[PATCH 2/8] mmc: sdhci-pxav3: disable clock inversion for HS MMC cards
From: Gregory CLEMENT <hidden>
Date: 2015-10-06 14:45:36
Also in:
linux-mmc, lkml, stable
Hi Marcin, On mar., oct. 06 2015, Marcin Wojtas [off-list ref] wrote:
From: Nadav Haklai <redacted> 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 <redacted> Cc: <redacted> # v4.2
Seems OK too. Reviewed-by: Gregory CLEMENT <redacted> Thanks, Gregory
quoted hunk
--- drivers/mmc/host/sdhci-pxav3.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c index 976cddd..89a9e49 100644 --- a/drivers/mmc/host/sdhci-pxav3.c +++ b/drivers/mmc/host/sdhci-pxav3.c@@ -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;-- 1.8.3.1
-- Gregory Clement, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com