drivers/usb/core/phy.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * A wrapper for multiple PHYs which passes all phy_* function calls to
   4  * multiple (actual) PHY devices. This is comes handy when initializing
   5  * all PHYs on a HCD and to keep them all in the same state.
   6  *
   7  * Copyright (C) 2018 Martin Blumenstingl <[email protected]>
   8  */
   9
  10 #include <linux/device.h>
  11 #include <linux/list.h>
  12 #include <linux/phy/phy.h>
  13 #include <linux/of.h>
  14
  15 #include "phy.h"
  16
  17 struct usb_phy_roothub {
  18         struct phy              *phy;
  19         struct list_head        list;
  20 };
  21
  22 /* Allocate the roothub_entry by specific name of phy */
  23 static int usb_phy_roothub_add_phy_by_name(struct device *dev, const char *name,
  24                                            struct list_head *list)
  25 {
  26         struct usb_phy_roothub *roothub_entry;
  27         struct phy *phy;
  28
  29         phy = devm_of_phy_get(dev, dev->of_node, name);
  30         if (IS_ERR(phy))
  31                 return PTR_ERR(phy);
  32
  33         roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
  34         if (!roothub_entry)
  35                 return -ENOMEM;
  36
  37         INIT_LIST_HEAD(&roothub_entry->list);
  38
  39         roothub_entry->phy = phy;
  40
  41         list_add_tail(&roothub_entry->list, list);
  42
  43         return 0;
  44 }
  45
  46 static int usb_phy_roothub_add_phy(struct device *dev, int index,
  47                                    struct list_head *list)
  48 {
  49         struct usb_phy_roothub *roothub_entry;
  50         struct phy *phy;
  51
  52         phy = devm_of_phy_get_by_index(dev, dev->of_node, index);
  53         if (IS_ERR(phy)) {
  54                 if (PTR_ERR(phy) == -ENODEV)
  55                         return 0;
  56                 else
  57                         return PTR_ERR(phy);
  58         }
  59
  60         roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
  61         if (!roothub_entry)
  62                 return -ENOMEM;
  63
  64         INIT_LIST_HEAD(&roothub_entry->list);
  65
  66         roothub_entry->phy = phy;
  67
  68         list_add_tail(&roothub_entry->list, list);
  69
  70         return 0;
  71 }
  72
  73 struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
  74 {
  75         struct usb_phy_roothub *phy_roothub;
  76         int i, num_phys, err;
  77
  78         if (!IS_ENABLED(CONFIG_GENERIC_PHY))
  79                 return NULL;
  80
  81         num_phys = of_count_phandle_with_args(dev->of_node, "phys",
  82                                               "#phy-cells");
  83         if (num_phys <= 0)
  84                 return NULL;
  85
  86         phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
  87         if (!phy_roothub)
  88                 return ERR_PTR(-ENOMEM);
  89
  90         INIT_LIST_HEAD(&phy_roothub->list);
  91
  92         if (!usb_phy_roothub_add_phy_by_name(dev, "usb2-phy", &phy_roothub->list))
  93                 return phy_roothub;
  94
  95         for (i = 0; i < num_phys; i++) {
  96                 err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list);
  97                 if (err)
  98                         return ERR_PTR(err);
  99         }
 100
 101         return phy_roothub;
 102 }
 103 EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc);
 104
 105 /**
 106  * usb_phy_roothub_alloc_usb3_phy - alloc the roothub
 107  * @dev: the device of the host controller
 108  *
 109  * Allocate the usb phy roothub if the host use a generic usb3-phy.
 110  *
 111  * Return: On success, a pointer to the usb_phy_roothub. Otherwise,
 112  * %NULL if no use usb3 phy or %-ENOMEM if out of memory.
