15 files changed, 148 insertions, 240 deletions

diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt
index f732a8321e8a..8cc17ca71813 100644
--- a/Documentation/power/swsusp.txt
+++ b/Documentation/power/swsusp.txt
@@ -410,8 +410,17 @@ Documentation/usb/persist.txt.
 
 Q: Can I suspend-to-disk using a swap partition under LVM?
 
-A: No. You can suspend successfully, but you'll not be able to
-resume. uswsusp should be able to work with LVM. See suspend.sf.net.
+A: Yes and No.  You can suspend successfully, but the kernel will not be able
+to resume on its own.  You need an initramfs that can recognize the resume
+situation, activate the logical volume containing the swap volume (but not
+touch any filesystems!), and eventually call
+
+echo -n "$major:$minor" > /sys/power/resume
+
+where $major and $minor are the respective major and minor device numbers of
+the swap volume.
+
+uswsusp works with LVM, too.  See http://suspend.sourceforge.net/
 
 Q: I upgraded the kernel from 2.6.15 to 2.6.16. Both kernels were
 compiled with the similar configuration files. Anyway I found that
diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 569ee090343f..46b58abb08c5 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -352,13 +352,16 @@ static int acpi_lpss_create_device(struct acpi_device *adev,
                                 pdata->mmio_size = resource_size(rentry->res);
                         pdata->mmio_base = ioremap(rentry->res->start,
                                                    pdata->mmio_size);
-                        if (!pdata->mmio_base)
-                                goto err_out;
                         break;
                 }
 
         acpi_dev_free_resource_list(&resource_list);
 
+        if (!pdata->mmio_base) {
+                ret = -ENOMEM;
+                goto err_out;
+        }
+
         pdata->dev_desc = dev_desc;
 
         if (dev_desc->setup)
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index c262e4acd68d..3b8963f21b36 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -175,10 +175,14 @@ static void __init acpi_request_region (struct acpi_generic_address *gas,
         if (!addr || !length)
                 return;
 
-        acpi_reserve_region(addr, length, gas->space_id, 0, desc);
+        /* Resources are never freed */
+        if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
+                request_region(addr, length, desc);
+        else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
+                request_mem_region(addr, length, desc);
 }
 
-static void __init acpi_reserve_resources(void)
+static int __init acpi_reserve_resources(void)
 {
         acpi_request_region(&acpi_gbl_FADT.xpm1a_event_block, acpi_gbl_FADT.pm1_event_length,
                 "ACPI PM1a_EVT_BLK");
@@ -207,7 +211,10 @@ static void __init acpi_reserve_resources(void)
         if (!(acpi_gbl_FADT.gpe1_block_length & 0x1))
                 acpi_request_region(&acpi_gbl_FADT.xgpe1_block,
                                acpi_gbl_FADT.gpe1_block_length, "ACPI GPE1_BLK");
+
+        return 0;
 }
+fs_initcall_sync(acpi_reserve_resources);
 
 void acpi_os_printf(const char *fmt, ...)
 {
@@ -1862,7 +1869,6 @@ acpi_status __init acpi_os_initialize(void)
 
 acpi_status __init acpi_os_initialize1(void)
 {
-        acpi_reserve_resources();
         kacpid_wq = alloc_workqueue("kacpid", 0, 1);
         kacpi_notify_wq = alloc_workqueue("kacpi_notify", 0, 1);
         kacpi_hotplug_wq = alloc_ordered_workqueue("kacpi_hotplug", 0);
diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 10561ce16ed1..8244f013f210 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -26,7 +26,6 @@
 #include <linux/device.h>
 #include <linux/export.h>
 #include <linux/ioport.h>
-#include <linux/list.h>
 #include <linux/slab.h>
 
