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Subject[PATCH 19/21] [MMC] Quirk for broken reset
Date
Some controllers fail to complete a reset unless you touch the clock
register first.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
---
drivers/mmc/sdhci.c | 29 +++++++++++++++++++++++++++--
1 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 1a12427..617a588 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(unsigne
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);
}
-
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