1 files changed, 83 insertions, 2 deletions

diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-sysfs.c
index 0a088b47d557..53aea56d1de1 100644
--- a/drivers/ufs/core/ufs-sysfs.c
+++ b/drivers/ufs/core/ufs-sysfs.c
@@ -225,12 +225,13 @@ static ssize_t wb_on_store(struct device *dev, struct device_attribute *attr,
 	unsigned int wb_enable;
 	ssize_t res;
 
-	if (!ufshcd_is_wb_allowed(hba) || ufshcd_is_clkscaling_supported(hba)) {
+	if (!ufshcd_is_wb_allowed(hba) || (ufshcd_is_clkscaling_supported(hba)
+		&& ufshcd_enable_wb_if_scaling_up(hba))) {
 		/*
 		 * If the platform supports UFSHCD_CAP_CLK_SCALING, turn WB
 		 * on/off will be done while clock scaling up/down.
 		 */
-		dev_warn(dev, "To control WB through wb_on is not allowed!\n");
+		dev_warn(dev, "It is not allowed to configure WB!\n");
 		return -EOPNOTSUPP;
 	}
 
@@ -254,6 +255,49 @@ out:
 	return res < 0 ? res : count;
 }
 
+static ssize_t enable_wb_buf_flush_show(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%d\n", hba->dev_info.wb_buf_flush_enabled);
+}
+
+static ssize_t enable_wb_buf_flush_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	unsigned int enable_wb_buf_flush;
+	ssize_t res;
+
+	if (!ufshcd_is_wb_buf_flush_allowed(hba)) {
+		dev_warn(dev, "It is not allowed to configure WB buf flushing!\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (kstrtouint(buf, 0, &enable_wb_buf_flush))
+		return -EINVAL;
+
+	if (enable_wb_buf_flush != 0 && enable_wb_buf_flush != 1)
+		return -EINVAL;
+
+	down(&hba->host_sem);
+	if (!ufshcd_is_user_access_allowed(hba)) {
+		res = -EBUSY;
+		goto out;
+	}
+
+	ufshcd_rpm_get_sync(hba);
+	res = ufshcd_wb_toggle_buf_flush(hba, enable_wb_buf_flush);
+	ufshcd_rpm_put_sync(hba);
+
+out:
+	up(&hba->host_sem);
+	return res < 0 ? res : count;
+}
+
 static DEVICE_ATTR_RW(rpm_lvl);
 static DEVICE_ATTR_RO(rpm_target_dev_state);
 static DEVICE_ATTR_RO(rpm_target_link_state);
@@ -262,6 +306,7 @@ static DEVICE_ATTR_RO(spm_target_dev_state);
 static DEVICE_ATTR_RO(spm_target_link_state);
 static DEVICE_ATTR_RW(auto_hibern8);
 static DEVICE_ATTR_RW(wb_on);
+static DEVICE_ATTR_RW(enable_wb_buf_flush);
 
 static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
 	&dev_attr_rpm_lvl.attr,
@@ -272,6 +317,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
 	&dev_attr_spm_target_link_state.attr,
 	&dev_attr_auto_hibern8.attr,
 	&dev_attr_wb_on.attr,
+	&dev_attr_enable_wb_buf_flush.attr,
 	NULL
 };
 
@@ -279,6 +325,40 @@ static const struct attribute_group ufs_sysfs_default_group = {
 	.attrs = ufs_sysfs_ufshcd_attrs,
 };
 
+static ssize_t clock_scaling_show(struct device *dev, struct device_attribute *attr,
+				  char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%d\n", ufshcd_is_clkscaling_supported(hba));
+}
+
+static ssize_t write_booster_show(struct device *dev, struct device_attribute *attr,
+				  char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%d\n", ufshcd_is_wb_allowed(hba));
+}
+
+static DEVICE_ATTR_RO(clock_scaling);
+static DEVICE_ATTR_RO(write_booster);
+
+/*
+ * See Documentation/ABI/testing/sysfs-driver-ufs for the semantics of this
+ * group.
+ */
+static struct attribute *ufs_sysfs_capabilities_attrs[] = {
+	&dev_attr_clock_scaling.attr,
+	&dev_attr_write_booster.attr,
+	NULL
+};
+
+static const struct attribute_group ufs_sysfs_capabilities_group = {
+	.name = "capabilities",
+	.attrs = ufs_sysfs_capabilities_attrs,
+};
+
 static ssize_t monitor_enable_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
@@ -1134,6 +1214,7 @@ static const struct attribute_group ufs_sysfs_attributes_group = {
 
 static const struct attribute_group *ufs_sysfs_groups[] = {
 	&ufs_sysfs_default_group,
+	&ufs_sysfs_capabilities_group,
 	&ufs_sysfs_monitor_group,
 	&ufs_sysfs_device_descriptor_group,
 	&ufs_sysfs_interconnect_descriptor_group,