[PATCH 1/5] libata: clean up lpm related symbols and sysfs show/store functions

[Tejun Heo <tj@kernel.org>]

Link power management related symbols are in confusing state w/ mixed
usages of lpm, ipm and pm.  This patch cleans up lpm related symbols
and sysfs show/store functions as follows.

* lpm states - NOT_AVAILABLE, MIN_POWER, MAX_PERFORMANCE and
  MEDIUM_POWER are renamed to ATA_LPM_UNKNOWN and
  ATA_LPM_{MIN|MAX|MED}_POWER.

* Pre/postfixes are unified to lpm.

* sysfs show/store functions for link_power_management_policy were
  curiously named get/put and unnecessarily complex.  Renamed to
  show/store and simplified.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
 drivers/ata/ahci.c          |    2 +-
 drivers/ata/ahci.h          |    2 +-
 drivers/ata/ahci_platform.c |    2 +-
 drivers/ata/libahci.c       |   20 ++++++-------
 drivers/ata/libata-core.c   |   50 ++++++++++++++++----------------
 drivers/ata/libata-eh.c     |    2 +-
 drivers/ata/libata-scsi.c   |   68 ++++++++++++++----------------------------
 drivers/ata/libata.h        |    6 ++-
 include/linux/libata.h      |   29 +++++++++---------
 9 files changed, 80 insertions(+), 101 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 013727b..b4e2730 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1202,7 +1202,7 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 				   0x100 + ap->port_no * 0x80, "port");
 
 		/* set initial link pm policy */
-		ap->pm_policy = NOT_AVAILABLE;
+		ap->lpm_policy = ATA_LPM_UNKNOWN;
 
 		/* set enclosure management message type */
 		if (ap->flags & ATA_FLAG_EM)
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 474427b..f5ba3fa 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -216,7 +216,7 @@ enum {
 	AHCI_FLAG_COMMON		= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
 					  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
 					  ATA_FLAG_ACPI_SATA | ATA_FLAG_AN |
-					  ATA_FLAG_IPM,
+					  ATA_FLAG_LPM,
 
 	ICH_MAP				= 0x90, /* ICH MAP register */
 
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 4e97f33..3581d50 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -126,7 +126,7 @@ static int __init ahci_probe(struct platform_device *pdev)
 		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
 
 		/* set initial link pm policy */
-		ap->pm_policy = NOT_AVAILABLE;
+		ap->lpm_policy = ATA_LPM_UNKNOWN;
 
 		/* set enclosure management message type */
 		if (ap->flags & ATA_FLAG_EM)
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 666850d..7c043a0 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -56,8 +56,7 @@ MODULE_PARM_DESC(skip_host_reset, "skip global host reset (0=don't skip, 1=skip)
 module_param_named(ignore_sss, ahci_ignore_sss, int, 0444);
 MODULE_PARM_DESC(ignore_sss, "Ignore staggered spinup flag (0=don't ignore, 1=ignore)");
 
-static int ahci_enable_alpm(struct ata_port *ap,
-		enum link_pm policy);
+static int ahci_enable_alpm(struct ata_port *ap, enum ata_lpm_policy policy);
 static void ahci_disable_alpm(struct ata_port *ap);
 static ssize_t ahci_led_show(struct ata_port *ap, char *buf);
 static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,
@@ -657,7 +656,7 @@ static void ahci_disable_alpm(struct ata_port *ap)
 	u32 cmd;
 	struct ahci_port_priv *pp = ap->private_data;
 
-	/* IPM bits should be disabled by libata-core */
+	/* LPM bits should be disabled by libata-core */
 	/* get the existing command bits */
 	cmd = readl(port_mmio + PORT_CMD);
 
