| Message ID | 20170726140246.4775-1-ludovic.desroches@microchip.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 26/07/17 17:02, Ludovic Desroches wrote: > When the device is non removable, the card detect signal is often use use -> used > for another purpose i.e. muxed to another SoC peripheral or used as a > GPIO. It could lead to wrong behaviors depending the defaut value of defaut -> default > this signal if not muxed to the SDHCI controller. > > Fixes: bb5f8ea4d514 ("mmc: sdhci-of-at91: introduce driver for the Atmel SDMMC") > Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com> Apart from spelling Acked-by: Adrian Hunter <adrian.hunter@intel.com> > --- > drivers/mmc/host/sdhci-of-at91.c | 36 +++++++++++++++++++++++++++++++++++- > 1 file changed, 35 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c > index 88e9b5f35a62..6a389f35396e 100644 > --- a/drivers/mmc/host/sdhci-of-at91.c > +++ b/drivers/mmc/host/sdhci-of-at91.c > @@ -31,6 +31,7 @@ > > #define SDMMC_MC1R 0x204 > #define SDMMC_MC1R_DDR BIT(3) > +#define SDMMC_MC1R_FCD BIT(7) > #define SDMMC_CACR 0x230 > #define SDMMC_CACR_CAPWREN BIT(0) > #define SDMMC_CACR_KEY (0x46 << 8) > @@ -44,6 +45,15 @@ struct sdhci_at91_priv { > bool restore_needed; > }; > > +static void sdhci_at91_set_force_card_detect(struct sdhci_host *host) > +{ > + u8 mc1r; > + > + mc1r = readb(host->ioaddr + SDMMC_MC1R); > + mc1r |= SDMMC_MC1R_FCD; > + writeb(mc1r, host->ioaddr + SDMMC_MC1R); > +} > + > static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) > { > u16 clk; > @@ -111,10 +121,18 @@ void sdhci_at91_set_uhs_signaling(struct sdhci_host *host, unsigned int timing) > sdhci_set_uhs_signaling(host, timing); > } > > +static void sdhci_at91_reset(struct sdhci_host *host, u8 mask) > +{ > + sdhci_reset(host, mask); > + > + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) > + sdhci_at91_set_force_card_detect(host); > +} > + > static const struct sdhci_ops sdhci_at91_sama5d2_ops = { > .set_clock = sdhci_at91_set_clock, > .set_bus_width = sdhci_set_bus_width, > - .reset = sdhci_reset, > + .reset = sdhci_at91_reset, > .set_uhs_signaling = sdhci_at91_set_uhs_signaling, > .set_power = sdhci_at91_set_power, > }; > @@ -369,6 +387,22 @@ static int sdhci_at91_probe(struct platform_device *pdev) > host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION; > } > > + /* > + * If the device attached to the MMC bus is not removable, it is safer > + * to set the Force Card Detect bit. People often don't connect the > + * card detect signal and use this pin for another purpose. If the card > + * detect pin is not muxed to SDHCI controller, a default value is > + * used. This value can be different from a SoC revision to another > + * one. Problems come when this default value is not card present. To > + * avoid this case, if the device is non removable then the card > + * detection procedure using the SDMCC_CD signal is bypassed. > + * This bit is resetted when a software reset for all command is resetted -> reset > + * performed so we need to implement our own reset function to set back > + * this bit. > + */ > + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) > + sdhci_at91_set_force_card_detect(host); > + > pm_runtime_put_autosuspend(&pdev->dev); > > return 0; > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 26 July 2017 at 16:02, Ludovic Desroches <ludovic.desroches@microchip.com> wrote: > When the device is non removable, the card detect signal is often use > for another purpose i.e. muxed to another SoC peripheral or used as a > GPIO. It could lead to wrong behaviors depending the defaut value of > this signal if not muxed to the SDHCI controller. > > Fixes: bb5f8ea4d514 ("mmc: sdhci-of-at91: introduce driver for the Atmel SDMMC") > Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com> Thanks, applied for fixes and added a stable tag. I also fixed some spellings according to the comments from Adrian. Kind regards Uffe > --- > drivers/mmc/host/sdhci-of-at91.c | 36 +++++++++++++++++++++++++++++++++++- > 1 file changed, 35 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c > index 88e9b5f35a62..6a389f35396e 100644 > --- a/drivers/mmc/host/sdhci-of-at91.c > +++ b/drivers/mmc/host/sdhci-of-at91.c > @@ -31,6 +31,7 @@ > > #define SDMMC_MC1R 0x204 > #define SDMMC_MC1R_DDR BIT(3) > +#define SDMMC_MC1R_FCD BIT(7) > #define SDMMC_CACR 0x230 > #define SDMMC_CACR_CAPWREN BIT(0) > #define SDMMC_CACR_KEY (0x46 << 8) > @@ -44,6 +45,15 @@ struct sdhci_at91_priv { > bool restore_needed; > }; > > +static void sdhci_at91_set_force_card_detect(struct sdhci_host *host) > +{ > + u8 mc1r; > + > + mc1r = readb(host->ioaddr + SDMMC_MC1R); > + mc1r |= SDMMC_MC1R_FCD; > + writeb(mc1r, host->ioaddr + SDMMC_MC1R); > +} > + > static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) > { > u16 clk; > @@ -111,10 +121,18 @@ void sdhci_at91_set_uhs_signaling(struct sdhci_host *host, unsigned int timing) > sdhci_set_uhs_signaling(host, timing); > } > > +static void sdhci_at91_reset(struct sdhci_host *host, u8 mask) > +{ > + sdhci_reset(host, mask); > + > + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) > + sdhci_at91_set_force_card_detect(host); > +} > + > static const struct sdhci_ops sdhci_at91_sama5d2_ops = { > .set_clock = sdhci_at91_set_clock, > .set_bus_width = sdhci_set_bus_width, > - .reset = sdhci_reset, > + .reset = sdhci_at91_reset, > .set_uhs_signaling = sdhci_at91_set_uhs_signaling, > .set_power = sdhci_at91_set_power, > }; > @@ -369,6 +387,22 @@ static int sdhci_at91_probe(struct platform_device *pdev) > host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION; > } > > + /* > + * If the device attached to the MMC bus is not removable, it is safer > + * to set the Force Card Detect bit. People often don't connect the > + * card detect signal and use this pin for another purpose. If the card > + * detect pin is not muxed to SDHCI controller, a default value is > + * used. This value can be different from a SoC revision to another > + * one. Problems come when this default value is not card present. To > + * avoid this case, if the device is non removable then the card > + * detection procedure using the SDMCC_CD signal is bypassed. > + * This bit is resetted when a software reset for all command is > + * performed so we need to implement our own reset function to set back > + * this bit. > + */ > + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) > + sdhci_at91_set_force_card_detect(host); > + > pm_runtime_put_autosuspend(&pdev->dev); > > return 0; > -- > 2.12.2 > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" 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/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c index 88e9b5f35a62..6a389f35396e 100644 --- a/drivers/mmc/host/sdhci-of-at91.c +++ b/drivers/mmc/host/sdhci-of-at91.c @@ -31,6 +31,7 @@ #define SDMMC_MC1R 0x204 #define SDMMC_MC1R_DDR BIT(3) +#define SDMMC_MC1R_FCD BIT(7) #define SDMMC_CACR 0x230 #define SDMMC_CACR_CAPWREN BIT(0) #define SDMMC_CACR_KEY (0x46 << 8) @@ -44,6 +45,15 @@ struct sdhci_at91_priv { bool restore_needed; }; +static void sdhci_at91_set_force_card_detect(struct sdhci_host *host) +{ + u8 mc1r; + + mc1r = readb(host->ioaddr + SDMMC_MC1R); + mc1r |= SDMMC_MC1R_FCD; + writeb(mc1r, host->ioaddr + SDMMC_MC1R); +} + static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) { u16 clk; @@ -111,10 +121,18 @@ void sdhci_at91_set_uhs_signaling(struct sdhci_host *host, unsigned int timing) sdhci_set_uhs_signaling(host, timing); } +static void sdhci_at91_reset(struct sdhci_host *host, u8 mask) +{ + sdhci_reset(host, mask); + + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) + sdhci_at91_set_force_card_detect(host); +} + static const struct sdhci_ops sdhci_at91_sama5d2_ops = { .set_clock = sdhci_at91_set_clock, .set_bus_width = sdhci_set_bus_width, - .reset = sdhci_reset, + .reset = sdhci_at91_reset, .set_uhs_signaling = sdhci_at91_set_uhs_signaling, .set_power = sdhci_at91_set_power, }; @@ -369,6 +387,22 @@ static int sdhci_at91_probe(struct platform_device *pdev) host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION; } + /* + * If the device attached to the MMC bus is not removable, it is safer + * to set the Force Card Detect bit. People often don't connect the + * card detect signal and use this pin for another purpose. If the card + * detect pin is not muxed to SDHCI controller, a default value is + * used. This value can be different from a SoC revision to another + * one. Problems come when this default value is not card present. To + * avoid this case, if the device is non removable then the card + * detection procedure using the SDMCC_CD signal is bypassed. + * This bit is resetted when a software reset for all command is + * performed so we need to implement our own reset function to set back + * this bit. + */ + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) + sdhci_at91_set_force_card_detect(host); + pm_runtime_put_autosuspend(&pdev->dev); return 0;
When the device is non removable, the card detect signal is often use for another purpose i.e. muxed to another SoC peripheral or used as a GPIO. It could lead to wrong behaviors depending the defaut value of this signal if not muxed to the SDHCI controller. Fixes: bb5f8ea4d514 ("mmc: sdhci-of-at91: introduce driver for the Atmel SDMMC") Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com> --- drivers/mmc/host/sdhci-of-at91.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-)