summaryrefslogtreecommitdiff
path: root/include/linux/acpi.h
diff options
context:
space:
mode:
authorZhang Rui <rui.zhang@intel.com>2014-01-14 12:46:36 +0400
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-01-17 02:10:40 +0400
commit6eb2451f7c43c4a7f84ae7b613ea975317b951f1 (patch)
tree7ff8db97b03fa018bd4d7628186e35523a82ac04 /include/linux/acpi.h
parent3d8e00909df96c2d3eace3996748be9c0a437e5a (diff)
downloadlinux-6eb2451f7c43c4a7f84ae7b613ea975317b951f1.tar.xz
ACPI: add module autoloading support for ACPI enumerated devices
An ACPI enumerated device may have its compatible id strings. To support the compatible ACPI ids (acpi_device->pnp.ids), we introduced acpi_driver_match_device() to match the driver->acpi_match_table and acpi_device->pnp.ids. For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to exports the driver module alias in the format of "acpi:device_compatible_ids". But in the mean time, the current code does not export the ACPI compatible strings as part of the module_alias for the ACPI enumerated devices, which will break the module autoloading. Take the following piece of code for example, static const struct acpi_device_id xxx_acpi_match[] = { { "INTABCD", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, xxx_acpi_match); If this piece of code is used in a platform driver for an ACPI enumerated platform device, the platform driver module_alias is "acpi:INTABCD", but the uevent attribute of its platform device node is "platform:INTABCD:00" (PREFIX:platform_device->name). If this piece of code is used in an i2c driver for an ACPI enumerated i2c device, the i2c driver module_alias is "acpi:INTABCD", but the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name). If this piece of code is used in an spi driver for an ACPI enumerated spi device, the spi driver module_alias is "acpi:INTABCD", but the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias). The reason why the module autoloading is not broken for now is that the uevent file of the ACPI device node is "acpi:INTABCD". Thus it is the ACPI device node creation that loads the platform/i2c/spi driver. So this is a problem that will affect us the day when the ACPI bus is removed from device model. This patch introduces two new APIs, one for exporting ACPI ids in uevent MODALIAS field, and another for exporting ACPI ids in device' modalias sysfs attribute. For any bus that supports ACPI enumerated devices, it needs to invoke these two functions for their uevent and modalias attribute. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'include/linux/acpi.h')
-rw-r--r--include/linux/acpi.h15
1 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index d9099b15b472..22325ed24139 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -409,6 +409,9 @@ static inline bool acpi_driver_match_device(struct device *dev,
return !!acpi_match_device(drv->acpi_match_table, dev);
}
+int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *);
+int acpi_device_modalias(struct device *, char *, int);
+
#define ACPI_PTR(_ptr) (_ptr)
#else /* !CONFIG_ACPI */
@@ -488,6 +491,18 @@ static inline bool acpi_driver_match_device(struct device *dev,
return false;
}
+static inline int acpi_device_uevent_modalias(struct device *dev,
+ struct kobj_uevent_env *env)
+{
+ return -ENODEV;
+}
+
+static inline int acpi_device_modalias(struct device *dev,
+ char *buf, int size)
+{
+ return -ENODEV;
+}
+
#define ACPI_PTR(_ptr) (NULL)
#endif /* !CONFIG_ACPI */