[PATCH 5.12 043/384] mmc: sdhci-pci: Fix initialization of some SD cards for Intel BYT-based controllers

From: Greg Kroah-Hartman
Date: Mon May 10 2021 - 08:05:28 EST


From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

commit 2970134b927834e9249659a70aac48e62dff804a upstream.

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
Link: https://lore.kernel.org/r/20210331081752.23621-1-adrian.hunter@xxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-pci-core.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

--- 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 @@ out:
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 sd
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 sdhc
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;
}