Merge branch 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata

Pull libata updates from Tejun Heo:

 - ahci grew runtime power management support so that the controller can
   be turned off if no devices are attached.

 - sata_via isn't dead yet.  It got hotplug support and more refined
   workaround for certain WD drives.

 - Misc cleanups.  There's a merge from for-4.5-fixes to avoid confusing
   conflicts in ahci PCI ID table.

* 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ata: ahci_xgene: dereferencing uninitialized pointer in probe
  AHCI: Remove obsolete Intel Lewisburg SATA RAID device IDs
  ata: sata_rcar: Use ARCH_RENESAS
  sata_via: Implement hotplug for VT6421
  sata_via: Apply WD workaround only when needed on VT6421
  ahci: Add runtime PM support for the host controller
  ahci: Add functions to manage runtime PM of AHCI ports
  ahci: Convert driver to use modern PM hooks
  ahci: Cache host controller version
  scsi: Drop runtime PM usage count after host is added
  scsi: Set request queue runtime PM status back to active on resume
  block: Add blk_set_runtime_active()
  ata: ahci_mvebu: add support for Armada 3700 variant
  libata: fix unbalanced spin_lock_irqsave/spin_unlock_irq() in ata_scsi_park_show()
  libata: support AHCI on OCTEON platform

18 files changed, 475 insertions, 57 deletions

diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
index c2340eeeb97f..3d84dcae8475 100644
--- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
+++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
@@ -11,6 +11,7 @@ Required properties:
 - compatible        : compatible string, one of:
   - "allwinner,sun4i-a10-ahci"
   - "hisilicon,hisi-ahci"
+  - "cavium,octeon-7130-ahci"
   - "ibm,476gtr-ahci"
   - "marvell,armada-380-ahci"
   - "snps,dwc-ahci"
diff --git a/Documentation/devicetree/bindings/mips/cavium/sata-uctl.txt b/Documentation/devicetree/bindings/mips/cavium/sata-uctl.txt
new file mode 100644
index 000000000000..3bd3c2f0b9b1
--- /dev/null
+++ b/Documentation/devicetree/bindings/mips/cavium/sata-uctl.txt
@@ -0,0 +1,42 @@
+* UCTL SATA controller glue
+
+UCTL is the bridge unit between the I/O interconnect (an internal bus)
+and the SATA AHCI host controller (UAHC). It performs the following functions:
+        - provides interfaces for the applications to access the UAHC AHCI
+          registers on the CN71XX I/O space.
+        - provides a bridge for UAHC to fetch AHCI command table entries and data
+          buffers from Level 2 Cache.
+        - posts interrupts to the CIU.
+        - contains registers that:
+                - control the behavior of the UAHC
+                - control the clock/reset generation to UAHC
+                - control endian swapping for all UAHC registers and DMA accesses
+
+Properties:
+
+- compatible: "cavium,octeon-7130-sata-uctl"
+
+  Compatibility with the cn7130 SOC.
+
+- reg: The base address of the UCTL register bank.
+
+- #address-cells, #size-cells, ranges and dma-ranges must be present and hold
+        suitable values to map all child nodes.
+
+Example:
+
+        uctl@118006c000000 {
+                compatible = "cavium,octeon-7130-sata-uctl";
+                reg = <0x11800 0x6c000000 0x0 0x100>;
+                ranges; /* Direct mapping */
+                dma-ranges;
+                #address-cells = <2>;
+                #size-cells = <2>;
+
+                sata: sata@16c0000000000 {
+                        compatible = "cavium,octeon-7130-ahci";
+                        reg = <0x16c00 0x00000000 0x0 0x200>;
+                        interrupt-parent = <&cibsata>;
+                        interrupts = <2 4>; /* Bit: 2, level */
+                };
+        };
diff --git a/arch/mips/include/asm/octeon/cvmx.h b/arch/mips/include/asm/octeon/cvmx.h
index 774bb45834cb..19e139c9f337 100644
--- a/arch/mips/include/asm/octeon/cvmx.h
+++ b/arch/mips/include/asm/octeon/cvmx.h
@@ -275,6 +275,11 @@ static inline void cvmx_write_csr(uint64_t csr_addr, uint64_t val)
                 cvmx_read64(CVMX_MIO_BOOT_BIST_STAT);
 }
 
+static inline void cvmx_writeq_csr(void __iomem *csr_addr, uint64_t val)
+{
+        cvmx_write_csr((__force uint64_t)csr_addr, val);
+}
+
 static inline void cvmx_write_io(uint64_t io_addr, uint64_t val)
 {
         cvmx_write64(io_addr, val);
@@ -287,6 +292,10 @@ static inline uint64_t cvmx_read_csr(uint64_t csr_addr)
         return val;
 }
 
