Merge tag 'platform-drivers-x86-v4.1-1' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86

Pull x86 platform driver updates from Darren Hart:
 "This series includes significant updates to the toshiba_acpi driver
  and the reintroduction of the dell-laptop keyboard backlight additions
  I had to revert previously.  Also included are various fixes for
  typos, warnings, correctness, and minor bugs.

  Specifics:

  dell-laptop:
     - add support for keyboard backlight.

  toshiba_acpi:
     - adaptive keyboard, hotkey, USB sleep and charge, and backlight
       updates.  Update sysfs documentation.

  toshiba_bluetooth:
     - fix enabling/disabling loop on recent devices

  apple-gmux:
     - lock iGP IO to protect from vgaarb changes

  other:
     - Fix typos, clear gcc warnings, clarify pr_* messages, correct
       return types, update MAINTAINERS"

* tag 'platform-drivers-x86-v4.1-1' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86: (25 commits)
  toshiba_acpi: Do not register vendor backlight when acpi_video bl is available
  MAINTAINERS: Add me on list of Dell laptop drivers
  platform: x86: dell-laptop: Add support for keyboard backlight
  Documentation/ABI: Update sysfs-driver-toshiba_acpi entry
  toshiba_acpi: Fix pr_* messages from USB Sleep Functions
  toshiba_acpi: Update and fix USB Sleep and Charge modes
  wmi: Use bool function return values of true/false not 1/0
  toshiba_bluetooth: Fix enabling/disabling loop on recent devices
  toshiba_bluetooth: Clean up *_add function and disable BT device at removal
  toshiba_bluetooth: Add three new functions to the driver
  toshiba_acpi: Fix the enabling of the Special Functions
  toshiba_acpi: Use the Hotkey Event Type function for keymap choosing
  toshiba_acpi: Add Hotkey Event Type function and definitions
  x86/wmi: delete unused wmi_data_lock mutex causing gcc warning
  apple-gmux: lock iGP IO to protect from vgaarb changes
  MAINTAINERS: Add missing Toshiba devices and add myself as maintainer
  toshiba_acpi: Update events in toshiba_acpi_notify
  intel-oaktrail: Fix trivial typo in comment
  thinkpad_acpi: off by one in adaptive_keyboard_hotkey_notify_hotkey()
  thinkpad_acpi: signedness bugs getting current_mode
  ...

1 files changed, 47 insertions, 1 deletions

diff --git a/drivers/platform/x86/apple-gmux.c b/drivers/platform/x86/apple-gmux.c
index 66d6d22c239c..6808715003f6 100644
--- a/drivers/platform/x86/apple-gmux.c
+++ b/drivers/platform/x86/apple-gmux.c
@@ -22,6 +22,7 @@
 #include <linux/delay.h>
 #include <linux/pci.h>
 #include <linux/vga_switcheroo.h>
+#include <linux/vgaarb.h>
 #include <acpi/video.h>
 #include <asm/io.h>
 
@@ -31,6 +32,7 @@ struct apple_gmux_data {
 	bool indexed;
 	struct mutex index_lock;
 
+	struct pci_dev *pdev;
 	struct backlight_device *bdev;
 
 	/* switcheroo data */
@@ -415,6 +417,23 @@ static int gmux_resume(struct device *dev)
 	return 0;
 }
 
+static struct pci_dev *gmux_get_io_pdev(void)
+{
+	struct pci_dev *pdev = NULL;
+
+	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev))) {
+		u16 cmd;
+
+		pci_read_config_word(pdev, PCI_COMMAND, &cmd);
+		if (!(cmd & PCI_COMMAND_IO))
+			continue;
+
+		return pdev;
+	}
+
+	return NULL;
+}
+
 static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
 {
 	struct apple_gmux_data *gmux_data;
@@ -425,6 +444,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
 	int ret = -ENXIO;
 	acpi_status status;
 	unsigned long long gpe;
+	struct pci_dev *pdev = NULL;
 
 	if (apple_gmux_data)
 		return -EBUSY;
@@ -475,7 +495,7 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
 			ver_minor = (version >> 16) & 0xff;
 			ver_release = (version >> 8) & 0xff;
 		} else {
-			pr_info("gmux device not present\n");
+			pr_info("gmux device not present or IO disabled\n");
 			ret = -ENODEV;
 			goto err_release;
 		}
@@ -483,6 +503,23 @@ static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
 	pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor,
 		ver_release, (gmux_data->indexed ? "indexed" : "classic"));
 
+	/*
+	 * Apple systems with gmux are EFI based and normally don't use
+	 * VGA. In addition changing IO+MEM ownership between IGP and dGPU
+	 * disables IO/MEM used for backlight control on some systems.
+	 * Lock IO+MEM to GPU with active IO to prevent switch.
+	 */
+	pdev = gmux_get_io_pdev();
+	if (pdev && vga_tryget(pdev,
+			       VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM)) {
+		pr_err("IO+MEM vgaarb-locking for PCI:%s failed\n",
+			pci_name(pdev));
+		ret = -EBUSY;
+		goto err_release;
+	} else if (pdev)
+		pr_info("locked IO for PCI:%s\n", pci_name(pdev));
+	gmux_data->pdev = pdev;
+
 	memset(&props, 0, sizeof(props));
 	props.type = BACKLIGHT_PLATFORM;
 	props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
@@ -574,6 +611,10 @@ err_enable_gpe:
 err_notify:
 	backlight_device_unregister(bdev);
 err_release:
+	if (gmux_data->pdev)
+		vga_put(gmux_data->pdev,
+			VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM);
+	pci_dev_put(pdev);
 	release_region(gmux_data->iostart, gmux_data->iolen);
 err_free:
 	kfree(gmux_data);
@@ -593,6 +634,11 @@ static void gmux_remove(struct pnp_dev *pnp)
 					   &gmux_notify_handler);
 	}
 
+	if (gmux_data->pdev) {
+		vga_put(gmux_data->pdev,
+			VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM);
+		pci_dev_put(gmux_data->pdev);
+	}
 	backlight_device_unregister(gmux_data->bdev);
 
 	release_region(gmux_data->iostart, gmux_data->iolen);