xref: /linux/drivers/media/pci/bt8xx/bttv-gpio.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2 
3     bttv-gpio.c  --  gpio sub drivers
4 
5     sysfs-based sub driver interface for bttv
6     mainly intended for gpio access
7 
8 
9     Copyright (C) 1996,97,98 Ralph  Metzler (rjkm@thp.uni-koeln.de)
10 			   & Marcus Metzler (mocm@thp.uni-koeln.de)
11     (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>
12 
13     This program is free software; you can redistribute it and/or modify
14     it under the terms of the GNU General Public License as published by
15     the Free Software Foundation; either version 2 of the License, or
16     (at your option) any later version.
17 
18     This program is distributed in the hope that it will be useful,
19     but WITHOUT ANY WARRANTY; without even the implied warranty of
20     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21     GNU General Public License for more details.
22 
23     You should have received a copy of the GNU General Public License
24     along with this program; if not, write to the Free Software
25     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 
27 */
28 
29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30 
31 #include <linux/module.h>
32 #include <linux/init.h>
33 #include <linux/delay.h>
34 #include <linux/device.h>
35 #include <linux/slab.h>
36 #include <asm/io.h>
37 
38 #include "bttvp.h"
39 
40 /* ----------------------------------------------------------------------- */
41 /* internal: the bttv "bus"                                                */
42 
43 static int bttv_sub_bus_match(struct device *dev, struct device_driver *drv)
44 {
45 	struct bttv_sub_driver *sub = to_bttv_sub_drv(drv);
46 	int len = strlen(sub->wanted);
47 
48 	if (0 == strncmp(dev_name(dev), sub->wanted, len))
49 		return 1;
50 	return 0;
51 }
52 
53 static int bttv_sub_probe(struct device *dev)
54 {
55 	struct bttv_sub_device *sdev = to_bttv_sub_dev(dev);
56 	struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver);
57 
58 	return sub->probe ? sub->probe(sdev) : -ENODEV;
59 }
60 
61 static int bttv_sub_remove(struct device *dev)
62 {
63 	struct bttv_sub_device *sdev = to_bttv_sub_dev(dev);
64 	struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver);
65 
66 	if (sub->remove)
67 		sub->remove(sdev);
68 	return 0;
69 }
70 
71 struct bus_type bttv_sub_bus_type = {
72 	.name   = "bttv-sub",
73 	.match  = &bttv_sub_bus_match,
74 	.probe  = bttv_sub_probe,
75 	.remove = bttv_sub_remove,
76 };
77 
78 static void release_sub_device(struct device *dev)
79 {
80 	struct bttv_sub_device *sub = to_bttv_sub_dev(dev);
81 	kfree(sub);
82 }
83 
84 int bttv_sub_add_device(struct bttv_core *core, char *name)
85 {
86 	struct bttv_sub_device *sub;
87 	int err;
88 
89 	sub = kzalloc(sizeof(*sub),GFP_KERNEL);
90 	if (NULL == sub)
91 		return -ENOMEM;
92 
93 	sub->core        = core;
94 	sub->dev.parent  = &core->pci->dev;
95 	sub->dev.bus     = &bttv_sub_bus_type;
96 	sub->dev.release = release_sub_device;
97 	dev_set_name(&sub->dev, "%s%d", name, core->nr);
98 
99 	err = device_register(&sub->dev);
100 	if (0 != err) {
101 		put_device(&sub->dev);
102 		return err;
103 	}
104 	pr_info("%d: add subdevice \"%s\"\n", core->nr, dev_name(&sub->dev));
105 	list_add_tail(&sub->list,&core->subs);
106 	return 0;
107 }
108 
109 int bttv_sub_del_devices(struct bttv_core *core)
110 {
111 	struct bttv_sub_device *sub, *save;
112 
113 	list_for_each_entry_safe(sub, save, &core->subs, list) {
114 		list_del(&sub->list);
115 		device_unregister(&sub->dev);
116 	}
117 	return 0;
118 }
119 
120 /* ----------------------------------------------------------------------- */
121 /* external: sub-driver register/unregister                                */
122 
123 int bttv_sub_register(struct bttv_sub_driver *sub, char *wanted)
124 {
125 	sub->drv.bus = &bttv_sub_bus_type;
126 	snprintf(sub->wanted,sizeof(sub->wanted),"%s",wanted);
127 	return driver_register(&sub->drv);
128 }
129 EXPORT_SYMBOL(bttv_sub_register);
130 
131 int bttv_sub_unregister(struct bttv_sub_driver *sub)
132 {
133 	driver_unregister(&sub->drv);
134 	return 0;
135 }
136 EXPORT_SYMBOL(bttv_sub_unregister);
137 
138 /* ----------------------------------------------------------------------- */
139 /* external: gpio access functions                                         */
140 
141 void bttv_gpio_inout(struct bttv_core *core, u32 mask, u32 outbits)
142 {
143 	struct bttv *btv = container_of(core, struct bttv, c);
144 	unsigned long flags;
145 	u32 data;
146 
147 	spin_lock_irqsave(&btv->gpio_lock,flags);
148 	data = btread(BT848_GPIO_OUT_EN);
149 	data = data & ~mask;
150 	data = data | (mask & outbits);
151 	btwrite(data,BT848_GPIO_OUT_EN);
152 	spin_unlock_irqrestore(&btv->gpio_lock,flags);
153 }
154 
155 u32 bttv_gpio_read(struct bttv_core *core)
156 {
157 	struct bttv *btv = container_of(core, struct bttv, c);
158 	u32 value;
159 
160 	value = btread(BT848_GPIO_DATA);
161 	return value;
162 }
163 
164 void bttv_gpio_write(struct bttv_core *core, u32 value)
165 {
166 	struct bttv *btv = container_of(core, struct bttv, c);
167 
168 	btwrite(value,BT848_GPIO_DATA);
169 }
170 
171 void bttv_gpio_bits(struct bttv_core *core, u32 mask, u32 bits)
172 {
173 	struct bttv *btv = container_of(core, struct bttv, c);
174 	unsigned long flags;
175 	u32 data;
176 
177 	spin_lock_irqsave(&btv->gpio_lock,flags);
178 	data = btread(BT848_GPIO_DATA);
179 	data = data & ~mask;
180 	data = data | (mask & bits);
181 	btwrite(data,BT848_GPIO_DATA);
182 	spin_unlock_irqrestore(&btv->gpio_lock,flags);
183 }
184 
185 /*
186  * Local variables:
187  * c-basic-offset: 8
188  * End:
189  */
190