[MMC] sdhci: quirk for broken reset
authorPierre Ossman <drzeus@drzeus.cx>
Fri, 30 Jun 2006 09:22:33 +0000 (02:22 -0700)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Sun, 2 Jul 2006 17:02:00 +0000 (18:02 +0100)
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>
drivers/mmc/sdhci.c

index e192f3c9a43789f0a82ce348f945e513bc2df3a2..7994c0b70f1576d85ed0358ffdea69e4d07bb685 100644 (file)
@@ -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);
        }