 #ifdef CONFIG_X86
@@ -622,164 +621,3 @@ int acpi_dev_filter_resource_type(struct acpi_resource *ares,
         return (type & types) ? 0 : 1;
 }
 EXPORT_SYMBOL_GPL(acpi_dev_filter_resource_type);
-
-struct reserved_region {
-        struct list_head node;
-        u64 start;
-        u64 end;
-};
-
-static LIST_HEAD(reserved_io_regions);
-static LIST_HEAD(reserved_mem_regions);
-
-static int request_range(u64 start, u64 end, u8 space_id, unsigned long flags,
-                         char *desc)
-{
-        unsigned int length = end - start + 1;
-        struct resource *res;
-
-        res = space_id == ACPI_ADR_SPACE_SYSTEM_IO ?
-                request_region(start, length, desc) :
-                request_mem_region(start, length, desc);
-        if (!res)
-                return -EIO;
-
-        res->flags &= ~flags;
-        return 0;
-}
-
-static int add_region_before(u64 start, u64 end, u8 space_id,
-                             unsigned long flags, char *desc,
-                             struct list_head *head)
-{
-        struct reserved_region *reg;
-        int error;
-
-        reg = kmalloc(sizeof(*reg), GFP_KERNEL);
-        if (!reg)
-                return -ENOMEM;
-
-        error = request_range(start, end, space_id, flags, desc);
-        if (error) {
-                kfree(reg);
-                return error;
-        }
-
-        reg->start = start;
-        reg->end = end;
-        list_add_tail(&reg->node, head);
-        return 0;
-}
-
-/**
- * acpi_reserve_region - Reserve an I/O or memory region as a system resource.
- * @start: Starting address of the region.
- * @length: Length of the region.
- * @space_id: Identifier of address space to reserve the region from.
- * @flags: Resource flags to clear for the region after requesting it.
- * @desc: Region description (for messages).
- *
- * Reserve an I/O or memory region as a system resource to prevent others from
- * using it.  If the new region overlaps with one of the regions (in the given
- * address space) already reserved by this routine, only the non-overlapping
- * parts of it will be reserved.
- *
- * Returned is either 0 (success) or a negative error code indicating a resource
- * reservation problem.  It is the code of the first encountered error, but the
- * routine doesn't abort until it has attempted to request all of the parts of
- * the new region that don't overlap with other regions reserved previously.
- *
- * The resources requested by this routine are never released.
- */
-int acpi_reserve_region(u64 start, unsigned int length, u8 space_id,
-                        unsigned long flags, char *desc)
-{
-        struct list_head *regions;
-        struct reserved_region *reg;
-        u64 end = start + length - 1;
-        int ret = 0, error = 0;
-
-        if (space_id == ACPI_ADR_SPACE_SYSTEM_IO)
-                regions = &reserved_io_regions;
-        else if (space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
-                regions = &reserved_mem_regions;
-        else
-                return -EINVAL;
-
-        if (list_empty(regions))
-                return add_region_before(start, end, space_id, flags, desc, regions);
-
-        list_for_each_entry(reg, regions, node)
-                if (reg->start == end + 1) {
-                        /* The new region can be prepended to this one. */
-                        ret = request_range(start, end, space_id, flags, desc);
-                        if (!ret)
-                                reg->start = start;
-
-                        return ret;
-                } else if (reg->start > end) {
-                        /* No overlap.  Add the new region here and get out. */
-                        return add_region_before(start, end, space_id, flags,
-                                                 desc, &reg->node);
-                } else if (reg->end == start - 1) {
-                        goto combine;
-                } else if (reg->end >= start) {
-                        goto overlap;
-                }
-
-        /* The new region goes after the last existing one. */
-        return add_region_before(start, end, space_id, flags, desc, regions);
-
- overlap:
-        /*
-         * The new region overlaps an existing one.
-         *
-         * The head part of the new region immediately preceding the existing
-         * overlapping one can be combined with it right away.
-         */
-        if (reg->start > start) {
-                error = request_range(start, reg->start - 1, space_id, flags, desc);
-                if (error)
-                        ret = error;
-                else
-                        reg->start = start;
-        }
-
- combine:
-        /*
-         * The new region is adjacent to an existing one.  If it extends beyond
-         * that region all the way to the next one, it is possible to combine
-         * all three of them.
-         */
-        while (reg->end < end) {
-                struct reserved_region *next = NULL;
-                u64 a = reg->end + 1, b = end;
-
-                if (!list_is_last(&reg->node, regions)) {
-                        next = list_next_entry(reg, node);
-                        if (next->start <= end)
-                                b = next->start - 1;
-                }
-                error = request_range(a, b, space_id, flags, desc);
-                if (!error) {
-                        if (next && next->start == b + 1) {
-                                reg->end = next->end;
-                                list_del(&next->node);
-                                kfree(next);
-                        } else {
-                                reg->end = end;
-                                break;
-                        }
-                } else if (next) {
-                        if (!ret)
-                                ret = error;
-
-                        reg = next;
-                } else {
-                        break;
-                }
-        }
-
-        return ret ? ret : error;
-}
-EXPORT_SYMBOL_GPL(acpi_reserve_region);
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 2649a068671d..ec256352f423 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1019,6 +1019,29 @@ static bool acpi_of_match_device(struct acpi_device *adev,
         return false;
 }
 
