> -----Original Message----- > From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc- > owner@xxxxxxxxxxxxxxx] On Behalf Of Zach Brown > Sent: Tuesday, August 23, 2016 6:56 AM > To: adrian.hunter@xxxxxxxxx > Cc: ulf.hansson@xxxxxxxxxx; mark.rutland@xxxxxxx; robh+dt@xxxxxxxxxx; > linux-mmc@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx > Subject: [PATCH] sdhci: Add quirk and device tree parameter to force SD test > mode > > From: Jaeden Amero <jaeden.amero@xxxxxx> > > On some devices, CD is broken so that we must force the SDHCI into test mode > and set CD, so that it always detects an SD card as present. > > In order to get a device with broken CD working, we had previously always set > the SDHCI into test mode. Unfortunately, this had the side effect of making all > SD cards used with our Linux kernels undetectable and non-removable. Why not use the poll mode? You can set the flag MMC_CAP_NEEDS_POLL, then the mmc core will detect the card every second. > > By making this "SD test mode" setting optional via a quirk, we can avoid this > side effect for devices other than the device with broken CD. > Additionally, we add a device parameter to sdhci-pltfm to allow all SDHCI > drivers to enable this quirk. > > Signed-off-by: Jaeden Amero <jaeden.amero@xxxxxx> > Signed-off-by: Zach Brown <zach.brown@xxxxxx> > --- > Documentation/devicetree/bindings/mmc/mmc.txt | 2 ++ > drivers/mmc/host/sdhci-pltfm.c | 4 ++++ > drivers/mmc/host/sdhci.c | 9 +++++++++ > drivers/mmc/host/sdhci.h | 4 ++++ > 4 files changed, 19 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt > b/Documentation/devicetree/bindings/mmc/mmc.txt > index 22d1e1f..3a9be41 100644 > --- a/Documentation/devicetree/bindings/mmc/mmc.txt > +++ b/Documentation/devicetree/bindings/mmc/mmc.txt > @@ -52,6 +52,8 @@ Optional properties: > - no-sdio: controller is limited to send sdio cmd during initialization > - no-sd: controller is limited to send sd cmd during initialization > - no-mmc: controller is limited to send mmc cmd during initialization > +- force-sd-cd-test-mode: card detection is broken on device, force cd > +test > + enable and cd test inserted so host will always detect a card. > > *NOTE* on CD and WP polarity. To use common for all SD/MMC host > controllers line polarity properties, we have to fix the meaning of the "normal" > and "inverted" > diff --git a/drivers/mmc/host/sdhci-pltfm.c b/drivers/mmc/host/sdhci-pltfm.c > index 1d17dcf..056d101 100644 > --- a/drivers/mmc/host/sdhci-pltfm.c > +++ b/drivers/mmc/host/sdhci-pltfm.c > @@ -87,6 +87,10 @@ void sdhci_get_of_property(struct platform_device > *pdev) > if (of_get_property(np, "broken-cd", NULL)) > host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION; > > + if (of_get_property(np, "force-sd-cd-test-mode", NULL)) > + host->quirks2 |= > + SDHCI_QUIRK2_MUST_FORCE_SD_CD_TEST_MODE; > + > if (of_get_property(np, "no-1-8-v", NULL)) > host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V; > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index > cd65d47..2f4c6f9 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -117,6 +117,15 @@ static inline bool sdhci_data_line_cmd(struct > mmc_command *cmd) static void sdhci_set_card_detection(struct sdhci_host > *host, bool enable) { > u32 present; > + u8 ctrl; > + > + if (host->quirks2 & SDHCI_QUIRK2_MUST_FORCE_SD_CD_TEST_MODE) > { > + /* Put the card in test mode, with card inserted */ > + ctrl = sdhci_readl(host, SDHCI_HOST_CONTROL); > + ctrl |= SDHCI_CTRL_CD_TEST_INSERTED | > + SDHCI_CTRL_CD_TEST_ENABLE; > + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); > + } > > if ((host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) || > !mmc_card_is_removable(host->mmc)) > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index > 0411c9f..dd609b2 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -84,6 +84,8 @@ > #define SDHCI_CTRL_ADMA32 0x10 > #define SDHCI_CTRL_ADMA64 0x18 > #define SDHCI_CTRL_8BITBUS 0x20 > +#define SDHCI_CTRL_CD_TEST_INSERTED 0x40 > +#define SDHCI_CTRL_CD_TEST_ENABLE 0x80 > > #define SDHCI_POWER_CONTROL 0x29 > #define SDHCI_POWER_ON 0x01 > @@ -422,6 +424,8 @@ struct sdhci_host { > #define SDHCI_QUIRK2_ACMD23_BROKEN (1<<14) > /* Broken Clock divider zero in controller */ > #define SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN (1<<15) > +/* Controller must support device with broken CD */ > +#define SDHCI_QUIRK2_MUST_FORCE_SD_CD_TEST_MODE (1<<16) > > int irq; /* Device IRQ */ > void __iomem *ioaddr; /* Mapped address */ > -- > 2.7.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the > body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at > http://vger.kernel.org/majordomo-info.html -- 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