+static inline uint64_t cvmx_readq_csr(void __iomem *csr_addr)
+{
+        return cvmx_read_csr((__force uint64_t) csr_addr);
+}
 
 static inline void cvmx_send_single(uint64_t data)
 {
diff --git a/block/blk-core.c b/block/blk-core.c
index 45f4d7efbf34..827f8badd143 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -3529,6 +3529,30 @@ void blk_post_runtime_resume(struct request_queue *q, int err)
         spin_unlock_irq(q->queue_lock);
 }
 EXPORT_SYMBOL(blk_post_runtime_resume);
+
+/**
+ * blk_set_runtime_active - Force runtime status of the queue to be active
+ * @q: the queue of the device
+ *
+ * If the device is left runtime suspended during system suspend the resume
+ * hook typically resumes the device and corrects runtime status
+ * accordingly. However, that does not affect the queue runtime PM status
+ * which is still "suspended". This prevents processing requests from the
+ * queue.
+ *
+ * This function can be used in driver's resume hook to correct queue
+ * runtime PM status and re-enable peeking requests from the queue. It
+ * should be called before first request is added to the queue.
+ */
+void blk_set_runtime_active(struct request_queue *q)
+{
+        spin_lock_irq(q->queue_lock);
+        q->rpm_status = RPM_ACTIVE;
+        pm_runtime_mark_last_busy(q->dev);
+        pm_request_autosuspend(q->dev);
+        spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_set_runtime_active);
 #endif
 
 int __init blk_dev_init(void)
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 861643ea91b5..5083f85efea7 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -151,6 +151,15 @@ config AHCI_MVEBU
 
           If unsure, say N.
 
+config AHCI_OCTEON
+        tristate "Cavium Octeon Soc Serial ATA"
+        depends on SATA_AHCI_PLATFORM && CAVIUM_OCTEON_SOC
+        default y
+        help
+          This option enables support for Cavium Octeon SoC Serial ATA.
+
+          If unsure, say N.
+
 config AHCI_SUNXI
         tristate "Allwinner sunxi AHCI SATA support"
         depends on ARCH_SUNXI
@@ -355,7 +364,7 @@ config SATA_PROMISE
 
 config SATA_RCAR
         tristate "Renesas R-Car SATA support"
-        depends on ARCH_SHMOBILE || COMPILE_TEST
+        depends on ARCH_RENESAS || COMPILE_TEST
         help
           This option enables support for Renesas R-Car Serial ATA.
 
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index af45effac18c..18579521464e 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_AHCI_CEVA)		+= ahci_ceva.o libahci.o libahci_platform.o
 obj-$(CONFIG_AHCI_DA850)        += ahci_da850.o libahci.o libahci_platform.o
 obj-$(CONFIG_AHCI_IMX)          += ahci_imx.o libahci.o libahci_platform.o
 obj-$(CONFIG_AHCI_MVEBU)        += ahci_mvebu.o libahci.o libahci_platform.o
+obj-$(CONFIG_AHCI_OCTEON)       += ahci_octeon.o
 obj-$(CONFIG_AHCI_SUNXI)        += ahci_sunxi.o libahci.o libahci_platform.o
 obj-$(CONFIG_AHCI_ST)           += ahci_st.o libahci.o libahci_platform.o
 obj-$(CONFIG_AHCI_TEGRA)        += ahci_tegra.o libahci.o libahci_platform.o
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 146dc0b8ec61..a83bbcc58b4c 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -85,6 +85,7 @@ enum board_ids {
 };
 
 static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
+static void ahci_remove_one(struct pci_dev *dev);
 static int ahci_vt8251_hardreset(struct ata_link *link, unsigned int *class,
                                  unsigned long deadline);
 static int ahci_avn_hardreset(struct ata_link *link, unsigned int *class,
@@ -94,9 +95,13 @@ static bool is_mcp89_apple(struct pci_dev *pdev);
 static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
                                 unsigned long deadline);
 #ifdef CONFIG_PM
-static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg);
-static int ahci_pci_device_resume(struct pci_dev *pdev);
+static int ahci_pci_device_runtime_suspend(struct device *dev);
+static int ahci_pci_device_runtime_resume(struct device *dev);
+#ifdef CONFIG_PM_SLEEP
+static int ahci_pci_device_suspend(struct device *dev);
+static int ahci_pci_device_resume(struct device *dev);
 #endif
+#endif /* CONFIG_PM */
 
 static struct scsi_host_template ahci_sht = {
         AHCI_SHT("ahci"),
@@ -371,15 +376,11 @@ static const struct pci_device_id ahci_pci_tbl[] = {
         { PCI_VDEVICE(INTEL, 0x2826), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0x2827), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa182), board_ahci }, /* Lewisburg AHCI*/
-        { PCI_VDEVICE(INTEL, 0xa184), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa186), board_ahci }, /* Lewisburg RAID*/
-        { PCI_VDEVICE(INTEL, 0xa18e), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa1d2), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa1d6), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa202), board_ahci }, /* Lewisburg AHCI*/
-        { PCI_VDEVICE(INTEL, 0xa204), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa206), board_ahci }, /* Lewisburg RAID*/
-        { PCI_VDEVICE(INTEL, 0xa20e), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa252), board_ahci }, /* Lewisburg RAID*/
         { PCI_VDEVICE(INTEL, 0xa256), board_ahci }, /* Lewisburg RAID*/
 
