diff options
Diffstat (limited to 'drivers/mmc/host')
| -rw-r--r-- | drivers/mmc/host/sdhci-msm.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c index 65661ad07a9d..e395411fb6fd 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" @@ -2507,6 +2508,43 @@ 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) { @@ -2554,6 +2592,10 @@ 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)) { |