summaryrefslogtreecommitdiff
path: root/target/linux/generic-2.6/patches-2.6.24/922-w1_gpio_driver_backport.patch
blob: 12a3490ab00495fd2f7dcad3307ac775df45070b (plain)
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
Index: linux-2.6.24.7/drivers/w1/masters/Kconfig
===================================================================
--- linux-2.6.24.7.orig/drivers/w1/masters/Kconfig
+++ linux-2.6.24.7/drivers/w1/masters/Kconfig
@@ -42,5 +42,15 @@ config W1_MASTER_DS1WM
 	  in HP iPAQ devices like h5xxx, h2200, and ASIC3-based like
 	  hx4700.
 
+config W1_MASTER_GPIO
+	tristate "GPIO 1-wire busmaster"
+	depends on GENERIC_GPIO
+	help
+	  Say Y here if you want to communicate with your 1-wire devices using
+	  GPIO pins. This driver uses the GPIO API to control the wire.
+
+	  This support is also available as a module.  If so, the module
+	  will be called w1-gpio.ko.
+
 endmenu
 
Index: linux-2.6.24.7/drivers/w1/masters/Makefile
===================================================================
--- linux-2.6.24.7.orig/drivers/w1/masters/Makefile
+++ linux-2.6.24.7/drivers/w1/masters/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_W1_MASTER_MATROX)		+= matro
 obj-$(CONFIG_W1_MASTER_DS2490)		+= ds2490.o
 obj-$(CONFIG_W1_MASTER_DS2482)		+= ds2482.o
 obj-$(CONFIG_W1_MASTER_DS1WM)		+= ds1wm.o
+obj-$(CONFIG_W1_MASTER_GPIO)		+= w1-gpio.o
Index: linux-2.6.24.7/drivers/w1/masters/w1-gpio.c
===================================================================
--- /dev/null
+++ linux-2.6.24.7/drivers/w1/masters/w1-gpio.c
@@ -0,0 +1,124 @@
+/*
+ * w1-gpio - GPIO w1 bus master driver
+ *
+ * Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
+ *
+ * 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/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/w1-gpio.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+
+#include <asm/gpio.h>
+
+static void w1_gpio_write_bit_dir(void *data, u8 bit)
+{
+	struct w1_gpio_platform_data *pdata = data;
+
+	if (bit)
+		gpio_direction_input(pdata->pin);
+	else
+		gpio_direction_output(pdata->pin, 0);
+}
+
+static void w1_gpio_write_bit_val(void *data, u8 bit)
+{
+	struct w1_gpio_platform_data *pdata = data;
+
+	gpio_set_value(pdata->pin, bit);
+}
+
+static u8 w1_gpio_read_bit(void *data)
+{
+	struct w1_gpio_platform_data *pdata = data;
+
+	return gpio_get_value(pdata->pin);
+}
+
+static int __init w1_gpio_probe(struct platform_device *pdev)
+{
+	struct w1_bus_master *master;
+	struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+	int err;
+
+	if (!pdata)
+		return -ENXIO;
+
+	master = kzalloc(sizeof(struct w1_bus_master), GFP_KERNEL);
+	if (!master)
+		return -ENOMEM;
+
+	err = gpio_request(pdata->pin, "w1");
+	if (err)
+		goto free_master;
+
+	master->data = pdata;
+	master->read_bit = w1_gpio_read_bit;
+
+	if (pdata->is_open_drain) {
+		gpio_direction_output(pdata->pin, 1);
+		master->write_bit = w1_gpio_write_bit_val;
+	} else {
+		gpio_direction_input(pdata->pin);
+		master->write_bit = w1_gpio_write_bit_dir;
+	}
+
+	err = w1_add_master_device(master);
+	if (err)
+		goto free_gpio;
+
+	platform_set_drvdata(pdev, master);
+
+	return 0;
+
+ free_gpio:
+	gpio_free(pdata->pin);
+ free_master:
+	kfree(master);
+
+	return err;
+}
+
+static int __exit w1_gpio_remove(struct platform_device *pdev)
+{
+	struct w1_bus_master *master = platform_get_drvdata(pdev);
+	struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+
+	w1_remove_master_device(master);
+	gpio_free(pdata->pin);
+	kfree(master);
+
+	return 0;
+}
+
+static struct platform_driver w1_gpio_driver = {
+	.driver = {
+		.name	= "w1-gpio",
+		.owner	= THIS_MODULE,
+	},
+	.remove	= __exit_p(w1_gpio_remove),
+};
+
+static int __init w1_gpio_init(void)
+{
+	return platform_driver_probe(&w1_gpio_driver, w1_gpio_probe);
+}
+
+static void __exit w1_gpio_exit(void)
+{
+	platform_driver_unregister(&w1_gpio_driver);
+}
+
+module_init(w1_gpio_init);
+module_exit(w1_gpio_exit);
+
+MODULE_DESCRIPTION("GPIO w1 bus master driver");
+MODULE_AUTHOR("Ville Syrjala <syrjala@sci.fi>");
+MODULE_LICENSE("GPL");
Index: linux-2.6.24.7/include/linux/w1-gpio.h
===================================================================
--- /dev/null
+++ linux-2.6.24.7/include/linux/w1-gpio.h
@@ -0,0 +1,23 @@
+/*
+ * w1-gpio interface to platform code
+ *
+ * Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
+ *
+ * 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.
+ */
+#ifndef _LINUX_W1_GPIO_H
+#define _LINUX_W1_GPIO_H
+
+/**
+ * struct w1_gpio_platform_data - Platform-dependent data for w1-gpio
+ * @pin: GPIO pin to use
+ * @is_open_drain: GPIO pin is configured as open drain
+ */
+struct w1_gpio_platform_data {
+	unsigned int pin;
+	unsigned int is_open_drain:1;
+};
+
+#endif /* _LINUX_W1_GPIO_H */