From: Darren Salt mmc: Power quirk for ENE controllers Support for these devices was broken for 2.6.18-rc1 and later by commit 146ad66eac836c0b976c98f428d73e1f6a75270d, which added voltage level support. This restores the previous behaviour for these devices by ensuring that when the voltage is changed, only one write to set the voltage is performed. It may be that both writes are needed if the voltage is being changed between two non-zero values or that it's safe to ensure that only one write is done if the hardware only supports one voltage; I don't know whether either is the case nor can I test since I have only the one SD reader (1524:0550), and it supports just the one voltage. Signed-off-by: Darren Salt Signed-off-by: Pierre Ossman Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/sdhci.c | 22 +++++++++++++++++++--- include/linux/pci_ids.h | 1 + 2 files changed, 20 insertions(+), 3 deletions(-) --- linux-2.6.20.1.orig/drivers/mmc/sdhci.c +++ linux-2.6.20.1/drivers/mmc/sdhci.c @@ -37,6 +37,7 @@ static unsigned int debug_quirks = 0; #define SDHCI_QUIRK_FORCE_DMA (1<<1) /* Controller doesn't like some resets when there is no card inserted. */ #define SDHCI_QUIRK_NO_CARD_NO_RESET (1<<2) +#define SDHCI_QUIRK_SINGLE_POWER_WRITE (1<<3) static const struct pci_device_id pci_ids[] __devinitdata = { { @@ -65,6 +66,14 @@ static const struct pci_device_id pci_id .driver_data = SDHCI_QUIRK_FORCE_DMA, }, + { + .vendor = PCI_VENDOR_ID_ENE, + .device = PCI_DEVICE_ID_ENE_CB712_SD, + .subvendor = PCI_ANY_ID, + .subdevice = PCI_ANY_ID, + .driver_data = SDHCI_QUIRK_SINGLE_POWER_WRITE, + }, + { /* Generic SD host controller */ PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00) }, @@ -674,10 +683,17 @@ static void sdhci_set_power(struct sdhci if (host->power == power) return; - writeb(0, host->ioaddr + SDHCI_POWER_CONTROL); - - if (power == (unsigned short)-1) + if (power == (unsigned short)-1) { + writeb(0, host->ioaddr + SDHCI_POWER_CONTROL); goto out; + } + + /* + * Spec says that we should clear the power reg before setting + * a new value. Some controllers don't seem to like this though. + */ + if (!(host->chip->quirks & SDHCI_QUIRK_SINGLE_POWER_WRITE)) + writeb(0, host->ioaddr + SDHCI_POWER_CONTROL); pwr = SDHCI_POWER_ON; --- linux-2.6.20.1.orig/include/linux/pci_ids.h +++ linux-2.6.20.1/include/linux/pci_ids.h @@ -1971,6 +1971,7 @@ #define PCI_DEVICE_ID_TOPIC_TP560 0x0000 #define PCI_VENDOR_ID_ENE 0x1524 +#define PCI_DEVICE_ID_ENE_CB712_SD 0x0550 #define PCI_DEVICE_ID_ENE_1211 0x1211 #define PCI_DEVICE_ID_ENE_1225 0x1225 #define PCI_DEVICE_ID_ENE_1410 0x1410 -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/