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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
|
/* linux/drivers/spi/spi_s3c24xx_gpio.c
*
* Copyright (c) 2006 Ben Dooks
* Copyright (c) 2006 Simtec Electronics
*
* S3C24XX GPIO based SPI driver
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <asm/arch/regs-gpio.h>
#include <asm/arch/spi-gpio.h>
#include <asm/hardware.h>
struct s3c2410_spigpio {
struct spi_bitbang bitbang;
struct s3c2410_spigpio_info *info;
struct platform_device *dev;
};
static inline struct s3c2410_spigpio *spidev_to_sg(struct spi_device *spi)
{
return spi->controller_data;
}
static inline void setsck(struct spi_device *dev, int on)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
s3c2410_gpio_setpin(sg->info->pin_clk, on ? 1 : 0);
}
static inline void setmosi(struct spi_device *dev, int on)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
s3c2410_gpio_setpin(sg->info->pin_mosi, on ? 1 : 0);
}
static inline u32 getmiso(struct spi_device *dev)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
return s3c2410_gpio_getpin(sg->info->pin_miso) ? 1 : 0;
}
#define spidelay(x) ndelay(x)
#define EXPAND_BITBANG_TXRX
#include <linux/spi/spi_bitbang.h>
static u32 s3c2410_spigpio_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
}
static void s3c2410_spigpio_chipselect(struct spi_device *dev, int value)
{
struct s3c2410_spigpio *sg = spidev_to_sg(dev);
if (sg->info && sg->info->chip_select)
(sg->info->chip_select)(sg->info, value);
}
static int s3c2410_spigpio_probe(struct platform_device *dev)
{
struct s3c2410_spigpio_info *info;
struct spi_master *master;
struct s3c2410_spigpio *sp;
int ret;
int i;
master = spi_alloc_master(&dev->dev, sizeof(struct s3c2410_spigpio));
if (master == NULL) {
dev_err(&dev->dev, "failed to allocate spi master\n");
ret = -ENOMEM;
goto err;
}
sp = spi_master_get_devdata(master);
platform_set_drvdata(dev, sp);
/* copy in the plkatform data */
info = sp->info = dev->dev.platform_data;
/* setup spi bitbang adaptor */
sp->bitbang.master = spi_master_get(master);
sp->bitbang.chipselect = s3c2410_spigpio_chipselect;
sp->bitbang.txrx_word[SPI_MODE_0] = s3c2410_spigpio_txrx_mode0;
sp->bitbang.txrx_word[SPI_MODE_1] = s3c2410_spigpio_txrx_mode1;
sp->bitbang.txrx_word[SPI_MODE_2] = s3c2410_spigpio_txrx_mode2;
sp->bitbang.txrx_word[SPI_MODE_3] = s3c2410_spigpio_txrx_mode3;
/* set state of spi pins, always assume that the clock is
* available, but do check the MOSI and MISO. */
s3c2410_gpio_setpin(info->pin_clk, 0);
s3c2410_gpio_cfgpin(info->pin_clk, S3C2410_GPIO_OUTPUT);
if (info->pin_mosi < S3C2410_GPH10) {
s3c2410_gpio_setpin(info->pin_mosi, 0);
s3c2410_gpio_cfgpin(info->pin_mosi, S3C2410_GPIO_OUTPUT);
}
if (info->pin_miso != S3C2410_GPA0 && info->pin_miso < S3C2410_GPH10)
s3c2410_gpio_cfgpin(info->pin_miso, S3C2410_GPIO_INPUT);
ret = spi_bitbang_start(&sp->bitbang);
if (ret)
goto err_no_bitbang;
/* register the chips to go with the board */
for (i = 0; i < sp->info->board_size; i++) {
dev_info(&dev->dev, "registering %p: %s\n",
&sp->info->board_info[i],
sp->info->board_info[i].modalias);
sp->info->board_info[i].controller_data = sp;
spi_new_device(master, sp->info->board_info + i);
}
return 0;
err_no_bitbang:
spi_master_put(sp->bitbang.master);
err:
return ret;
}
static int s3c2410_spigpio_remove(struct platform_device *dev)
{
struct s3c2410_spigpio *sp = platform_get_drvdata(dev);
spi_bitbang_stop(&sp->bitbang);
spi_master_put(sp->bitbang.master);
return 0;
}
/* all gpio should be held over suspend/resume, so we should
* not need to deal with this
*/
#define s3c2410_spigpio_suspend NULL
#define s3c2410_spigpio_resume NULL
static struct platform_driver s3c2410_spigpio_drv = {
.probe = s3c2410_spigpio_probe,
.remove = s3c2410_spigpio_remove,
.suspend = s3c2410_spigpio_suspend,
.resume = s3c2410_spigpio_resume,
.driver = {
.name = "spi_s3c24xx_gpio",
.owner = THIS_MODULE,
},
};
static int __init s3c2410_spigpio_init(void)
{
return platform_driver_register(&s3c2410_spigpio_drv);
}
static void __exit s3c2410_spigpio_exit(void)
{
platform_driver_unregister(&s3c2410_spigpio_drv);
}
module_init(s3c2410_spigpio_init);
module_exit(s3c2410_spigpio_exit);
MODULE_DESCRIPTION("S3C24XX SPI Driver");
MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
|
