scsi: ufs: sysfs: attribute group for existing sysfs entries.

This patch introduces attribute group to show existing sysfs entries.

Signed-off-by: Stanislav Nijnikov <stanislav.nijnikov@wdc.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 156 insertions, 0 deletions

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
new file mode 100644
index 000000000000..77624d0adee6
--- /dev/null
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Western Digital Corporation
+
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ufs-sysfs.h"
+
+static const char *ufschd_uic_link_state_to_string(
+			enum uic_link_state state)
+{
+	switch (state) {
+	case UIC_LINK_OFF_STATE:	return "OFF";
+	case UIC_LINK_ACTIVE_STATE:	return "ACTIVE";
+	case UIC_LINK_HIBERN8_STATE:	return "HIBERN8";
+	default:			return "UNKNOWN";
+	}
+}
+
+static const char *ufschd_ufs_dev_pwr_mode_to_string(
+			enum ufs_dev_pwr_mode state)
+{
+	switch (state) {
+	case UFS_ACTIVE_PWR_MODE:	return "ACTIVE";
+	case UFS_SLEEP_PWR_MODE:	return "SLEEP";
+	case UFS_POWERDOWN_PWR_MODE:	return "POWERDOWN";
+	default:			return "UNKNOWN";
+	}
+}
+
+static inline ssize_t ufs_sysfs_pm_lvl_store(struct device *dev,
+					     struct device_attribute *attr,
+					     const char *buf, size_t count,
+					     bool rpm)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	unsigned long flags, value;
+
+	if (kstrtoul(buf, 0, &value))
+		return -EINVAL;
+
+	if (value >= UFS_PM_LVL_MAX)
+		return -EINVAL;
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	if (rpm)
+		hba->rpm_lvl = value;
+	else
+		hba->spm_lvl = value;
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+	return count;
+}
+
+static ssize_t rpm_lvl_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	int curr_len;
+	u8 lvl;
+
+	curr_len = snprintf(buf, PAGE_SIZE,
+			    "\nCurrent Runtime PM level [%d] => dev_state [%s] link_state [%s]\n",
+			    hba->rpm_lvl,
+			    ufschd_ufs_dev_pwr_mode_to_string(
+				ufs_pm_lvl_states[hba->rpm_lvl].dev_state),
+			    ufschd_uic_link_state_to_string(
+				ufs_pm_lvl_states[hba->rpm_lvl].link_state));
+
+	curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+			     "\nAll available Runtime PM levels info:\n");
+	for (lvl = UFS_PM_LVL_0; lvl < UFS_PM_LVL_MAX; lvl++)
+		curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+				     "\tRuntime PM level [%d] => dev_state [%s] link_state [%s]\n",
+				    lvl,
+				    ufschd_ufs_dev_pwr_mode_to_string(
+					ufs_pm_lvl_states[lvl].dev_state),
+				    ufschd_uic_link_state_to_string(
+					ufs_pm_lvl_states[lvl].link_state));
+
+	return curr_len;
+}
+
+static ssize_t rpm_lvl_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	return ufs_sysfs_pm_lvl_store(dev, attr, buf, count, true);
+}
+
+static ssize_t spm_lvl_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	int curr_len;
+	u8 lvl;
+
+	curr_len = snprintf(buf, PAGE_SIZE,
+			    "\nCurrent System PM level [%d] => dev_state [%s] link_state [%s]\n",
+			    hba->spm_lvl,
+			    ufschd_ufs_dev_pwr_mode_to_string(
+				ufs_pm_lvl_states[hba->spm_lvl].dev_state),
+			    ufschd_uic_link_state_to_string(
+				ufs_pm_lvl_states[hba->spm_lvl].link_state));
+
+	curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+			     "\nAll available System PM levels info:\n");
+	for (lvl = UFS_PM_LVL_0; lvl < UFS_PM_LVL_MAX; lvl++)
+		curr_len += snprintf((buf + curr_len), (PAGE_SIZE - curr_len),
+				     "\tSystem PM level [%d] => dev_state [%s] link_state [%s]\n",
+				    lvl,
+				    ufschd_ufs_dev_pwr_mode_to_string(
+					ufs_pm_lvl_states[lvl].dev_state),
+				    ufschd_uic_link_state_to_string(
+					ufs_pm_lvl_states[lvl].link_state));
+
+	return curr_len;
+}
+
+static ssize_t spm_lvl_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	return ufs_sysfs_pm_lvl_store(dev, attr, buf, count, false);
+}
+
+static DEVICE_ATTR_RW(rpm_lvl);
+static DEVICE_ATTR_RW(spm_lvl);
+
+static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
+	&dev_attr_rpm_lvl.attr,
+	&dev_attr_spm_lvl.attr,
+	NULL
+};
+
+static const struct attribute_group ufs_sysfs_default_group = {
+	.attrs = ufs_sysfs_ufshcd_attrs,
+};
+
+static const struct attribute_group *ufs_sysfs_groups[] = {
+	&ufs_sysfs_default_group,
+	NULL,
+};
+
+void ufs_sysfs_add_nodes(struct device *dev)
+{
+	int ret;
+
+	ret = sysfs_create_groups(&dev->kobj, ufs_sysfs_groups);
+	if (ret)
+		dev_err(dev,
+			"%s: sysfs groups creation failed (err = %d)\n",
+			__func__, ret);
+}
+
+void ufs_sysfs_remove_nodes(struct device *dev)
+{
+	sysfs_remove_groups(&dev->kobj, ufs_sysfs_groups);
+}