*
* Create a platform device object which can have other objects attached
* to it, and which will have attached objects freed when it is released.
+ *
+ * This device will be marked as not supporting hotpluggable drivers; no
+ * device add/remove uevents will be generated. In the unusual case that
+ * the device isn't being dynamically allocated as a legacy "probe the
+ * hardware" driver, infrastructure code should reverse this marking.
*/
struct platform_device *platform_device_alloc(const char *name, unsigned int id)
{
pa->pdev.id = id;
device_initialize(&pa->pdev.dev);
pa->pdev.dev.release = platform_device_release;
+
+ /* prevent hotplug "modprobe $(MODALIAS)" from causing trouble in
+ * legacy probe-the-hardware drivers, which don't properly split
+ * out device enumeration logic from drivers.
+ */
+ pa->pdev.dev.uevent_suppress = 1;
}
return pa ? &pa->pdev : NULL;
* pointer. The memory associated with the platform data will be freed
* when the platform device is released.
*/
-int platform_device_add_data(struct platform_device *pdev, void *data, size_t size)
+int platform_device_add_data(struct platform_device *pdev, const void *data, size_t size)
{
void *d;
pr_debug("Registering platform device '%s'. Parent at %s\n",
pdev->dev.bus_id, pdev->dev.parent->bus_id);
- ret = device_register(&pdev->dev);
+ ret = device_add(&pdev->dev);
if (ret == 0)
return ret;
* @pdev: platform device we're removing
*
* Note that this function will also release all memory- and port-based
- * resources owned by the device (@dev->resource).
+ * resources owned by the device (@dev->resource). This function
+ * must _only_ be externally called in error cases. All other usage
+ * is a bug.
*/
void platform_device_del(struct platform_device *pdev)
{
int i;
if (pdev) {
+ device_del(&pdev->dev);
+
for (i = 0; i < pdev->num_resources; i++) {
struct resource *r = &pdev->resource[i];
if (r->flags & (IORESOURCE_MEM|IORESOURCE_IO))
release_resource(r);
}
-
- device_del(&pdev->dev);
}
}
EXPORT_SYMBOL_GPL(platform_device_del);
* memory allocated for the device allows drivers using such devices
* to be unloaded iwithout waiting for the last reference to the device
* to be dropped.
+ *
+ * This interface is primarily intended for use with legacy drivers
+ * which probe hardware directly. Because such drivers create sysfs
+ * device nodes themselves, rather than letting system infrastructure
+ * handle such device enumeration tasks, they don't fully conform to
+ * the Linux driver model. In particular, when such drivers are built
+ * as modules, they can't be "hotplugged".
*/
struct platform_device *platform_device_register_simple(char *name, unsigned int id,
struct resource *res, unsigned int num)
return drv->probe(dev);
}
+static int platform_drv_probe_fail(struct device *_dev)
+{
+ return -ENXIO;
+}
+
static int platform_drv_remove(struct device *_dev)
{
struct platform_driver *drv = to_platform_driver(_dev->driver);
}
EXPORT_SYMBOL_GPL(platform_driver_unregister);
+/**
+ * platform_driver_probe - register driver for non-hotpluggable device
+ * @drv: platform driver structure
+ * @probe: the driver probe routine, probably from an __init section
+ *
+ * Use this instead of platform_driver_register() when you know the device
+ * is not hotpluggable and has already been registered, and you want to
+ * remove its run-once probe() infrastructure from memory after the driver
+ * has bound to the device.
+ *
+ * One typical use for this would be with drivers for controllers integrated
+ * into system-on-chip processors, where the controller devices have been
+ * configured as part of board setup.
+ *
+ * Returns zero if the driver registered and bound to a device, else returns
+ * a negative error code and with the driver not registered.
+ */
+int __init_or_module platform_driver_probe(struct platform_driver *drv,
+ int (*probe)(struct platform_device *))
+{
+ int retval, code;
+
+ /* temporary section violation during probe() */
+ drv->probe = probe;
+ retval = code = platform_driver_register(drv);
+
+ /* Fixup that section violation, being paranoid about code scanning
+ * the list of drivers in order to probe new devices. Check to see
+ * if the probe was successful, and make sure any forced probes of
+ * new devices fail.
+ */
+ spin_lock(&platform_bus_type.klist_drivers.k_lock);
+ drv->probe = NULL;
+ if (code == 0 && list_empty(&drv->driver.klist_devices.k_list))
+ retval = -ENODEV;
+ drv->driver.probe = platform_drv_probe_fail;
+ spin_unlock(&platform_bus_type.klist_drivers.k_lock);
+
+ if (code != retval)
+ platform_driver_unregister(drv);
+ return retval;
+}
+EXPORT_SYMBOL_GPL(platform_driver_probe);
+
+/* modalias support enables more hands-off userspace setup:
+ * (a) environment variable lets new-style hotplug events work once system is
+ * fully running: "modprobe $MODALIAS"
+ * (b) sysfs attribute lets new-style coldplug recover from hotplug events
+ * mishandled before system is fully running: "modprobe $(cat modalias)"
+ */
+static ssize_t
+modalias_show(struct device *dev, struct device_attribute *a, char *buf)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ int len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->name);
+
+ return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+
+static struct device_attribute platform_dev_attrs[] = {
+ __ATTR_RO(modalias),
+ __ATTR_NULL,
+};
+
+static int platform_uevent(struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+
+ envp[0] = buffer;
+ snprintf(buffer, buffer_size, "MODALIAS=%s", pdev->name);
+ return 0;
+}
+
/**
* platform_match - bind platform device to platform driver.
return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0);
}
-static int platform_suspend(struct device * dev, pm_message_t state)
+static int platform_suspend(struct device *dev, pm_message_t mesg)
{
int ret = 0;
if (dev->driver && dev->driver->suspend)
- ret = dev->driver->suspend(dev, state);
+ ret = dev->driver->suspend(dev, mesg);
+
+ return ret;
+}
+
+static int platform_suspend_late(struct device *dev, pm_message_t mesg)
+{
+ struct platform_driver *drv = to_platform_driver(dev->driver);
+ struct platform_device *pdev = container_of(dev, struct platform_device, dev);
+ int ret = 0;
+
+ if (dev->driver && drv->suspend_late)
+ ret = drv->suspend_late(pdev, mesg);
+
+ return ret;
+}
+
+static int platform_resume_early(struct device *dev)
+{
+ struct platform_driver *drv = to_platform_driver(dev->driver);
+ struct platform_device *pdev = container_of(dev, struct platform_device, dev);
+ int ret = 0;
+
+ if (dev->driver && drv->resume_early)
+ ret = drv->resume_early(pdev);
return ret;
}
struct bus_type platform_bus_type = {
.name = "platform",
+ .dev_attrs = platform_dev_attrs,
.match = platform_match,
+ .uevent = platform_uevent,
.suspend = platform_suspend,
+ .suspend_late = platform_suspend_late,
+ .resume_early = platform_resume_early,
.resume = platform_resume,
};
EXPORT_SYMBOL_GPL(platform_bus_type);
int __init platform_bus_init(void)
{
- device_register(&platform_bus);
- return bus_register(&platform_bus_type);
+ int error;
+
+ error = device_register(&platform_bus);
+ if (error)
+ return error;
+ error = bus_register(&platform_bus_type);
+ if (error)
+ device_unregister(&platform_bus);
+ return error;
}
#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
projects / linux-2.6-omap-h63xx.git / blobdiff