/drivers/input/misc/ad714x-spi.c

https://bitbucket.org/ndreys/linux-sunxi · C · 102 lines · 75 code · 20 blank · 7 comment · 1 complexity · 28b9a18e4c68d94fabbb118d4aa080b2 MD5 · raw file 

    

  1. /*
    2. 

  2.  * AD714X CapTouch Programmable Controller driver (SPI bus)
    3. 

  3.  *
    4. 

  4.  * Copyright 2009 Analog Devices Inc.
    5. 

  5.  *
    6. 

  6.  * Licensed under the GPL-2 or later.
    7. 

  7.  */
    8. 

  8. 

  9. #include <linux/input.h>	/* BUS_I2C */
    10. 

  10. #include <linux/module.h>
    11. 

  11. #include <linux/spi/spi.h>
    12. 

  12. #include <linux/pm.h>
    13. 

  13. #include <linux/types.h>
    14. 

  14. #include "ad714x.h"
    15. 

  15. 

  16. #define AD714x_SPI_CMD_PREFIX      0xE000   /* bits 15:11 */
    17. 

  17. #define AD714x_SPI_READ            BIT(10)
    18. 

  18. 

  19. #ifdef CONFIG_PM
    20. 

  20. static int ad714x_spi_suspend(struct device *dev)
    21. 

  21. {
    22. 

  22. 	return ad714x_disable(spi_get_drvdata(to_spi_device(dev)));
    23. 

  23. }
    24. 

  24. 

  25. static int ad714x_spi_resume(struct device *dev)
    26. 

  26. {
    27. 

  27. 	return ad714x_enable(spi_get_drvdata(to_spi_device(dev)));
    28. 

  28. }
    29. 

  29. #endif
    30. 

  30. 

  31. static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);
    32. 

  32. 

  33. static int ad714x_spi_read(struct device *dev, unsigned short reg,
    34. 

  34. 		unsigned short *data)
    35. 

  35. {
    36. 

  36. 	struct spi_device *spi = to_spi_device(dev);
    37. 

  37. 	unsigned short tx = AD714x_SPI_CMD_PREFIX | AD714x_SPI_READ | reg;
    38. 

  38. 

  39. 	return spi_write_then_read(spi, (u8 *)&tx, 2, (u8 *)data, 2);
    40. 

  40. }
    41. 

  41. 

  42. static int ad714x_spi_write(struct device *dev, unsigned short reg,
    43. 

  43. 		unsigned short data)
    44. 

  44. {
    45. 

  45. 	struct spi_device *spi = to_spi_device(dev);
    46. 

  46. 	unsigned short tx[2] = {
    47. 

  47. 		AD714x_SPI_CMD_PREFIX | reg,
    48. 

  48. 		data
    49. 

  49. 	};
    50. 

  50. 

  51. 	return spi_write(spi, (u8 *)tx, 4);
    52. 

  52. }
    53. 

  53. 

  54. static int __devinit ad714x_spi_probe(struct spi_device *spi)
    55. 

  55. {
    56. 

  56. 	struct ad714x_chip *chip;
    57. 

  57. 

  58. 	chip = ad714x_probe(&spi->dev, BUS_SPI, spi->irq,
    59. 

  59. 			    ad714x_spi_read, ad714x_spi_write);
    60. 

  60. 	if (IS_ERR(chip))
    61. 

  61. 		return PTR_ERR(chip);
    62. 

  62. 

  63. 	spi_set_drvdata(spi, chip);
    64. 

  64. 

  65. 	return 0;
    66. 

  66. }
    67. 

  67. 

  68. static int __devexit ad714x_spi_remove(struct spi_device *spi)
    69. 

  69. {
    70. 

  70. 	struct ad714x_chip *chip = spi_get_drvdata(spi);
    71. 

  71. 

  72. 	ad714x_remove(chip);
    73. 

  73. 	spi_set_drvdata(spi, NULL);
    74. 

  74. 

  75. 	return 0;
    76. 

  76. }
    77. 

  77. 

  78. static struct spi_driver ad714x_spi_driver = {
    79. 

  79. 	.driver = {
    80. 

  80. 		.name	= "ad714x_captouch",
    81. 

  81. 		.owner	= THIS_MODULE,
    82. 

  82. 		.pm	= &ad714x_spi_pm,
    83. 

  83. 	},
    84. 

  84. 	.probe		= ad714x_spi_probe,
    85. 

  85. 	.remove		= __devexit_p(ad714x_spi_remove),
    86. 

  86. };
    87. 

  87. 

  88. static __init int ad714x_spi_init(void)
    89. 

  89. {
    90. 

  90. 	return spi_register_driver(&ad714x_spi_driver);
    91. 

  91. }
    92. 

  92. module_init(ad714x_spi_init);
    93. 

  93. 

  94. static __exit void ad714x_spi_exit(void)
    95. 

  95. {
    96. 

  96. 	spi_unregister_driver(&ad714x_spi_driver);
    97. 

  97. }
    98. 

  98. module_exit(ad714x_spi_exit);
    99. 

  99. 

  100. MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor SPI Bus Driver");
    101. 

  101. MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
    102. 

  102. MODULE_LICENSE("GPL");
    103.