| 1 | /* |
| 2 | * Greybus Vibrator protocol driver. |
| 3 | * |
| 4 | * Copyright 2014 Google Inc. |
| 5 | * Copyright 2014 Linaro Ltd. |
| 6 | * |
| 7 | * Released under the GPLv2 only. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/device.h> |
| 14 | #include <linux/kdev_t.h> |
| 15 | #include <linux/idr.h> |
| 16 | #include <linux/pm_runtime.h> |
| 17 | |
| 18 | #include "greybus.h" |
| 19 | |
| 20 | struct gb_vibrator_device { |
| 21 | struct gb_connection *connection; |
| 22 | struct device *dev; |
| 23 | int minor; /* vibrator minor number */ |
| 24 | struct delayed_work delayed_work; |
| 25 | }; |
| 26 | |
| 27 | /* Greybus Vibrator operation types */ |
| 28 | #define GB_VIBRATOR_TYPE_ON 0x02 |
| 29 | #define GB_VIBRATOR_TYPE_OFF 0x03 |
| 30 | |
| 31 | static int turn_off(struct gb_vibrator_device *vib) |
| 32 | { |
| 33 | struct gb_bundle *bundle = vib->connection->bundle; |
| 34 | int ret; |
| 35 | |
| 36 | ret = gb_operation_sync(vib->connection, GB_VIBRATOR_TYPE_OFF, |
| 37 | NULL, 0, NULL, 0); |
| 38 | |
| 39 | gb_pm_runtime_put_autosuspend(bundle); |
| 40 | |
| 41 | return ret; |
| 42 | } |
| 43 | |
| 44 | static int turn_on(struct gb_vibrator_device *vib, u16 timeout_ms) |
| 45 | { |
| 46 | struct gb_bundle *bundle = vib->connection->bundle; |
| 47 | int ret; |
| 48 | |
| 49 | ret = gb_pm_runtime_get_sync(bundle); |
| 50 | if (ret) |
| 51 | return ret; |
| 52 | |
| 53 | /* Vibrator was switched ON earlier */ |
| 54 | if (cancel_delayed_work_sync(&vib->delayed_work)) |
| 55 | turn_off(vib); |
| 56 | |
| 57 | ret = gb_operation_sync(vib->connection, GB_VIBRATOR_TYPE_ON, |
| 58 | NULL, 0, NULL, 0); |
| 59 | if (ret) { |
| 60 | gb_pm_runtime_put_autosuspend(bundle); |
| 61 | return ret; |
| 62 | } |
| 63 | |
| 64 | schedule_delayed_work(&vib->delayed_work, msecs_to_jiffies(timeout_ms)); |
| 65 | |
| 66 | return 0; |
| 67 | } |
| 68 | |
| 69 | static void gb_vibrator_worker(struct work_struct *work) |
| 70 | { |
| 71 | struct delayed_work *delayed_work = to_delayed_work(work); |
| 72 | struct gb_vibrator_device *vib = |
| 73 | container_of(delayed_work, struct gb_vibrator_device, delayed_work); |
| 74 | |
| 75 | turn_off(vib); |
| 76 | } |
| 77 | |
| 78 | static ssize_t timeout_store(struct device *dev, struct device_attribute *attr, |
| 79 | const char *buf, size_t count) |
| 80 | { |
| 81 | struct gb_vibrator_device *vib = dev_get_drvdata(dev); |
| 82 | unsigned long val; |
| 83 | int retval; |
| 84 | |
| 85 | retval = kstrtoul(buf, 10, &val); |
| 86 | if (retval < 0) { |
| 87 | dev_err(dev, "could not parse timeout value %d\n", retval); |
| 88 | return retval; |
| 89 | } |
| 90 | |
| 91 | if (val) |
| 92 | retval = turn_on(vib, (u16)val); |
| 93 | else |
| 94 | retval = turn_off(vib); |
| 95 | if (retval) |
| 96 | return retval; |
| 97 | |
| 98 | return count; |
| 99 | } |
| 100 | static DEVICE_ATTR_WO(timeout); |
| 101 | |
| 102 | static struct attribute *vibrator_attrs[] = { |
| 103 | &dev_attr_timeout.attr, |
| 104 | NULL, |
| 105 | }; |
| 106 | ATTRIBUTE_GROUPS(vibrator); |
| 107 | |
| 108 | static struct class vibrator_class = { |
| 109 | .name = "vibrator", |
| 110 | .owner = THIS_MODULE, |
| 111 | .dev_groups = vibrator_groups, |
| 112 | }; |
| 113 | |
| 114 | static DEFINE_IDA(minors); |
| 115 | |
| 116 | static int gb_vibrator_probe(struct gb_bundle *bundle, |
| 117 | const struct greybus_bundle_id *id) |
| 118 | { |
| 119 | struct greybus_descriptor_cport *cport_desc; |
| 120 | struct gb_connection *connection; |
| 121 | struct gb_vibrator_device *vib; |
| 122 | struct device *dev; |
| 123 | int retval; |
| 124 | |
| 125 | if (bundle->num_cports != 1) |
| 126 | return -ENODEV; |
| 127 | |
| 128 | cport_desc = &bundle->cport_desc[0]; |
| 129 | if (cport_desc->protocol_id != GREYBUS_PROTOCOL_VIBRATOR) |