@@ -699,8 +698,7 @@ static void ahci_disable_alpm(struct ata_port *ap)
 	 */
 }
 
-static int ahci_enable_alpm(struct ata_port *ap,
-	enum link_pm policy)
+static int ahci_enable_alpm(struct ata_port *ap, enum ata_lpm_policy policy)
 {
 	struct ahci_host_priv *hpriv = ap->host->private_data;
 	void __iomem *port_mmio = ahci_port_base(ap);
@@ -713,21 +711,21 @@ static int ahci_enable_alpm(struct ata_port *ap,
 		return -EINVAL;
 
 	switch (policy) {
-	case MAX_PERFORMANCE:
-	case NOT_AVAILABLE:
+	case ATA_LPM_MAX_POWER:
+	case ATA_LPM_UNKNOWN:
 		/*
-		 * if we came here with NOT_AVAILABLE,
+		 * if we came here with ATA_LPM_UNKNOWN,
 		 * it just means this is the first time we
 		 * have tried to enable - default to max performance,
 		 * and let the user go to lower power modes on request.
 		 */
 		ahci_disable_alpm(ap);
 		return 0;
-	case MIN_POWER:
+	case ATA_LPM_MIN_POWER:
 		/* configure HBA to enter SLUMBER */
 		asp = PORT_CMD_ASP;
 		break;
-	case MEDIUM_POWER:
+	case ATA_LPM_MED_POWER:
 		/* configure HBA to enter PARTIAL */
 		asp = 0;
 		break;
@@ -770,7 +768,7 @@ static int ahci_enable_alpm(struct ata_port *ap,
 	writel(cmd, port_mmio + PORT_CMD);
 	cmd = readl(port_mmio + PORT_CMD);
 
-	/* IPM bits should be set by libata-core */
+	/* LPM bits should be set by libata-core */
 	return 0;
 }
 
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 9ceb493..a7274f5 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1030,7 +1030,7 @@ const char *sata_spd_string(unsigned int spd)
 	return spd_str[spd - 1];
 }
 
-static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
+static int ata_dev_set_dipm(struct ata_device *dev, enum ata_lpm_policy policy)
 {
 	struct ata_link *link = dev->link;
 	struct ata_port *ap = link->ap;
@@ -1040,14 +1040,14 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
 
 	/*
 	 * disallow DIPM for drivers which haven't set
-	 * ATA_FLAG_IPM.  This is because when DIPM is enabled,
+	 * ATA_FLAG_LPM.  This is because when DIPM is enabled,
 	 * phy ready will be set in the interrupt status on
 	 * state changes, which will cause some drivers to
 	 * think there are errors - additionally drivers will
 	 * need to disable hot plug.
 	 */
-	if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
-		ap->pm_policy = NOT_AVAILABLE;
+	if (!(ap->flags & ATA_FLAG_LPM) || !ata_dev_enabled(dev)) {
+		ap->lpm_policy = ATA_LPM_UNKNOWN;
 		return -EINVAL;
 	}
 
@@ -1066,8 +1066,8 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
 		return rc;
 
 	switch (policy) {
-	case MIN_POWER:
-		/* no restrictions on IPM transitions */
+	case ATA_LPM_MIN_POWER:
+		/* no restrictions on LPM transitions */
 		scontrol &= ~(0x3 << 8);
 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
 		if (rc)
@@ -1078,8 +1078,8 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
 			err_mask = ata_dev_set_feature(dev,
 					SETFEATURES_SATA_ENABLE, SATA_DIPM);
 		break;
-	case MEDIUM_POWER:
-		/* allow IPM to PARTIAL */
+	case ATA_LPM_MED_POWER:
+		/* allow LPM to PARTIAL */
 		scontrol &= ~(0x1 << 8);
 		scontrol |= (0x2 << 8);
 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
@@ -1087,21 +1087,21 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
 			return rc;
 
 		/*
-		 * we don't have to disable DIPM since IPM flags
+		 * we don't have to disable DIPM since LPM flags
 		 * disallow transitions to SLUMBER, which effectively
 		 * disable DIPM if it does not support PARTIAL
 		 */
 		break;
-	case NOT_AVAILABLE:
-	case MAX_PERFORMANCE:
-		/* disable all IPM transitions */
+	case ATA_LPM_UNKNOWN:
+	case ATA_LPM_MAX_POWER:
+		/* disable all LPM transitions */
 		scontrol |= (0x3 << 8);
 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
 		if (rc)
 			return rc;
 
