The sdhci controller on xilinx zynq devices will not function unless the CD bit is provided. http://www.xilinx.com/support/answers/61064.html In cases where it is impossible to provide the CD bit in hardware, setting the controller to test mode and then setting inserted to true will get the controller to function without the CD bit. When the device has the property xlnx-fails-without-test-cd the driver changes the controller to test mode and sets test inserted to true to make the controller function. Signed-off-by: Zach Brown <zach.brown@xxxxxx> --- drivers/mmc/host/sdhci-of-arasan.c | 34 +++++++++++++++++++++++++++++++++- drivers/mmc/host/sdhci.h | 2 ++ 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c index b6f4c1d..46be9d9 100644 --- a/drivers/mmc/host/sdhci-of-arasan.c +++ b/drivers/mmc/host/sdhci-of-arasan.c @@ -23,6 +23,7 @@ #include <linux/of_device.h> #include <linux/phy/phy.h> #include "sdhci-pltfm.h" +#include <linux/of.h> #define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c @@ -38,6 +39,10 @@ struct sdhci_arasan_data { struct clk *clk_ahb; struct phy *phy; + unsigned int arasan_quirks; /* Arasan deviations from spec */ + +/* Controller does not have CD wired and will not function normally without */ +#define SDHCI_ARASAN_QUIRK_FAILS_WITHOUT_TEST_CD BIT(0) }; static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host) @@ -79,12 +84,32 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock) } } +void sdhci_arasan_reset(struct sdhci_host *host, u8 mask) +{ + u8 ctrl; + struct sdhci_pltfm_host *pltfm_host; + struct sdhci_arasan_data *sdhci_arasan; + + sdhci_reset(host, mask); + + pltfm_host = sdhci_priv(host); + sdhci_arasan = sdhci_pltfm_priv(pltfm_host); + + if (sdhci_arasan->arasan_quirks & + SDHCI_ARASAN_QUIRK_FAILS_WITHOUT_TEST_CD) { + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); + ctrl |= SDHCI_CTRL_CDTEST_INS | + SDHCI_CTRL_CDTEST_EN; + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); + } +} + static struct sdhci_ops sdhci_arasan_ops = { .set_clock = sdhci_arasan_set_clock, .get_max_clock = sdhci_pltfm_clk_get_max_clock, .get_timeout_clock = sdhci_arasan_get_timeout_clock, .set_bus_width = sdhci_set_bus_width, - .reset = sdhci_reset, + .reset = sdhci_arasan_reset, .set_uhs_signaling = sdhci_set_uhs_signaling, }; @@ -179,6 +204,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev) struct sdhci_host *host; struct sdhci_pltfm_host *pltfm_host; struct sdhci_arasan_data *sdhci_arasan; + struct device_node *np = pdev->dev.of_node; host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata, sizeof(*sdhci_arasan)); @@ -215,6 +241,12 @@ static int sdhci_arasan_probe(struct platform_device *pdev) } sdhci_get_of_property(pdev); + + if (of_get_property(np, "xlnx-fails-without-test-cd", NULL)) { + sdhci_arasan->arasan_quirks |= + SDHCI_ARASAN_QUIRK_FAILS_WITHOUT_TEST_CD; + } + pltfm_host->clk = clk_xin; ret = mmc_of_parse(host->mmc); diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index 609f87c..60dbf1f 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_CDTEST_INS 0x40 +#define SDHCI_CTRL_CDTEST_EN 0x80 #define SDHCI_POWER_CONTROL 0x29 #define SDHCI_POWER_ON 0x01 -- 2.7.4 -- 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
