// SPDX-License-Identifier: GPL-2.0-or-later /* * AD7879/AD7889 touchscreen (SPI bus) * * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc. */ #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");