 		/*
-		 * we don't have to disable DIPM since IPM flags
+		 * we don't have to disable DIPM since LPM flags
 		 * disallow all transitions which effectively
 		 * disable DIPM anyway.
 		 */
@@ -1125,9 +1125,9 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
  *	enabling Host Initiated Power management.
  *
  *	Locking: Caller.
- *	Returns: -EINVAL if IPM is not supported, 0 otherwise.
+ *	Returns: -EINVAL if LPM is not supported, 0 otherwise.
  */
-void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
+void ata_dev_enable_pm(struct ata_device *dev, enum ata_lpm_policy policy)
 {
 	int rc = 0;
 	struct ata_port *ap = dev->link->ap;
@@ -1141,9 +1141,9 @@ void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
 
 enable_pm_out:
 	if (rc)
-		ap->pm_policy = MAX_PERFORMANCE;
+		ap->lpm_policy = ATA_LPM_MAX_POWER;
 	else
-		ap->pm_policy = policy;
+		ap->lpm_policy = policy;
 	return /* rc */;	/* hopefully we can use 'rc' eventually */
 }
 
@@ -1164,15 +1164,15 @@ static void ata_dev_disable_pm(struct ata_device *dev)
 {
 	struct ata_port *ap = dev->link->ap;
 
-	ata_dev_set_dipm(dev, MAX_PERFORMANCE);
+	ata_dev_set_dipm(dev, ATA_LPM_MAX_POWER);
 	if (ap->ops->disable_pm)
 		ap->ops->disable_pm(ap);
 }
 #endif	/* CONFIG_PM */
 
-void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)
+void ata_lpm_schedule(struct ata_port *ap, enum ata_lpm_policy policy)
 {
-	ap->pm_policy = policy;
+	ap->lpm_policy = policy;
 	ap->link.eh_info.action |= ATA_EH_LPM;
 	ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
 	ata_port_schedule_eh(ap);
@@ -1201,7 +1201,7 @@ static void ata_lpm_disable(struct ata_host *host)
 
 	for (i = 0; i < host->n_ports; i++) {
 		struct ata_port *ap = host->ports[i];
-		ata_lpm_schedule(ap, ap->pm_policy);
+		ata_lpm_schedule(ap, ap->lpm_policy);
 	}
 }
 #endif	/* CONFIG_PM */
@@ -2564,7 +2564,7 @@ int ata_dev_configure(struct ata_device *dev)
 	if (dev->flags & ATA_DFLAG_LBA48)
 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
 
-	if (!(dev->horkage & ATA_HORKAGE_IPM)) {
+	if (!(dev->horkage & ATA_HORKAGE_LPM)) {
 		if (ata_id_has_hipm(dev->id))
 			dev->flags |= ATA_DFLAG_HIPM;
 		if (ata_id_has_dipm(dev->id))
@@ -2591,11 +2591,11 @@ int ata_dev_configure(struct ata_device *dev)
 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
 					 dev->max_sectors);
 
-	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
-		dev->horkage |= ATA_HORKAGE_IPM;
+	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_LPM) {
+		dev->horkage |= ATA_HORKAGE_LPM;
 
 		/* reset link pm_policy for this port to no pm */
-		ap->pm_policy = MAX_PERFORMANCE;
+		ap->lpm_policy = ATA_LPM_MAX_POWER;
 	}
 
 	if (ap->ops->dev_config)
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 0108731..ae2f697 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -3566,7 +3566,7 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 		/* configure link power saving */
 		if (ehc->i.action & ATA_EH_LPM)
 			ata_for_each_dev(dev, link, ALL)
-				ata_dev_enable_pm(dev, ap->pm_policy);
+				ata_dev_enable_pm(dev, ap->lpm_policy);
 
