This device reports SDHCI_CLOCK_INT_STABLE even though it's not ready to take SDHCI_CLOCK_CARD_EN. The symptom is that reading SDHCI_CLOCK_CONTROL after enabling the clock shows absence of the bit from the register (e.g. expecting 0x0000fa07 = 0x0000fa03 | SDHCI_CLOCK_CARD_EN but only observed the first operand). mmc1: Timeout waiting for hardware cmd interrupt. mmc1: sdhci: ============ SDHCI REGISTER DUMP =========== mmc1: sdhci: Sys addr: 0x00000000 | Version: 0x00000603 mmc1: sdhci: Blk size: 0x00000000 | Blk cnt: 0x00000000 mmc1: sdhci: Argument: 0x00000000 | Trn mode: 0x00000000 mmc1: sdhci: Present: 0x01ff0001 | Host ctl: 0x00000001 mmc1: sdhci: Power: 0x0000000f | Blk gap: 0x00000000 mmc1: sdhci: Wake-up: 0x00000000 | Clock: 0x0000fa03 mmc1: sdhci: Timeout: 0x00000000 | Int stat: 0x00000000 mmc1: sdhci: Int enab: 0x00ff0083 | Sig enab: 0x00ff0083 mmc1: sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000 mmc1: sdhci: Caps: 0x25fcc8bf | Caps_1: 0x00002077 mmc1: sdhci: Cmd: 0x00000000 | Max curr: 0x005800c8 mmc1: sdhci: Resp[0]: 0x00000000 | Resp[1]: 0x00000000 mmc1: sdhci: Resp[2]: 0x00000000 | Resp[3]: 0x00000000 mmc1: sdhci: Host ctl2: 0x00000008 mmc1: sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x00000000 mmc1: sdhci: ============================================ The problem happens during wakeup from S3. Adding a delay quirk after power up reliably fixes the problem. Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx> --- drivers/mmc/host/sdhci-pci-o2micro.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c index 77e9bc4aaee9..3e5ecf7ce101 100644 --- a/drivers/mmc/host/sdhci-pci-o2micro.c +++ b/drivers/mmc/host/sdhci-pci-o2micro.c @@ -490,6 +490,8 @@ int sdhci_pci_o2_probe(struct sdhci_pci_chip *chip) pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch); break; case PCI_DEVICE_ID_O2_SEABIRD0: + if (chip->pdev->revision == 0x01) + chip->quirks |= SDHCI_QUIRK_DELAY_AFTER_POWER; case PCI_DEVICE_ID_O2_SEABIRD1: /* UnLock WP */ ret = pci_read_config_byte(chip->pdev, -- 2.19.0.444.g18242da7ef-goog