led_gpio.c 2.7 KB

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  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * Copyright (c) 2015 Google, Inc
  4. * Written by Simon Glass <sjg@chromium.org>
  5. */
  6. #include <common.h>
  7. #include <dm.h>
  8. #include <errno.h>
  9. #include <led.h>
  10. #include <asm/gpio.h>
  11. #include <dm/lists.h>
  12. struct led_gpio_priv {
  13. struct gpio_desc gpio;
  14. };
  15. static int gpio_led_set_state(struct udevice *dev, enum led_state_t state)
  16. {
  17. struct led_gpio_priv *priv = dev_get_priv(dev);
  18. int ret;
  19. if (!dm_gpio_is_valid(&priv->gpio))
  20. return -EREMOTEIO;
  21. switch (state) {
  22. case LEDST_OFF:
  23. case LEDST_ON:
  24. break;
  25. case LEDST_TOGGLE:
  26. ret = dm_gpio_get_value(&priv->gpio);
  27. if (ret < 0)
  28. return ret;
  29. state = !ret;
  30. break;
  31. default:
  32. return -ENOSYS;
  33. }
  34. return dm_gpio_set_value(&priv->gpio, state);
  35. }
  36. static enum led_state_t gpio_led_get_state(struct udevice *dev)
  37. {
  38. struct led_gpio_priv *priv = dev_get_priv(dev);
  39. int ret;
  40. if (!dm_gpio_is_valid(&priv->gpio))
  41. return -EREMOTEIO;
  42. ret = dm_gpio_get_value(&priv->gpio);
  43. if (ret < 0)
  44. return ret;
  45. return ret ? LEDST_ON : LEDST_OFF;
  46. }
  47. static int led_gpio_probe(struct udevice *dev)
  48. {
  49. struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
  50. struct led_gpio_priv *priv = dev_get_priv(dev);
  51. int ret;
  52. /* Ignore the top-level LED node */
  53. if (!uc_plat->label)
  54. return 0;
  55. ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
  56. if (ret)
  57. return ret;
  58. return 0;
  59. }
  60. static int led_gpio_remove(struct udevice *dev)
  61. {
  62. /*
  63. * The GPIO driver may have already been removed. We will need to
  64. * address this more generally.
  65. */
  66. #ifndef CONFIG_SANDBOX
  67. struct led_gpio_priv *priv = dev_get_priv(dev);
  68. if (dm_gpio_is_valid(&priv->gpio))
  69. dm_gpio_free(dev, &priv->gpio);
  70. #endif
  71. return 0;
  72. }
  73. static int led_gpio_bind(struct udevice *parent)
  74. {
  75. struct udevice *dev;
  76. ofnode node;
  77. int ret;
  78. dev_for_each_subnode(node, parent) {
  79. struct led_uc_plat *uc_plat;
  80. const char *label;
  81. label = ofnode_read_string(node, "label");
  82. if (!label) {
  83. debug("%s: node %s has no label\n", __func__,
  84. ofnode_get_name(node));
  85. return -EINVAL;
  86. }
  87. ret = device_bind_driver_to_node(parent, "gpio_led",
  88. ofnode_get_name(node),
  89. node, &dev);
  90. if (ret)
  91. return ret;
  92. uc_plat = dev_get_uclass_platdata(dev);
  93. uc_plat->label = label;
  94. }
  95. return 0;
  96. }
  97. static const struct led_ops gpio_led_ops = {
  98. .set_state = gpio_led_set_state,
  99. .get_state = gpio_led_get_state,
  100. };
  101. static const struct udevice_id led_gpio_ids[] = {
  102. { .compatible = "gpio-leds" },
  103. { }
  104. };
  105. U_BOOT_DRIVER(led_gpio) = {
  106. .name = "gpio_led",
  107. .id = UCLASS_LED,
  108. .of_match = led_gpio_ids,
  109. .ops = &gpio_led_ops,
  110. .priv_auto_alloc_size = sizeof(struct led_gpio_priv),
  111. .bind = led_gpio_bind,
  112. .probe = led_gpio_probe,
  113. .remove = led_gpio_remove,
  114. };