 113  */
 114 struct usb_phy_roothub *usb_phy_roothub_alloc_usb3_phy(struct device *dev)
 115 {
 116         struct usb_phy_roothub *phy_roothub;
 117         int num_phys;
 118
 119         if (!IS_ENABLED(CONFIG_GENERIC_PHY))
 120                 return NULL;
 121
 122         num_phys = of_count_phandle_with_args(dev->of_node, "phys",
 123                                               "#phy-cells");
 124         if (num_phys <= 0)
 125                 return NULL;
 126
 127         phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
 128         if (!phy_roothub)
 129                 return ERR_PTR(-ENOMEM);
 130
 131         INIT_LIST_HEAD(&phy_roothub->list);
 132
 133         if (!usb_phy_roothub_add_phy_by_name(dev, "usb3-phy", &phy_roothub->list))
 134                 return phy_roothub;
 135
 136         return NULL;
 137 }
 138 EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc_usb3_phy);
 139
 140 int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub)
 141 {
 142         struct usb_phy_roothub *roothub_entry;
 143         struct list_head *head;
 144         int err;
 145
 146         if (!phy_roothub)
 147                 return 0;
 148
 149         head = &phy_roothub->list;
 150
 151         list_for_each_entry(roothub_entry, head, list) {
 152                 err = phy_init(roothub_entry->phy);
 153                 if (err)
 154                         goto err_exit_phys;
 155         }
 156
 157         return 0;
 158
 159 err_exit_phys:
 160         list_for_each_entry_continue_reverse(roothub_entry, head, list)
 161                 phy_exit(roothub_entry->phy);
 162
 163         return err;
 164 }
 165 EXPORT_SYMBOL_GPL(usb_phy_roothub_init);
 166
 167 int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub)
 168 {
 169         struct usb_phy_roothub *roothub_entry;
 170         struct list_head *head;
 171         int err, ret = 0;
 172
 173         if (!phy_roothub)
 174                 return 0;
 175
 176         head = &phy_roothub->list;
 177
 178         list_for_each_entry(roothub_entry, head, list) {
 179                 err = phy_exit(roothub_entry->phy);
 180                 if (err)
 181                         ret = err;
 182         }
 183
 184         return ret;
 185 }
 186 EXPORT_SYMBOL_GPL(usb_phy_roothub_exit);
 187
 188 int usb_phy_roothub_set_mode(struct usb_phy_roothub *phy_roothub,
 189                              enum phy_mode mode)
 190 {
 191         struct usb_phy_roothub *roothub_entry;
 192         struct list_head *head;
 193         int err;
 194
 195         if (!phy_roothub)
 196                 return 0;
 197
 198         head = &phy_roothub->list;
 199
 200         list_for_each_entry(roothub_entry, head, list) {
 201                 err = phy_set_mode(roothub_entry->phy, mode);
 202                 if (err)
 203                         goto err_out;
 204         }
 205
 206         return 0;
 207
 208 err_out:
 209         list_for_each_entry_continue_reverse(roothub_entry, head, list)
 210                 phy_power_off(roothub_entry->phy);
 211
 212         return err;
 213 }
 214 EXPORT_SYMBOL_GPL(usb_phy_roothub_set_mode);
 215
 216 int usb_phy_roothub_calibrate(struct usb_phy_roothub *phy_roothub)
 217 {
 218         struct usb_phy_roothub *roothub_entry;
 219         struct list_head *head;
 220         int err;
 221
 222         if (!phy_roothub)
 223                 return 0;
 224
 225         head = &phy_roothub->list;
 226
 227         list_for_each_entry(roothub_entry, head, list) {
 228                 err = phy_calibrate(roothub_entry->phy);
 229                 if (err)
 230                         return err;
 231         }
 232
 233         return 0;
 234 }
 235 EXPORT_SYMBOL_GPL(usb_phy_roothub_calibrate);
 236
 237 /**
 238  * usb_phy_roothub_notify_connect() - connect notification
 239  * @phy_roothub: the phy of roothub, if the host use a generic phy.
 240  * @port: the port index for connect
 241  *
 242  * If the phy needs to get connection status, the callback can be used.
