summaryrefslogtreecommitdiffstats
path: root/drivers/mfd/tps65912-spi.c
blob: 6366576a3056dcd9d49a6925ccaea97499d1df0d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
/*
 * tps65912-spi.c  --  SPI access for TI TPS65912x PMIC
 *
 * Copyright 2011 Texas Instruments Inc.
 *
 * Author: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
 *
 *  This program is free software; you can redistribute it and/or modify it
 *  under  the terms of the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the License, or (at your
 *  option) any later version.
 *
 *  This driver is based on wm8350 implementation.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/spi/spi.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tps65912.h>

static int tps65912_spi_write(struct tps65912 *tps65912, u8 addr,
							int bytes, void *src)
{
	struct spi_device *spi = tps65912->control_data;
	u8 *data = (u8 *) src;
	int ret;
	/* bit 23 is the read/write bit */
	unsigned long spi_data = 1 << 23 | addr << 15 | *data;
	struct spi_transfer xfer;
	struct spi_message msg;
	u32 tx_buf, rx_buf;

	tx_buf = spi_data;
	rx_buf = 0;

	xfer.tx_buf	= &tx_buf;
	xfer.rx_buf	= NULL;
	xfer.len	= sizeof(unsigned long);
	xfer.bits_per_word = 24;

	spi_message_init(&msg);
	spi_message_add_tail(&xfer, &msg);

	ret = spi_sync(spi, &msg);
	return ret;
}

static int tps65912_spi_read(struct tps65912 *tps65912, u8 addr,
							int bytes, void *dest)
{
	struct spi_device *spi = tps65912->control_data;
	/* bit 23 is the read/write bit */
	unsigned long spi_data = 0 << 23 | addr << 15;
	struct spi_transfer xfer;
	struct spi_message msg;
	int ret;
	u8 *data = (u8 *) dest;
	u32 tx_buf, rx_buf;

	tx_buf = spi_data;
	rx_buf = 0;

	xfer.tx_buf	= &tx_buf;
	xfer.rx_buf	= &rx_buf;
	xfer.len	= sizeof(unsigned long);
	xfer.bits_per_word = 24;

	spi_message_init(&msg);
	spi_message_add_tail(&xfer, &msg);

	if (spi == NULL)
		return 0;

	ret = spi_sync(spi, &msg);
	if (ret == 0)
		*data = (u8) (rx_buf & 0xFF);
	return ret;
}

static int tps65912_spi_probe(struct spi_device *spi)
{
	struct tps65912 *tps65912;

	tps65912 = kzalloc(sizeof(struct tps65912), GFP_KERNEL);
	if (tps65912 == NULL)
		return -ENOMEM;

	tps65912->dev = &spi->dev;
	tps65912->control_data = spi;
	tps65912->read = tps65912_spi_read;
	tps65912->write = tps65912_spi_write;

	spi_set_drvdata(spi, tps65912);

	return tps65912_device_init(tps65912);
}

static int __devexit tps65912_spi_remove(struct spi_device *spi)
{
	struct tps65912 *tps65912 = spi_get_drvdata(spi);

	tps65912_device_exit(tps65912);

	return 0;
}

static struct spi_driver tps65912_spi_driver = {
	.driver = {
		.name = "tps65912",
		.owner = THIS_MODULE,
	},
	.probe	= tps65912_spi_probe,
	.remove = tps65912_spi_remove,
};

static int __init tps65912_spi_init(void)
{
	int ret;

	ret = spi_register_driver(&tps65912_spi_driver);
	if (ret != 0)
		pr_err("Failed to register TPS65912 SPI driver: %d\n", ret);

	return 0;
}
/* init early so consumer devices can complete system boot */
subsys_initcall(tps65912_spi_init);

static void __exit tps65912_spi_exit(void)
{
	spi_unregister_driver(&tps65912_spi_driver);
}
module_exit(tps65912_spi_exit);

MODULE_AUTHOR("Margarita Olaya	<magi@slimlogic.co.uk>");
MODULE_DESCRIPTION("SPI support for TPS65912 chip family mfd");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud