1/*
2 * Driver for the Analog Devices digital potentiometers (SPI bus)
3 *
4 * Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9#include <linux/spi/spi.h>
10#include <linux/module.h>
11
12#include "ad525x_dpot.h"
13
14/* SPI bus functions */
15static int write8(void *client, u8 val)
16{
17	u8 data = val;
18
19	return spi_write(client, &data, 1);
20}
21
22static int write16(void *client, u8 reg, u8 val)
23{
24	u8 data[2] = {reg, val};
25
26	return spi_write(client, data, 2);
27}
28
29static int write24(void *client, u8 reg, u16 val)
30{
31	u8 data[3] = {reg, val >> 8, val};
32
33	return spi_write(client, data, 3);
34}
35
36static int read8(void *client)
37{
38	int ret;
39	u8 data;
40
41	ret = spi_read(client, &data, 1);
42	if (ret < 0)
43		return ret;
44
45	return data;
46}
47
48static int read16(void *client, u8 reg)
49{
50	int ret;
51	u8 buf_rx[2];
52
53	write16(client, reg, 0);
54	ret = spi_read(client, buf_rx, 2);
55	if (ret < 0)
56		return ret;
57
58	return (buf_rx[0] << 8) |  buf_rx[1];
59}
60
61static int read24(void *client, u8 reg)
62{
63	int ret;
64	u8 buf_rx[3];
65
66	write24(client, reg, 0);
67	ret = spi_read(client, buf_rx, 3);
68	if (ret < 0)
69		return ret;
70
71	return (buf_rx[1] << 8) |  buf_rx[2];
72}
73
74static const struct ad_dpot_bus_ops bops = {
75	.read_d8	= read8,
76	.read_r8d8	= read16,
77	.read_r8d16	= read24,
78	.write_d8	= write8,
79	.write_r8d8	= write16,
80	.write_r8d16	= write24,
81};
82static int ad_dpot_spi_probe(struct spi_device *spi)
83{
84	struct ad_dpot_bus_data bdata = {
85		.client = spi,
86		.bops = &bops,
87	};
88
89	return ad_dpot_probe(&spi->dev, &bdata,
90			     spi_get_device_id(spi)->driver_data,
91			     spi_get_device_id(spi)->name);
92}
93
94static int ad_dpot_spi_remove(struct spi_device *spi)
95{
96	return ad_dpot_remove(&spi->dev);
97}
98
99static const struct spi_device_id ad_dpot_spi_id[] = {
100	{"ad5160", AD5160_ID},
101	{"ad5161", AD5161_ID},
102	{"ad5162", AD5162_ID},
103	{"ad5165", AD5165_ID},
104	{"ad5200", AD5200_ID},
105	{"ad5201", AD5201_ID},
106	{"ad5203", AD5203_ID},
107	{"ad5204", AD5204_ID},
108	{"ad5206", AD5206_ID},
109	{"ad5207", AD5207_ID},
110	{"ad5231", AD5231_ID},
111	{"ad5232", AD5232_ID},
112	{"ad5233", AD5233_ID},
113	{"ad5235", AD5235_ID},
114	{"ad5260", AD5260_ID},
115	{"ad5262", AD5262_ID},
116	{"ad5263", AD5263_ID},
117	{"ad5290", AD5290_ID},
118	{"ad5291", AD5291_ID},
119	{"ad5292", AD5292_ID},
120	{"ad5293", AD5293_ID},
121	{"ad7376", AD7376_ID},
122	{"ad8400", AD8400_ID},
123	{"ad8402", AD8402_ID},
124	{"ad8403", AD8403_ID},
125	{"adn2850", ADN2850_ID},
126	{"ad5270", AD5270_ID},
127	{"ad5271", AD5271_ID},
128	{}
129};
130MODULE_DEVICE_TABLE(spi, ad_dpot_spi_id);
131
132static struct spi_driver ad_dpot_spi_driver = {
133	.driver = {
134		.name	= "ad_dpot",
135	},
136	.probe		= ad_dpot_spi_probe,
137	.remove		= ad_dpot_spi_remove,
138	.id_table	= ad_dpot_spi_id,
139};
140
141module_spi_driver(ad_dpot_spi_driver);
142
143MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
144MODULE_DESCRIPTION("digital potentiometer SPI bus driver");
145MODULE_LICENSE("GPL");
146MODULE_ALIAS("spi:ad_dpot");
147