reset-mediatek.c 2.3 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. /*
  3. * Copyright (C) 2018 MediaTek Inc.
  4. *
  5. * Author: Ryder Lee <ryder.lee@mediatek.com>
  6. * Weijie Gao <weijie.gao@mediatek.com>
  7. */
  8. #include <common.h>
  9. #include <dm.h>
  10. #include <log.h>
  11. #include <malloc.h>
  12. #include <dm/lists.h>
  13. #include <regmap.h>
  14. #include <reset-uclass.h>
  15. #include <syscon.h>
  16. #include <dm/device-internal.h>
  17. #include <linux/bitops.h>
  18. #include <linux/err.h>
  19. struct mediatek_reset_priv {
  20. struct regmap *regmap;
  21. u32 regofs;
  22. u32 nr_resets;
  23. };
  24. static int mediatek_reset_request(struct reset_ctl *reset_ctl)
  25. {
  26. return 0;
  27. }
  28. static int mediatek_reset_free(struct reset_ctl *reset_ctl)
  29. {
  30. return 0;
  31. }
  32. static int mediatek_reset_assert(struct reset_ctl *reset_ctl)
  33. {
  34. struct mediatek_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  35. int id = reset_ctl->id;
  36. if (id >= priv->nr_resets)
  37. return -EINVAL;
  38. return regmap_update_bits(priv->regmap,
  39. priv->regofs + ((id / 32) << 2), BIT(id % 32), BIT(id % 32));
  40. }
  41. static int mediatek_reset_deassert(struct reset_ctl *reset_ctl)
  42. {
  43. struct mediatek_reset_priv *priv = dev_get_priv(reset_ctl->dev);
  44. int id = reset_ctl->id;
  45. if (id >= priv->nr_resets)
  46. return -EINVAL;
  47. return regmap_update_bits(priv->regmap,
  48. priv->regofs + ((id / 32) << 2), BIT(id % 32), 0);
  49. }
  50. struct reset_ops mediatek_reset_ops = {
  51. .request = mediatek_reset_request,
  52. .rfree = mediatek_reset_free,
  53. .rst_assert = mediatek_reset_assert,
  54. .rst_deassert = mediatek_reset_deassert,
  55. };
  56. static int mediatek_reset_probe(struct udevice *dev)
  57. {
  58. struct mediatek_reset_priv *priv = dev_get_priv(dev);
  59. if (!priv->regofs && !priv->nr_resets)
  60. return -EINVAL;
  61. priv->regmap = syscon_node_to_regmap(dev_ofnode(dev));
  62. if (IS_ERR(priv->regmap))
  63. return PTR_ERR(priv->regmap);
  64. return 0;
  65. }
  66. int mediatek_reset_bind(struct udevice *pdev, u32 regofs, u32 num_regs)
  67. {
  68. struct udevice *rst_dev;
  69. struct mediatek_reset_priv *priv;
  70. int ret;
  71. ret = device_bind_driver_to_node(pdev, "mediatek_reset", "reset",
  72. dev_ofnode(pdev), &rst_dev);
  73. if (ret)
  74. return ret;
  75. priv = malloc(sizeof(struct mediatek_reset_priv));
  76. priv->regofs = regofs;
  77. priv->nr_resets = num_regs * 32;
  78. dev_set_priv(rst_dev, priv);
  79. return 0;
  80. }
  81. U_BOOT_DRIVER(mediatek_reset) = {
  82. .name = "mediatek_reset",
  83. .id = UCLASS_RESET,
  84. .probe = mediatek_reset_probe,
  85. .ops = &mediatek_reset_ops,
  86. .priv_auto = sizeof(struct mediatek_reset_priv),
  87. };