+static bool __acpi_match_device_cls(const struct acpi_device_id *id,
+                                    struct acpi_hardware_id *hwid)
+{
+        int i, msk, byte_shift;
+        char buf[3];
+
+        if (!id->cls)
+                return false;
+
+        /* Apply class-code bitmask, before checking each class-code byte */
+        for (i = 1; i <= 3; i++) {
+                byte_shift = 8 * (3 - i);
+                msk = (id->cls_msk >> byte_shift) & 0xFF;
+                if (!msk)
+                        continue;
+
+                sprintf(buf, "%02x", (id->cls >> byte_shift) & msk);
+                if (strncmp(buf, &hwid->id[(i - 1) * 2], 2))
+                        return false;
+        }
+        return true;
+}
+
 static const struct acpi_device_id *__acpi_match_device(
         struct acpi_device *device,
         const struct acpi_device_id *ids,
@@ -1036,9 +1059,12 @@ static const struct acpi_device_id *__acpi_match_device(
 
         list_for_each_entry(hwid, &device->pnp.ids, list) {
                 /* First, check the ACPI/PNP IDs provided by the caller. */
-                for (id = ids; id->id[0]; id++)
-                        if (!strcmp((char *) id->id, hwid->id))
+                for (id = ids; id->id[0] || id->cls; id++) {
+                        if (id->id[0] && !strcmp((char *) id->id, hwid->id))
                                 return id;
+                        else if (id->cls && __acpi_match_device_cls(id, hwid))
+                                return id;
+                }
 
                 /*
                  * Next, check ACPI_DT_NAMESPACE_HID and try to match the
@@ -2101,6 +2127,8 @@ static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
                 if (info->valid & ACPI_VALID_UID)
                         pnp->unique_id = kstrdup(info->unique_id.string,
                                                         GFP_KERNEL);
+                if (info->valid & ACPI_VALID_CLS)
+                        acpi_add_id(pnp, info->class_code.string);
 
                 kfree(info);
 
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 6d17a3b65ef7..15e40ee62a94 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -48,7 +48,7 @@ config ATA_VERBOSE_ERROR
 
 config ATA_ACPI
         bool "ATA ACPI Support"
-        depends on ACPI && PCI
+        depends on ACPI
         default y
         help
           This option adds support for ATA-related ACPI objects.
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 614c78f510f0..1befb114c384 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -20,6 +20,8 @@
 #include <linux/platform_device.h>
 #include <linux/libata.h>
 #include <linux/ahci_platform.h>
+#include <linux/acpi.h>
+#include <linux/pci_ids.h>
 #include "ahci.h"
 
 #define DRV_NAME "ahci"
@@ -79,12 +81,19 @@ static const struct of_device_id ahci_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, ahci_of_match);
 
+static const struct acpi_device_id ahci_acpi_match[] = {
+        { ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) },
+        {},
+};
+MODULE_DEVICE_TABLE(acpi, ahci_acpi_match);
+
 static struct platform_driver ahci_driver = {
         .probe = ahci_probe,
         .remove = ata_platform_remove_one,
         .driver = {
                 .name = DRV_NAME,
                 .of_match_table = ahci_of_match,
+                .acpi_match_table = ahci_acpi_match,
                 .pm = &ahci_pm_ops,
         },
 };
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index cdd547bd67df..0ee43c1056e0 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -6,6 +6,7 @@
  * This file is released under the GPLv2.
  */
 
