OSDN Git Service

mmc: sdhci-pxav3: disable clock inversion for HS MMC cards
authorNadav Haklai <nadavh@marvell.com>
Tue, 6 Oct 2015 01:22:36 +0000 (03:22 +0200)
committerUlf Hansson <ulf.hansson@linaro.org>
Thu, 8 Oct 2015 17:24:23 +0000 (19:24 +0200)
According to 'FE-2946959' erratum the clock inversion option is
needed to support slow frequencies when the card input hold time
requirement is high. This setting is not required for high speed
MMC and might cause timing violation.

Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Cc: <stable@vger.kernel.org> # v4.2
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
drivers/mmc/host/sdhci-pxav3.c

index 976cddd..89a9e49 100644 (file)
@@ -291,6 +291,9 @@ static void pxav3_set_uhs_signaling(struct sdhci_host *host, unsigned int uhs)
                    uhs == MMC_TIMING_UHS_DDR50) {
                        reg_val &= ~SDIO3_CONF_CLK_INV;
                        reg_val |= SDIO3_CONF_SD_FB_CLK;
+               } else if (uhs == MMC_TIMING_MMC_HS) {
+                       reg_val &= ~SDIO3_CONF_CLK_INV;
+                       reg_val &= ~SDIO3_CONF_SD_FB_CLK;
                } else {
                        reg_val |= SDIO3_CONF_CLK_INV;
                        reg_val &= ~SDIO3_CONF_SD_FB_CLK;