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path: root/drivers/mmc/host/sdhci-msm.c
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Diffstat (limited to 'drivers/mmc/host/sdhci-msm.c')
-rw-r--r--drivers/mmc/host/sdhci-msm.c42
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index 50c71e0ba5e4..ff9f5b63c337 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -17,6 +17,7 @@
#include <linux/regulator/consumer.h>
#include <linux/interconnect.h>
#include <linux/pinctrl/consumer.h>
+#include <linux/reset.h>
#include "sdhci-pltfm.h"
#include "cqhci.h"
@@ -2482,6 +2483,43 @@ static inline void sdhci_msm_get_of_property(struct platform_device *pdev,
of_property_read_u32(node, "qcom,dll-config", &msm_host->dll_config);
}
+static int sdhci_msm_gcc_reset(struct device *dev, struct sdhci_host *host)
+{
+ struct reset_control *reset;
+ int ret = 0;
+
+ reset = reset_control_get_optional_exclusive(dev, NULL);
+ if (IS_ERR(reset))
+ return dev_err_probe(dev, PTR_ERR(reset),
+ "unable to acquire core_reset\n");
+
+ if (!reset)
+ return ret;
+
+ ret = reset_control_assert(reset);
+ if (ret) {
+ reset_control_put(reset);
+ return dev_err_probe(dev, ret, "core_reset assert failed\n");
+ }
+
+ /*
+ * The hardware requirement for delay between assert/deassert
+ * is at least 3-4 sleep clock (32.7KHz) cycles, which comes to
+ * ~125us (4/32768). To be on the safe side add 200us delay.
+ */
+ usleep_range(200, 210);
+
+ ret = reset_control_deassert(reset);
+ if (ret) {
+ reset_control_put(reset);
+ return dev_err_probe(dev, ret, "core_reset deassert failed\n");
+ }
+
+ usleep_range(200, 210);
+ reset_control_put(reset);
+
+ return ret;
+}
static int sdhci_msm_probe(struct platform_device *pdev)
{
@@ -2529,6 +2567,10 @@ static int sdhci_msm_probe(struct platform_device *pdev)
msm_host->saved_tuning_phase = INVALID_TUNING_PHASE;
+ ret = sdhci_msm_gcc_reset(&pdev->dev, host);
+ if (ret)
+ goto pltfm_free;
+
/* Setup SDCC bus voter clock. */
msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus");
if (!IS_ERR(msm_host->bus_clk)) {