+#include <linux/delay.h>
 #include <linux/kernel.h>
 #include <linux/io.h>
 #include <linux/platform_device.h>
@@ -19,6 +20,8 @@
 #include <linux/suspend.h>
 #include <linux/export.h>
 
+#define GENPD_RETRY_MAX_MS      250             /* Approximate */
+
 #define GENPD_DEV_CALLBACK(genpd, type, callback, dev)          \
 ({                                                              \
         type (*__routine)(struct device *__d);                  \
@@ -2131,6 +2134,7 @@ EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
 static void genpd_dev_pm_detach(struct device *dev, bool power_off)
 {
         struct generic_pm_domain *pd;
+        unsigned int i;
         int ret = 0;
 
         pd = pm_genpd_lookup_dev(dev);
@@ -2139,10 +2143,12 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
 
         dev_dbg(dev, "removing from PM domain %s\n", pd->name);
 
-        while (1) {
+        for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
                 ret = pm_genpd_remove_device(pd, dev);
                 if (ret != -EAGAIN)
                         break;
+
+                mdelay(i);
                 cond_resched();
         }
 
@@ -2183,6 +2189,7 @@ int genpd_dev_pm_attach(struct device *dev)
 {
         struct of_phandle_args pd_args;
         struct generic_pm_domain *pd;
+        unsigned int i;
         int ret;
 
         if (!dev->of_node)
@@ -2218,10 +2225,12 @@ int genpd_dev_pm_attach(struct device *dev)
 
         dev_dbg(dev, "adding to PM domain %s\n", pd->name);
 
-        while (1) {
+        for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
                 ret = pm_genpd_add_device(pd, dev);
                 if (ret != -EAGAIN)
                         break;
+
+                mdelay(i);
                 cond_resched();
         }
 
diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c
index 7470004ca810..eb6e67451dec 100644
--- a/drivers/base/power/wakeirq.c
+++ b/drivers/base/power/wakeirq.c
@@ -45,14 +45,12 @@ static int dev_pm_attach_wake_irq(struct device *dev, int irq,
                 return -EEXIST;
         }
 
-        dev->power.wakeirq = wirq;
-        spin_unlock_irqrestore(&dev->power.lock, flags);
-
         err = device_wakeup_attach_irq(dev, wirq);
-        if (err)
-                return err;
+        if (!err)
+                dev->power.wakeirq = wirq;
 
-        return 0;
+        spin_unlock_irqrestore(&dev->power.lock, flags);
+        return err;
 }
 
 /**
@@ -105,10 +103,10 @@ void dev_pm_clear_wake_irq(struct device *dev)
                 return;
 
         spin_lock_irqsave(&dev->power.lock, flags);
+        device_wakeup_detach_irq(dev);
         dev->power.wakeirq = NULL;
         spin_unlock_irqrestore(&dev->power.lock, flags);
 
-        device_wakeup_detach_irq(dev);
         if (wirq->dedicated_irq)
                 free_irq(wirq->irq, wirq);
         kfree(wirq);
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 40f71603378c..51f15bc15774 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -281,32 +281,25 @@ EXPORT_SYMBOL_GPL(device_wakeup_enable);
  * Attach a device wakeirq to the wakeup source so the device
  * wake IRQ can be configured automatically for suspend and
  * resume.
+ *
+ * Call under the device's power.lock lock.
  */
 int device_wakeup_attach_irq(struct device *dev,
                              struct wake_irq *wakeirq)
 {
         struct wakeup_source *ws;
-        int ret = 0;
 
-        spin_lock_irq(&dev->power.lock);
         ws = dev->power.wakeup;
         if (!ws) {
                 dev_err(dev, "forgot to call call device_init_wakeup?\n");
-                ret = -EINVAL;
-                goto unlock;
+                return -EINVAL;
         }
 
-        if (ws->wakeirq) {
-                ret = -EEXIST;
-                goto unlock;
-        }
+        if (ws->wakeirq)
+                return -EEXIST;
 
         ws->wakeirq = wakeirq;
-
-unlock:
-        spin_unlock_irq(&dev->power.lock);
-
-        return ret;
+        return 0;
 }
 
