diff options
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/quirks.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 02145e9697a..1196f61a4ab 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2758,6 +2758,29 @@ static void ricoh_mmc_fixup_r5c832(struct pci_dev *dev) dev_notice(&dev->dev, "proprietary Ricoh MMC controller disabled (via firewire function)\n"); dev_notice(&dev->dev, "MMC cards are now supported by standard SDHCI controller\n"); + + /* + * RICOH 0xe823 SD/MMC card reader fails to recognize + * certain types of SD/MMC cards. Lowering the SD base + * clock frequency from 200Mhz to 50Mhz fixes this issue. + * + * 0x150 - SD2.0 mode enable for changing base clock + * frequency to 50Mhz + * 0xe1 - Base clock frequency + * 0x32 - 50Mhz new clock frequency + * 0xf9 - Key register for 0x150 + * 0xfc - key register for 0xe1 + */ + if (dev->device == PCI_DEVICE_ID_RICOH_R5CE823) { + pci_write_config_byte(dev, 0xf9, 0xfc); + pci_write_config_byte(dev, 0x150, 0x10); + pci_write_config_byte(dev, 0xf9, 0x00); + pci_write_config_byte(dev, 0xfc, 0x01); + pci_write_config_byte(dev, 0xe1, 0x32); + pci_write_config_byte(dev, 0xfc, 0x00); + + dev_notice(&dev->dev, "MMC controller base frequency changed to 50Mhz.\n"); + } } DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_RICOH, PCI_DEVICE_ID_RICOH_R5C832, ricoh_mmc_fixup_r5c832); DECLARE_PCI_FIXUP_RESUME_EARLY(PCI_VENDOR_ID_RICOH, PCI_DEVICE_ID_RICOH_R5C832, ricoh_mmc_fixup_r5c832); |