scsi: ufs: sysfs: reworking of the rpm_lvl and spm_lvl entries

Read from these files will return the integer value of the chosen power
management level now. Separate entries were added to show the target UFS
device and UIC link states. The description of the possible power
managements levels was added to the ABI file. The on-write behaviour of
these entries wasn't changed.

[mkp: typo]

Signed-off-by: Stanislav Nijnikov <stanislav.nijnikov@wdc.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Documentation/ABI/testing/sysfs-driver-ufs

@@ -802,3 +802,70 @@ Description:	This file shows the The amount of physical memory needed
 		the particular logical unit. The full information about
 		the attribute could be found at UFS specifications 2.1.
 		The file is read only.
+
+
+What:		/sys/bus/platform/drivers/ufshcd/*/rpm_lvl
+Date:		September 2014
+Contact:	Subhash Jadavani <subhashj@codeaurora.org>
+Description:	This entry could be used to set or show the UFS device
+		runtime power management level. The current driver
+		implementation supports 6 levels with next target states:
+		0 - an UFS device will stay active, an UIC link will
+		stay active
+		1 - an UFS device will stay active, an UIC link will
+		hibernate
+		2 - an UFS device will moved to sleep, an UIC link will
+		stay active
+		3 - an UFS device will moved to sleep, an UIC link will
+		hibernate
+		4 - an UFS device will be powered off, an UIC link will
+		hibernate
+		5 - an UFS device will be powered off, an UIC link will
+		be powered off
+
+What:		/sys/bus/platform/drivers/ufshcd/*/rpm_target_dev_state
+Date:		February 2018
+Contact:	Subhash Jadavani <subhashj@codeaurora.org>
+Description:	This entry shows the target power mode of an UFS device
+		for the chosen runtime power management level.
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/rpm_target_link_state
+Date:		February 2018
+Contact:	Subhash Jadavani <subhashj@codeaurora.org>
+Description:	This entry shows the target state of an UFS UIC link
+		for the chosen runtime power management level.
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/spm_lvl
+Date:		September 2014
+Contact:	Subhash Jadavani <subhashj@codeaurora.org>
+Description:	This entry could be used to set or show the UFS device
+		system power management level. The current driver
+		implementation supports 6 levels with next target states:
+		0 - an UFS device will stay active, an UIC link will
+		stay active
+		1 - an UFS device will stay active, an UIC link will
+		hibernate
+		2 - an UFS device will moved to sleep, an UIC link will
+		stay active
+		3 - an UFS device will moved to sleep, an UIC link will
+		hibernate
+		4 - an UFS device will be powered off, an UIC link will
+		hibernate
+		5 - an UFS device will be powered off, an UIC link will
+		be powered off
+
+What:		/sys/bus/platform/drivers/ufshcd/*/spm_target_dev_state
+Date:		February 2018
+Contact:	Subhash Jadavani <subhashj@codeaurora.org>
+Description:	This entry shows the target power mode of an UFS device
+		for the chosen system power management level.
+		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/spm_target_link_state
+Date:		February 2018
+Contact:	Subhash Jadavani <subhashj@codeaurora.org>
+Description:	This entry shows the target state of an UFS UIC link
+		for the chosen system power management level.
+		The file is read only.

drivers/scsi/ufs/ufs-sysfs.c

@@ -57,29 +57,8 @@ 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;
+
+	return sprintf(buf, "%d\n", hba->rpm_lvl);
 }
 
 static ssize_t rpm_lvl_store(struct device *dev,
@@ -88,33 +67,30 @@ static ssize_t rpm_lvl_store(struct device *dev,
 	return ufs_sysfs_pm_lvl_store(dev, attr, buf, count, true);
 }
 
+static ssize_t rpm_target_dev_state_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", ufschd_ufs_dev_pwr_mode_to_string(
+			ufs_pm_lvl_states[hba->rpm_lvl].dev_state));
+}
+
+static ssize_t rpm_target_link_state_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", ufschd_uic_link_state_to_string(
+			ufs_pm_lvl_states[hba->rpm_lvl].link_state));
+}
+
 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;
+	return sprintf(buf, "%d\n", hba->spm_lvl);
 }
 
 static ssize_t spm_lvl_store(struct device *dev,
@@ -123,12 +99,38 @@ static ssize_t spm_lvl_store(struct device *dev,
 	return ufs_sysfs_pm_lvl_store(dev, attr, buf, count, false);
 }
 
+static ssize_t spm_target_dev_state_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", ufschd_ufs_dev_pwr_mode_to_string(
+				ufs_pm_lvl_states[hba->spm_lvl].dev_state));
+}
+
+static ssize_t spm_target_link_state_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", ufschd_uic_link_state_to_string(
+				ufs_pm_lvl_states[hba->spm_lvl].link_state));
+}
+
 static DEVICE_ATTR_RW(rpm_lvl);
+static DEVICE_ATTR_RO(rpm_target_dev_state);
+static DEVICE_ATTR_RO(rpm_target_link_state);
 static DEVICE_ATTR_RW(spm_lvl);
+static DEVICE_ATTR_RO(spm_target_dev_state);
+static DEVICE_ATTR_RO(spm_target_link_state);
 
 static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
 	&dev_attr_rpm_lvl.attr,
+	&dev_attr_rpm_target_dev_state.attr,
+	&dev_attr_rpm_target_link_state.attr,
 	&dev_attr_spm_lvl.attr,
+	&dev_attr_spm_target_dev_state.attr,
+	&dev_attr_spm_target_link_state.attr,
 	NULL
 };