 		/* this link is okay now */
 		ehc->i.flags = 0;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index f1c0118..aa56681 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -103,72 +103,50 @@ static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
 	0, 30	/* extended self test time, see 05-359r1 */
 };
 
-static const struct {
-	enum link_pm	value;
-	const char	*name;
-} link_pm_policy[] = {
-	{ NOT_AVAILABLE, "max_performance" },
-	{ MIN_POWER, "min_power" },
-	{ MAX_PERFORMANCE, "max_performance" },
-	{ MEDIUM_POWER, "medium_power" },
+static const char *ata_lpm_policy_names[] = {
+	[ATA_LPM_UNKNOWN]	= "max_performance",
+	[ATA_LPM_MAX_POWER]	= "max_performance",
+	[ATA_LPM_MED_POWER]	= "medium_power",
+	[ATA_LPM_MIN_POWER]	= "min_power",
 };
 
-static const char *ata_scsi_lpm_get(enum link_pm policy)
-{
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++)
-		if (link_pm_policy[i].value == policy)
-			return link_pm_policy[i].name;
-
-	return NULL;
-}
-
-static ssize_t ata_scsi_lpm_put(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf, size_t count)
+static ssize_t ata_scsi_lpm_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
 {
 	struct Scsi_Host *shost = class_to_shost(dev);
 	struct ata_port *ap = ata_shost_to_port(shost);
-	enum link_pm policy = 0;
-	int i;
+	enum ata_lpm_policy policy;
 
-	/*
-	 * we are skipping array location 0 on purpose - this
-	 * is because a value of NOT_AVAILABLE is displayed
-	 * to the user as max_performance, but when the user
-	 * writes "max_performance", they actually want the
-	 * value to match MAX_PERFORMANCE.
-	 */
-	for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
-		const int len = strlen(link_pm_policy[i].name);
-		if (strncmp(link_pm_policy[i].name, buf, len) == 0) {
-			policy = link_pm_policy[i].value;
+	/* UNKNOWN is internal state, iterate from MAX_POWER */
+	for (policy = ATA_LPM_MAX_POWER;
+	     policy < ARRAY_SIZE(ata_lpm_policy_names); policy++) {
+		const char *name = ata_lpm_policy_names[policy];
+
+		if (strncmp(name, buf, strlen(name)) == 0)
 			break;
-		}
 	}
-	if (!policy)
+	if (policy == ARRAY_SIZE(ata_lpm_policy_names))
 		return -EINVAL;
 
 	ata_lpm_schedule(ap, policy);
 	return count;
 }
 
-static ssize_t
-ata_scsi_lpm_show(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t ata_scsi_lpm_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
 {
 	struct Scsi_Host *shost = class_to_shost(dev);
 	struct ata_port *ap = ata_shost_to_port(shost);
-	const char *policy =
-		ata_scsi_lpm_get(ap->pm_policy);
 
-	if (!policy)
+	if (ap->lpm_policy >= ARRAY_SIZE(ata_lpm_policy_names))
 		return -EINVAL;
 
-	return snprintf(buf, 23, "%s\n", policy);
+	return snprintf(buf, PAGE_SIZE, "%s\n",
+			ata_lpm_policy_names[ap->lpm_policy]);
 }
 DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
-		ata_scsi_lpm_show, ata_scsi_lpm_put);
+	    ata_scsi_lpm_show, ata_scsi_lpm_store);
 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
 
 static ssize_t ata_scsi_park_show(struct device *device,
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 142102b..1471462 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -100,8 +100,10 @@ extern int sata_link_init_spd(struct ata_link *link);
 extern int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg);
 extern int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg);
 extern struct ata_port *ata_port_alloc(struct ata_host *host);
-extern void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy);
-extern void ata_lpm_schedule(struct ata_port *ap, enum link_pm);
+extern void ata_dev_enable_pm(struct ata_device *dev,
+			      enum ata_lpm_policy policy);
+extern void ata_lpm_schedule(struct ata_port *ap,
+			     enum ata_lpm_policy policy);
 extern const char *sata_spd_string(unsigned int spd);
 
