[PATCH v3 5/6] ata: add ata port system PM callbacks

From: Lin Ming
Date: Wed Nov 23 2011 - 02:01:47 EST


Change ata_host_request_pm to ata_port_request_pm which performs
port suspend/resume.

Add ata port type driver which implements port PM callbacks.

Signed-off-by: Lin Ming <ming.m.lin@xxxxxxxxx>
---
drivers/ata/libata-core.c | 144 ++++++++++++++++++++-------------------
drivers/ata/libata-transport.c | 1 +
drivers/ata/libata.h | 1 +
3 files changed, 76 insertions(+), 70 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c04ad68..04c208e 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5234,112 +5234,116 @@ bool ata_link_offline(struct ata_link *link)
}

#ifdef CONFIG_PM
-static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
+static int ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
unsigned int action, unsigned int ehi_flags,
int wait)
{
+ struct ata_link *link;
unsigned long flags;
- int i, rc;
-
- for (i = 0; i < host->n_ports; i++) {
- struct ata_port *ap = host->ports[i];
- struct ata_link *link;
+ int rc;

- /* Previous resume operation might still be in
- * progress. Wait for PM_PENDING to clear.
- */
- if (ap->pflags & ATA_PFLAG_PM_PENDING) {
- ata_port_wait_eh(ap);
- WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
- }
+ /* Previous resume operation might still be in
+ * progress. Wait for PM_PENDING to clear.
+ */
+ if (ap->pflags & ATA_PFLAG_PM_PENDING) {
+ ata_port_wait_eh(ap);
+ WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
+ }

- /* request PM ops to EH */
- spin_lock_irqsave(ap->lock, flags);
+ /* request PM ops to EH */
+ spin_lock_irqsave(ap->lock, flags);

- ap->pm_mesg = mesg;
- if (wait) {
- rc = 0;
- ap->pm_result = &rc;
- }
+ ap->pm_mesg = mesg;
+ if (wait) {
+ rc = 0;
+ ap->pm_result = &rc;
+ }

- ap->pflags |= ATA_PFLAG_PM_PENDING;
- ata_for_each_link(link, ap, HOST_FIRST) {
- link->eh_info.action |= action;
- link->eh_info.flags |= ehi_flags;
- }
+ ap->pflags |= ATA_PFLAG_PM_PENDING;
+ ata_for_each_link(link, ap, HOST_FIRST) {
+ link->eh_info.action |= action;
+ link->eh_info.flags |= ehi_flags;
+ }

- ata_port_schedule_eh(ap);
+ ata_port_schedule_eh(ap);

- spin_unlock_irqrestore(ap->lock, flags);
+ spin_unlock_irqrestore(ap->lock, flags);

- /* wait and check result */
- if (wait) {
- ata_port_wait_eh(ap);
- WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
- if (rc)
- return rc;
- }
+ /* wait and check result */
+ if (wait) {
+ ata_port_wait_eh(ap);
+ WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
}

- return 0;
+ return rc;
}

+#define to_ata_port(d) container_of(d, struct ata_port, tdev)
+
+static int ata_port_suspend_common(struct device *dev)
+{
+ struct ata_port *ap = to_ata_port(dev);
+ int rc;
+
+ rc = ata_port_request_pm(ap, PMSG_SUSPEND, 0, ATA_EHI_QUIET, 1);
+ return rc;
+}
+
+static int ata_port_suspend(struct device *dev)
+{
+ if (pm_runtime_suspended(dev))
+ return 0;
+
+ return ata_port_suspend_common(dev);
+}
+
+static int ata_port_resume(struct device *dev)
+{
+ struct ata_port *ap = to_ata_port(dev);
+ int rc;
+
+ rc = ata_port_request_pm(ap, PMSG_ON, ATA_EH_RESET,
+ ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 1);
+ return rc;
+}
+
+static const struct dev_pm_ops ata_port_pm_ops = {
+ .suspend = ata_port_suspend,
+ .resume = ata_port_resume,
+};
+
/**
* ata_host_suspend - suspend host
* @host: host to suspend
* @mesg: PM message
*
- * Suspend @host. Actual operation is performed by EH. This
- * function requests EH to perform PM operations and waits for EH
- * to finish.
- *
- * LOCKING:
- * Kernel thread context (may sleep).
- *
- * RETURNS:
- * 0 on success, -errno on failure.
+ * Suspend @host. Actual operation is performed by port suspend.
*/
int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
{
- unsigned int ehi_flags = ATA_EHI_QUIET;
- int rc;
-
- /*
- * On some hardware, device fails to respond after spun down
- * for suspend. As the device won't be used before being
- * resumed, we don't need to touch the device. Ask EH to skip
- * the usual stuff and proceed directly to suspend.
- *
- * http://thread.gmane.org/gmane.linux.ide/46764
- */
- if (mesg.event == PM_EVENT_SUSPEND)
- ehi_flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_NO_RECOVERY;
-
- rc = ata_host_request_pm(host, mesg, 0, ehi_flags, 1);
- if (rc == 0)
- host->dev->power.power_state = mesg;
- return rc;
+ host->dev->power.power_state = mesg;
+ return 0;
}

/**
* ata_host_resume - resume host
* @host: host to resume
*
- * Resume @host. Actual operation is performed by EH. This
- * function requests EH to perform PM operations and returns.
- * Note that all resume operations are performed parallelly.
- *
- * LOCKING:
- * Kernel thread context (may sleep).
+ * Resume @host. Actual operation is performed by port resume.
*/
void ata_host_resume(struct ata_host *host)
{
- ata_host_request_pm(host, PMSG_ON, ATA_EH_RESET,
- ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
host->dev->power.power_state = PMSG_ON;
}
#endif

+struct device_type ata_port_type = {
+ .name = "ata_port",
+#ifdef CONFIG_PM
+ .pm = &ata_port_pm_ops,
+#endif
+};
+
/**
* ata_dev_init - Initialize an ata_device structure
* @dev: Device structure to initialize
diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c
index ce9dc62..3ceb3d9 100644
--- a/drivers/ata/libata-transport.c
+++ b/drivers/ata/libata-transport.c
@@ -279,6 +279,7 @@ int ata_tport_add(struct device *parent,
struct device *dev = &ap->tdev;

device_initialize(dev);
+ dev->type = &ata_port_type;

dev->parent = get_device(parent);
dev->release = ata_tport_release;
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 773de97..814486d 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -58,6 +58,7 @@ extern int atapi_passthru16;
extern int libata_fua;
extern int libata_noacpi;
extern int libata_allow_tpm;
+extern struct device_type ata_port_type;
extern struct ata_link *ata_dev_phys_link(struct ata_device *dev);
extern void ata_force_cbl(struct ata_port *ap);
extern u64 ata_tf_to_lba(const struct ata_taskfile *tf);
--
1.7.2.5

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