@@ -563,16 +564,20 @@ static const struct pci_device_id ahci_pci_tbl[] = {
         { }     /* terminate list */
 };
 
+static const struct dev_pm_ops ahci_pci_pm_ops = {
+        SET_SYSTEM_SLEEP_PM_OPS(ahci_pci_device_suspend, ahci_pci_device_resume)
+        SET_RUNTIME_PM_OPS(ahci_pci_device_runtime_suspend,
+                           ahci_pci_device_runtime_resume, NULL)
+};
 
 static struct pci_driver ahci_pci_driver = {
         .name                   = DRV_NAME,
         .id_table               = ahci_pci_tbl,
         .probe                  = ahci_init_one,
-        .remove                 = ata_pci_remove_one,
-#ifdef CONFIG_PM
-        .suspend                = ahci_pci_device_suspend,
-        .resume                 = ahci_pci_device_resume,
-#endif
+        .remove                 = ahci_remove_one,
+        .driver = {
+                .pm             = &ahci_pci_pm_ops,
+        },
 };
 
 #if defined(CONFIG_PATA_MARVELL) || defined(CONFIG_PATA_MARVELL_MODULE)
@@ -801,42 +806,66 @@ static int ahci_avn_hardreset(struct ata_link *link, unsigned int *class,
 
 
 #ifdef CONFIG_PM
-static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
+static void ahci_pci_disable_interrupts(struct ata_host *host)
 {
-        struct ata_host *host = pci_get_drvdata(pdev);
         struct ahci_host_priv *hpriv = host->private_data;
         void __iomem *mmio = hpriv->mmio;
         u32 ctl;
 
-        if (mesg.event & PM_EVENT_SUSPEND &&
-            hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
-                dev_err(&pdev->dev,
-                        "BIOS 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 */
+}
 
-        if (mesg.event & PM_EVENT_SLEEP) {
-                /* 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 */
-        }
+static int ahci_pci_device_runtime_suspend(struct device *dev)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct ata_host *host = pci_get_drvdata(pdev);
 
-        return ata_pci_device_suspend(pdev, mesg);
+        ahci_pci_disable_interrupts(host);
+        return 0;
 }
 
-static int ahci_pci_device_resume(struct pci_dev *pdev)
+static int ahci_pci_device_runtime_resume(struct device *dev)
 {
+        struct pci_dev *pdev = to_pci_dev(dev);
         struct ata_host *host = pci_get_drvdata(pdev);
         int rc;
 
-        rc = ata_pci_device_do_resume(pdev);
+        rc = ahci_pci_reset_controller(host);
         if (rc)
                 return rc;
+        ahci_pci_init_controller(host);
+        return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ahci_pci_device_suspend(struct device *dev)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct ata_host *host = pci_get_drvdata(pdev);
+        struct ahci_host_priv *hpriv = host->private_data;
+
+        if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
+                dev_err(&pdev->dev,
+                        "BIOS update required for suspend/resume\n");
+                return -EIO;
+        }
+
+        ahci_pci_disable_interrupts(host);
+        return ata_host_suspend(host, PMSG_SUSPEND);
+}
+
+static int ahci_pci_device_resume(struct device *dev)
+{
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct ata_host *host = pci_get_drvdata(pdev);
+        int rc;
 
         /* Apple BIOS helpfully mangles the registers on resume */
         if (is_mcp89_apple(pdev))
@@ -856,6 +885,8 @@ static int ahci_pci_device_resume(struct pci_dev *pdev)
 }
 #endif
 
+#endif /* CONFIG_PM */
+
 static int ahci_configure_dma_masks(struct pci_dev *pdev, int using_dac)
 {
         int rc;
@@ -1718,7 +1749,18 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
         pci_set_master(pdev);
 
-        return ahci_host_activate(host, &ahci_sht);
+        rc = ahci_host_activate(host, &ahci_sht);
+        if (rc)
+                return rc;
+
+        pm_runtime_put_noidle(&pdev->dev);
+        return 0;
+}
+
+static void ahci_remove_one(struct pci_dev *pdev)
+{
+        pm_runtime_get_noresume(&pdev->dev);
+        ata_pci_remove_one(pdev);
 }
 
 module_pci_driver(ahci_pci_driver);
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 167ba7e3b92e..70b06bcfb7e3 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -335,6 +335,7 @@ struct ahci_host_priv {
         void __iomem *          mmio;           /* bus-independent mem map */
         u32                     cap;            /* cap to use */
         u32                     cap2;           /* cap2 to use */
+        u32                     version;        /* cached version */
         u32                     port_map;       /* port map to use */
         u32                     saved_cap;      /* saved initial cap */
         u32                     saved_cap2;     /* saved initial cap2 */
diff --git a/drivers/ata/ahci_mvebu.c b/drivers/ata/ahci_mvebu.c
index f7a7fa81740e..de7128d81e9c 100644
--- a/drivers/ata/ahci_mvebu.c
+++ b/drivers/ata/ahci_mvebu.c
@@ -112,12 +112,15 @@ static int ahci_mvebu_probe(struct platform_device *pdev)
         if (rc)
                 return rc;
 
