reset.c 3.3 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * Copyright (c) 2014 MediaTek Inc.
  4. */
  5. #include <linux/mfd/syscon.h>
  6. #include <linux/module.h>
  7. #include <linux/of.h>
  8. #include <linux/platform_device.h>
  9. #include <linux/regmap.h>
  10. #include <linux/reset-controller.h>
  11. #include <linux/slab.h>
  12. #include "clk-mtk.h"
  13. struct mtk_reset {
  14. struct regmap *regmap;
  15. int regofs;
  16. struct reset_controller_dev rcdev;
  17. };
  18. static int mtk_reset_assert_set_clr(struct reset_controller_dev *rcdev,
  19. unsigned long id)
  20. {
  21. struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev);
  22. unsigned int reg = data->regofs + ((id / 32) << 4);
  23. return regmap_write(data->regmap, reg, 1);
  24. }
  25. static int mtk_reset_deassert_set_clr(struct reset_controller_dev *rcdev,
  26. unsigned long id)
  27. {
  28. struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev);
  29. unsigned int reg = data->regofs + ((id / 32) << 4) + 0x4;
  30. return regmap_write(data->regmap, reg, 1);
  31. }
  32. static int mtk_reset_assert(struct reset_controller_dev *rcdev,
  33. unsigned long id)
  34. {
  35. struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev);
  36. return regmap_update_bits(data->regmap, data->regofs + ((id / 32) << 2),
  37. BIT(id % 32), ~0);
  38. }
  39. static int mtk_reset_deassert(struct reset_controller_dev *rcdev,
  40. unsigned long id)
  41. {
  42. struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev);
  43. return regmap_update_bits(data->regmap, data->regofs + ((id / 32) << 2),
  44. BIT(id % 32), 0);
  45. }
  46. static int mtk_reset(struct reset_controller_dev *rcdev,
  47. unsigned long id)
  48. {
  49. int ret;
  50. ret = mtk_reset_assert(rcdev, id);
  51. if (ret)
  52. return ret;
  53. return mtk_reset_deassert(rcdev, id);
  54. }
  55. static int mtk_reset_set_clr(struct reset_controller_dev *rcdev,
  56. unsigned long id)
  57. {
  58. int ret;
  59. ret = mtk_reset_assert_set_clr(rcdev, id);
  60. if (ret)
  61. return ret;
  62. return mtk_reset_deassert_set_clr(rcdev, id);
  63. }
  64. static const struct reset_control_ops mtk_reset_ops = {
  65. .assert = mtk_reset_assert,
  66. .deassert = mtk_reset_deassert,
  67. .reset = mtk_reset,
  68. };
  69. static const struct reset_control_ops mtk_reset_ops_set_clr = {
  70. .assert = mtk_reset_assert_set_clr,
  71. .deassert = mtk_reset_deassert_set_clr,
  72. .reset = mtk_reset_set_clr,
  73. };
  74. static void mtk_register_reset_controller_common(struct device_node *np,
  75. unsigned int num_regs, int regofs,
  76. const struct reset_control_ops *reset_ops)
  77. {
  78. struct mtk_reset *data;
  79. int ret;
  80. struct regmap *regmap;
  81. regmap = syscon_node_to_regmap(np);
  82. if (IS_ERR(regmap)) {
  83. pr_err("Cannot find regmap for %pOF: %ld\n", np,
  84. PTR_ERR(regmap));
  85. return;
  86. }
  87. data = kzalloc(sizeof(*data), GFP_KERNEL);
  88. if (!data)
  89. return;
  90. data->regmap = regmap;
  91. data->regofs = regofs;
  92. data->rcdev.owner = THIS_MODULE;
  93. data->rcdev.nr_resets = num_regs * 32;
  94. data->rcdev.ops = reset_ops;
  95. data->rcdev.of_node = np;
  96. ret = reset_controller_register(&data->rcdev);
  97. if (ret) {
  98. pr_err("could not register reset controller: %d\n", ret);
  99. kfree(data);
  100. return;
  101. }
  102. }
  103. void mtk_register_reset_controller(struct device_node *np,
  104. unsigned int num_regs, int regofs)
  105. {
  106. mtk_register_reset_controller_common(np, num_regs, regofs,
  107. &mtk_reset_ops);
  108. }
  109. void mtk_register_reset_controller_set_clr(struct device_node *np,
  110. unsigned int num_regs, int regofs)
  111. {
  112. mtk_register_reset_controller_common(np, num_regs, regofs,
  113. &mtk_reset_ops_set_clr);
  114. }