1/* 2 * AD714X CapTouch Programmable Controller driver (SPI bus) 3 * 4 * Copyright 2009 Analog Devices Inc. 5 * 6 * Licensed under the GPL-2 or later. 7 */ 8 9#include <linux/input.h> /* BUS_I2C */ 10#include <linux/module.h> 11#include <linux/spi/spi.h> 12#include <linux/types.h> 13#include "ad714x.h" 14 15#define AD714x_SPI_CMD_PREFIX 0xE000 /* bits 15:11 */ 16#define AD714x_SPI_READ BIT(10) 17 18#ifdef CONFIG_PM 19static int ad714x_spi_suspend(struct spi_device *spi, pm_message_t message) 20{ 21 return ad714x_disable(spi_get_drvdata(spi)); 22} 23 24static int ad714x_spi_resume(struct spi_device *spi) 25{ 26 return ad714x_enable(spi_get_drvdata(spi)); 27} 28#else 29# define ad714x_spi_suspend NULL 30# define ad714x_spi_resume NULL 31#endif 32 33static int ad714x_spi_read(struct device *dev, unsigned short reg, 34 unsigned short *data) 35{ 36 struct spi_device *spi = to_spi_device(dev); 37 unsigned short tx = AD714x_SPI_CMD_PREFIX | AD714x_SPI_READ | reg; 38 39 return spi_write_then_read(spi, (u8 *)&tx, 2, (u8 *)data, 2); 40} 41 42static int ad714x_spi_write(struct device *dev, unsigned short reg, 43 unsigned short data) 44{ 45 struct spi_device *spi = to_spi_device(dev); 46 unsigned short tx[2] = { 47 AD714x_SPI_CMD_PREFIX | reg, 48 data 49 }; 50 51 return spi_write(spi, (u8 *)tx, 4); 52} 53 54static int __devinit ad714x_spi_probe(struct spi_device *spi) 55{ 56 struct ad714x_chip *chip; 57 58 chip = ad714x_probe(&spi->dev, BUS_SPI, spi->irq, 59 ad714x_spi_read, ad714x_spi_write); 60 if (IS_ERR(chip)) 61 return PTR_ERR(chip); 62 63 spi_set_drvdata(spi, chip); 64 65 return 0; 66} 67 68static int __devexit ad714x_spi_remove(struct spi_device *spi) 69{ 70 struct ad714x_chip *chip = spi_get_drvdata(spi); 71 72 ad714x_remove(chip); 73 spi_set_drvdata(spi, NULL); 74 75 return 0; 76} 77 78static struct spi_driver ad714x_spi_driver = { 79 .driver = { 80 .name = "ad714x_captouch", 81 .owner = THIS_MODULE, 82 }, 83 .probe = ad714x_spi_probe, 84 .remove = __devexit_p(ad714x_spi_remove), 85 .suspend = ad714x_spi_suspend, 86 .resume = ad714x_spi_resume, 87}; 88 89static __init int ad714x_spi_init(void) 90{ 91 return spi_register_driver(&ad714x_spi_driver); 92} 93module_init(ad714x_spi_init); 94 95static __exit void ad714x_spi_exit(void) 96{ 97 spi_unregister_driver(&ad714x_spi_driver); 98} 99module_exit(ad714x_spi_exit); 100 101MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor SPI Bus Driver"); 102MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); 103MODULE_LICENSE("GPL"); 104