Browse Source

mmc: sdhci: fix bus width switching on Samsung SoCs

Fix bus width switching from 8-bit mode down to 4-bit or 1-bit modes on
Samsung SoCs using SDHCI_QUIRK_USE_WIDE8.  These SoCs report controller
version 2.0 yet they support 8-bit bus widths.  If 8-bit mode was
previously enabled and then an operation like "mmc dev" caused a switch
back down to 4-bit or 1-bit mode, WIDE8 was left set, causing failures.

This problem was manifested by "mmc dev" timing out.

Signed-off-by: Matt Reimer <mreimer@sdgsystems.com>
Matt Reimer 10 years ago
parent
commit
f88a429f11
1 changed files with 2 additions and 1 deletions
  1. 2 1
      drivers/mmc/sdhci.c

+ 2 - 1
drivers/mmc/sdhci.c

@@ -374,7 +374,8 @@ static void sdhci_set_ios(struct mmc *mmc)
 				(host->quirks & SDHCI_QUIRK_USE_WIDE8))
 				(host->quirks & SDHCI_QUIRK_USE_WIDE8))
 			ctrl |= SDHCI_CTRL_8BITBUS;
 			ctrl |= SDHCI_CTRL_8BITBUS;
 	} else {
 	} else {
-		if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300)
+		if ((SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) ||
+				(host->quirks & SDHCI_QUIRK_USE_WIDE8))
 			ctrl &= ~SDHCI_CTRL_8BITBUS;
 			ctrl &= ~SDHCI_CTRL_8BITBUS;
 		if (mmc->bus_width == 4)
 		if (mmc->bus_width == 4)
 			ctrl |= SDHCI_CTRL_4BITBUS;
 			ctrl |= SDHCI_CTRL_4BITBUS;