| 130 | return -ENODEV; |
| 131 | |
| 132 | vib = kzalloc(sizeof(*vib), GFP_KERNEL); |
| 133 | if (!vib) |
| 134 | return -ENOMEM; |
| 135 | |
| 136 | connection = gb_connection_create(bundle, le16_to_cpu(cport_desc->id), |
| 137 | NULL); |
| 138 | if (IS_ERR(connection)) { |
| 139 | retval = PTR_ERR(connection); |
| 140 | goto err_free_vib; |
| 141 | } |
| 142 | gb_connection_set_data(connection, vib); |
| 143 | |
| 144 | vib->connection = connection; |
| 145 | |
| 146 | greybus_set_drvdata(bundle, vib); |
| 147 | |
| 148 | retval = gb_connection_enable(connection); |
| 149 | if (retval) |
| 150 | goto err_connection_destroy; |
| 151 | |
| 152 | /* |
| 153 | * For now we create a device in sysfs for the vibrator, but odds are |
| 154 | * there is a "real" device somewhere in the kernel for this, but I |
| 155 | * can't find it at the moment... |
| 156 | */ |
| 157 | vib->minor = ida_simple_get(&minors, 0, 0, GFP_KERNEL); |
| 158 | if (vib->minor < 0) { |
| 159 | retval = vib->minor; |
| 160 | goto err_connection_disable; |
| 161 | } |
| 162 | dev = device_create(&vibrator_class, &bundle->dev, |
| 163 | MKDEV(0, 0), vib, "vibrator%d", vib->minor); |
| 164 | if (IS_ERR(dev)) { |
| 165 | retval = -EINVAL; |
| 166 | goto err_ida_remove; |
| 167 | } |
| 168 | vib->dev = dev; |
| 169 | |
| 170 | INIT_DELAYED_WORK(&vib->delayed_work, gb_vibrator_worker); |
| 171 | |
| 172 | gb_pm_runtime_put_autosuspend(bundle); |
| 173 | |
| 174 | return 0; |
| 175 | |
| 176 | err_ida_remove: |
| 177 | ida_simple_remove(&minors, vib->minor); |
| 178 | err_connection_disable: |
| 179 | gb_connection_disable(connection); |
| 180 | err_connection_destroy: |
| 181 | gb_connection_destroy(connection); |
| 182 | err_free_vib: |
| 183 | kfree(vib); |
| 184 | |
| 185 | return retval; |
| 186 | } |
| 187 | |
| 188 | static void gb_vibrator_disconnect(struct gb_bundle *bundle) |
| 189 | { |
| 190 | struct gb_vibrator_device *vib = greybus_get_drvdata(bundle); |
| 191 | int ret; |
| 192 | |
| 193 | ret = gb_pm_runtime_get_sync(bundle); |
| 194 | if (ret) |
| 195 | gb_pm_runtime_get_noresume(bundle); |
| 196 | |
| 197 | if (cancel_delayed_work_sync(&vib->delayed_work)) |
| 198 | turn_off(vib); |
| 199 | |
| 200 | device_unregister(vib->dev); |
| 201 | ida_simple_remove(&minors, vib->minor); |
| 202 | gb_connection_disable(vib->connection); |
| 203 | gb_connection_destroy(vib->connection); |
| 204 | kfree(vib); |
| 205 | } |
| 206 | |
| 207 | static const struct greybus_bundle_id gb_vibrator_id_table[] = { |
| 208 | { GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_VIBRATOR) }, |
| 209 | { } |
| 210 | }; |
| 211 | MODULE_DEVICE_TABLE(greybus, gb_vibrator_id_table); |
| 212 | |
| 213 | static struct greybus_driver gb_vibrator_driver = { |
| 214 | .name = "vibrator", |
| 215 | .probe = gb_vibrator_probe, |
| 216 | .disconnect = gb_vibrator_disconnect, |
| 217 | .id_table = gb_vibrator_id_table, |
| 218 | }; |
| 219 | |
| 220 | static __init int gb_vibrator_init(void) |
| 221 | { |
| 222 | int retval; |
| 223 | |
| 224 | retval = class_register(&vibrator_class); |
| 225 | if (retval) |
| 226 | return retval; |
| 227 | |
| 228 | retval = greybus_register(&gb_vibrator_driver); |
| 229 | if (retval) |
| 230 | goto err_class_unregister; |
| 231 | |
| 232 | return 0; |
| 233 | |
| 234 | err_class_unregister: |
| 235 | class_unregister(&vibrator_class); |
| 236 | |
| 237 | return retval; |
| 238 | } |
| 239 | module_init(gb_vibrator_init); |
| 240 | |
| 241 | static __exit void gb_vibrator_exit(void) |
| 242 | { |
| 243 | greybus_deregister(&gb_vibrator_driver); |
| 244 | class_unregister(&vibrator_class); |
| 245 | ida_destroy(&minors); |
| 246 | } |
| 247 | module_exit(gb_vibrator_exit); |
| 248 | |
| 249 | MODULE_LICENSE("GPL v2"); |