 243  * Returns: %0 if successful, a negative error code otherwise
 244  */
 245 int usb_phy_roothub_notify_connect(struct usb_phy_roothub *phy_roothub, int port)
 246 {
 247         struct usb_phy_roothub *roothub_entry;
 248         struct list_head *head;
 249         int err;
 250
 251         if (!phy_roothub)
 252                 return 0;
 253
 254         head = &phy_roothub->list;
 255
 256         list_for_each_entry(roothub_entry, head, list) {
 257                 err = phy_notify_connect(roothub_entry->phy, port);
 258                 if (err)
 259                         return err;
 260         }
 261
 262         return 0;
 263 }
 264 EXPORT_SYMBOL_GPL(usb_phy_roothub_notify_connect);
 265
 266 /**
 267  * usb_phy_roothub_notify_disconnect() - disconnect notification
 268  * @phy_roothub: the phy of roothub, if the host use a generic phy.
 269  * @port: the port index for disconnect
 270  *
 271  * If the phy needs to get connection status, the callback can be used.
 272  * Returns: %0 if successful, a negative error code otherwise
 273  */
 274 int usb_phy_roothub_notify_disconnect(struct usb_phy_roothub *phy_roothub, int port)
 275 {
 276         struct usb_phy_roothub *roothub_entry;
 277         struct list_head *head;
 278         int err;
 279
 280         if (!phy_roothub)
 281                 return 0;
 282
 283         head = &phy_roothub->list;
 284
 285         list_for_each_entry(roothub_entry, head, list) {
 286                 err = phy_notify_disconnect(roothub_entry->phy, port);
 287                 if (err)
 288                         return err;
 289         }
 290
 291         return 0;
 292 }
 293 EXPORT_SYMBOL_GPL(usb_phy_roothub_notify_disconnect);
 294
 295 int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub)
 296 {
 297         struct usb_phy_roothub *roothub_entry;
 298         struct list_head *head;
 299         int err;
 300
 301         if (!phy_roothub)
 302                 return 0;
 303
 304         head = &phy_roothub->list;
 305
 306         list_for_each_entry(roothub_entry, head, list) {
 307                 err = phy_power_on(roothub_entry->phy);
 308                 if (err)
 309                         goto err_out;
 310         }
 311
 312         return 0;
 313
 314 err_out:
 315         list_for_each_entry_continue_reverse(roothub_entry, head, list)
 316                 phy_power_off(roothub_entry->phy);
 317
 318         return err;
 319 }
 320 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on);
 321
 322 void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub)
 323 {
 324         struct usb_phy_roothub *roothub_entry;
 325
 326         if (!phy_roothub)
 327                 return;
 328
 329         list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list)
 330                 phy_power_off(roothub_entry->phy);
 331 }
 332 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off);
 333
 334 int usb_phy_roothub_suspend(struct device *controller_dev,
 335                             struct usb_phy_roothub *phy_roothub)
 336 {
 337         usb_phy_roothub_power_off(phy_roothub);
 338
 339         /* keep the PHYs initialized so the device can wake up the system */
 340         if (device_may_wakeup(controller_dev))
 341                 return 0;
 342
 343         return usb_phy_roothub_exit(phy_roothub);
 344 }
 345 EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend);
 346
 347 int usb_phy_roothub_resume(struct device *controller_dev,
 348                            struct usb_phy_roothub *phy_roothub)
 349 {
 350         int err;
 351
 352         /* if the device can't wake up the system _exit was called */
 353         if (!device_may_wakeup(controller_dev)) {
 354                 err = usb_phy_roothub_init(phy_roothub);
 355                 if (err)
 356                         return err;
 357         }
 358
 359         err = usb_phy_roothub_power_on(phy_roothub);
 360
 361         /* undo _init if _power_on failed */
 362         if (err && !device_may_wakeup(controller_dev))
 363                 usb_phy_roothub_exit(phy_roothub);
 364
 365         return err;
 366 }
 367 EXPORT_SYMBOL_GPL(usb_phy_roothub_resume);