-        dram = mv_mbus_dram_info();
-        if (!dram)
-                return -ENODEV;
+        if (of_device_is_compatible(pdev->dev.of_node,
+                                    "marvell,armada-380-ahci")) {
+                dram = mv_mbus_dram_info();
+                if (!dram)
+                        return -ENODEV;
 
-        ahci_mvebu_mbus_config(hpriv, dram);
-        ahci_mvebu_regret_option(hpriv);
+                ahci_mvebu_mbus_config(hpriv, dram);
+                ahci_mvebu_regret_option(hpriv);
+        }
 
         rc = ahci_platform_init_host(pdev, hpriv, &ahci_mvebu_port_info,
                                      &ahci_platform_sht);
@@ -133,6 +136,7 @@ disable_resources:
 
 static const struct of_device_id ahci_mvebu_of_match[] = {
         { .compatible = "marvell,armada-380-ahci", },
+        { .compatible = "marvell,armada-3700-ahci", },
         { },
 };
 MODULE_DEVICE_TABLE(of, ahci_mvebu_of_match);
diff --git a/drivers/ata/ahci_octeon.c b/drivers/ata/ahci_octeon.c
new file mode 100644
index 000000000000..ea865fe953e1
--- /dev/null
+++ b/drivers/ata/ahci_octeon.c
@@ -0,0 +1,105 @@
+/*
+ * SATA glue for Cavium Octeon III SOCs.
+ *
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2010-2015 Cavium Networks
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/bitfield.h>
+
+#define CVMX_SATA_UCTL_SHIM_CFG         0xE8
+
+#define SATA_UCTL_ENDIAN_MODE_BIG       1
+#define SATA_UCTL_ENDIAN_MODE_LITTLE    0
+#define SATA_UCTL_ENDIAN_MODE_MASK      3
+
+#define SATA_UCTL_DMA_ENDIAN_MODE_SHIFT 8
+#define SATA_UCTL_CSR_ENDIAN_MODE_SHIFT 0
+#define SATA_UCTL_DMA_READ_CMD_SHIFT    12
+
+static int ahci_octeon_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct device_node *node = dev->of_node;
+        struct resource *res;
+        void __iomem *base;
+        u64 cfg;
+        int ret;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                dev_err(&pdev->dev, "Platform resource[0] is missing\n");
+                return -ENODEV;
+        }
+
+        base = devm_ioremap_resource(&pdev->dev, res);
+        if (IS_ERR(base))
+                return PTR_ERR(base);
+
+        cfg = cvmx_readq_csr(base + CVMX_SATA_UCTL_SHIM_CFG);
+
+        cfg &= ~(SATA_UCTL_ENDIAN_MODE_MASK << SATA_UCTL_DMA_ENDIAN_MODE_SHIFT);
+        cfg &= ~(SATA_UCTL_ENDIAN_MODE_MASK << SATA_UCTL_CSR_ENDIAN_MODE_SHIFT);
+
+#ifdef __BIG_ENDIAN
+        cfg |= SATA_UCTL_ENDIAN_MODE_BIG << SATA_UCTL_DMA_ENDIAN_MODE_SHIFT;
+        cfg |= SATA_UCTL_ENDIAN_MODE_BIG << SATA_UCTL_CSR_ENDIAN_MODE_SHIFT;
+#else
+        cfg |= SATA_UCTL_ENDIAN_MODE_LITTLE << SATA_UCTL_DMA_ENDIAN_MODE_SHIFT;
+        cfg |= SATA_UCTL_ENDIAN_MODE_LITTLE << SATA_UCTL_CSR_ENDIAN_MODE_SHIFT;
+#endif
+
+        cfg |= 1 << SATA_UCTL_DMA_READ_CMD_SHIFT;
+
+        cvmx_writeq_csr(base + CVMX_SATA_UCTL_SHIM_CFG, cfg);
+
+        if (!node) {
+                dev_err(dev, "no device node, failed to add octeon sata\n");
+                return -ENODEV;
+        }
+
+        ret = of_platform_populate(node, NULL, NULL, dev);
+        if (ret) {
+                dev_err(dev, "failed to add ahci-platform core\n");
+                return ret;
+        }
+
+        return 0;
+}
+
+static int ahci_octeon_remove(struct platform_device *pdev)
+{
+        return 0;
+}
+
+static const struct of_device_id octeon_ahci_match[] = {
+        { .compatible = "cavium,octeon-7130-sata-uctl", },
+        {},
+};
+MODULE_DEVICE_TABLE(of, octeon_ahci_match);
+
+static struct platform_driver ahci_octeon_driver = {
+        .probe          = ahci_octeon_probe,
+        .remove         = ahci_octeon_remove,
+        .driver         = {
+                .name   = "octeon-ahci",
+                .of_match_table = octeon_ahci_match,
+        },
+};
+
+module_platform_driver(ahci_octeon_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Cavium, Inc. <support@cavium.com>");
+MODULE_DESCRIPTION("Cavium Inc. sata config.");
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 04975b851c23..40442332bfa7 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -76,6 +76,7 @@ static const struct of_device_id ahci_of_match[] = {
         { .compatible = "ibm,476gtr-ahci", },
         { .compatible = "snps,dwc-ahci", },
         { .compatible = "hisilicon,hisi-ahci", },
+        { .compatible = "cavium,octeon-7130-ahci", },
         {},
 };
 MODULE_DEVICE_TABLE(of, ahci_of_match);
diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
index 8e3f7faf00d3..73b19b277138 100644
--- a/drivers/ata/ahci_xgene.c
+++ b/drivers/ata/ahci_xgene.c
@@ -821,9 +821,9 @@ static int xgene_ahci_probe(struct platform_device *pdev)
                                 dev_warn(&pdev->dev, "%s: Error reading device info. Assume version1\n",
                                         __func__);
                                 version = XGENE_AHCI_V1;
-                        }
-                        if (info->valid & ACPI_VALID_CID)
+                        } else if (info->valid & ACPI_VALID_CID) {
                                 version = XGENE_AHCI_V2;
+                        }
                 }
         }
 #endif
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 85ea5142a095..3982054060b8 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -225,6 +225,31 @@ static void ahci_enable_ahci(void __iomem *mmio)
         WARN_ON(1);
 }
 
