regmap-spi.c 2.4 KB

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  1. /*
  2. * Register map access API - SPI support
  3. *
  4. * Copyright 2011 Wolfson Microelectronics plc
  5. *
  6. * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  7. *
  8. * This program is free software; you can redistribute it and/or modify
  9. * it under the terms of the GNU General Public License version 2 as
  10. * published by the Free Software Foundation.
  11. */
  12. #include <linux/regmap.h>
  13. #include <linux/spi/spi.h>
  14. #include <linux/init.h>
  15. #include <linux/module.h>
  16. static int regmap_spi_write(struct device *dev, const void *data, size_t count)
  17. {
  18. struct spi_device *spi = to_spi_device(dev);
  19. return spi_write(spi, data, count);
  20. }
  21. static int regmap_spi_gather_write(struct device *dev,
  22. const void *reg, size_t reg_len,
  23. const void *val, size_t val_len)
  24. {
  25. struct spi_device *spi = to_spi_device(dev);
  26. struct spi_message m;
  27. struct spi_transfer t[2] = { { .tx_buf = reg, .len = reg_len, },
  28. { .tx_buf = val, .len = val_len, }, };
  29. spi_message_init(&m);
  30. spi_message_add_tail(&t[0], &m);
  31. spi_message_add_tail(&t[1], &m);
  32. return spi_sync(spi, &m);
  33. }
  34. static int regmap_spi_read(struct device *dev,
  35. const void *reg, size_t reg_size,
  36. void *val, size_t val_size)
  37. {
  38. struct spi_device *spi = to_spi_device(dev);
  39. return spi_write_then_read(spi, reg, reg_size, val, val_size);
  40. }
  41. static struct regmap_bus regmap_spi = {
  42. .write = regmap_spi_write,
  43. .gather_write = regmap_spi_gather_write,
  44. .read = regmap_spi_read,
  45. .read_flag_mask = 0x80,
  46. };
  47. /**
  48. * regmap_init_spi(): Initialise register map
  49. *
  50. * @spi: Device that will be interacted with
  51. * @config: Configuration for register map
  52. *
  53. * The return value will be an ERR_PTR() on error or a valid pointer to
  54. * a struct regmap.
  55. */
  56. struct regmap *regmap_init_spi(struct spi_device *spi,
  57. const struct regmap_config *config)
  58. {
  59. return regmap_init(&spi->dev, &regmap_spi, config);
  60. }
  61. EXPORT_SYMBOL_GPL(regmap_init_spi);
  62. /**
  63. * devm_regmap_init_spi(): Initialise register map
  64. *
  65. * @spi: Device that will be interacted with
  66. * @config: Configuration for register map
  67. *
  68. * The return value will be an ERR_PTR() on error or a valid pointer
  69. * to a struct regmap. The map will be automatically freed by the
  70. * device management code.
  71. */
  72. struct regmap *devm_regmap_init_spi(struct spi_device *spi,
  73. const struct regmap_config *config)
  74. {
  75. return devm_regmap_init(&spi->dev, &regmap_spi, config);
  76. }
  77. EXPORT_SYMBOL_GPL(devm_regmap_init_spi);
  78. MODULE_LICENSE("GPL");