ia64/linux-2.6.18-xen.hg

view drivers/spi/spi_s3c24xx_gpio.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /* linux/drivers/spi/spi_s3c24xx_gpio.c
2 *
3 * Copyright (c) 2006 Ben Dooks
4 * Copyright (c) 2006 Simtec Electronics
5 *
6 * S3C24XX GPIO based SPI driver
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
14 #include <linux/config.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/spinlock.h>
19 #include <linux/platform_device.h>
21 #include <linux/spi/spi.h>
22 #include <linux/spi/spi_bitbang.h>
24 #include <asm/arch/regs-gpio.h>
25 #include <asm/arch/spi-gpio.h>
26 #include <asm/arch/hardware.h>
28 struct s3c2410_spigpio {
29 struct spi_bitbang bitbang;
31 struct s3c2410_spigpio_info *info;
32 struct platform_device *dev;
33 };
35 static inline struct s3c2410_spigpio *spidev_to_sg(struct spi_device *spi)
36 {
37 return spi->controller_data;
38 }
40 static inline void setsck(struct spi_device *dev, int on)
41 {
42 struct s3c2410_spigpio *sg = spidev_to_sg(dev);
43 s3c2410_gpio_setpin(sg->info->pin_clk, on ? 1 : 0);
44 }
46 static inline void setmosi(struct spi_device *dev, int on)
47 {
48 struct s3c2410_spigpio *sg = spidev_to_sg(dev);
49 s3c2410_gpio_setpin(sg->info->pin_mosi, on ? 1 : 0);
50 }
52 static inline u32 getmiso(struct spi_device *dev)
53 {
54 struct s3c2410_spigpio *sg = spidev_to_sg(dev);
55 return s3c2410_gpio_getpin(sg->info->pin_miso) ? 1 : 0;
56 }
58 #define spidelay(x) ndelay(x)
60 #define EXPAND_BITBANG_TXRX
61 #include <linux/spi/spi_bitbang.h>
64 static u32 s3c2410_spigpio_txrx_mode0(struct spi_device *spi,
65 unsigned nsecs, u32 word, u8 bits)
66 {
67 return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
68 }
70 static u32 s3c2410_spigpio_txrx_mode1(struct spi_device *spi,
71 unsigned nsecs, u32 word, u8 bits)
72 {
73 return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
74 }
76 static void s3c2410_spigpio_chipselect(struct spi_device *dev, int value)
77 {
78 struct s3c2410_spigpio *sg = spidev_to_sg(dev);
80 if (sg->info && sg->info->chip_select)
81 (sg->info->chip_select)(sg->info, value);
82 }
84 static int s3c2410_spigpio_probe(struct platform_device *dev)
85 {
86 struct spi_master *master;
87 struct s3c2410_spigpio *sp;
88 int ret;
89 int i;
91 master = spi_alloc_master(&dev->dev, sizeof(struct s3c2410_spigpio));
92 if (master == NULL) {
93 dev_err(&dev->dev, "failed to allocate spi master\n");
94 ret = -ENOMEM;
95 goto err;
96 }
98 sp = spi_master_get_devdata(master);
100 platform_set_drvdata(dev, sp);
102 /* copy in the plkatform data */
103 sp->info = dev->dev.platform_data;
105 /* setup spi bitbang adaptor */
106 sp->bitbang.master = spi_master_get(master);
107 sp->bitbang.chipselect = s3c2410_spigpio_chipselect;
109 sp->bitbang.txrx_word[SPI_MODE_0] = s3c2410_spigpio_txrx_mode0;
110 sp->bitbang.txrx_word[SPI_MODE_1] = s3c2410_spigpio_txrx_mode1;
112 /* set state of spi pins */
113 s3c2410_gpio_setpin(sp->info->pin_clk, 0);
114 s3c2410_gpio_setpin(sp->info->pin_mosi, 0);
116 s3c2410_gpio_cfgpin(sp->info->pin_clk, S3C2410_GPIO_OUTPUT);
117 s3c2410_gpio_cfgpin(sp->info->pin_mosi, S3C2410_GPIO_OUTPUT);
118 s3c2410_gpio_cfgpin(sp->info->pin_miso, S3C2410_GPIO_INPUT);
120 ret = spi_bitbang_start(&sp->bitbang);
121 if (ret)
122 goto err_no_bitbang;
124 /* register the chips to go with the board */
126 for (i = 0; i < sp->info->board_size; i++) {
127 dev_info(&dev->dev, "registering %p: %s\n",
128 &sp->info->board_info[i],
129 sp->info->board_info[i].modalias);
131 sp->info->board_info[i].controller_data = sp;
132 spi_new_device(master, sp->info->board_info + i);
133 }
135 return 0;
137 err_no_bitbang:
138 spi_master_put(sp->bitbang.master);
139 err:
140 return ret;
142 }
144 static int s3c2410_spigpio_remove(struct platform_device *dev)
145 {
146 struct s3c2410_spigpio *sp = platform_get_drvdata(dev);
148 spi_bitbang_stop(&sp->bitbang);
149 spi_master_put(sp->bitbang.master);
151 return 0;
152 }
154 /* all gpio should be held over suspend/resume, so we should
155 * not need to deal with this
156 */
158 #define s3c2410_spigpio_suspend NULL
159 #define s3c2410_spigpio_resume NULL
162 static struct platform_driver s3c2410_spigpio_drv = {
163 .probe = s3c2410_spigpio_probe,
164 .remove = s3c2410_spigpio_remove,
165 .suspend = s3c2410_spigpio_suspend,
166 .resume = s3c2410_spigpio_resume,
167 .driver = {
168 .name = "s3c24xx-spi-gpio",
169 .owner = THIS_MODULE,
170 },
171 };
173 static int __init s3c2410_spigpio_init(void)
174 {
175 return platform_driver_register(&s3c2410_spigpio_drv);
176 }
178 static void __exit s3c2410_spigpio_exit(void)
179 {
180 platform_driver_unregister(&s3c2410_spigpio_drv);
181 }
183 module_init(s3c2410_spigpio_init);
184 module_exit(s3c2410_spigpio_exit);
186 MODULE_DESCRIPTION("S3C24XX SPI Driver");
187 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
188 MODULE_LICENSE("GPL");