ahci: platform support for suspend/resume
Brian Norris [Fri, 18 Nov 2011 19:10:10 +0000 (11:10 -0800)]
Add platform hooks for custom suspend() and resume() functions. The
generic suspend/resume code in drivers/ata/ahci_platform.c is adapted
from the PCI version in drivers/ata/ahci.c.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/ahci_platform.c
include/linux/ahci_platform.h

index 43b8758..48be4e1 100644 (file)
@@ -202,6 +202,71 @@ static int __devexit ahci_remove(struct platform_device *pdev)
        return 0;
 }
 
+#ifdef CONFIG_PM
+static int ahci_suspend(struct device *dev)
+{
+       struct ahci_platform_data *pdata = dev_get_platdata(dev);
+       struct ata_host *host = dev_get_drvdata(dev);
+       struct ahci_host_priv *hpriv = host->private_data;
+       void __iomem *mmio = hpriv->mmio;
+       u32 ctl;
+       int rc;
+
+       if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
+               dev_err(dev, "firmware update required for suspend/resume\n");
+               return -EIO;
+       }
+
+       /*
+        * AHCI spec rev1.1 section 8.3.3:
+        * Software must disable interrupts prior to requesting a
+        * transition of the HBA to D3 state.
+        */
+       ctl = readl(mmio + HOST_CTL);
+       ctl &= ~HOST_IRQ_EN;
+       writel(ctl, mmio + HOST_CTL);
+       readl(mmio + HOST_CTL); /* flush */
+
+       rc = ata_host_suspend(host, PMSG_SUSPEND);
+       if (rc)
+               return rc;
+
+       if (pdata && pdata->suspend)
+               return pdata->suspend(dev);
+       return 0;
+}
+
+static int ahci_resume(struct device *dev)
+{
+       struct ahci_platform_data *pdata = dev_get_platdata(dev);
+       struct ata_host *host = dev_get_drvdata(dev);
+       int rc;
+
+       if (pdata && pdata->resume) {
+               rc = pdata->resume(dev);
+               if (rc)
+                       return rc;
+       }
+
+       if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
+               rc = ahci_reset_controller(host);
+               if (rc)
+                       return rc;
+
+               ahci_init_controller(host);
+       }
+
+       ata_host_resume(host);
+
+       return 0;
+}
+
+static struct dev_pm_ops ahci_pm_ops = {
+       .suspend                = &ahci_suspend,
+       .resume                 = &ahci_resume,
+};
+#endif
+
 static const struct of_device_id ahci_of_match[] = {
        { .compatible = "calxeda,hb-ahci", },
        {},
@@ -214,6 +279,9 @@ static struct platform_driver ahci_driver = {
                .name = "ahci",
                .owner = THIS_MODULE,
                .of_match_table = ahci_of_match,
+#ifdef CONFIG_PM
+               .pm = &ahci_pm_ops,
+#endif
        },
        .id_table       = ahci_devtype,
 };
index be3d9a7..73a2500 100644 (file)
@@ -23,6 +23,8 @@ struct ata_port_info;
 struct ahci_platform_data {
        int (*init)(struct device *dev, void __iomem *addr);
        void (*exit)(struct device *dev);
+       int (*suspend)(struct device *dev);
+       int (*resume)(struct device *dev);
        const struct ata_port_info *ata_port_info;
        unsigned int force_port_map;
        unsigned int mask_port_map;