diff options
Diffstat (limited to 'drivers/input/misc/ad714x-spi.c')
-rw-r--r-- | drivers/input/misc/ad714x-spi.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c new file mode 100644 index 0000000..7f8dedf --- /dev/null +++ b/drivers/input/misc/ad714x-spi.c @@ -0,0 +1,103 @@ +/* + * AD714X CapTouch Programmable Controller driver (SPI bus) + * + * Copyright 2009 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/input.h> /* BUS_I2C */ +#include <linux/module.h> +#include <linux/spi/spi.h> +#include <linux/types.h> +#include "ad714x.h" + +#define AD714x_SPI_CMD_PREFIX 0xE000 /* bits 15:11 */ +#define AD714x_SPI_READ BIT(10) + +#ifdef CONFIG_PM +static int ad714x_spi_suspend(struct spi_device *spi, pm_message_t message) +{ + return ad714x_disable(spi_get_drvdata(spi)); +} + +static int ad714x_spi_resume(struct spi_device *spi) +{ + return ad714x_enable(spi_get_drvdata(spi)); +} +#else +# define ad714x_spi_suspend NULL +# define ad714x_spi_resume NULL +#endif + +static int ad714x_spi_read(struct device *dev, unsigned short reg, + unsigned short *data) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned short tx = AD714x_SPI_CMD_PREFIX | AD714x_SPI_READ | reg; + + return spi_write_then_read(spi, (u8 *)&tx, 2, (u8 *)data, 2); +} + +static int ad714x_spi_write(struct device *dev, unsigned short reg, + unsigned short data) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned short tx[2] = { + AD714x_SPI_CMD_PREFIX | reg, + data + }; + + return spi_write(spi, (u8 *)tx, 4); +} + +static int __devinit ad714x_spi_probe(struct spi_device *spi) +{ + struct ad714x_chip *chip; + + chip = ad714x_probe(&spi->dev, BUS_SPI, spi->irq, + ad714x_spi_read, ad714x_spi_write); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + spi_set_drvdata(spi, chip); + + return 0; +} + +static int __devexit ad714x_spi_remove(struct spi_device *spi) +{ + struct ad714x_chip *chip = spi_get_drvdata(spi); + + ad714x_remove(chip); + spi_set_drvdata(spi, NULL); + + return 0; +} + +static struct spi_driver ad714x_spi_driver = { + .driver = { + .name = "ad714x_captouch", + .owner = THIS_MODULE, + }, + .probe = ad714x_spi_probe, + .remove = __devexit_p(ad714x_spi_remove), + .suspend = ad714x_spi_suspend, + .resume = ad714x_spi_resume, +}; + +static __init int ad714x_spi_init(void) +{ + return spi_register_driver(&ad714x_spi_driver); +} +module_init(ad714x_spi_init); + +static __exit void ad714x_spi_exit(void) +{ + spi_unregister_driver(&ad714x_spi_driver); +} +module_exit(ad714x_spi_exit); + +MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor SPI Bus Driver"); +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_LICENSE("GPL"); |