1/*
2 * tps65912-spi.c  --  SPI access for TI TPS65912x PMIC
3 *
4 * Copyright 2011 Texas Instruments Inc.
5 *
6 * Author: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
7 *
8 *  This program is free software; you can redistribute it and/or modify it
9 *  under  the terms of the GNU General  Public License as published by the
10 *  Free Software Foundation;  either version 2 of the License, or (at your
11 *  option) any later version.
12 *
13 *  This driver is based on wm8350 implementation.
14 */
15
16#include <linux/module.h>
17#include <linux/moduleparam.h>
18#include <linux/init.h>
19#include <linux/slab.h>
20#include <linux/gpio.h>
21#include <linux/spi/spi.h>
22#include <linux/mfd/core.h>
23#include <linux/mfd/tps65912.h>
24
25static int tps65912_spi_write(struct tps65912 *tps65912, u8 addr,
26							int bytes, void *src)
27{
28	struct spi_device *spi = tps65912->control_data;
29	u8 *data = (u8 *) src;
30	int ret;
31	/* bit 23 is the read/write bit */
32	unsigned long spi_data = 1 << 23 | addr << 15 | *data;
33	struct spi_transfer xfer;
34	struct spi_message msg;
35	u32 tx_buf;
36
37	tx_buf = spi_data;
38
39	xfer.tx_buf	= &tx_buf;
40	xfer.rx_buf	= NULL;
41	xfer.len	= sizeof(unsigned long);
42	xfer.bits_per_word = 24;
43
44	spi_message_init(&msg);
45	spi_message_add_tail(&xfer, &msg);
46
47	ret = spi_sync(spi, &msg);
48	return ret;
49}
50
51static int tps65912_spi_read(struct tps65912 *tps65912, u8 addr,
52							int bytes, void *dest)
53{
54	struct spi_device *spi = tps65912->control_data;
55	/* bit 23 is the read/write bit */
56	unsigned long spi_data = 0 << 23 | addr << 15;
57	struct spi_transfer xfer;
58	struct spi_message msg;
59	int ret;
60	u8 *data = (u8 *) dest;
61	u32 tx_buf, rx_buf;
62
63	tx_buf = spi_data;
64	rx_buf = 0;
65
66	xfer.tx_buf	= &tx_buf;
67	xfer.rx_buf	= &rx_buf;
68	xfer.len	= sizeof(unsigned long);
69	xfer.bits_per_word = 24;
70
71	spi_message_init(&msg);
72	spi_message_add_tail(&xfer, &msg);
73
74	if (spi == NULL)
75		return 0;
76
77	ret = spi_sync(spi, &msg);
78	if (ret == 0)
79		*data = (u8) (rx_buf & 0xFF);
80	return ret;
81}
82
83static int tps65912_spi_probe(struct spi_device *spi)
84{
85	struct tps65912 *tps65912;
86
87	tps65912 = devm_kzalloc(&spi->dev,
88				sizeof(struct tps65912), GFP_KERNEL);
89	if (tps65912 == NULL)
90		return -ENOMEM;
91
92	tps65912->dev = &spi->dev;
93	tps65912->control_data = spi;
94	tps65912->read = tps65912_spi_read;
95	tps65912->write = tps65912_spi_write;
96
97	spi_set_drvdata(spi, tps65912);
98
99	return tps65912_device_init(tps65912);
100}
101
102static int tps65912_spi_remove(struct spi_device *spi)
103{
104	struct tps65912 *tps65912 = spi_get_drvdata(spi);
105
106	tps65912_device_exit(tps65912);
107
108	return 0;
109}
110
111static struct spi_driver tps65912_spi_driver = {
112	.driver = {
113		.name = "tps65912",
114		.owner = THIS_MODULE,
115	},
116	.probe	= tps65912_spi_probe,
117	.remove = tps65912_spi_remove,
118};
119
120static int __init tps65912_spi_init(void)
121{
122	int ret;
123
124	ret = spi_register_driver(&tps65912_spi_driver);
125	if (ret != 0)
126		pr_err("Failed to register TPS65912 SPI driver: %d\n", ret);
127
128	return 0;
129}
130/* init early so consumer devices can complete system boot */
131subsys_initcall(tps65912_spi_init);
132
133static void __exit tps65912_spi_exit(void)
134{
135	spi_unregister_driver(&tps65912_spi_driver);
136}
137module_exit(tps65912_spi_exit);
138
139MODULE_AUTHOR("Margarita Olaya	<magi@slimlogic.co.uk>");
140MODULE_DESCRIPTION("SPI support for TPS65912 chip family mfd");
141MODULE_LICENSE("GPL");
142