and data bus. The > diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c > index 509365cb22c6..2add5a93859d 100644 > --- a/drivers/mmc/host/dw_mmc-exynos.c > +++ b/drivers/mmc/host/dw_mmc-exynos.c > @@ -12,12 +12,14 @@ > #include <linux/module.h> > #include <linux/platform_device.h> > #include <linux/clk.h> > +#include <linux/delay.h> > #include <linux/mmc/host.h> > #include <linux/mmc/dw_mmc.h> > #include <linux/mmc/mmc.h> > #include <linux/of.h> > #include <linux/of_gpio.h> > #include <linux/slab.h> > +#include <linux/reboot.h> > > #include "dw_mmc.h" > #include "dw_mmc-pltfm.h" > @@ -77,8 +79,23 @@ struct dw_mci_exynos_priv_data { > u32 sdr_timing; > u32 ddr_timing; > u32 cur_speed; > + struct gpio_desc *reset_gpio; > + struct notifier_block reset_nb; > }; > > +static int dw_mci_restart_handler(struct notifier_block *this, > + unsigned long mode, void *cmd) > +{ > + struct dw_mci_exynos_priv_data *data; > + data = container_of(this, struct dw_mci_exynos_priv_data, reset_nb); > + > + gpiod_direction_output(data->reset_gpio, 0); > + mdelay(150); > + gpiod_direction_output(data->reset_gpio, 1); > + > + return NOTIFY_DONE; > +} > + > static struct dw_mci_exynos_compatible { > char *compatible; > enum dw_mci_exynos_type ctrl_type; > @@ -295,7 +312,20 @@ static int dw_mci_exynos_parse_dt(struct dw_mci *host) > return ret; > > priv->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0], timing[1], div); > + > + priv->reset_gpio = devm_gpiod_get_optional(host->dev, > + "samsung,dw-mshc-reset", > + GPIOD_OUT_HIGH); > + if (!IS_ERR_OR_NULL(priv->reset_gpio)) { > + priv->reset_nb.notifier_call = dw_mci_restart_handler; > + priv->reset_nb.priority = 255; > + ret = register_restart_handler(&priv->reset_nb); > + if (ret) > + dev_err(host->dev, "cannot register restart handler\n"); > + } > + > host->priv = priv; > + > return 0; > } > > @@ -490,6 +520,17 @@ static int dw_mci_exynos_probe(struct platform_device *pdev) > return dw_mci_pltfm_register(pdev, drv_data); > } > > +static int dw_mci_exynos_remove(struct platform_device *pdev) > +{ > + struct dw_mci *host = platform_get_drvdata(pdev); > + struct dw_mci_exynos_priv_data *priv = host->priv; > + > + if (priv->reset_gpio) > + unregister_restart_handler(&priv->reset_nb); > + > + return dw_mci_pltfm_remove(pdev); > +} > + > static const struct dev_pm_ops dw_mci_exynos_pmops = { > SET_SYSTEM_SLEEP_PM_OPS(dw_mci_exynos_suspend, dw_mci_exynos_resume) > .resume_noirq = dw_mci_exynos_resume_noirq, > @@ -499,7 +540,7 @@ static const struct dev_pm_ops dw_mci_exynos_pmops = { > > static struct platform_driver dw_mci_exynos_pltfm_driver = { > .probe = dw_mci_exynos_probe, > - .remove = __exit_p(dw_mci_pltfm_remove), > + .remove = dw_mci_exynos_remove, > .driver = { > .name = "dwmmc_exynos", > .of_match_table = dw_mci_exynos_match, > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
