bbswitch_dev: disable runtime PM on removal

Call pm_runtime_forbid() to balance it with pm_runtime_allow(), this
ensures that the runtime usage counter before loading and after
unloading match.

README.md

@@ -59,45 +59,6 @@ To uninstall it, run:
 
     # make -f Makefile.dkms uninstall
 
-Lenovo IdeaPad Y470/Y570 and Toshiba SATELLITE P870
----------------------------------------------------
-[This kernel bug](https://bugzilla.kernel.org/show_bug.cgi?id=42696) is fixed in
-Linux 3.9-rc1 and Linux 3.8.5 which obsoletes this hack. Linux 3.7 is
-incompatible with this hack (and already EOL'd, so a backport fix won't be made
-available).
-
-In kernel version 3.6 and older, you need to apply an ugly hack on these laptops
-to make bbswitch and the
-driver (both nouveau and nvidia) work. For now I have decided not to put the
-hack in the bbswitch module since it is a very ugly hack that is comparable to
-writing a maximum allowable speed of 130 km/h on a traffic sign for a road
-where 120 km/h is allowed just because the radar gun does not work properly.
-
-The module has been tested on a Lenovo IdeaPad Y570 running an up-to-date
-version of Ubuntu 11.10 Oneiric (64-bit) with Bumblebee 3.0 (3.0-1~oneiricppa2)
-installed using the nvidia driver.
-
-To make use of it, use the `hack-lenovo` branch. An example using DKMS:
-
-    $ git clone git://github.com/Bumblebee-Project/bbswitch.git -b hack-lenovo
-    $ cd bbswitch
-    $ mkdir /usr/src/acpi-handle-hack-0.0.2
-    # cp Makefile acpi-handle-hack.c /usr/src/acpi-handle-hack-0.0.2
-    # cp dkms/acpi-handle-hack.conf /usr/src/acpi-handle-hack-0.0.2/dkms.conf
-    # dkms install -m acpi-handle-hack -v 0.0.2
-If everything goes well, you now need to get the hack loaded on boot. On
-Ubuntu and Debian, this can be done with:
-
-    echo acpi-handle-hack | sudo tee -a /etc/modules
-    sudo update-initramfs -u
-For other systems, adopt the instructions from the *Disable card on boot*
-section below. Please do not copy these instructions to blogs/forums/whatever
-without warning that the method is a hack (you can refer to the metaphore above)
-and that it may crash the machine if incorrectly applied. To apply these
-changes, you have to reboot (technically, unloading nvidia/nouveau, bbswitch and
-stopping bumblebeed, `modprobe acpi-handle-hack` and starting bumblebeed should
-work as well, but saying reboot is shorter)
-
 Usage
 -----
 
@@ -204,3 +165,9 @@ issues on this module in the issue tracker and provide the following details:
 
 Upload the generated tarball on the above Launchpad URL and provide a link to
 the comment containing your report.
+
+TODO
+----
+With the new PCI device approach, if load_state=0, then starting bumblebeed will
+unload bbswitch. Fix Bumblebee not to unload the module when the PM method is
+bbswitch and the loaded module is bbswitch.

