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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 4 bttv-gpio.c -- gpio sub drivers5 6 sysfs-based sub driver interface for bttv7 mainly intended for gpio access8 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 ": " fmt18 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 31static int bttv_sub_bus_match(struct device *dev, const struct device_driver *drv)32{33 const 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 41static 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 49static 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 58const 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 65static void release_sub_device(struct device *dev)66{67 struct bttv_sub_device *sub = to_bttv_sub_dev(dev);68 kfree(sub);69}70 71int 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 96int 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 110int 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}116EXPORT_SYMBOL(bttv_sub_register);117 118int bttv_sub_unregister(struct bttv_sub_driver *sub)119{120 driver_unregister(&sub->drv);121 return 0;122}123EXPORT_SYMBOL(bttv_sub_unregister);124 125/* ----------------------------------------------------------------------- */126/* external: gpio access functions */127 128void 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 142u32 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 151void 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 158void 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