 /* libata-acpi.c */
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 89115f8..acfb650 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -196,7 +196,7 @@ enum {
 	ATA_FLAG_ACPI_SATA	= (1 << 17), /* need native SATA ACPI layout */
 	ATA_FLAG_AN		= (1 << 18), /* controller supports AN */
 	ATA_FLAG_PMP		= (1 << 19), /* controller supports PMP */
-	ATA_FLAG_IPM		= (1 << 20), /* driver can handle IPM */
+	ATA_FLAG_LPM		= (1 << 20), /* driver can handle LPM */
 	ATA_FLAG_EM		= (1 << 21), /* driver supports enclosure
 					      * management */
 	ATA_FLAG_SW_ACTIVITY	= (1 << 22), /* driver supports sw activity
@@ -376,7 +376,7 @@ enum {
 	ATA_HORKAGE_BROKEN_HPA	= (1 << 4),	/* Broken HPA */
 	ATA_HORKAGE_DISABLE	= (1 << 5),	/* Disable it */
 	ATA_HORKAGE_HPA_SIZE	= (1 << 6),	/* native size off by one */
-	ATA_HORKAGE_IPM		= (1 << 7),	/* Link PM problems */
+	ATA_HORKAGE_LPM		= (1 << 7),	/* Link PM problems */
 	ATA_HORKAGE_IVB		= (1 << 8),	/* cbl det validity bit bugs */
 	ATA_HORKAGE_STUCK_ERR	= (1 << 9),	/* stuck ERR on next PACKET */
 	ATA_HORKAGE_BRIDGE_OK	= (1 << 10),	/* no bridge limits */
@@ -463,6 +463,17 @@ enum ata_completion_errors {
 	AC_ERR_NCQ		= (1 << 10), /* marker for offending NCQ qc */
 };
 
+/*
+ * Link power management policy: If you alter this, you also need to
+ * alter libata-scsi.c (for the ascii descriptions)
+ */
+enum ata_lpm_policy {
+	ATA_LPM_UNKNOWN,
+	ATA_LPM_MAX_POWER,
+	ATA_LPM_MED_POWER,
+	ATA_LPM_MIN_POWER,
+};
+
 /* forward declarations */
 struct scsi_device;
 struct ata_port_operations;
@@ -477,16 +488,6 @@ typedef int (*ata_reset_fn_t)(struct ata_link *link, unsigned int *classes,
 			      unsigned long deadline);
 typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes);
 
-/*
- * host pm policy: If you alter this, you also need to alter libata-scsi.c
- * (for the ascii descriptions)
- */
-enum link_pm {
-	NOT_AVAILABLE,
-	MIN_POWER,
-	MAX_PERFORMANCE,
-	MEDIUM_POWER,
-};
 extern struct device_attribute dev_attr_link_power_management_policy;
 extern struct device_attribute dev_attr_unload_heads;
 extern struct device_attribute dev_attr_em_message_type;
@@ -770,7 +771,7 @@ struct ata_port {
 
 	pm_message_t		pm_mesg;
 	int			*pm_result;
-	enum link_pm		pm_policy;
+	enum ata_lpm_policy	lpm_policy;
 
 	struct timer_list	fastdrain_timer;
 	unsigned long		fastdrain_cnt;
@@ -836,7 +837,7 @@ struct ata_port_operations {
 	int  (*scr_write)(struct ata_link *link, unsigned int sc_reg, u32 val);
 	void (*pmp_attach)(struct ata_port *ap);
 	void (*pmp_detach)(struct ata_port *ap);
-	int  (*enable_pm)(struct ata_port *ap, enum link_pm policy);
+	int  (*enable_pm)(struct ata_port *ap, enum ata_lpm_policy policy);
 	void (*disable_pm)(struct ata_port *ap);
 
 	/*
-- 
1.7.1