+/**
+ *      ahci_rpm_get_port - Make sure the port is powered on
+ *      @ap: Port to power on
+ *
+ *      Whenever there is need to access the AHCI host registers outside of
+ *      normal execution paths, call this function to make sure the host is
+ *      actually powered on.
+ */
+static int ahci_rpm_get_port(struct ata_port *ap)
+{
+        return pm_runtime_get_sync(ap->dev);
+}
+
+/**
+ *      ahci_rpm_put_port - Undoes ahci_rpm_get_port()
+ *      @ap: Port to power down
+ *
+ *      Undoes ahci_rpm_get_port() and possibly powers down the AHCI host
+ *      if it has no more active users.
+ */
+static void ahci_rpm_put_port(struct ata_port *ap)
+{
+        pm_runtime_put(ap->dev);
+}
+
 static ssize_t ahci_show_host_caps(struct device *dev,
                                    struct device_attribute *attr, char *buf)
 {
@@ -251,9 +276,8 @@ static ssize_t ahci_show_host_version(struct device *dev,
         struct Scsi_Host *shost = class_to_shost(dev);
         struct ata_port *ap = ata_shost_to_port(shost);
         struct ahci_host_priv *hpriv = ap->host->private_data;
-        void __iomem *mmio = hpriv->mmio;
 
-        return sprintf(buf, "%x\n", readl(mmio + HOST_VERSION));
+        return sprintf(buf, "%x\n", hpriv->version);
 }
 
 static ssize_t ahci_show_port_cmd(struct device *dev,
@@ -262,8 +286,13 @@ static ssize_t ahci_show_port_cmd(struct device *dev,
         struct Scsi_Host *shost = class_to_shost(dev);
         struct ata_port *ap = ata_shost_to_port(shost);
         void __iomem *port_mmio = ahci_port_base(ap);
+        ssize_t ret;
+
+        ahci_rpm_get_port(ap);
+        ret = sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
+        ahci_rpm_put_port(ap);
 
-        return sprintf(buf, "%x\n", readl(port_mmio + PORT_CMD));
+        return ret;
 }
 
 static ssize_t ahci_read_em_buffer(struct device *dev,
@@ -279,17 +308,20 @@ static ssize_t ahci_read_em_buffer(struct device *dev,
         size_t count;
         int i;
 
+        ahci_rpm_get_port(ap);
         spin_lock_irqsave(ap->lock, flags);
 
         em_ctl = readl(mmio + HOST_EM_CTL);
         if (!(ap->flags & ATA_FLAG_EM) || em_ctl & EM_CTL_XMT ||
             !(hpriv->em_msg_type & EM_MSG_TYPE_SGPIO)) {
                 spin_unlock_irqrestore(ap->lock, flags);
+                ahci_rpm_put_port(ap);
                 return -EINVAL;
         }
 
         if (!(em_ctl & EM_CTL_MR)) {
                 spin_unlock_irqrestore(ap->lock, flags);
+                ahci_rpm_put_port(ap);
                 return -EAGAIN;
         }
 
@@ -317,6 +349,7 @@ static ssize_t ahci_read_em_buffer(struct device *dev,
         }
 
         spin_unlock_irqrestore(ap->lock, flags);
+        ahci_rpm_put_port(ap);
 
         return i;
 }
@@ -341,11 +374,13 @@ static ssize_t ahci_store_em_buffer(struct device *dev,
             size % 4 || size > hpriv->em_buf_sz)
                 return -EINVAL;
 
+        ahci_rpm_get_port(ap);
         spin_lock_irqsave(ap->lock, flags);
 
         em_ctl = readl(mmio + HOST_EM_CTL);
         if (em_ctl & EM_CTL_TM) {
                 spin_unlock_irqrestore(ap->lock, flags);
+                ahci_rpm_put_port(ap);
                 return -EBUSY;
         }
 
