drivers/media/pci/bt8xx/bttv-gpio.c

   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                 kfree(sub);
 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  */