1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3
4 bttv-gpio.c -- gpio sub drivers
5
6 sysfs-based sub driver interface for bttv
7 mainly intended for gpio access
8
9
10 Copyright (C) 1996,97,98 Ralph Metzler (rjkm@thp.uni-koeln.de)
11 & Marcus Metzler (mocm@thp.uni-koeln.de)
12 (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>
13
14
15 */
16
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/delay.h>
22 #include <linux/device.h>
23 #include <linux/slab.h>
24 #include <asm/io.h>
25
26 #include "bttvp.h"
27
28 /* ----------------------------------------------------------------------- */
29 /* internal: the bttv "bus" */
30
bttv_sub_bus_match(struct device * dev,struct device_driver * drv)31 static int bttv_sub_bus_match(struct device *dev, struct device_driver *drv)
32 {
33 struct bttv_sub_driver *sub = to_bttv_sub_drv(drv);
34 int len = strlen(sub->wanted);
35
36 if (0 == strncmp(dev_name(dev), sub->wanted, len))
37 return 1;
38 return 0;
39 }
40
bttv_sub_probe(struct device * dev)41 static int bttv_sub_probe(struct device *dev)
42 {
43 struct bttv_sub_device *sdev = to_bttv_sub_dev(dev);
44 struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver);
45
46 return sub->probe ? sub->probe(sdev) : -ENODEV;
47 }
48
bttv_sub_remove(struct device * dev)49 static void bttv_sub_remove(struct device *dev)
50 {
51 struct bttv_sub_device *sdev = to_bttv_sub_dev(dev);
52 struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver);
53
54 if (sub->remove)
55 sub->remove(sdev);
56 }
57
58 struct bus_type bttv_sub_bus_type = {
59 .name = "bttv-sub",
60 .match = &bttv_sub_bus_match,
61 .probe = bttv_sub_probe,
62 .remove = bttv_sub_remove,
63 };
64
release_sub_device(struct device * dev)65 static void release_sub_device(struct device *dev)
66 {
67 struct bttv_sub_device *sub = to_bttv_sub_dev(dev);
68 kfree(sub);
69 }
70
bttv_sub_add_device(struct bttv_core * core,char * name)71 int bttv_sub_add_device(struct bttv_core *core, char *name)
72 {
73 struct bttv_sub_device *sub;
74 int err;
75
76 sub = kzalloc(sizeof(*sub),GFP_KERNEL);
77 if (NULL == sub)
78 return -ENOMEM;
79
80 sub->core = core;
81 sub->dev.parent = &core->pci->dev;
82 sub->dev.bus = &bttv_sub_bus_type;
83 sub->dev.release = release_sub_device;
84 dev_set_name(&sub->dev, "%s%d", name, core->nr);
85
86 err = device_register(&sub->dev);
87 if (0 != err) {
88 put_device(&sub->dev);
89 return err;
90 }
91 pr_info("%d: add subdevice \"%s\"\n", core->nr, dev_name(&sub->dev));
92 list_add_tail(&sub->list,&core->subs);
93 return 0;
94 }
95
bttv_sub_del_devices(struct bttv_core * core)96 int bttv_sub_del_devices(struct bttv_core *core)
97 {
98 struct bttv_sub_device *sub, *save;
99
100 list_for_each_entry_safe(sub, save, &core->subs, list) {
101 list_del(&sub->list);
102 device_unregister(&sub->dev);
103 }
104 return 0;
105 }
106
107 /* ----------------------------------------------------------------------- */
108 /* external: sub-driver register/unregister */
109
bttv_sub_register(struct bttv_sub_driver * sub,char * wanted)110 int bttv_sub_register(struct bttv_sub_driver *sub, char *wanted)
111 {
112 sub->drv.bus = &bttv_sub_bus_type;
113 snprintf(sub->wanted,sizeof(sub->wanted),"%s",wanted);
114 return driver_register(&sub->drv);
115 }
116 EXPORT_SYMBOL(bttv_sub_register);
117
bttv_sub_unregister(struct bttv_sub_driver * sub)118 int bttv_sub_unregister(struct bttv_sub_driver *sub)
119 {
120 driver_unregister(&sub->drv);
121 return 0;
122 }
123 EXPORT_SYMBOL(bttv_sub_unregister);
124
125 /* ----------------------------------------------------------------------- */
126 /* external: gpio access functions */
127
bttv_gpio_inout(struct bttv_core * core,u32 mask,u32 outbits)128 void bttv_gpio_inout(struct bttv_core *core, u32 mask, u32 outbits)
129 {
130 struct bttv *btv = container_of(core, struct bttv, c);
131 unsigned long flags;
132 u32 data;
133
134 spin_lock_irqsave(&btv->gpio_lock,flags);
135 data = btread(BT848_GPIO_OUT_EN);
136 data = data & ~mask;
137 data = data | (mask & outbits);
138 btwrite(data,BT848_GPIO_OUT_EN);
139 spin_unlock_irqrestore(&btv->gpio_lock,flags);
140 }
141
bttv_gpio_read(struct bttv_core * core)142 u32 bttv_gpio_read(struct bttv_core *core)
143 {
144 struct bttv *btv = container_of(core, struct bttv, c);
145 u32 value;
146
147 value = btread(BT848_GPIO_DATA);
148 return value;
149 }
150
bttv_gpio_write(struct bttv_core * core,u32 value)151 void bttv_gpio_write(struct bttv_core *core, u32 value)
152 {
153 struct bttv *btv = container_of(core, struct bttv, c);
154
155 btwrite(value,BT848_GPIO_DATA);
156 }
157
bttv_gpio_bits(struct bttv_core * core,u32 mask,u32 bits)158 void bttv_gpio_bits(struct bttv_core *core, u32 mask, u32 bits)
159 {
160 struct bttv *btv = container_of(core, struct bttv, c);
161 unsigned long flags;
162 u32 data;
163
164 spin_lock_irqsave(&btv->gpio_lock,flags);
165 data = btread(BT848_GPIO_DATA);
166 data = data & ~mask;
167 data = data | (mask & bits);
168 btwrite(data,BT848_GPIO_DATA);
169 spin_unlock_irqrestore(&btv->gpio_lock,flags);
170 }
171