1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Samsung LSI S5C73M3 8M pixel camera driver
4 *
5 * Copyright (C) 2012, Samsung Electronics, Co., Ltd.
6 * Sylwester Nawrocki <s.nawrocki@samsung.com>
7 * Andrzej Hajda <a.hajda@samsung.com>
8 */
9
10#include <linux/sizes.h>
11#include <linux/delay.h>
12#include <linux/init.h>
13#include <linux/media.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/spi/spi.h>
17
18#include "s5c73m3.h"
19
20#define S5C73M3_SPI_DRV_NAME "S5C73M3-SPI"
21
22static const struct of_device_id s5c73m3_spi_ids[] = {
23	{ .compatible = "samsung,s5c73m3" },
24	{ }
25};
26MODULE_DEVICE_TABLE(of, s5c73m3_spi_ids);
27
28enum spi_direction {
29	SPI_DIR_RX,
30	SPI_DIR_TX
31};
32
33static int spi_xmit(struct spi_device *spi_dev, void *addr, const int len,
34							enum spi_direction dir)
35{
36	struct spi_message msg;
37	int r;
38	struct spi_transfer xfer = {
39		.len	= len,
40	};
41
42	if (dir == SPI_DIR_TX)
43		xfer.tx_buf = addr;
44	else
45		xfer.rx_buf = addr;
46
47	if (spi_dev == NULL) {
48		pr_err("SPI device is uninitialized\n");
49		return -ENODEV;
50	}
51
52	spi_message_init(&msg);
53	spi_message_add_tail(&xfer, &msg);
54
55	r = spi_sync(spi_dev, &msg);
56	if (r < 0)
57		dev_err(&spi_dev->dev, "%s spi_sync failed %d\n", __func__, r);
58
59	return r;
60}
61
62int s5c73m3_spi_write(struct s5c73m3 *state, const void *addr,
63		      const unsigned int len, const unsigned int tx_size)
64{
65	struct spi_device *spi_dev = state->spi_dev;
66	u32 count = len / tx_size;
67	u32 extra = len % tx_size;
68	unsigned int i, j = 0;
69	u8 padding[32];
70	int r = 0;
71
72	memset(padding, 0, sizeof(padding));
73
74	for (i = 0; i < count; i++) {
75		r = spi_xmit(spi_dev, (void *)addr + j, tx_size, SPI_DIR_TX);
76		if (r < 0)
77			return r;
78		j += tx_size;
79	}
80
81	if (extra > 0) {
82		r = spi_xmit(spi_dev, (void *)addr + j, extra, SPI_DIR_TX);
83		if (r < 0)
84			return r;
85	}
86
87	return spi_xmit(spi_dev, padding, sizeof(padding), SPI_DIR_TX);
88}
89
90int s5c73m3_spi_read(struct s5c73m3 *state, void *addr,
91		     const unsigned int len, const unsigned int tx_size)
92{
93	struct spi_device *spi_dev = state->spi_dev;
94	u32 count = len / tx_size;
95	u32 extra = len % tx_size;
96	unsigned int i, j = 0;
97	int r = 0;
98
99	for (i = 0; i < count; i++) {
100		r = spi_xmit(spi_dev, addr + j, tx_size, SPI_DIR_RX);
101		if (r < 0)
102			return r;
103		j += tx_size;
104	}
105
106	if (extra > 0)
107		return spi_xmit(spi_dev, addr + j, extra, SPI_DIR_RX);
108
109	return 0;
110}
111
112static int s5c73m3_spi_probe(struct spi_device *spi)
113{
114	int r;
115	struct s5c73m3 *state = container_of(spi->dev.driver, struct s5c73m3,
116					     spidrv.driver);
117	spi->bits_per_word = 32;
118
119	r = spi_setup(spi);
120	if (r < 0) {
121		dev_err(&spi->dev, "spi_setup() failed\n");
122		return r;
123	}
124
125	mutex_lock(&state->lock);
126	state->spi_dev = spi;
127	mutex_unlock(&state->lock);
128
129	v4l2_info(&state->sensor_sd, "S5C73M3 SPI probed successfully\n");
130	return 0;
131}
132
133static int s5c73m3_spi_remove(struct spi_device *spi)
134{
135	return 0;
136}
137
138int s5c73m3_register_spi_driver(struct s5c73m3 *state)
139{
140	struct spi_driver *spidrv = &state->spidrv;
141
142	spidrv->remove = s5c73m3_spi_remove;
143	spidrv->probe = s5c73m3_spi_probe;
144	spidrv->driver.name = S5C73M3_SPI_DRV_NAME;
145	spidrv->driver.of_match_table = s5c73m3_spi_ids;
146
147	return spi_register_driver(spidrv);
148}
149
150void s5c73m3_unregister_spi_driver(struct s5c73m3 *state)
151{
152	spi_unregister_driver(&state->spidrv);
153}
154