uniphier-efuse.c 1.9 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * UniPhier eFuse driver
  4. *
  5. * Copyright (C) 2017 Socionext Inc.
  6. */
  7. #include <linux/device.h>
  8. #include <linux/io.h>
  9. #include <linux/module.h>
  10. #include <linux/mod_devicetable.h>
  11. #include <linux/nvmem-provider.h>
  12. #include <linux/platform_device.h>
  13. struct uniphier_efuse_priv {
  14. void __iomem *base;
  15. };
  16. static int uniphier_reg_read(void *context,
  17. unsigned int reg, void *_val, size_t bytes)
  18. {
  19. struct uniphier_efuse_priv *priv = context;
  20. u8 *val = _val;
  21. int offs;
  22. for (offs = 0; offs < bytes; offs += sizeof(u8))
  23. *val++ = readb(priv->base + reg + offs);
  24. return 0;
  25. }
  26. static int uniphier_efuse_probe(struct platform_device *pdev)
  27. {
  28. struct device *dev = &pdev->dev;
  29. struct resource *res;
  30. struct nvmem_device *nvmem;
  31. struct nvmem_config econfig = {};
  32. struct uniphier_efuse_priv *priv;
  33. priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  34. if (!priv)
  35. return -ENOMEM;
  36. res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  37. priv->base = devm_ioremap_resource(dev, res);
  38. if (IS_ERR(priv->base))
  39. return PTR_ERR(priv->base);
  40. econfig.stride = 1;
  41. econfig.word_size = 1;
  42. econfig.read_only = true;
  43. econfig.reg_read = uniphier_reg_read;
  44. econfig.size = resource_size(res);
  45. econfig.priv = priv;
  46. econfig.dev = dev;
  47. nvmem = devm_nvmem_register(dev, &econfig);
  48. return PTR_ERR_OR_ZERO(nvmem);
  49. }
  50. static const struct of_device_id uniphier_efuse_of_match[] = {
  51. { .compatible = "socionext,uniphier-efuse",},
  52. {/* sentinel */},
  53. };
  54. MODULE_DEVICE_TABLE(of, uniphier_efuse_of_match);
  55. static struct platform_driver uniphier_efuse_driver = {
  56. .probe = uniphier_efuse_probe,
  57. .driver = {
  58. .name = "uniphier-efuse",
  59. .of_match_table = uniphier_efuse_of_match,
  60. },
  61. };
  62. module_platform_driver(uniphier_efuse_driver);
  63. MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
  64. MODULE_DESCRIPTION("UniPhier eFuse driver");
  65. MODULE_LICENSE("GPL v2");