 /**
@@ -314,20 +307,16 @@ unlock:
  * @dev: Device to handle
  *
  * Removes a device wakeirq from the wakeup source.
+ *
+ * Call under the device's power.lock lock.
  */
 void device_wakeup_detach_irq(struct device *dev)
 {
         struct wakeup_source *ws;
 
-        spin_lock_irq(&dev->power.lock);
         ws = dev->power.wakeup;
-        if (!ws)
-                goto unlock;
-
-        ws->wakeirq = NULL;
-
-unlock:
-        spin_unlock_irq(&dev->power.lock);
+        if (ws)
+                ws->wakeirq = NULL;
 }
 
 /**
diff --git a/drivers/pnp/system.c b/drivers/pnp/system.c
index 515f33882ab8..49c1720df59a 100644
--- a/drivers/pnp/system.c
+++ b/drivers/pnp/system.c
@@ -7,7 +7,6 @@
  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
  */
 
-#include <linux/acpi.h>
 #include <linux/pnp.h>
 #include <linux/device.h>
 #include <linux/init.h>
@@ -23,41 +22,25 @@ static const struct pnp_device_id pnp_dev_table[] = {
         {"", 0}
 };
 
-#ifdef CONFIG_ACPI
-static bool __reserve_range(u64 start, unsigned int length, bool io, char *desc)
-{
-        u8 space_id = io ? ACPI_ADR_SPACE_SYSTEM_IO : ACPI_ADR_SPACE_SYSTEM_MEMORY;
-        return !acpi_reserve_region(start, length, space_id, IORESOURCE_BUSY, desc);
-}
-#else
-static bool __reserve_range(u64 start, unsigned int length, bool io, char *desc)
-{
-        struct resource *res;
-
-        res = io ? request_region(start, length, desc) :
-                request_mem_region(start, length, desc);
-        if (res) {
-                res->flags &= ~IORESOURCE_BUSY;
-                return true;
-        }
-        return false;
-}
-#endif
-
 static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
 {
         char *regionid;
         const char *pnpid = dev_name(&dev->dev);
         resource_size_t start = r->start, end = r->end;
-        bool reserved;
+        struct resource *res;
 
         regionid = kmalloc(16, GFP_KERNEL);
         if (!regionid)
                 return;
 
         snprintf(regionid, 16, "pnp %s", pnpid);
-        reserved = __reserve_range(start, end - start + 1, !!port, regionid);
-        if (!reserved)
+        if (port)
+                res = request_region(start, end - start + 1, regionid);
+        else
+                res = request_mem_region(start, end - start + 1, regionid);
+        if (res)
+                res->flags &= ~IORESOURCE_BUSY;
+        else
                 kfree(regionid);
 
         /*
@@ -66,7 +49,7 @@ static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
          * have double reservations.
          */
         dev_info(&dev->dev, "%pR %s reserved\n", r,
-                 reserved ? "has been" : "could not be");
+                 res ? "has been" : "could not be");
 }
 
 static void reserve_resources_of_dev(struct pnp_dev *dev)
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index c471dfc93b71..d2445fa9999f 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -58,6 +58,19 @@ static inline acpi_handle acpi_device_handle(struct acpi_device *adev)
         acpi_fwnode_handle(adev) : NULL)
 #define ACPI_HANDLE(dev)                acpi_device_handle(ACPI_COMPANION(dev))
 
+/**
+ * ACPI_DEVICE_CLASS - macro used to describe an ACPI device with
+ * the PCI-defined class-code information
+ *
+ * @_cls : the class, subclass, prog-if triple for this device
+ * @_msk : the class mask for this device
+ *
+ * This macro is used to create a struct acpi_device_id that matches a
+ * specific PCI class. The .id and .driver_data fields will be left
+ * initialized with the default value.
+ */
+#define ACPI_DEVICE_CLASS(_cls, _msk)   .cls = (_cls), .cls_msk = (_msk),
+
 static inline bool has_acpi_companion(struct device *dev)
 {
         return is_acpi_node(dev->fwnode);
@@ -309,9 +322,6 @@ int acpi_check_region(resource_size_t start, resource_size_t n,
 
 int acpi_resources_are_enforced(void);
 
