summaryrefslogtreecommitdiffstats
path: root/drivers/media/i2c/s5c73m3/s5c73m3-spi.c
blob: 8079e26eb5e2f7c4c5dfec7b725e5b0d061cc33e (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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
/*
 * Samsung LSI S5C73M3 8M pixel camera driver
 *
 * Copyright (C) 2012, Samsung Electronics, Co., Ltd.
 * Sylwester Nawrocki <s.nawrocki@samsung.com>
 * Andrzej Hajda <a.hajda@samsung.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/sizes.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/media.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>

#include "s5c73m3.h"

#define S5C73M3_SPI_DRV_NAME "S5C73M3-SPI"

enum spi_direction {
	SPI_DIR_RX,
	SPI_DIR_TX
};

static int spi_xmit(struct spi_device *spi_dev, void *addr, const int len,
							enum spi_direction dir)
{
	struct spi_message msg;
	int r;
	struct spi_transfer xfer = {
		.len	= len,
	};

	if (dir == SPI_DIR_TX)
		xfer.tx_buf = addr;
	else
		xfer.rx_buf = addr;

	if (spi_dev == NULL) {
		dev_err(&spi_dev->dev, "SPI device is uninitialized\n");
		return -ENODEV;
	}

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

	r = spi_sync(spi_dev, &msg);
	if (r < 0)
		dev_err(&spi_dev->dev, "%s spi_sync failed %d\n", __func__, r);

	return r;
}

int s5c73m3_spi_write(struct s5c73m3 *state, const void *addr,
		      const unsigned int len, const unsigned int tx_size)
{
	struct spi_device *spi_dev = state->spi_dev;
	u32 count = len / tx_size;
	u32 extra = len % tx_size;
	unsigned int i, j = 0;
	u8 padding[32];
	int r = 0;

	memset(padding, 0, sizeof(padding));

	for (i = 0; i < count; i++) {
		r = spi_xmit(spi_dev, (void *)addr + j, tx_size, SPI_DIR_TX);
		if (r < 0)
			return r;
		j += tx_size;
	}

	if (extra > 0) {
		r = spi_xmit(spi_dev, (void *)addr + j, extra, SPI_DIR_TX);
		if (r < 0)
			return r;
	}

	return spi_xmit(spi_dev, padding, sizeof(padding), SPI_DIR_TX);
}

int s5c73m3_spi_read(struct s5c73m3 *state, void *addr,
		     const unsigned int len, const unsigned int tx_size)
{
	struct spi_device *spi_dev = state->spi_dev;
	u32 count = len / tx_size;
	u32 extra = len % tx_size;
	unsigned int i, j = 0;
	int r = 0;

	for (i = 0; i < count; i++) {
		r = spi_xmit(spi_dev, addr + j, tx_size, SPI_DIR_RX);
		if (r < 0)
			return r;
		j += tx_size;
	}

	if (extra > 0)
		return spi_xmit(spi_dev, addr + j, extra, SPI_DIR_RX);

	return 0;
}

static int s5c73m3_spi_probe(struct spi_device *spi)
{
	int r;
	struct s5c73m3 *state = container_of(spi->dev.driver, struct s5c73m3,
					     spidrv.driver);
	spi->bits_per_word = 32;

	r = spi_setup(spi);
	if (r < 0) {
		dev_err(&spi->dev, "spi_setup() failed\n");
		return r;
	}

	mutex_lock(&state->lock);
	state->spi_dev = spi;
	mutex_unlock(&state->lock);

	v4l2_info(&state->sensor_sd, "S5C73M3 SPI probed successfully\n");
	return 0;
}

static int s5c73m3_spi_remove(struct spi_device *spi)
{
	return 0;
}

int s5c73m3_register_spi_driver(struct s5c73m3 *state)
{
	struct spi_driver *spidrv = &state->spidrv;

	spidrv->remove = s5c73m3_spi_remove;
	spidrv->probe = s5c73m3_spi_probe;
	spidrv->driver.name = S5C73M3_SPI_DRV_NAME;
	spidrv->driver.bus = &spi_bus_type;
	spidrv->driver.owner = THIS_MODULE;

	return spi_register_driver(spidrv);
}

void s5c73m3_unregister_spi_driver(struct s5c73m3 *state)
{
	spi_unregister_driver(&state->spidrv);
}