source: branches/8.09/package/w1-gpio-custom/src/w1-gpio-custom.c

Last change on this file was 10982, checked in by juhosg, 9 years ago

[package] import w1-gpio-custom driver from the Squidge (http://squidge.sourceforge.net/) project

  • Property svn:eol-style set to native
  • Property svn:keywords set to Author Date Id Revision
File size: 4.3 KB
Line 
1/*
2 *  Custom GPIO-based W1 driver
3 *
4 *  Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
5 *  Copyright (C) 2008 Bifferos <bifferos at yahoo.co.uk>
6 *
7 *  This program is free software; you can redistribute it and/or modify
8 *  it under the terms of the GNU General Public License version 2 as
9 *  published by the Free Software Foundation.
10 *
11 * ---------------------------------------------------------------------------
12 *
13 *  The behaviour of this driver can be altered by setting some parameters
14 *  from the insmod command line.
15 *
16 *  The following parameters are adjustable:
17 *
18 *      bus0    These four arguments must be arrays of
19 *      bus1    3 unsigned integers as follows:
20 *      bus2
21 *      bus3    <id>,<pin>,<od>
22 *
23 *  where:
24 *
25 *  <id>        ID to used as device_id for the corresponding bus (required)
26 *  <sda>       GPIO pin ID of data pin (required)
27 *  <od>        Pin is configured as open drain.
28 *
29 *  See include/w1-gpio.h for more information about the parameters.
30 *
31 *  If this driver is built into the kernel, you can use the following kernel
32 *  command line parameters, with the same values as the corresponding module
33 *  parameters listed above:
34 *
35 *      w1-gpio-custom.bus0
36 *      w1-gpio-custom.bus1
37 *      w1-gpio-custom.bus2
38 *      w1-gpio-custom.bus3
39 */
40
41#include <linux/kernel.h>
42#include <linux/module.h>
43#include <linux/init.h>
44#include <linux/platform_device.h>
45
46#include <linux/w1-gpio.h>
47
48#define DRV_NAME        "w1-gpio-custom"
49#define DRV_DESC        "Custom GPIO-based W1 driver"
50#define DRV_VERSION     "0.1.0"
51
52#define PFX             DRV_NAME ": "
53
54#define BUS_PARAM_ID            0
55#define BUS_PARAM_PIN           1
56#define BUS_PARAM_OD            2
57
58#define BUS_PARAM_REQUIRED      3
59#define BUS_PARAM_COUNT         3
60#define BUS_COUNT_MAX           4
61
62static unsigned int bus0[BUS_PARAM_COUNT] __initdata;
63static unsigned int bus1[BUS_PARAM_COUNT] __initdata;
64static unsigned int bus2[BUS_PARAM_COUNT] __initdata;
65static unsigned int bus3[BUS_PARAM_COUNT] __initdata;
66
67static unsigned int bus_nump[BUS_COUNT_MAX] __initdata;
68
69#define BUS_PARM_DESC " config -> id,pin,od"
70
71module_param_array(bus0, uint, &bus_nump[0], 0);
72MODULE_PARM_DESC(bus0, "bus0" BUS_PARM_DESC);
73module_param_array(bus1, uint, &bus_nump[1], 0);
74MODULE_PARM_DESC(bus1, "bus1" BUS_PARM_DESC);
75module_param_array(bus2, uint, &bus_nump[2], 0);
76MODULE_PARM_DESC(bus2, "bus2" BUS_PARM_DESC);
77module_param_array(bus3, uint, &bus_nump[3], 0);
78MODULE_PARM_DESC(bus3, "bus3" BUS_PARM_DESC);
79
80static struct platform_device *devices[BUS_COUNT_MAX];
81static unsigned int nr_devices;
82
83static void w1_gpio_custom_cleanup(void)
84{
85        int i;
86
87        for (i = 0; i < nr_devices; i++)
88                if (devices[i])
89                        platform_device_unregister(devices[i]);
90}
91
92static int __init w1_gpio_custom_add_one(unsigned int id, unsigned int *params)
93{
94        struct platform_device *pdev;
95        struct w1_gpio_platform_data pdata;
96        int err;
97
98        if (!bus_nump[id])
99                return 0;
100
101        if (bus_nump[id] < BUS_PARAM_REQUIRED) {
102                printk(KERN_ERR PFX "not enough parameters for bus%d\n", id);
103                err = -EINVAL;
104                goto err;
105        }
106
107        pdev = platform_device_alloc("w1-gpio", params[BUS_PARAM_ID]);
108        if (!pdev) {
109                err = -ENOMEM;
110                goto err;
111        }
112
113        devices[nr_devices++] = pdev;
114
115        pdata.pin = params[BUS_PARAM_PIN];
116        pdata.is_open_drain = params[BUS_PARAM_OD] ? 1:0;
117
118        err = platform_device_add_data(pdev, &pdata, sizeof(pdata));
119        if (err)
120                goto err;
121
122        err = platform_device_register(pdev);
123        if (err)
124                goto err;
125
126        return 0;
127
128err:
129        return err;
130}
131
132static int __init w1_gpio_custom_probe(void)
133{
134        int err;
135
136        nr_devices = 0;
137        printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
138
139        err = w1_gpio_custom_add_one(0, bus0);
140        if (err) goto err;
141
142        err = w1_gpio_custom_add_one(1, bus1);
143        if (err) goto err;
144
145        err = w1_gpio_custom_add_one(2, bus2);
146        if (err) goto err;
147
148        err = w1_gpio_custom_add_one(3, bus3);
149        if (err) goto err;
150
151        if (!nr_devices) {
152                printk(KERN_ERR PFX "no bus parameter(s) specified\n");
153                err = -ENODEV;
154                goto err;
155        }
156
157        return 0;
158
159err:
160        w1_gpio_custom_cleanup();
161        return err;
162}
163
164#ifdef MODULE
165static int __init w1_gpio_custom_init(void)
166{
167        return w1_gpio_custom_probe();
168}
169module_init(w1_gpio_custom_init);
170
171static void __exit w1_gpio_custom_exit(void)
172{
173        w1_gpio_custom_cleanup();
174}
175module_exit(w1_gpio_custom_exit);
176#else
177subsys_initcall(w1_gpio_custom_probe);
178#endif /* MODULE*/
179
180MODULE_LICENSE("GPL v2");
181MODULE_AUTHOR("Bifferos <bifferos at yahoo.co.uk >");
182MODULE_DESCRIPTION(DRV_DESC);
183MODULE_VERSION(DRV_VERSION);
Note: See TracBrowser for help on using the repository browser.