mmc: sdhci: sdhci-pci-o2micro: Correctly set bus width when tuning

commit 0f7b79a44e7d7dd3ef1f59758c1a341f217ff5e5 upstream.

The O2Micro controller only supports tuning at 4-bits. So the host driver
needs to change the bus width while tuning and then set it back when done.

There was a bug in the original implementation in that mmc->ios.bus_width
also wasn't updated. Thus setting the incorrect blocksize in
sdhci_send_tuning which results in a tuning failure.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Fixes: 0086fc217d5d7 ("mmc: sdhci: Add support for O2 hardware tuning")
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c
index 05a012a694b2c6875a6189e5452b55af07fca04d..423c3339c03bc67bb6f6e3aeda29540c63519cdc 100644 (file)
--- a/drivers/mmc/host/sdhci-pci-o2micro.c
+++ b/drivers/mmc/host/sdhci-pci-o2micro.c
@@ -124,6 +124,7 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
         */
        if (mmc->ios.bus_width == MMC_BUS_WIDTH_8) {
                current_bus_width = mmc->ios.bus_width;
+               mmc->ios.bus_width = MMC_BUS_WIDTH_4;
                sdhci_set_bus_width(host, MMC_BUS_WIDTH_4);
        }
 
@@ -135,8 +136,10 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
 
        sdhci_end_tuning(host);
 
-       if (current_bus_width == MMC_BUS_WIDTH_8)
+       if (current_bus_width == MMC_BUS_WIDTH_8) {
+               mmc->ios.bus_width = MMC_BUS_WIDTH_8;
                sdhci_set_bus_width(host, current_bus_width);
+       }
 
        host->flags &= ~SDHCI_HS400_TUNING;
        return 0;