[PATCH 5.1 002/121] mmc: sdhci: sdhci-pci-o2micro: Correctly set bus width when tuning

From: Greg Kroah-Hartman
Date: Mon Jun 24 2019 - 06:08:18 EST


From: Raul E Rangel <rrangel@xxxxxxxxxxxx>

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@xxxxxxxxxxxx>
Fixes: 0086fc217d5d7 ("mmc: sdhci: Add support for O2 hardware tuning")
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/host/sdhci-pci-o2micro.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- 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(struc
*/
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(struc

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;