Add helper functions to create a device on the auxiliary bus. This is meant for fairly simple usage of the auxiliary bus, to avoid having the same code repeated in the different drivers.
Suggested-by: Stephen Boyd <sb...@kernel.org> Cc: Arnd Bergmann <a...@arndb.de> Signed-off-by: Jerome Brunet <jbru...@baylibre.com> --- drivers/base/auxiliary.c | 108 ++++++++++++++++++++++++++++++++++++++++++ include/linux/auxiliary_bus.h | 17 +++++++ 2 files changed, 125 insertions(+) diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c index afa4df4c5a3f371b91d8dd8c4325495d32ad1291..a6d46c2759be81a0739f07528d5959c2a76eb8a8 100644 --- a/drivers/base/auxiliary.c +++ b/drivers/base/auxiliary.c @@ -385,6 +385,114 @@ void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv) } EXPORT_SYMBOL_GPL(auxiliary_driver_unregister); +static void auxiliary_device_release(struct device *dev) +{ + struct auxiliary_device *auxdev = to_auxiliary_dev(dev); + + kfree(auxdev); +} + +/** + * auxiliary_device_create - create a device on the auxiliary bus + * @dev: parent device + * @modname: module name used to create the auxiliary driver name. + * @devname: auxiliary bus device name + * @platform_data: auxiliary bus device platform data + * @id: auxiliary bus device id + * + * Helper to create an auxiliary bus device. + * The device created matches driver 'modname.devname' on the auxiliary bus. + */ +struct auxiliary_device *auxiliary_device_create(struct device *dev, + const char *modname, + const char *devname, + void *platform_data, + int id) +{ + struct auxiliary_device *auxdev; + int ret; + + auxdev = kzalloc(sizeof(*auxdev), GFP_KERNEL); + if (!auxdev) + return NULL; + + auxdev->id = id; + auxdev->name = devname; + auxdev->dev.parent = dev; + auxdev->dev.platform_data = platform_data; + auxdev->dev.release = auxiliary_device_release; + device_set_of_node_from_dev(&auxdev->dev, dev); + + ret = auxiliary_device_init(auxdev); + if (ret) { + kfree(auxdev); + return NULL; + } + + ret = __auxiliary_device_add(auxdev, modname); + if (ret) { + /* + * It may look odd but auxdev should not be freed here. + * auxiliary_device_uninit() calls device_put() which call + * the device release function, freeing auxdev. + */ + auxiliary_device_uninit(auxdev); + return NULL; + } + + return auxdev; +} +EXPORT_SYMBOL_GPL(auxiliary_device_create); + +/** + * auxiliary_device_destroy - remove an auxiliary device + * @auxdev: pointer to the auxdev to be removed + * + * Helper to remove an auxiliary device created with + * auxiliary_device_create() + */ +void auxiliary_device_destroy(void *auxdev) +{ + struct auxiliary_device *_auxdev = auxdev; + + auxiliary_device_delete(_auxdev); + auxiliary_device_uninit(_auxdev); +} +EXPORT_SYMBOL_GPL(auxiliary_device_destroy); + +/** + * __devm_auxiliary_device_create - create a managed device on the auxiliary bus + * @dev: parent device + * @modname: module name used to create the auxiliary driver name. + * @devname: auxiliary bus device name + * @platform_data: auxiliary bus device platform data + * @id: auxiliary bus device id + * + * Device managed helper to create an auxiliary bus device. + * The device created matches driver 'modname.devname' on the auxiliary bus. + */ +struct auxiliary_device *__devm_auxiliary_device_create(struct device *dev, + const char *modname, + const char *devname, + void *platform_data, + int id) +{ + struct auxiliary_device *auxdev; + int ret; + + auxdev = auxiliary_device_create(dev, modname, devname, platform_data, id); + if (IS_ERR(auxdev)) + return auxdev; + + ret = devm_add_action_or_reset(dev, auxiliary_device_destroy, + auxdev); + if (ret) + return ERR_PTR(ret); + + return auxdev; +} +EXPORT_SYMBOL_GPL(__devm_auxiliary_device_create); + void __init auxiliary_bus_init(void) { WARN_ON(bus_register(&auxiliary_bus_type)); diff --git a/include/linux/auxiliary_bus.h b/include/linux/auxiliary_bus.h index 65dd7f15437474468acf0e28f6932a7ff2cfff2c..4086afd0cc6b96084c190f24acc304cde5d1749a 100644 --- a/include/linux/auxiliary_bus.h +++ b/include/linux/auxiliary_bus.h @@ -254,6 +254,23 @@ int __auxiliary_driver_register(struct auxiliary_driver *auxdrv, struct module * void auxiliary_driver_unregister(struct auxiliary_driver *auxdrv); +struct auxiliary_device *auxiliary_device_create(struct device *dev, + const char *modname, + const char *devname, + void *platform_data, + int id); +void auxiliary_device_destroy(void *auxdev); + +struct auxiliary_device *__devm_auxiliary_device_create(struct device *dev, + const char *modname, + const char *devname, + void *platform_data, + int id); + +#define devm_auxiliary_device_create(dev, devname, platform_data) \ + __devm_auxiliary_device_create(dev, KBUILD_MODNAME, devname, \ + platform_data, 0) + /** * module_auxiliary_driver() - Helper macro for registering an auxiliary driver * @__auxiliary_driver: auxiliary driver struct -- 2.47.2