sysreset_syscon.c 2.1 KB

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  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
  4. *
  5. * Derived from linux/drivers/power/reset/syscon-reboot.c:
  6. * Copyright (C) 2013, Applied Micro Circuits Corporation
  7. * Author: Feng Kan <fkan@apm.com>
  8. */
  9. #include <common.h>
  10. #include <dm.h>
  11. #include <errno.h>
  12. #include <regmap.h>
  13. #include <sysreset.h>
  14. #include <syscon.h>
  15. #include <linux/err.h>
  16. struct syscon_reboot_priv {
  17. struct regmap *regmap;
  18. unsigned int offset;
  19. unsigned int mask;
  20. unsigned int value;
  21. };
  22. static int syscon_reboot_request(struct udevice *dev, enum sysreset_t type)
  23. {
  24. struct syscon_reboot_priv *priv = dev_get_priv(dev);
  25. ulong driver_data = dev_get_driver_data(dev);
  26. if (type != driver_data)
  27. return -EPROTONOSUPPORT;
  28. regmap_update_bits(priv->regmap, priv->offset, priv->mask, priv->value);
  29. return -EINPROGRESS;
  30. }
  31. static struct sysreset_ops syscon_reboot_ops = {
  32. .request = syscon_reboot_request,
  33. };
  34. int syscon_reboot_probe(struct udevice *dev)
  35. {
  36. struct syscon_reboot_priv *priv = dev_get_priv(dev);
  37. int err;
  38. int mask_err, value_err;
  39. priv->regmap = syscon_regmap_lookup_by_phandle(dev, "regmap");
  40. if (IS_ERR(priv->regmap)) {
  41. pr_err("unable to find regmap\n");
  42. return -ENODEV;
  43. }
  44. err = dev_read_u32(dev, "offset", &priv->offset);
  45. if (err) {
  46. pr_err("unable to find offset\n");
  47. return -ENOENT;
  48. }
  49. mask_err = dev_read_u32(dev, "mask", &priv->mask);
  50. value_err = dev_read_u32(dev, "value", &priv->value);
  51. if (mask_err && value_err) {
  52. pr_err("unable to find mask and value\n");
  53. return -EINVAL;
  54. }
  55. if (value_err) {
  56. /* support old binding */
  57. priv->value = priv->mask;
  58. priv->mask = 0xffffffff;
  59. } else if (mask_err) {
  60. /* support value without mask*/
  61. priv->mask = 0xffffffff;
  62. }
  63. return 0;
  64. }
  65. static const struct udevice_id syscon_reboot_ids[] = {
  66. { .compatible = "syscon-reboot", .data = SYSRESET_COLD },
  67. { .compatible = "syscon-poweroff", .data = SYSRESET_POWER_OFF },
  68. { /* sentinel */ }
  69. };
  70. U_BOOT_DRIVER(syscon_reboot) = {
  71. .name = "syscon_reboot",
  72. .id = UCLASS_SYSRESET,
  73. .of_match = syscon_reboot_ids,
  74. .probe = syscon_reboot_probe,
  75. .priv_auto = sizeof(struct syscon_reboot_priv),
  76. .ops = &syscon_reboot_ops,
  77. };