syscon-reboot-mode.c 2.2 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586
  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
  4. */
  5. #include <linux/init.h>
  6. #include <linux/module.h>
  7. #include <linux/kernel.h>
  8. #include <linux/of.h>
  9. #include <linux/platform_device.h>
  10. #include <linux/reboot.h>
  11. #include <linux/regmap.h>
  12. #include <linux/mfd/syscon.h>
  13. #include <linux/reboot-mode.h>
  14. struct syscon_reboot_mode {
  15. struct regmap *map;
  16. struct reboot_mode_driver reboot;
  17. u32 offset;
  18. u32 mask;
  19. };
  20. static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot,
  21. unsigned int magic)
  22. {
  23. struct syscon_reboot_mode *syscon_rbm;
  24. int ret;
  25. syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot);
  26. ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset,
  27. syscon_rbm->mask, magic);
  28. if (ret < 0)
  29. dev_err(reboot->dev, "update reboot mode bits failed\n");
  30. return ret;
  31. }
  32. static int syscon_reboot_mode_probe(struct platform_device *pdev)
  33. {
  34. int ret;
  35. struct syscon_reboot_mode *syscon_rbm;
  36. syscon_rbm = devm_kzalloc(&pdev->dev, sizeof(*syscon_rbm), GFP_KERNEL);
  37. if (!syscon_rbm)
  38. return -ENOMEM;
  39. syscon_rbm->reboot.dev = &pdev->dev;
  40. syscon_rbm->reboot.write = syscon_reboot_mode_write;
  41. syscon_rbm->mask = 0xffffffff;
  42. syscon_rbm->map = syscon_node_to_regmap(pdev->dev.parent->of_node);
  43. if (IS_ERR(syscon_rbm->map))
  44. return PTR_ERR(syscon_rbm->map);
  45. if (of_property_read_u32(pdev->dev.of_node, "offset",
  46. &syscon_rbm->offset))
  47. return -EINVAL;
  48. of_property_read_u32(pdev->dev.of_node, "mask", &syscon_rbm->mask);
  49. ret = devm_reboot_mode_register(&pdev->dev, &syscon_rbm->reboot);
  50. if (ret)
  51. dev_err(&pdev->dev, "can't register reboot mode\n");
  52. return ret;
  53. }
  54. static const struct of_device_id syscon_reboot_mode_of_match[] = {
  55. { .compatible = "syscon-reboot-mode" },
  56. {}
  57. };
  58. MODULE_DEVICE_TABLE(of, syscon_reboot_mode_of_match);
  59. static struct platform_driver syscon_reboot_mode_driver = {
  60. .probe = syscon_reboot_mode_probe,
  61. .driver = {
  62. .name = "syscon-reboot-mode",
  63. .of_match_table = syscon_reboot_mode_of_match,
  64. },
  65. };
  66. module_platform_driver(syscon_reboot_mode_driver);
  67. MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com");
  68. MODULE_DESCRIPTION("SYSCON reboot mode driver");
  69. MODULE_LICENSE("GPL v2");