diff options
| -rw-r--r-- | Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt | 2 | ||||
| -rw-r--r-- | drivers/scsi/ufs/ufs-qcom.c | 36 | ||||
| -rw-r--r-- | drivers/scsi/ufs/ufs-qcom.h | 4 |
3 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt index a74720486ee2..d78ef63935f9 100644 --- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt +++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt @@ -54,6 +54,8 @@ Optional properties: PHY reset from the UFS controller. - resets : reset node register - reset-names : describe reset node register, the "rst" corresponds to reset the whole UFS IP. +- reset-gpios : A phandle and gpio specifier denoting the GPIO connected + to the RESET pin of the UFS memory device. Note: If above properties are not defined it can be assumed that the supply regulators or clocks are always on. diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c index 02cdcefb81ac..a5b71487a206 100644 --- a/drivers/scsi/ufs/ufs-qcom.c +++ b/drivers/scsi/ufs/ufs-qcom.c @@ -8,6 +8,7 @@ #include <linux/of.h> #include <linux/platform_device.h> #include <linux/phy/phy.h> +#include <linux/gpio/consumer.h> #include <linux/reset-controller.h> #include "ufshcd.h" @@ -1137,6 +1138,15 @@ static int ufs_qcom_init(struct ufs_hba *hba) } } + host->device_reset = devm_gpiod_get_optional(dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(host->device_reset)) { + err = PTR_ERR(host->device_reset); + if (err != -EPROBE_DEFER) + dev_err(dev, "failed to acquire reset gpio: %d\n", err); + goto out_variant_clear; + } + err = ufs_qcom_bus_register(host); if (err) goto out_variant_clear; @@ -1543,6 +1553,31 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba) } /** + * ufs_qcom_device_reset() - toggle the (optional) device reset line + * @hba: per-adapter instance + * + * Toggles the (optional) reset line to reset the attached device. + */ +static void ufs_qcom_device_reset(struct ufs_hba *hba) +{ + struct ufs_qcom_host *host = ufshcd_get_variant(hba); + + /* reset gpio is optional */ + if (!host->device_reset) + return; + + /* + * The UFS device shall detect reset pulses of 1us, sleep for 10us to + * be on the safe side. + */ + gpiod_set_value_cansleep(host->device_reset, 1); + usleep_range(10, 15); + + gpiod_set_value_cansleep(host->device_reset, 0); + usleep_range(10, 15); +} + +/** * struct ufs_hba_qcom_vops - UFS QCOM specific variant operations * * The variant operations configure the necessary controller and PHY @@ -1562,6 +1597,7 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = { .suspend = ufs_qcom_suspend, .resume = ufs_qcom_resume, .dbg_register_dump = ufs_qcom_dump_dbg_regs, + .device_reset = ufs_qcom_device_reset, }; /** diff --git a/drivers/scsi/ufs/ufs-qcom.h b/drivers/scsi/ufs/ufs-qcom.h index 001915d1e0e4..d401f174bb70 100644 --- a/drivers/scsi/ufs/ufs-qcom.h +++ b/drivers/scsi/ufs/ufs-qcom.h @@ -195,6 +195,8 @@ struct ufs_qcom_testbus { u8 select_minor; }; +struct gpio_desc; + struct ufs_qcom_host { /* * Set this capability if host controller supports the QUniPro mode @@ -232,6 +234,8 @@ struct ufs_qcom_host { struct ufs_qcom_testbus testbus; struct reset_controller_dev rcdev; + + struct gpio_desc *device_reset; }; static inline u32 |