acpi-handle-hack.c

@@ -1,134 +0,0 @@
-/**
- * Very ugly hack to work around a wrongly detected ACPI handle, see
- * https://bugzilla.kernel.org/show_bug.cgi?id=42696
- * https://bugzilla.kernel.org/show_bug.cgi?id=60829
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/pci.h>
-#include <linux/acpi.h>
-#include <linux/dmi.h>
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Dirty ACPI handle hack for Lenovo IdeaPad Y[45]70");
-MODULE_AUTHOR("Peter Lekensteyn <lekensteyn@gmail.com>");
-MODULE_VERSION("0.0.2");
-
-static struct pci_dev *dis_dev;
-static acpi_handle orig_handle;
-
-/**
- * Returns true if the system needs an ACPI handle hack
- */
-static bool __init need_acpi_handle_hack(void) {
-	return dmi_match(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y470             ")
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y480")	
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y570             ")
-		|| dmi_match(DMI_PRODUCT_VERSION, "LENOVO IDEAPAD Y570 ") /* sys-product-name: PIQY0 */
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Y580")
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo IdeaPad U510")
-		|| dmi_match(DMI_PRODUCT_VERSION, "PSPLBE-01V00HFR") /* TOSHIBA SATELLITE P870 */
-		|| dmi_match(DMI_PRODUCT_VERSION, "PSPLBA-02300S") /* TOSHIBA Satellite P870 */
-		|| dmi_match(DMI_PRODUCT_VERSION, "PSPLFE-00E009FR") /* TOSHIBA Satellite P870 */
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo G580")
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo G780")
-		|| dmi_match(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Z500")
-		|| (dmi_match(DMI_SYS_VENDOR, "LENOVO") && dmi_match(DMI_PRODUCT_NAME, "PIQY0")) /* Lenovo IdeaPad Y570 */
-		|| dmi_match(DMI_PRODUCT_NAME, "Aspire V5-573G")
-		|| dmi_match(DMI_PRODUCT_NAME, "Aspire V5-573PG")
-		;
-}
-
-static struct pci_dev __init *get_discrete_device(void) {
-	struct pci_dev *pdev = NULL;
-	while ((pdev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, pdev)) != NULL) {
-		int pci_class = pdev->class >> 8;
-
-		if (pci_class != PCI_CLASS_DISPLAY_VGA &&
-			pci_class != PCI_CLASS_DISPLAY_3D)
-			continue;
-
-		if (pdev->vendor != PCI_VENDOR_ID_INTEL) {
-			return pdev;
-		}
-	}
-	return NULL;
-}
-
-/**
- * Very ugly hack to set the ACPI handle, do not use this as exemplary code!
- */
-static void dev_set_acpi_handle(struct pci_dev *pdev, acpi_handle handle) {
-#ifdef ACPI_HANDLE_SET
-	ACPI_HANDLE_SET(&pdev->dev, handle);
-#else
-	/* for Linux 3.7 and earlier */
-	pdev->dev.archdata.acpi_handle = handle;
-#endif
-}
-
-static int __init hack_apply(void) {
-	acpi_handle tmp_handle, new_handle;
-	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
-	if (!need_acpi_handle_hack()) {
-		pr_err("Machine does not need ACPI handle hack\n");
-		return -ENODEV;
-	}
-	dis_dev = get_discrete_device();
-	if (!dis_dev) {
-		pr_err("No discrete video card found\n");
-		return -ENODEV;
-	}
-
-#ifdef ACPI_HANDLE
-	/* since Linux 3.8 */
-	orig_handle = ACPI_HANDLE(&dis_dev->dev);
-#else
-	/* removed since Linux 3.13 */
-	orig_handle = DEVICE_ACPI_HANDLE(&dis_dev->dev);
-#endif
-	if (!orig_handle) {
-		pr_err("No ACPI handle found for discrete video card\n");
-		goto free_dev;
-	}
-	if (ACPI_FAILURE(acpi_get_name(orig_handle, ACPI_SINGLE_NAME, &buf))) {
-		pr_err("Could not acquire name for discrete video card\n");
-		goto free_dev;
-	}
-	if (strcmp((char *)buf.pointer, "PEGP") == 0) {
-		pr_err("Handle has already been changed to PEGP\n");
-		goto free_name;
-	}
-	/* \_SB.PCI0.PEG0.VGA_ -> \_SB.PCI0.PEG0.PEGP */
-	if (ACPI_FAILURE(acpi_get_parent(orig_handle, &tmp_handle))) {
-		pr_err("No parent device found for %s\n", (char *)buf.pointer);
-		goto free_name;
-	}
-	if (ACPI_FAILURE(acpi_get_handle(tmp_handle, "PEGP", &new_handle))) {
-		pr_err("No PEGP handle found on %s\n", (char *)buf.pointer);
-		goto free_name;
-	}
-	pr_info("Setting new ACPI handle for discrete video card\n");
-	dev_set_acpi_handle(dis_dev, new_handle);
-	kfree(buf.pointer);
-	pci_dev_put(dis_dev);
-	return 0;
-free_name:
-	kfree(buf.pointer);
-free_dev:
-	pci_dev_put(dis_dev);
-	return -ENODEV;
-}
-
-static void __exit hack_undo(void) {
-	if (orig_handle) {
-		pr_info("Restoring original ACPI handle for discrete"
-			" video card\n");
-		dev_set_acpi_handle(dis_dev, orig_handle);
-	}
-}
-
-module_init(hack_apply);
-module_exit(hack_undo);

bbswitch.c

@@ -8,6 +8,16 @@
  * # echo ON > /proc/acpi/bbswitch
  * Get status
  * # cat /proc/acpi/bbswitch
+ *
+ * Note: only one PCI driver (bbswitch, nouveau, etc.) can bind to a PCI device.
+ * When turning a device OFF, bbswitch tries to bind itself to the PCI device.
+ * When turning a device ON, bbswitch unbinds a device (if it was bound) before
+ * returning from the write.
+ *
+ * TODO is this true?
+ * The new dual module approach is used to allow for backwards compatibility,
+ * Bumblebee unloads any driver that is loaded for a device, that would however
+ * result in unloading the main bbswitch module.
  */
 /*
  *  Copyright (C) 2011-2013 Bumblebee Project
@@ -197,6 +207,26 @@ static int bbswitch_optimus_dsm(void) {
     return 0;
 }
 
+// Windows 8/8.1/10 do not use DSM to put the device in D3cold state,
+// instead it disables power resources on the parent PCIe port device.
+static bool has_pr3_support(void) {
+    acpi_handle parent_handle;
+    struct acpi_device *ad = NULL;
+
+    if (ACPI_FAILURE(acpi_get_parent(dis_handle, &parent_handle))) {
+        pr_warn("Failed to obtain the parent device\n");
+        return false;
+    }
+
+    acpi_bus_get_device(parent_handle, &ad);
+    if (!ad) {
+        pr_warn("Failed to obtain an ACPI device for handle\n");
+        return false;
+    }
+
+    return ad->power.flags.power_resources;
+}
+
 static int bbswitch_acpi_off(void) {
     if (dsm_type == DSM_TYPE_NVIDIA) {
         char args[] = {2, 0, 0, 0};
@@ -436,7 +466,9 @@ static int __init bbswitch_init(void) {
         return -ENODEV;
     }
 
