1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c
new file mode 100644
index 000000000..876ccc620
--- /dev/null
+++ b/drivers/pci/hotplug/acpi_pcihp.c
@@ -0,0 +1,227 @@
+/*
+ * Common ACPI functions for hot plug platforms
+ *
+ * Copyright (C) 2006 Intel Corporation
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Send feedback to <kristen.c.accardi@intel.com>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/pci_hotplug.h>
+#include <linux/acpi.h>
+#include <linux/pci-acpi.h>
+#include <linux/slab.h>
+
+#define MY_NAME	"acpi_pcihp"
+
+#define dbg(fmt, arg...) do { if (debug_acpi) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __func__ , ## arg); } while (0)
+#define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
+#define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
+#define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg)
+
+#define	METHOD_NAME__SUN	"_SUN"
+#define	METHOD_NAME_OSHP	"OSHP"
+
+static bool debug_acpi;
+
+/* acpi_run_oshp - get control of hotplug from the firmware
+ *
+ * @handle - the handle of the hotplug controller.
+ */
+static acpi_status acpi_run_oshp(acpi_handle handle)
+{
+	acpi_status		status;
+	struct acpi_buffer	string = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
+
+	/* run OSHP */
+	status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
+	if (ACPI_FAILURE(status))
+		if (status != AE_NOT_FOUND)
+			printk(KERN_ERR "%s:%s OSHP fails=0x%x\n",
+			       __func__, (char *)string.pointer, status);
+		else
+			dbg("%s:%s OSHP not found\n",
+			    __func__, (char *)string.pointer);
+	else
+		pr_debug("%s:%s OSHP passes\n", __func__,
+			(char *)string.pointer);
+
+	kfree(string.pointer);
+	return status;
+}
+
+/**
+ * acpi_get_hp_hw_control_from_firmware
+ * @dev: the pci_dev of the bridge that has a hotplug controller
+ * @flags: requested control bits for _OSC
+ *
+ * Attempt to take hotplug control from firmware.
+ */
+int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev, u32 flags)
+{
+	acpi_status status;
+	acpi_handle chandle, handle;
+	struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	flags &= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
+	if (!flags) {
+		err("Invalid flags %u specified!\n", flags);
+		return -EINVAL;
+	}
+
+	/*
+	 * Per PCI firmware specification, we should run the ACPI _OSC
+	 * method to get control of hotplug hardware before using it. If
+	 * an _OSC is missing, we look for an OSHP to do the same thing.
+	 * To handle different BIOS behavior, we look for _OSC on a root
+	 * bridge preferentially (according to PCI fw spec). Later for
+	 * OSHP within the scope of the hotplug controller and its parents,
+	 * up to the host bridge under which this controller exists.
+	 */
+	handle = acpi_find_root_bridge_handle(pdev);
+	if (handle) {
+		acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
+		dbg("Trying to get hotplug control for %s\n",
+				(char *)string.pointer);
+		status = acpi_pci_osc_control_set(handle, &flags, flags);
+		if (ACPI_SUCCESS(status))
+			goto got_one;
+		if (status == AE_SUPPORT)
+			goto no_control;
+		kfree(string.pointer);
+		string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL };
+	}
+
+	handle = ACPI_HANDLE(&pdev->dev);
+	if (!handle) {
+		/*
+		 * This hotplug controller was not listed in the ACPI name
+		 * space at all. Try to get acpi handle of parent pci bus.
+		 */
+		struct pci_bus *pbus;
+		for (pbus = pdev->bus; pbus; pbus = pbus->parent) {
+			handle = acpi_pci_get_bridge_handle(pbus);
+			if (handle)
+				break;
+		}
+	}
+
+	while (handle) {
+		acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
+		dbg("Trying to get hotplug control for %s \n",
+		    (char *)string.pointer);
+		status = acpi_run_oshp(handle);
+		if (ACPI_SUCCESS(status))
+			goto got_one;
+		if (acpi_is_root_bridge(handle))
+			break;
+		chandle = handle;
+		status = acpi_get_parent(chandle, &handle);
+		if (ACPI_FAILURE(status))
+			break;
+	}
+no_control:
+	dbg("Cannot get control of hotplug hardware for pci %s\n",
+	    pci_name(pdev));
+	kfree(string.pointer);
+	return -ENODEV;
+got_one:
+	dbg("Gained control for hotplug HW for pci %s (%s)\n",
+	    pci_name(pdev), (char *)string.pointer);
+	kfree(string.pointer);
+	return 0;
+}
+EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);
+
+static int pcihp_is_ejectable(acpi_handle handle)
+{
+	acpi_status status;
+	unsigned long long removable;
+	if (!acpi_has_method(handle, "_ADR"))
+		return 0;
+	if (acpi_has_method(handle, "_EJ0"))
+		return 1;
+	status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
+	if (ACPI_SUCCESS(status) && removable)
+		return 1;
+	return 0;
+}
+
+/**
+ * acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot
+ * @pbus: the PCI bus of the PCI slot corresponding to 'handle'
+ * @handle: ACPI handle to check
+ *
+ * Return 1 if handle is ejectable PCI slot, 0 otherwise.
+ */
+int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
+{
+	acpi_handle bridge_handle, parent_handle;
+
+	bridge_handle = acpi_pci_get_bridge_handle(pbus);
+	if (!bridge_handle)
+		return 0;
+	if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle))))
+		return 0;
+	if (bridge_handle != parent_handle)
+		return 0;
+	return pcihp_is_ejectable(handle);
+}
+EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable);
+
+static acpi_status
+check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+	int *found = (int *)context;
+	if (pcihp_is_ejectable(handle)) {
+		*found = 1;
+		return AE_CTRL_TERMINATE;
+	}
+	return AE_OK;
+}
+
+/**
+ * acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots
+ * @handle - handle of the PCI bus to scan
+ *
+ * Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise.
+ */
+int acpi_pci_detect_ejectable(acpi_handle handle)
+{
+	int found = 0;
+
+	if (!handle)
+		return found;
+
+	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+			    check_hotplug, NULL, (void *)&found, NULL);
+	return found;
+}
+EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable);
+
+module_param(debug_acpi, bool, 0644);
+MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not");