-int acpi_reserve_region(u64 start, unsigned int length, u8 space_id,
-                        unsigned long flags, char *desc);
-
 #ifdef CONFIG_HIBERNATION
 void __init acpi_no_s4_hw_signature(void);
 #endif
@@ -446,6 +456,7 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *);
 #define ACPI_COMPANION(dev)             (NULL)
 #define ACPI_COMPANION_SET(dev, adev)   do { } while (0)
 #define ACPI_HANDLE(dev)                (NULL)
+#define ACPI_DEVICE_CLASS(_cls, _msk)   .cls = (0), .cls_msk = (0),
 
 struct fwnode_handle;
 
@@ -507,13 +518,6 @@ static inline int acpi_check_region(resource_size_t start, resource_size_t n,
         return 0;
 }
 
-static inline int acpi_reserve_region(u64 start, unsigned int length,
-                                      u8 space_id, unsigned long flags,
-                                      char *desc)
-{
-        return -ENXIO;
-}
-
 struct acpi_table_header;
 static inline int acpi_table_parse(char *id,
                                 int (*handler)(struct acpi_table_header *))
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 8183d6640ca7..34f25b7bf642 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -189,6 +189,8 @@ struct css_device_id {
 struct acpi_device_id {
         __u8 id[ACPI_ID_LEN];
         kernel_ulong_t driver_data;
+        __u32 cls;
+        __u32 cls_msk;
 };
 
 #define PNP_ID_LEN      8
diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index eff7de1fc82e..e70fcd12eeeb 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -63,6 +63,8 @@ int main(void)
 
         DEVID(acpi_device_id);
         DEVID_FIELD(acpi_device_id, id);
+        DEVID_FIELD(acpi_device_id, cls);
+        DEVID_FIELD(acpi_device_id, cls_msk);
 
         DEVID(pnp_device_id);
         DEVID_FIELD(pnp_device_id, id);
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 84c86f3cd6cd..5f2088209132 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -523,12 +523,40 @@ static int do_serio_entry(const char *filename,
 }
 ADD_TO_DEVTABLE("serio", serio_device_id, do_serio_entry);
 
-/* looks like: "acpi:ACPI0003 or acpi:PNP0C0B" or "acpi:LNXVIDEO" */
+/* looks like: "acpi:ACPI0003" or "acpi:PNP0C0B" or "acpi:LNXVIDEO" or
+ *             "acpi:bbsspp" (bb=base-class, ss=sub-class, pp=prog-if)
+ *
+ * NOTE: Each driver should use one of the following : _HID, _CIDs
+ *       or _CLS. Also, bb, ss, and pp can be substituted with ??
+ *       as don't care byte.
+ */
 static int do_acpi_entry(const char *filename,
                         void *symval, char *alias)
 {
         DEF_FIELD_ADDR(symval, acpi_device_id, id);
-        sprintf(alias, "acpi*:%s:*", *id);
+        DEF_FIELD_ADDR(symval, acpi_device_id, cls);
+        DEF_FIELD_ADDR(symval, acpi_device_id, cls_msk);
+
+        if (id && strlen((const char *)*id))
+                sprintf(alias, "acpi*:%s:*", *id);
+        else if (cls) {
+                int i, byte_shift, cnt = 0;
+                unsigned int msk;
+
+                sprintf(&alias[cnt], "acpi*:");
+                cnt = 6;
+                for (i = 1; i <= 3; i++) {
+                        byte_shift = 8 * (3-i);
+                        msk = (*cls_msk >> byte_shift) & 0xFF;
+                        if (msk)
+                                sprintf(&alias[cnt], "%02x",
+                                        (*cls >> byte_shift) & 0xFF);
+                        else
+                                sprintf(&alias[cnt], "??");
+                        cnt += 2;
+                }
+                sprintf(&alias[cnt], ":*");
+        }
         return 1;
 }
 ADD_TO_DEVTABLE("acpi", acpi_device_id, do_acpi_entry);