[MMC] sdhci: quirk for broken reset

Some controllers fail to complete a reset unless you touch the clock register
first.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 27 insertions, 2 deletions

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index e192f3c9a437..7994c0b70f15 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -32,9 +32,21 @@ static unsigned int debug_nodma = 0;
 static unsigned int debug_forcedma = 0;
 static unsigned int debug_quirks = 0;
 
+#define SDHCI_QUIRK_CLOCK_BEFORE_RESET                  (1<<0)
+
 static const struct pci_device_id pci_ids[] __devinitdata = {
-        /* handle any SD host controller */
-        {PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)},
+        {
+                .vendor         = PCI_VENDOR_ID_RICOH,
+                .device         = PCI_DEVICE_ID_RICOH_R5C822,
+                .subvendor      = PCI_VENDOR_ID_IBM,
+                .subdevice      = PCI_ANY_ID,
+                .driver_data    = SDHCI_QUIRK_CLOCK_BEFORE_RESET,
+        },
+
+        {       /* Generic SD host controller */
+                PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)
+        },
+
         { /* end: all zeroes */ },
 };
 
@@ -808,6 +820,19 @@ static void sdhci_tasklet_finish(unsigned long param)
         if ((mrq->cmd->error != MMC_ERR_NONE) ||
                 (mrq->data && ((mrq->data->error != MMC_ERR_NONE) ||
                 (mrq->data->stop && (mrq->data->stop->error != MMC_ERR_NONE))))) {
+
+                /* Some controllers need this kick or reset won't work here */
+                if (host->chip->quirks & SDHCI_QUIRK_CLOCK_BEFORE_RESET) {
+                        unsigned int clock;
+
+                        /* This is to force an update */
+                        clock = host->clock;
+                        host->clock = 0;
+                        sdhci_set_clock(host, clock);
+                }
+
+                /* Spec says we should do both at the same time, but Ricoh
+                   controllers do not like that. */
                 sdhci_reset(host, SDHCI_RESET_CMD);
                 sdhci_reset(host, SDHCI_RESET_DATA);
         }