linux/drivers/input/touchscreen/ad7879-spi.c

73 lines
1.7 KiB
C

/*
* AD7879/AD7889 touchscreen (SPI bus)
*
* Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/input.h> /* BUS_SPI */
#include <linux/pm.h>
#include <linux/spi/spi.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include "ad7879.h"
#define AD7879_DEVID 0x7A /* AD7879/AD7889 */
#define MAX_SPI_FREQ_HZ 5000000
#define AD7879_CMD_MAGIC 0xE0
#define AD7879_CMD_READ BIT(2)
static const struct regmap_config ad7879_spi_regmap_config = {
.reg_bits = 16,
.val_bits = 16,
.max_register = 15,
.read_flag_mask = AD7879_CMD_MAGIC | AD7879_CMD_READ,
.write_flag_mask = AD7879_CMD_MAGIC,
};
static int ad7879_spi_probe(struct spi_device *spi)
{
struct regmap *regmap;
/* don't exceed max specified SPI CLK frequency */
if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
dev_err(&spi->dev, "SPI CLK %d Hz?\n", spi->max_speed_hz);
return -EINVAL;
}
regmap = devm_regmap_init_spi(spi, &ad7879_spi_regmap_config);
if (IS_ERR(regmap))
return PTR_ERR(regmap);
return ad7879_probe(&spi->dev, regmap, spi->irq, BUS_SPI, AD7879_DEVID);
}
#ifdef CONFIG_OF
static const struct of_device_id ad7879_spi_dt_ids[] = {
{ .compatible = "adi,ad7879", },
{ }
};
MODULE_DEVICE_TABLE(of, ad7879_spi_dt_ids);
#endif
static struct spi_driver ad7879_spi_driver = {
.driver = {
.name = "ad7879",
.pm = &ad7879_pm_ops,
.of_match_table = of_match_ptr(ad7879_spi_dt_ids),
},
.probe = ad7879_spi_probe,
};
module_spi_driver(ad7879_spi_driver);
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("AD7879(-1) touchscreen SPI bus driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:ad7879");