@@ -358,6 +393,7 @@ static ssize_t ahci_store_em_buffer(struct device *dev,
         writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
 
         spin_unlock_irqrestore(ap->lock, flags);
+        ahci_rpm_put_port(ap);
 
         return size;
 }
@@ -371,7 +407,9 @@ static ssize_t ahci_show_em_supported(struct device *dev,
         void __iomem *mmio = hpriv->mmio;
         u32 em_ctl;
 
+        ahci_rpm_get_port(ap);
         em_ctl = readl(mmio + HOST_EM_CTL);
+        ahci_rpm_put_port(ap);
 
         return sprintf(buf, "%s%s%s%s\n",
                        em_ctl & EM_CTL_LED ? "led " : "",
@@ -509,6 +547,7 @@ void ahci_save_initial_config(struct device *dev, struct ahci_host_priv *hpriv)
         /* record values to use during operation */
         hpriv->cap = cap;
         hpriv->cap2 = cap2;
+        hpriv->version = readl(mmio + HOST_VERSION);
         hpriv->port_map = port_map;
 
         if (!hpriv->start_engine)
@@ -1014,6 +1053,7 @@ static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
         else
                 return -EINVAL;
 
+        ahci_rpm_get_port(ap);
         spin_lock_irqsave(ap->lock, flags);
 
         /*
@@ -1023,6 +1063,7 @@ static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
         em_ctl = readl(mmio + HOST_EM_CTL);
         if (em_ctl & EM_CTL_TM) {
                 spin_unlock_irqrestore(ap->lock, flags);
+                ahci_rpm_put_port(ap);
                 return -EBUSY;
         }
 
@@ -1050,6 +1091,8 @@ static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state,
         emp->led_state = state;
 
         spin_unlock_irqrestore(ap->lock, flags);
+        ahci_rpm_put_port(ap);
+
         return size;
 }
 
@@ -2215,6 +2258,8 @@ static void ahci_pmp_detach(struct ata_port *ap)
 
 int ahci_port_resume(struct ata_port *ap)
 {
+        ahci_rpm_get_port(ap);
+
         ahci_power_up(ap);
         ahci_start_port(ap);
 
@@ -2241,6 +2286,7 @@ static int ahci_port_suspend(struct ata_port *ap, pm_message_t mesg)
                 ata_port_freeze(ap);
         }
 
+        ahci_rpm_put_port(ap);
         return rc;
 }
 #endif
@@ -2356,11 +2402,10 @@ static void ahci_port_stop(struct ata_port *ap)
 void ahci_print_info(struct ata_host *host, const char *scc_s)
 {
         struct ahci_host_priv *hpriv = host->private_data;
-        void __iomem *mmio = hpriv->mmio;
         u32 vers, cap, cap2, impl, speed;
         const char *speed_s;
 
-        vers = readl(mmio + HOST_VERSION);
+        vers = hpriv->version;
         cap = hpriv->cap;
         cap2 = hpriv->cap2;
         impl = hpriv->port_map;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index e417e1a1d02c..567859ce0512 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -174,13 +174,13 @@ static ssize_t ata_scsi_park_show(struct device *device,
         struct ata_port *ap;
         struct ata_link *link;
         struct ata_device *dev;
-        unsigned long flags, now;
+        unsigned long now;
         unsigned int uninitialized_var(msecs);
         int rc = 0;
 
         ap = ata_shost_to_port(sdev->host);
 
-        spin_lock_irqsave(ap->lock, flags);
+        spin_lock_irq(ap->lock);
         dev = ata_scsi_find_dev(ap, sdev);
         if (!dev) {
                 rc = -ENODEV;
diff --git a/drivers/ata/sata_via.c b/drivers/ata/sata_via.c
index 17d31fc009ab..0636d84fbefe 100644
--- a/drivers/ata/sata_via.c
+++ b/drivers/ata/sata_via.c
@@ -61,6 +61,7 @@ enum {
         SATA_CHAN_ENAB          = 0x40, /* SATA channel enable */
         SATA_INT_GATE           = 0x41, /* SATA interrupt gating */
         SATA_NATIVE_MODE        = 0x42, /* Native mode enable */
+        SVIA_MISC_3             = 0x46, /* Miscellaneous Control III */
         PATA_UDMA_TIMING        = 0xB3, /* PATA timing for DMA/ cable detect */
         PATA_PIO_TIMING         = 0xAB, /* PATA timing register */
 
@@ -71,9 +72,18 @@ enum {
         NATIVE_MODE_ALL         = (1 << 7) | (1 << 6) | (1 << 5) | (1 << 4),
 
