repeater.c 4.1 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182
  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * Copyright (c) 2021-2023, Qualcomm Innovation Center, Inc. All rights reserved.
  4. */
  5. #include <linux/device.h>
  6. #include <linux/err.h>
  7. #include <linux/export.h>
  8. #include <linux/kernel.h>
  9. #include <linux/module.h>
  10. #include <linux/of.h>
  11. #include <linux/usb/repeater.h>
  12. static LIST_HEAD(repeater_list);
  13. static DEFINE_SPINLOCK(repeater_lock);
  14. void usb_put_repeater(struct usb_repeater *r)
  15. {
  16. if (r) {
  17. put_device(r->dev);
  18. if (r->dev->driver && r->dev->driver->owner)
  19. module_put(r->dev->driver->owner);
  20. }
  21. }
  22. EXPORT_SYMBOL(usb_put_repeater);
  23. static struct usb_repeater *of_usb_find_repeater(struct device_node *node)
  24. {
  25. struct usb_repeater *r;
  26. if (!of_device_is_available(node))
  27. return ERR_PTR(-ENODEV);
  28. list_for_each_entry(r, &repeater_list, head) {
  29. if (node != r->dev->of_node)
  30. continue;
  31. return r;
  32. }
  33. return ERR_PTR(-EPROBE_DEFER);
  34. }
  35. static void devm_usb_repeater_release_by_node(struct device *dev, void *res)
  36. {
  37. usb_put_repeater(res);
  38. }
  39. struct usb_repeater *devm_usb_get_repeater_by_node(struct device *dev,
  40. struct device_node *node)
  41. {
  42. struct usb_repeater *r = ERR_PTR(-ENOMEM);
  43. struct usb_repeater *r_devm;
  44. unsigned long flags;
  45. r_devm = devres_alloc(devm_usb_repeater_release_by_node,
  46. sizeof(*r_devm), GFP_KERNEL);
  47. if (!r_devm) {
  48. dev_dbg(dev, "failed to allocate memory for r_devm\n");
  49. return r;
  50. }
  51. spin_lock_irqsave(&repeater_lock, flags);
  52. r = of_usb_find_repeater(node);
  53. if (IS_ERR(r)) {
  54. devres_free(r_devm);
  55. goto err0;
  56. }
  57. if (!try_module_get(r->dev->driver->owner)) {
  58. r = ERR_PTR(-ENODEV);
  59. devres_free(r_devm);
  60. goto err0;
  61. }
  62. devres_add(dev, r_devm);
  63. get_device(r->dev);
  64. err0:
  65. spin_unlock_irqrestore(&repeater_lock, flags);
  66. return r;
  67. }
  68. EXPORT_SYMBOL(devm_usb_get_repeater_by_node);
  69. struct usb_repeater *devm_usb_get_repeater_by_phandle(struct device *dev,
  70. const char *phandle, u8 index)
  71. {
  72. struct device_node *node;
  73. struct usb_repeater *r;
  74. if (!dev->of_node) {
  75. dev_dbg(dev, "device does not have a device node entry\n");
  76. return ERR_PTR(-EINVAL);
  77. }
  78. node = of_parse_phandle(dev->of_node, phandle, index);
  79. if (!node) {
  80. dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle,
  81. dev->of_node);
  82. return ERR_PTR(-ENODEV);
  83. }
  84. r = devm_usb_get_repeater_by_node(dev, node);
  85. of_node_put(node);
  86. return r;
  87. }
  88. EXPORT_SYMBOL(devm_usb_get_repeater_by_phandle);
  89. struct usb_repeater *usb_get_repeater_by_node(struct device_node *node)
  90. {
  91. struct usb_repeater *r = ERR_PTR(-ENODEV);
  92. unsigned long flags;
  93. spin_lock_irqsave(&repeater_lock, flags);
  94. r = of_usb_find_repeater(node);
  95. spin_unlock_irqrestore(&repeater_lock, flags);
  96. return r;
  97. }
  98. EXPORT_SYMBOL(usb_get_repeater_by_node);
  99. struct usb_repeater *usb_get_repeater_by_phandle(struct device *dev,
  100. const char *phandle, u8 index)
  101. {
  102. struct device_node *node;
  103. struct usb_repeater *r;
  104. if (!dev->of_node) {
  105. dev_dbg(dev, "device does not have a device node entry\n");
  106. return ERR_PTR(-EINVAL);
  107. }
  108. node = of_parse_phandle(dev->of_node, phandle, index);
  109. if (!node) {
  110. dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle,
  111. dev->of_node);
  112. return ERR_PTR(-ENODEV);
  113. }
  114. r = usb_get_repeater_by_node(node);
  115. of_node_put(node);
  116. return r;
  117. }
  118. EXPORT_SYMBOL(usb_get_repeater_by_phandle);
  119. /**
  120. * usb_add_repeater_dev - Add repeater device
  121. * @r: repeater device available
  122. *
  123. * It shall used by any USB repeater driver to register
  124. * device to allow USB PHY driver to get access to it
  125. * for invoking repeater specific operations.
  126. */
  127. int usb_add_repeater_dev(struct usb_repeater *r)
  128. {
  129. if (!r || !r->dev) {
  130. pr_err("no repeater device\n");
  131. return -EINVAL;
  132. }
  133. spin_lock(&repeater_lock);
  134. list_add_tail(&r->head, &repeater_list);
  135. spin_unlock(&repeater_lock);
  136. return 0;
  137. }
  138. EXPORT_SYMBOL(usb_add_repeater_dev);
  139. /**
  140. * usb_remove_repeater_dev - remove repeater device
  141. * @r: USB repeater device to remove from repeater list
  142. */
  143. void usb_remove_repeater_dev(struct usb_repeater *r)
  144. {
  145. unsigned long flags;
  146. spin_lock_irqsave(&repeater_lock, flags);
  147. if (r)
  148. list_del(&r->head);
  149. spin_unlock_irqrestore(&repeater_lock, flags);
  150. }
  151. EXPORT_SYMBOL(usb_remove_repeater_dev);
  152. MODULE_DESCRIPTION("USB repeater framework");
  153. MODULE_LICENSE("GPL");