Bus power may control card power, but the full reset done by SDHCI at
initialization still may not reset the power, whereas a direct write to
SDHCI_POWER_CONTROL can. That might be needed to initialize correctly, if
the card was left powered on previously.
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/mmc/host/sdhci-pci-core.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index b3caa174effe..be19785227fe 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -516,6 +516,7 @@ struct intel_host {
int drv_strength;
bool d3_retune;
bool rpm_retune_ok;
+ bool needs_pwr_off;
u32 glk_rx_ctrl1;
u32 glk_tun_val;
u32 active_ltr;
@@ -643,9 +644,25 @@ static int bxt_get_cd(struct mmc_host *mmc)
static void sdhci_intel_set_power(struct sdhci_host *host, unsigned char mode,
unsigned short vdd)
{
+ struct sdhci_pci_slot *slot = sdhci_priv(host);
+ struct intel_host *intel_host = sdhci_pci_priv(slot);
int cntr;
u8 reg;
+ /*
+ * Bus power may control card power, but a full reset still may not
+ * reset the power, whereas a direct write to SDHCI_POWER_CONTROL can.
+ * That might be needed to initialize correctly, if the card was left
+ * powered on previously.
+ */
+ if (intel_host->needs_pwr_off) {
+ intel_host->needs_pwr_off = false;
+ if (mode != MMC_POWER_OFF) {
+ sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+ usleep_range(10000, 12500);
+ }
+ }
+
sdhci_set_power(host, mode, vdd);
if (mode == MMC_POWER_OFF)
@@ -1135,6 +1152,14 @@ static int byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
return 0;
}
+static void byt_needs_pwr_off(struct sdhci_pci_slot *slot)
+{
+ struct intel_host *intel_host = sdhci_pci_priv(slot);
+ u8 reg = sdhci_readb(slot->host, SDHCI_POWER_CONTROL);
+
+ intel_host->needs_pwr_off = reg & SDHCI_POWER_ON;
+}
+
static int byt_sd_probe_slot(struct sdhci_pci_slot *slot)
{
byt_probe_slot(slot);
@@ -1152,6 +1177,8 @@ static int byt_sd_probe_slot(struct sdhci_pci_slot *slot)
slot->chip->pdev->subsystem_device == PCI_SUBDEVICE_ID_NI_78E3)
slot->host->mmc->caps2 |= MMC_CAP2_AVOID_3_3V;
+ byt_needs_pwr_off(slot);
+
return 0;
}
--
2.17.1