         SATA_EXT_PHY            = (1 << 6), /* 0==use PATA, 1==ext phy */
+
+        SATA_HOTPLUG            = (1 << 5), /* enable IRQ on hotplug */
+};
+
+struct svia_priv {
+        bool                    wd_workaround;
 };
 
 static int svia_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
+#ifdef CONFIG_PM_SLEEP
+static int svia_pci_device_resume(struct pci_dev *pdev);
+#endif
 static int svia_scr_read(struct ata_link *link, unsigned int sc_reg, u32 *val);
 static int svia_scr_write(struct ata_link *link, unsigned int sc_reg, u32 val);
 static int vt8251_scr_read(struct ata_link *link, unsigned int scr, u32 *val);
@@ -85,6 +95,7 @@ static void vt6420_bmdma_start(struct ata_queued_cmd *qc);
 static int vt6421_pata_cable_detect(struct ata_port *ap);
 static void vt6421_set_pio_mode(struct ata_port *ap, struct ata_device *adev);
 static void vt6421_set_dma_mode(struct ata_port *ap, struct ata_device *adev);
+static void vt6421_error_handler(struct ata_port *ap);
 
 static const struct pci_device_id svia_pci_tbl[] = {
         { PCI_VDEVICE(VIA, 0x5337), vt6420 },
@@ -105,7 +116,7 @@ static struct pci_driver svia_pci_driver = {
         .probe                  = svia_init_one,
 #ifdef CONFIG_PM_SLEEP
         .suspend                = ata_pci_device_suspend,
-        .resume                 = ata_pci_device_resume,
+        .resume                 = svia_pci_device_resume,
 #endif
         .remove                 = ata_pci_remove_one,
 };
@@ -137,6 +148,7 @@ static struct ata_port_operations vt6421_sata_ops = {
         .inherits               = &svia_base_ops,
         .scr_read               = svia_scr_read,
         .scr_write              = svia_scr_write,
+        .error_handler          = vt6421_error_handler,
 };
 
 static struct ata_port_operations vt8251_ops = {
@@ -536,7 +548,67 @@ static int vt8251_prepare_host(struct pci_dev *pdev, struct ata_host **r_host)
         return 0;
 }
 
-static void svia_configure(struct pci_dev *pdev, int board_id)
+static void svia_wd_fix(struct pci_dev *pdev)
+{
+        u8 tmp8;
+
+        pci_read_config_byte(pdev, 0x52, &tmp8);
+        pci_write_config_byte(pdev, 0x52, tmp8 | BIT(2));
+}
+
+static irqreturn_t vt6421_interrupt(int irq, void *dev_instance)
+{
+        struct ata_host *host = dev_instance;
+        irqreturn_t rc = ata_bmdma_interrupt(irq, dev_instance);
+
+        /* if the IRQ was not handled, it might be a hotplug IRQ */
+        if (rc != IRQ_HANDLED) {
+                u32 serror;
+                unsigned long flags;
+
+                spin_lock_irqsave(&host->lock, flags);
+                /* check for hotplug on port 0 */
+                svia_scr_read(&host->ports[0]->link, SCR_ERROR, &serror);
+                if (serror & SERR_PHYRDY_CHG) {
+                        ata_ehi_hotplugged(&host->ports[0]->link.eh_info);
+                        ata_port_freeze(host->ports[0]);
+                        rc = IRQ_HANDLED;
+                }
+                /* check for hotplug on port 1 */
+                svia_scr_read(&host->ports[1]->link, SCR_ERROR, &serror);
+                if (serror & SERR_PHYRDY_CHG) {
+                        ata_ehi_hotplugged(&host->ports[1]->link.eh_info);
+                        ata_port_freeze(host->ports[1]);
+                        rc = IRQ_HANDLED;
+                }
+                spin_unlock_irqrestore(&host->lock, flags);
+        }
+
+        return rc;
+}
+
+static void vt6421_error_handler(struct ata_port *ap)
+{
+        struct svia_priv *hpriv = ap->host->private_data;
+        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+        u32 serror;
+
+        /* see svia_configure() for description */
+        if (!hpriv->wd_workaround) {
+                svia_scr_read(&ap->link, SCR_ERROR, &serror);
+                if (serror == 0x1000500) {
+                        ata_port_warn(ap, "Incompatible drive: enabling workaround. This slows down transfer rate to ~60 MB/s");
+                        svia_wd_fix(pdev);
+                        hpriv->wd_workaround = true;
+                        ap->link.eh_context.i.flags |= ATA_EHI_QUIET;
+                }
+        }
+
+        ata_sff_error_handler(ap);
+}
+
+static void svia_configure(struct pci_dev *pdev, int board_id,
+                           struct svia_priv *hpriv)
 {
         u8 tmp8;
 
@@ -572,6 +644,16 @@ static void svia_configure(struct pci_dev *pdev, int board_id)
                 pci_write_config_byte(pdev, SATA_NATIVE_MODE, tmp8);
         }
 
