Power management and ACPI material for v4.2-rc2

- Fix for an ACPI resources management regression introduced
    during the 4.1 cycle (that unfortunately went into -stable)
    effectively reverting the bad commit along with the recent
    fixups on top of it and using an alternative approach to
    address the underlying issue (Rafael J Wysocki).
 
  - Fix for a memory leak and an incorrect return value in an
    error code path in the ACPI LPSS (Low-Power Subsystem) driver
    (Rafael J Wysocki).
 
  - Fix for a leftover dangling pointer in an error code path in
    the new wakeup IRQ support code (Rafael J Wysocki).
 
  - Fix to prevent infinite loops (due to errors in other places)
    from happening in the core generic PM domains support code
    (Geert Uytterhoeven).
 
  - Hibernation documentation update/clarification (Uwe Geuder).
 
  - Support for _CLS-based device enumeration in the ACPI core
    and in the ATA subsystem (Suravee Suthikulpanit).
 
 /
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Merge tag 'pm+acpi-4.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "These are fixes on top of the previous PM+ACPI pull requests
  (including one fix for a 4.1 regression) and two commits adding
  _CLS-based device enumeration support to the ACPI core and the ATA
  subsystem that waited for the latest ACPICA changes to be merged.

  Specifics:

   - Fix for an ACPI resources management regression introduced during
     the 4.1 cycle (that unfortunately went into -stable) effectively
     reverting the bad commit along with the recent fixups on top of it
     and using an alternative approach to address the underlying issue
     (Rafael J Wysocki).

   - Fix for a memory leak and an incorrect return value in an error
     code path in the ACPI LPSS (Low-Power Subsystem) driver (Rafael J
     Wysocki).

   - Fix for a leftover dangling pointer in an error code path in the
     new wakeup IRQ support code (Rafael J Wysocki).

   - Fix to prevent infinite loops (due to errors in other places) from
     happening in the core generic PM domains support code (Geert
     Uytterhoeven).

   - Hibernation documentation update/clarification (Uwe Geuder).

   - Support for _CLS-based device enumeration in the ACPI core and in
     the ATA subsystem (Suravee Suthikulpanit)"

* tag 'pm+acpi-4.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / wakeirq: Avoid setting power.wakeirq too hastily
  ata: ahci_platform: Add ACPI _CLS matching
  ACPI / scan: Add support for ACPI _CLS device matching
  PM / hibernate: clarify resume documentation
  PM / Domains: Avoid infinite loops in attach/detach code
  ACPI / LPSS: Fix up acpi_lpss_create_device()
  ACPI / PNP: Reserve ACPI resources at the fs_initcall_sync stage
This commit is contained in:
Linus Torvalds 2015-07-08 17:34:51 -07:00
commit 883a2dfd6f
15 changed files with 148 additions and 240 deletions

View File

@ -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

View File

@ -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)

View File

@ -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);

View File

@ -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);

View File

@ -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);

View File

@ -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.

View File

@ -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,
},
};

View File

@ -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();
}

View File

@ -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);

View File

@ -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;
}
/**

View File

@ -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)

View File

@ -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 *))

View File

@ -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

View File

@ -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);

View File

@ -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);