diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/i2c/busses/scx200_i2c.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/i2c/busses/scx200_i2c.c')
-rw-r--r-- | drivers/i2c/busses/scx200_i2c.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/i2c/busses/scx200_i2c.c b/drivers/i2c/busses/scx200_i2c.c new file mode 100644 index 000000000000..27fbfecc414f --- /dev/null +++ b/drivers/i2c/busses/scx200_i2c.c | |||
@@ -0,0 +1,131 @@ | |||
1 | /* linux/drivers/i2c/scx200_i2c.c | ||
2 | |||
3 | Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> | ||
4 | |||
5 | National Semiconductor SCx200 I2C bus on GPIO pins | ||
6 | |||
7 | Based on i2c-velleman.c Copyright (C) 1995-96, 2000 Simon G. Vogl | ||
8 | |||
9 | This program is free software; you can redistribute it and/or modify | ||
10 | it under the terms of the GNU General Public License as published by | ||
11 | the Free Software Foundation; either version 2 of the License, or | ||
12 | (at your option) any later version. | ||
13 | |||
14 | This program is distributed in the hope that it will be useful, | ||
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
17 | GNU General Public License for more details. | ||
18 | |||
19 | You should have received a copy of the GNU General Public License | ||
20 | along with this program; if not, write to the Free Software | ||
21 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
22 | */ | ||
23 | |||
24 | #include <linux/config.h> | ||
25 | #include <linux/module.h> | ||
26 | #include <linux/errno.h> | ||
27 | #include <linux/kernel.h> | ||
28 | #include <linux/init.h> | ||
29 | #include <linux/i2c.h> | ||
30 | #include <linux/i2c-algo-bit.h> | ||
31 | #include <asm/io.h> | ||
32 | |||
33 | #include <linux/scx200_gpio.h> | ||
34 | |||
35 | #define NAME "scx200_i2c" | ||
36 | |||
37 | MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>"); | ||
38 | MODULE_DESCRIPTION("NatSemi SCx200 I2C Driver"); | ||
39 | MODULE_LICENSE("GPL"); | ||
40 | |||
41 | static int scl = CONFIG_SCx200_I2C_SCL; | ||
42 | static int sda = CONFIG_SCx200_I2C_SDA; | ||
43 | |||
44 | module_param(scl, int, 0); | ||
45 | MODULE_PARM_DESC(scl, "GPIO line for SCL"); | ||
46 | module_param(sda, int, 0); | ||
47 | MODULE_PARM_DESC(sda, "GPIO line for SDA"); | ||
48 | |||
49 | static void scx200_i2c_setscl(void *data, int state) | ||
50 | { | ||
51 | scx200_gpio_set(scl, state); | ||
52 | } | ||
53 | |||
54 | static void scx200_i2c_setsda(void *data, int state) | ||
55 | { | ||
56 | scx200_gpio_set(sda, state); | ||
57 | } | ||
58 | |||
59 | static int scx200_i2c_getscl(void *data) | ||
60 | { | ||
61 | return scx200_gpio_get(scl); | ||
62 | } | ||
63 | |||
64 | static int scx200_i2c_getsda(void *data) | ||
65 | { | ||
66 | return scx200_gpio_get(sda); | ||
67 | } | ||
68 | |||
69 | /* ------------------------------------------------------------------------ | ||
70 | * Encapsulate the above functions in the correct operations structure. | ||
71 | * This is only done when more than one hardware adapter is supported. | ||
72 | */ | ||
73 | |||
74 | static struct i2c_algo_bit_data scx200_i2c_data = { | ||
75 | NULL, | ||
76 | scx200_i2c_setsda, | ||
77 | scx200_i2c_setscl, | ||
78 | scx200_i2c_getsda, | ||
79 | scx200_i2c_getscl, | ||
80 | 10, 10, 100, /* waits, timeout */ | ||
81 | }; | ||
82 | |||
83 | static struct i2c_adapter scx200_i2c_ops = { | ||
84 | .owner = THIS_MODULE, | ||
85 | .algo_data = &scx200_i2c_data, | ||
86 | .name = "NatSemi SCx200 I2C", | ||
87 | }; | ||
88 | |||
89 | static int scx200_i2c_init(void) | ||
90 | { | ||
91 | pr_debug(NAME ": NatSemi SCx200 I2C Driver\n"); | ||
92 | |||
93 | if (!scx200_gpio_present()) { | ||
94 | printk(KERN_ERR NAME ": no SCx200 gpio pins available\n"); | ||
95 | return -ENODEV; | ||
96 | } | ||
97 | |||
98 | pr_debug(NAME ": SCL=GPIO%02u, SDA=GPIO%02u\n", scl, sda); | ||
99 | |||
100 | if (scl == -1 || sda == -1 || scl == sda) { | ||
101 | printk(KERN_ERR NAME ": scl and sda must be specified\n"); | ||
102 | return -EINVAL; | ||
103 | } | ||
104 | |||
105 | /* Configure GPIOs as open collector outputs */ | ||
106 | scx200_gpio_configure(scl, ~2, 5); | ||
107 | scx200_gpio_configure(sda, ~2, 5); | ||
108 | |||
109 | if (i2c_bit_add_bus(&scx200_i2c_ops) < 0) { | ||
110 | printk(KERN_ERR NAME ": adapter %s registration failed\n", | ||
111 | scx200_i2c_ops.name); | ||
112 | return -ENODEV; | ||
113 | } | ||
114 | |||
115 | return 0; | ||
116 | } | ||
117 | |||
118 | static void scx200_i2c_cleanup(void) | ||
119 | { | ||
120 | i2c_bit_del_bus(&scx200_i2c_ops); | ||
121 | } | ||
122 | |||
123 | module_init(scx200_i2c_init); | ||
124 | module_exit(scx200_i2c_cleanup); | ||
125 | |||
126 | /* | ||
127 | Local variables: | ||
128 | compile-command: "make -k -C ../.. SUBDIRS=drivers/i2c modules" | ||
129 | c-basic-offset: 8 | ||
130 | End: | ||
131 | */ | ||