-    if (!skip_optimus_dsm &&
+    if (has_pr3_support()) {
+        pr_info("skipping _DSM as _PR3 support is detected\n");
+    } else if (!skip_optimus_dsm &&
             has_dsm_func(acpi_optimus_dsm_muid, 0x100, 0x1A)) {
         dsm_type = DSM_TYPE_OPTIMUS;
         pr_info("detected an Optimus _DSM function\n");

bbswitch_dev.c

@@ -0,0 +1,100 @@
+/*
+ * TODO merge into main bbswitch module.
+ * TODO on ON call device_release_driver
+ * TODO how to bind to a specific device from kernel space? Can't use
+ *      driver_probe_device (https://lkml.org/lkml/2014/2/14/628). Maybe use
+ *      driver_override or new_id/bind/remove_id from userspace?
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/delay.h>
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Toggle the discrete graphics card (PCI driver)");
+MODULE_AUTHOR("Peter Wu <peter@lekensteyn.nl>");
+
+static int bbswitch_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+    /* TODO how to discover devices? */
+    /* Prevent kernel from detaching the PCI device for some devices that
+     * generate hotplug events. The graphics card is typically not physically
+     * removable. */
+    pci_ignore_hotplug(dev);
+
+    pm_runtime_set_active(&dev->dev); /* clear any errors */
+    /* Use autosuspend to avoid lspci waking up the device multiple times. */
+    pm_runtime_set_autosuspend_delay(&dev->dev, 2000);
+    pm_runtime_use_autosuspend(&dev->dev);
+    pm_runtime_allow(&dev->dev);
+    pm_runtime_put_autosuspend(&dev->dev);
+    return 0;
+}
+
+static void bbswitch_pci_remove(struct pci_dev *dev)
+{
+    pm_runtime_get_noresume(&dev->dev);
+    pm_runtime_dont_use_autosuspend(&dev->dev);
+    pm_runtime_forbid(&dev->dev);
+}
+
+static int bbswitch_runtime_suspend(struct device *dev) {
+    struct pci_dev *pdev = to_pci_dev(dev);
+
+    pr_info("disabling discrete graphics\n");
+
+    /* TODO if _PR3 is not supported, call Optimus DSM here. */
+    /* TODO for v1 Optimus, call DSM here. */
+
+    /* Save state now that the device is still awake, makes PCI layer happy */
+    pci_save_state(pdev);
+    /* TODO if _PR3 is supported, should this be PCI_D3hot? */
+    pci_set_power_state(pdev, PCI_D3cold);
+    return 0;
+}
+
+static int bbswitch_runtime_resume(struct device *dev) {
+    pr_info("enabling discrete graphics\n");
+
+    /* TODO for v1 Optimus, call DSM here. */
+    /* Nothing to do for Optimus, the PCI layer already moved into D0 state. */
+    return 0;
+}
+
+static struct dev_pm_ops bbswitch_pm_ops = {
+    .runtime_suspend = bbswitch_runtime_suspend,
+    .runtime_resume = bbswitch_runtime_resume,
+    /* No runtime_idle callback, the default zero delay is sufficient. */
+};
+
+static struct pci_driver bbswitch_pci_driver = {
+    .name = KBUILD_MODNAME,
+    .id_table = NULL, /* will be added dynamically */
+    .probe  = bbswitch_pci_probe,
+    .remove = bbswitch_pci_remove,
+    .driver.pm = &bbswitch_pm_ops,
+};
+
+static int __init bbswitch_dev_init(void) {
+    int ret;
+
+    ret = pci_register_driver(&bbswitch_pci_driver);
+#if 0
+    ret = pci_add_dynid(&bbswitch_pci_driver, PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
+            PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16, 0xff0000);
+#endif
+
+    return ret;
+}
+
+static void __exit bbswitch_dev_exit(void) {
+    pci_unregister_driver(&bbswitch_pci_driver);
+}
+
+module_init(bbswitch_dev_init);
+module_exit(bbswitch_dev_exit);
+
+/* vim: set sw=4 ts=4 et: */

dkms/acpi-handle-hack.conf

@@ -1,7 +0,0 @@
-PACKAGE_NAME="acpi-handle-hack"
-PACKAGE_VERSION="0.0.2"
-MAKE[0]="make KVERSION=$kernelver modname=acpi-handle-hack"
-CLEAN="make clean"
-BUILT_MODULE_NAME[0]="acpi-handle-hack"
-DEST_MODULE_LOCATION[0]="/kernel/drivers/acpi"
-AUTOINSTALL="yes"