From: Russell King Date: Sat, 5 Nov 2005 21:19:33 +0000 (+0000) Subject: [DRIVER MODEL] Improved dynamically allocated platform_device interface X-Git-Tag: v2.6.15-rc1~715^2~6 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=37c12e7497b6fe2b6a890814f0ff4edce696d862;p=linux-2.6 [DRIVER MODEL] Improved dynamically allocated platform_device interface Re-jig the simple platform device support to allow private data to be attached to a platform device, as well as allowing the parent device to be set. Example usage: pdev = platform_device_alloc("mydev", id); if (pdev) { err = platform_device_add_resources(pdev, &resources, ARRAY_SIZE(resources)); if (err == 0) err = platform_device_add_data(pdev, &platform_data, sizeof(platform_data)); if (err == 0) err = platform_device_add(pdev); } else { err = -ENOMEM; } if (err) platform_device_put(pdev); Signed-off-by: Russell King Acked-by: Greg Kroah-Hartman --- diff --git a/drivers/base/platform.c b/drivers/base/platform.c index d597c922af..6d4736e89f 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -116,12 +116,115 @@ int platform_add_devices(struct platform_device **devs, int num) return ret; } +struct platform_object { + struct platform_device pdev; + char name[1]; +}; + /** - * platform_device_register - add a platform-level device + * platform_device_put + * @pdev: platform device to free + * + * Free all memory associated with a platform device. This function + * must _only_ be externally called in error cases. All other usage + * is a bug. + */ +void platform_device_put(struct platform_device *pdev) +{ + if (pdev) + put_device(&pdev->dev); +} +EXPORT_SYMBOL_GPL(platform_device_put); + +static void platform_device_release(struct device *dev) +{ + struct platform_object *pa = container_of(dev, struct platform_object, pdev.dev); + + kfree(pa->pdev.dev.platform_data); + kfree(pa->pdev.resource); + kfree(pa); +} + +/** + * platform_device_alloc + * @name: base name of the device we're adding + * @id: instance id + * + * Create a platform device object which can have other objects attached + * to it, and which will have attached objects freed when it is released. + */ +struct platform_device *platform_device_alloc(const char *name, unsigned int id) +{ + struct platform_object *pa; + + pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL); + if (pa) { + strcpy(pa->name, name); + pa->pdev.name = pa->name; + pa->pdev.id = id; + device_initialize(&pa->pdev.dev); + pa->pdev.dev.release = platform_device_release; + } + + return pa ? &pa->pdev : NULL; +} +EXPORT_SYMBOL_GPL(platform_device_alloc); + +/** + * platform_device_add_resources + * @pdev: platform device allocated by platform_device_alloc to add resources to + * @res: set of resources that needs to be allocated for the device + * @num: number of resources + * + * Add a copy of the resources to the platform device. The memory + * associated with the resources will be freed when the platform + * device is released. + */ +int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num) +{ + struct resource *r; + + r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL); + if (r) { + memcpy(r, res, sizeof(struct resource) * num); + pdev->resource = r; + pdev->num_resources = num; + } + return r ? 0 : -ENOMEM; +} +EXPORT_SYMBOL_GPL(platform_device_add_resources); + +/** + * platform_device_add_data + * @pdev: platform device allocated by platform_device_alloc to add resources to + * @data: platform specific data for this platform device + * @size: size of platform specific data + * + * Add a copy of platform specific data to the platform device's platform_data + * 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) +{ + void *d; + + d = kmalloc(size, GFP_KERNEL); + if (d) { + memcpy(d, data, size); + pdev->dev.platform_data = d; + } + return d ? 0 : -ENOMEM; +} +EXPORT_SYMBOL_GPL(platform_device_add_data); + +/** + * platform_device_add - add a platform device to device hierarchy * @pdev: platform device we're adding * + * This is part 2 of platform_device_register(), though may be called + * separately _iff_ pdev was allocated by platform_device_alloc(). */ -int platform_device_register(struct platform_device * pdev) +int platform_device_add(struct platform_device *pdev) { int i, ret = 0; @@ -174,6 +277,18 @@ int platform_device_register(struct platform_device * pdev) release_resource(&pdev->resource[i]); return ret; } +EXPORT_SYMBOL_GPL(platform_device_add); + +/** + * platform_device_register - add a platform-level device + * @pdev: platform device we're adding + * + */ +int platform_device_register(struct platform_device * pdev) +{ + device_initialize(&pdev->dev); + return platform_device_add(pdev); +} /** * platform_device_unregister - remove a platform-level device @@ -197,18 +312,6 @@ void platform_device_unregister(struct platform_device * pdev) } } -struct platform_object { - struct platform_device pdev; - struct resource resources[0]; -}; - -static void platform_device_release_simple(struct device *dev) -{ - struct platform_device *pdev = to_platform_device(dev); - - kfree(container_of(pdev, struct platform_object, pdev)); -} - /** * platform_device_register_simple * @name: base name of the device we're adding @@ -225,33 +328,29 @@ static void platform_device_release_simple(struct device *dev) struct platform_device *platform_device_register_simple(char *name, unsigned int id, struct resource *res, unsigned int num) { - struct platform_object *pobj; + struct platform_device *pdev; int retval; - pobj = kzalloc(sizeof(*pobj) + sizeof(struct resource) * num, GFP_KERNEL); - if (!pobj) { + pdev = platform_device_alloc(name, id); + if (!pdev) { retval = -ENOMEM; goto error; } - pobj->pdev.name = name; - pobj->pdev.id = id; - pobj->pdev.dev.release = platform_device_release_simple; - if (num) { - memcpy(pobj->resources, res, sizeof(struct resource) * num); - pobj->pdev.resource = pobj->resources; - pobj->pdev.num_resources = num; + retval = platform_device_add_resources(pdev, res, num); + if (retval) + goto error; } - retval = platform_device_register(&pobj->pdev); + retval = platform_device_add(pdev); if (retval) goto error; - return &pobj->pdev; + return pdev; error: - kfree(pobj); + platform_device_put(pdev); return ERR_PTR(retval); } diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index a726225e0a..1a165b7ae0 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -37,4 +37,10 @@ extern int platform_add_devices(struct platform_device **, int); extern struct platform_device *platform_device_register_simple(char *, unsigned int, struct resource *, unsigned int); +extern struct platform_device *platform_device_alloc(const char *name, unsigned int id); +extern int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num); +extern int platform_device_add_data(struct platform_device *pdev, void *data, size_t size); +extern int platform_device_add(struct platform_device *pdev); +extern void platform_device_put(struct platform_device *pdev); + #endif /* _PLATFORM_DEVICE_H_ */