/*
    bttv-gpio.c  --  gpio sub drivers

    sysfs-based sub driver interface for bttv
    mainly intented for gpio access


    Copyright (C) 1996,97,98 Ralph  Metzler (rjkm@thp.uni-koeln.de)
                           & Marcus Metzler (mocm@thp.uni-koeln.de)
    (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
    
*/

#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <asm/io.h>

#include "bttvp.h"

/* ----------------------------------------------------------------------- */
/* internal: the bttv "bus"                                                */

static int bttv_sub_bus_match(struct device *dev, struct device_driver *drv)
{
	struct bttv_sub_driver *sub = to_bttv_sub_drv(drv);
	int len = strlen(sub->wanted);

	if (0 == strncmp(dev->bus_id, sub->wanted, len))
		return 1;
	return 0;
}

struct bus_type bttv_sub_bus_type = {
	.name  = "bttv-sub",
	.match = &bttv_sub_bus_match,
};
EXPORT_SYMBOL(bttv_sub_bus_type);

static void release_sub_device(struct device *dev)
{
	struct bttv_sub_device *sub = to_bttv_sub_dev(dev);
	kfree(sub);
}

int bttv_sub_add_device(struct bttv_core *core, char *name)
{
	struct bttv_sub_device *sub;

	sub = kmalloc(sizeof(*sub),GFP_KERNEL);
	if (NULL == sub)
		return -ENOMEM;
	memset(sub,0,sizeof(*sub));

	sub->core        = core;
	sub->dev.parent  = &core->pci->dev;
	sub->dev.bus     = &bttv_sub_bus_type;
	sub->dev.release = release_sub_device;
	snprintf(sub->dev.bus_id,sizeof(sub->dev.bus_id),"%s%d",
		 name, core->nr);

	printk("bttv%d: add subdevice \"%s\"\n", core->nr, sub->dev.bus_id);
	list_add_tail(&sub->list,&core->subs);
	device_register(&sub->dev);
	return 0;
}

int bttv_sub_del_devices(struct bttv_core *core)
{
	struct bttv_sub_device *sub;
	struct list_head *item,*save;

	list_for_each_safe(item,save,&core->subs) {
		sub = list_entry(item,struct bttv_sub_device,list);
		device_unregister(&sub->dev);
	}
	return 0;
}

void bttv_gpio_irq(struct bttv_core *core)
{
	struct bttv_sub_driver *drv;
	struct bttv_sub_device *dev;
	struct list_head *item;

	list_for_each(item,&core->subs) {
		dev = list_entry(item,struct bttv_sub_device,list);
		drv = to_bttv_sub_drv(dev->dev.driver);
		if (drv && drv->gpio_irq)
			drv->gpio_irq(dev);
	}
}

/* ----------------------------------------------------------------------- */
/* external: sub-driver register/unregister                                */

int bttv_sub_register(struct bttv_sub_driver *sub, char *wanted)
{
	sub->drv.bus = &bttv_sub_bus_type;
	snprintf(sub->wanted,sizeof(sub->wanted),"%s",wanted);
	driver_register(&sub->drv);
	return 0;
}
EXPORT_SYMBOL(bttv_sub_register);

int bttv_sub_unregister(struct bttv_sub_driver *sub)
{
	driver_unregister(&sub->drv);
	return 0;
}
EXPORT_SYMBOL(bttv_sub_unregister);

/* ----------------------------------------------------------------------- */
/* external: gpio access functions                                         */

void bttv_gpio_inout(struct bttv_core *core, u32 mask, u32 outbits)
{
	struct bttv *btv = container_of(core, struct bttv, c);
	unsigned long flags;
	u32 data;

	spin_lock_irqsave(&btv->gpio_lock,flags);
	data = btread(BT848_GPIO_OUT_EN);
	data = data & ~mask;
	data = data | (mask & outbits);
	btwrite(data,BT848_GPIO_OUT_EN);
	spin_unlock_irqrestore(&btv->gpio_lock,flags);
}
EXPORT_SYMBOL(bttv_gpio_inout);

u32 bttv_gpio_read(struct bttv_core *core)
{
	struct bttv *btv = container_of(core, struct bttv, c);
	u32 value;

	value = btread(BT848_GPIO_DATA);
	return value;
}
EXPORT_SYMBOL(bttv_gpio_read);

void bttv_gpio_write(struct bttv_core *core, u32 value)
{
	struct bttv *btv = container_of(core, struct bttv, c);

	btwrite(value,BT848_GPIO_DATA);
}
EXPORT_SYMBOL(bttv_gpio_write);

void bttv_gpio_bits(struct bttv_core *core, u32 mask, u32 bits)
{
	struct bttv *btv = container_of(core, struct bttv, c);
	unsigned long flags;
	u32 data;

	spin_lock_irqsave(&btv->gpio_lock,flags);
	data = btread(BT848_GPIO_DATA);
	data = data & ~mask;
	data = data | (mask & bits);
	btwrite(data,BT848_GPIO_DATA);
	spin_unlock_irqrestore(&btv->gpio_lock,flags);
}
EXPORT_SYMBOL(bttv_gpio_bits);

/*
 * Local variables:
 * c-basic-offset: 8
 * End:
 */