+        /* enable IRQ on hotplug */
+        pci_read_config_byte(pdev, SVIA_MISC_3, &tmp8);
+        if ((tmp8 & SATA_HOTPLUG) != SATA_HOTPLUG) {
+                dev_dbg(&pdev->dev,
+                        "enabling SATA hotplug (0x%x)\n",
+                        (int) tmp8);
+                tmp8 |= SATA_HOTPLUG;
+                pci_write_config_byte(pdev, SVIA_MISC_3, tmp8);
+        }
+
         /*
          * vt6420/1 has problems talking to some drives.  The following
          * is the fix from Joseph Chan <JosephChan@via.com.tw>.
@@ -593,11 +675,15 @@ static void svia_configure(struct pci_dev *pdev, int board_id)
          * https://bugzilla.kernel.org/show_bug.cgi?id=15173
          * http://article.gmane.org/gmane.linux.ide/46352
          * http://thread.gmane.org/gmane.linux.kernel/1062139
+         *
+         * As the fix slows down data transfer, apply it only if the error
+         * actually appears - see vt6421_error_handler()
+         * Apply the fix always on vt6420 as we don't know if SCR_ERROR can be
+         * read safely.
          */
-        if (board_id == vt6420 || board_id == vt6421) {
-                pci_read_config_byte(pdev, 0x52, &tmp8);
-                tmp8 |= 1 << 2;
-                pci_write_config_byte(pdev, 0x52, tmp8);
+        if (board_id == vt6420) {
+                svia_wd_fix(pdev);
+                hpriv->wd_workaround = true;
         }
 }
 
@@ -608,6 +694,7 @@ static int svia_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
         struct ata_host *host = NULL;
         int board_id = (int) ent->driver_data;
         const unsigned *bar_sizes;
+        struct svia_priv *hpriv;
 
         ata_print_version_once(&pdev->dev, DRV_VERSION);
 
@@ -647,11 +734,39 @@ static int svia_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
         if (rc)
                 return rc;
 
-        svia_configure(pdev, board_id);
+        hpriv = devm_kzalloc(&pdev->dev, sizeof(*hpriv), GFP_KERNEL);
+        if (!hpriv)
+                return -ENOMEM;
+        host->private_data = hpriv;
+
+        svia_configure(pdev, board_id, hpriv);
 
         pci_set_master(pdev);
-        return ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,
-                                 IRQF_SHARED, &svia_sht);
+        if (board_id == vt6421)
+                return ata_host_activate(host, pdev->irq, vt6421_interrupt,
+                                         IRQF_SHARED, &svia_sht);
+        else
+                return ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,
+                                         IRQF_SHARED, &svia_sht);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int svia_pci_device_resume(struct pci_dev *pdev)
+{
+        struct ata_host *host = pci_get_drvdata(pdev);
+        struct svia_priv *hpriv = host->private_data;
+        int rc;
+
+        rc = ata_pci_device_do_resume(pdev);
+        if (rc)
+                return rc;
+
+        if (hpriv->wd_workaround)
+                svia_wd_fix(pdev);
+        ata_host_resume(host);
+
+        return 0;
 }
+#endif
 
 module_pci_driver(svia_pci_driver);
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 94025c5cf797..1547bd93c70b 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -250,6 +250,12 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
         if (error)
                 goto out_destroy_freelist;
 
+        /*
+         * Increase usage count temporarily here so that calling
+         * scsi_autopm_put_host() will trigger runtime idle if there is
+         * nothing else preventing suspending the device.
+         */
+        pm_runtime_get_noresume(&shost->shost_gendev);
         pm_runtime_set_active(&shost->shost_gendev);
         pm_runtime_enable(&shost->shost_gendev);
         device_enable_async_suspend(&shost->shost_gendev);
@@ -290,6 +296,7 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
                 goto out_destroy_host;
 
         scsi_proc_host_add(shost);
+        scsi_autopm_put_host(shost);
         return error;
 
  out_destroy_host:
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
index 459abe1dcc87..b44c1bb687a2 100644
--- a/drivers/scsi/scsi_pm.c
+++ b/drivers/scsi/scsi_pm.c
@@ -139,6 +139,16 @@ static int scsi_bus_resume_common(struct device *dev,
         else
                 fn = NULL;
 
+        /*
+         * Forcibly set runtime PM status of request queue to "active" to
+         * make sure we can again get requests from the queue (see also
+         * blk_pm_peek_request()).
+         *
+         * The resume hook will correct runtime PM status of the disk.
+         */
+        if (scsi_is_sdev_device(dev) && pm_runtime_suspended(dev))
+                blk_set_runtime_active(to_scsi_device(dev)->request_queue);
+
         if (fn) {
                 async_schedule_domain(fn, dev, &scsi_sd_pm_domain);
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 413c84fbc4ed..8a11b69dfc08 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1029,6 +1029,7 @@ extern int blk_pre_runtime_suspend(struct request_queue *q);
 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
 extern void blk_pre_runtime_resume(struct request_queue *q);
 extern void blk_post_runtime_resume(struct request_queue *q, int err);
+extern void blk_set_runtime_active(struct request_queue *q);
 #else
 static inline void blk_pm_runtime_init(struct request_queue *q,
         struct device *dev) {}
@@ -1039,6 +1040,7 @@ static inline int blk_pre_runtime_suspend(struct request_queue *q)
 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
+extern inline void blk_set_runtime_active(struct request_queue *q) {}
 #endif
 
 /*