mmc: sdhci-pci-gli: Enable short circuit protection mechanism of GL9755

Short circuit protection mechanism of GL9755 is disabled by HW default
setting. Enable short circuit protection to prevent GL9755 from being
damaged by short circuit or over current.

Signed-off-by: Renius Chen <reniuschengl@gmail.com>
Link: https://lore.kernel.org/r/20210225111307.62975-1-reniuschengl@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
index 4a0f69b97a78f86bd302430d46c014d25986b166..fd0939355584adff896c6f31ac7488f00934e9e1 100644 (file)
--- a/drivers/mmc/host/sdhci-pci-gli.c
+++ b/drivers/mmc/host/sdhci-pci-gli.c
@@ -123,6 +123,9 @@
 #define PCI_GLI_9755_PLLSSC        0x68
 #define   PCI_GLI_9755_PLLSSC_PPM    GENMASK(15, 0)
 
+#define PCI_GLI_9755_SerDes  0x70
+#define PCI_GLI_9755_SCP_DIS   BIT(19)
+
 #define GLI_MAX_TUNING_LOOP 40
 
 /* Genesys Logic chipset */
@@ -547,6 +550,11 @@ static void gl9755_hw_setting(struct sdhci_pci_slot *slot)
        value &= ~PCI_GLI_9755_DMACLK;
        pci_write_config_dword(pdev, PCI_GLI_9755_PECONF, value);
 
+       /* enable short circuit protection */
+       pci_read_config_dword(pdev, PCI_GLI_9755_SerDes, &value);
+       value &= ~PCI_GLI_9755_SCP_DIS;
+       pci_write_config_dword(pdev, PCI_GLI_9755_SerDes, value);
+
        gl9755_wt_off(pdev);
 }