blob: 50e88984680032ab89ff6811ed65dabd325da7f0 [file] [log] [blame]
Thomas Gleixner80503b22019-05-24 12:04:09 +02001// SPDX-License-Identifier: GPL-2.0-or-later
Mike Frysinger4397c982010-06-30 01:40:52 -07002/*
3 * AD7879/AD7889 touchscreen (SPI bus)
4 *
5 * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
Mike Frysinger4397c982010-06-30 01:40:52 -07006 */
7
8#include <linux/input.h> /* BUS_SPI */
Mark Brownc7848c82011-01-20 22:48:44 -08009#include <linux/pm.h>
Mike Frysinger4397c982010-06-30 01:40:52 -070010#include <linux/spi/spi.h>
Paul Gortmakerd2d84422011-07-03 13:53:48 -040011#include <linux/module.h>
Stefan Agnerfa6e3ca2016-03-08 10:35:24 -080012#include <linux/of.h>
Dmitry Torokhov404a24c2017-02-16 23:22:38 -080013#include <linux/regmap.h>
Mike Frysinger4397c982010-06-30 01:40:52 -070014
15#include "ad7879.h"
16
17#define AD7879_DEVID 0x7A /* AD7879/AD7889 */
18
19#define MAX_SPI_FREQ_HZ 5000000
Mike Frysinger4397c982010-06-30 01:40:52 -070020
Dmitry Torokhov404a24c2017-02-16 23:22:38 -080021#define AD7879_CMD_MAGIC 0xE0
22#define AD7879_CMD_READ BIT(2)
Mike Frysinger4397c982010-06-30 01:40:52 -070023
Dmitry Torokhov404a24c2017-02-16 23:22:38 -080024static const struct regmap_config ad7879_spi_regmap_config = {
25 .reg_bits = 16,
26 .val_bits = 16,
27 .max_register = 15,
28 .read_flag_mask = AD7879_CMD_MAGIC | AD7879_CMD_READ,
29 .write_flag_mask = AD7879_CMD_MAGIC,
Mike Frysinger4397c982010-06-30 01:40:52 -070030};
31
Bill Pemberton5298cc42012-11-23 21:38:25 -080032static int ad7879_spi_probe(struct spi_device *spi)
Mike Frysinger4397c982010-06-30 01:40:52 -070033{
Dmitry Torokhov404a24c2017-02-16 23:22:38 -080034 struct regmap *regmap;
Mike Frysinger4397c982010-06-30 01:40:52 -070035
36 /* don't exceed max specified SPI CLK frequency */
37 if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
38 dev_err(&spi->dev, "SPI CLK %d Hz?\n", spi->max_speed_hz);
39 return -EINVAL;
40 }
41
Dmitry Torokhov404a24c2017-02-16 23:22:38 -080042 regmap = devm_regmap_init_spi(spi, &ad7879_spi_regmap_config);
43 if (IS_ERR(regmap))
44 return PTR_ERR(regmap);
45
Dmitry Torokhov4e340252017-02-28 11:43:52 -080046 return ad7879_probe(&spi->dev, regmap, spi->irq, BUS_SPI, AD7879_DEVID);
Mike Frysinger4397c982010-06-30 01:40:52 -070047}
48
Stefan Agnerfa6e3ca2016-03-08 10:35:24 -080049#ifdef CONFIG_OF
50static const struct of_device_id ad7879_spi_dt_ids[] = {
51 { .compatible = "adi,ad7879", },
52 { }
53};
54MODULE_DEVICE_TABLE(of, ad7879_spi_dt_ids);
55#endif
56
Mike Frysinger4397c982010-06-30 01:40:52 -070057static struct spi_driver ad7879_spi_driver = {
58 .driver = {
59 .name = "ad7879",
Dmitry Torokhov8672bd92011-11-14 00:32:09 -080060 .pm = &ad7879_pm_ops,
Stefan Agnerfa6e3ca2016-03-08 10:35:24 -080061 .of_match_table = of_match_ptr(ad7879_spi_dt_ids),
Mike Frysinger4397c982010-06-30 01:40:52 -070062 },
63 .probe = ad7879_spi_probe,
Mike Frysinger4397c982010-06-30 01:40:52 -070064};
65
Axel Linca839222012-03-16 23:05:26 -070066module_spi_driver(ad7879_spi_driver);
Mike Frysinger4397c982010-06-30 01:40:52 -070067
Michael Hennerich2581e5d2017-02-22 10:34:20 -080068MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
Mike Frysinger4397c982010-06-30 01:40:52 -070069MODULE_DESCRIPTION("AD7879(-1) touchscreen SPI bus driver");
70MODULE_LICENSE("GPL");
71MODULE_ALIAS("spi:ad7879");