diff options
Diffstat (limited to 'drivers/staging/greybus/vibrator.c')
-rw-r--r-- | drivers/staging/greybus/vibrator.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/staging/greybus/vibrator.c b/drivers/staging/greybus/vibrator.c new file mode 100644 index 0000000..4ba0e16 --- /dev/null +++ b/drivers/staging/greybus/vibrator.c @@ -0,0 +1,249 @@ +/* + * Greybus Vibrator protocol driver. + * + * Copyright 2014 Google Inc. + * Copyright 2014 Linaro Ltd. + * + * Released under the GPLv2 only. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/kdev_t.h> +#include <linux/idr.h> +#include <linux/pm_runtime.h> + +#include "greybus.h" + +struct gb_vibrator_device { + struct gb_connection *connection; + struct device *dev; + int minor; /* vibrator minor number */ + struct delayed_work delayed_work; +}; + +/* Greybus Vibrator operation types */ +#define GB_VIBRATOR_TYPE_ON 0x02 +#define GB_VIBRATOR_TYPE_OFF 0x03 + +static int turn_off(struct gb_vibrator_device *vib) +{ + struct gb_bundle *bundle = vib->connection->bundle; + int ret; + + ret = gb_operation_sync(vib->connection, GB_VIBRATOR_TYPE_OFF, + NULL, 0, NULL, 0); + + gb_pm_runtime_put_autosuspend(bundle); + + return ret; +} + +static int turn_on(struct gb_vibrator_device *vib, u16 timeout_ms) +{ + struct gb_bundle *bundle = vib->connection->bundle; + int ret; + + ret = gb_pm_runtime_get_sync(bundle); + if (ret) + return ret; + + /* Vibrator was switched ON earlier */ + if (cancel_delayed_work_sync(&vib->delayed_work)) + turn_off(vib); + + ret = gb_operation_sync(vib->connection, GB_VIBRATOR_TYPE_ON, + NULL, 0, NULL, 0); + if (ret) { + gb_pm_runtime_put_autosuspend(bundle); + return ret; + } + + schedule_delayed_work(&vib->delayed_work, msecs_to_jiffies(timeout_ms)); + + return 0; +} + +static void gb_vibrator_worker(struct work_struct *work) +{ + struct delayed_work *delayed_work = to_delayed_work(work); + struct gb_vibrator_device *vib = + container_of(delayed_work, struct gb_vibrator_device, delayed_work); + + turn_off(vib); +} + +static ssize_t timeout_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct gb_vibrator_device *vib = dev_get_drvdata(dev); + unsigned long val; + int retval; + + retval = kstrtoul(buf, 10, &val); + if (retval < 0) { + dev_err(dev, "could not parse timeout value %d\n", retval); + return retval; + } + + if (val) + retval = turn_on(vib, (u16)val); + else + retval = turn_off(vib); + if (retval) + return retval; + + return count; +} +static DEVICE_ATTR_WO(timeout); + +static struct attribute *vibrator_attrs[] = { + &dev_attr_timeout.attr, + NULL, +}; +ATTRIBUTE_GROUPS(vibrator); + +static struct class vibrator_class = { + .name = "vibrator", + .owner = THIS_MODULE, + .dev_groups = vibrator_groups, +}; + +static DEFINE_IDA(minors); + +static int gb_vibrator_probe(struct gb_bundle *bundle, + const struct greybus_bundle_id *id) +{ + struct greybus_descriptor_cport *cport_desc; + struct gb_connection *connection; + struct gb_vibrator_device *vib; + struct device *dev; + int retval; + + if (bundle->num_cports != 1) + return -ENODEV; + + cport_desc = &bundle->cport_desc[0]; + if (cport_desc->protocol_id != GREYBUS_PROTOCOL_VIBRATOR) + return -ENODEV; + + vib = kzalloc(sizeof(*vib), GFP_KERNEL); + if (!vib) + return -ENOMEM; + + connection = gb_connection_create(bundle, le16_to_cpu(cport_desc->id), + NULL); + if (IS_ERR(connection)) { + retval = PTR_ERR(connection); + goto err_free_vib; + } + gb_connection_set_data(connection, vib); + + vib->connection = connection; + + greybus_set_drvdata(bundle, vib); + + retval = gb_connection_enable(connection); + if (retval) + goto err_connection_destroy; + + /* + * For now we create a device in sysfs for the vibrator, but odds are + * there is a "real" device somewhere in the kernel for this, but I + * can't find it at the moment... + */ + vib->minor = ida_simple_get(&minors, 0, 0, GFP_KERNEL); + if (vib->minor < 0) { + retval = vib->minor; + goto err_connection_disable; + } + dev = device_create(&vibrator_class, &bundle->dev, + MKDEV(0, 0), vib, "vibrator%d", vib->minor); + if (IS_ERR(dev)) { + retval = -EINVAL; + goto err_ida_remove; + } + vib->dev = dev; + + INIT_DELAYED_WORK(&vib->delayed_work, gb_vibrator_worker); + + gb_pm_runtime_put_autosuspend(bundle); + + return 0; + +err_ida_remove: + ida_simple_remove(&minors, vib->minor); +err_connection_disable: + gb_connection_disable(connection); +err_connection_destroy: + gb_connection_destroy(connection); +err_free_vib: + kfree(vib); + + return retval; +} + +static void gb_vibrator_disconnect(struct gb_bundle *bundle) +{ + struct gb_vibrator_device *vib = greybus_get_drvdata(bundle); + int ret; + + ret = gb_pm_runtime_get_sync(bundle); + if (ret) + gb_pm_runtime_get_noresume(bundle); + + if (cancel_delayed_work_sync(&vib->delayed_work)) + turn_off(vib); + + device_unregister(vib->dev); + ida_simple_remove(&minors, vib->minor); + gb_connection_disable(vib->connection); + gb_connection_destroy(vib->connection); + kfree(vib); +} + +static const struct greybus_bundle_id gb_vibrator_id_table[] = { + { GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_VIBRATOR) }, + { } +}; +MODULE_DEVICE_TABLE(greybus, gb_vibrator_id_table); + +static struct greybus_driver gb_vibrator_driver = { + .name = "vibrator", + .probe = gb_vibrator_probe, + .disconnect = gb_vibrator_disconnect, + .id_table = gb_vibrator_id_table, +}; + +static __init int gb_vibrator_init(void) +{ + int retval; + + retval = class_register(&vibrator_class); + if (retval) + return retval; + + retval = greybus_register(&gb_vibrator_driver); + if (retval) + goto err_class_unregister; + + return 0; + +err_class_unregister: + class_unregister(&vibrator_class); + + return retval; +} +module_init(gb_vibrator_init); + +static __exit void gb_vibrator_exit(void) +{ + greybus_deregister(&gb_vibrator_driver); + class_unregister(&vibrator_class); + ida_destroy(&minors); +} +module_exit(gb_vibrator_exit); + +MODULE_LICENSE("GPL v2"); |