72 lines
1.7 KiB
C
72 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* AD7879/AD7889 touchscreen (SPI bus)
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*
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* Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
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*/
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#include <linux/input.h> /* BUS_SPI */
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#include <linux/pm.h>
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#include <linux/spi/spi.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/regmap.h>
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#include "ad7879.h"
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#define AD7879_DEVID 0x7A /* AD7879/AD7889 */
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#define MAX_SPI_FREQ_HZ 5000000
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#define AD7879_CMD_MAGIC 0xE0
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#define AD7879_CMD_READ BIT(2)
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static const struct regmap_config ad7879_spi_regmap_config = {
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.reg_bits = 16,
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.val_bits = 16,
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.max_register = 15,
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.read_flag_mask = AD7879_CMD_MAGIC | AD7879_CMD_READ,
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.write_flag_mask = AD7879_CMD_MAGIC,
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};
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static int ad7879_spi_probe(struct spi_device *spi)
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{
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struct regmap *regmap;
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/* don't exceed max specified SPI CLK frequency */
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if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
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dev_err(&spi->dev, "SPI CLK %d Hz?\n", spi->max_speed_hz);
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return -EINVAL;
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}
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regmap = devm_regmap_init_spi(spi, &ad7879_spi_regmap_config);
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if (IS_ERR(regmap))
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return PTR_ERR(regmap);
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return ad7879_probe(&spi->dev, regmap, spi->irq, BUS_SPI, AD7879_DEVID);
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}
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#ifdef CONFIG_OF
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static const struct of_device_id ad7879_spi_dt_ids[] = {
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{ .compatible = "adi,ad7879", },
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{ }
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};
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MODULE_DEVICE_TABLE(of, ad7879_spi_dt_ids);
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#endif
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static struct spi_driver ad7879_spi_driver = {
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.driver = {
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.name = "ad7879",
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.pm = &ad7879_pm_ops,
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.of_match_table = of_match_ptr(ad7879_spi_dt_ids),
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},
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.probe = ad7879_spi_probe,
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};
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module_spi_driver(ad7879_spi_driver);
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MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
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MODULE_DESCRIPTION("AD7879(-1) touchscreen SPI bus driver");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("spi:ad7879");
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