via_aux.h

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/*
 * Copyright 2011 Florian Tobias Schandinat <[email protected]>
 *
 * 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, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; 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.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
/*
 * infrastructure for devices connected via I2C
 */

#ifndef __VIA_AUX_H__
#define __VIA_AUX_H__


#include <linux/list.h>
#include <linux/i2c.h>
#include <linux/fb.h>


struct via_aux_bus {
    struct i2c_adapter *adap;   /* the I2C device to access the bus */
    struct list_head drivers;   /* drivers for devices on this bus */
};

struct via_aux_drv {
    struct list_head chain;     /* chain to support multiple drivers */

    struct via_aux_bus *bus;    /* the I2C bus used */
    u8 addr;            /* the I2C slave address */

    const char *name;   /* human readable name of the driver */
    void *data;     /* private data of this driver */

    void (*cleanup)(struct via_aux_drv *drv);
    const struct fb_videomode* (*get_preferred_mode)
        (struct via_aux_drv *drv);
};


struct via_aux_bus *via_aux_probe(struct i2c_adapter *adap);
void via_aux_free(struct via_aux_bus *bus);
const struct fb_videomode *via_aux_get_preferred_mode(struct via_aux_bus *bus);


static inline bool via_aux_add(struct via_aux_drv *drv)
{
    struct via_aux_drv *data = kmalloc(sizeof(*data), GFP_KERNEL);

    if (!data)
        return false;

    *data = *drv;
    list_add_tail(&data->chain, &data->bus->drivers);
    return true;
}

static inline bool via_aux_read(struct via_aux_drv *drv, u8 start, u8 *buf,
    u8 len)
{
    struct i2c_msg msg[2] = {
        {.addr = drv->addr, .flags = 0, .len = 1, .buf = &start},
        {.addr = drv->addr, .flags = I2C_M_RD, .len = len, .buf = buf} };

    return i2c_transfer(drv->bus->adap, msg, 2) == 2;
}


/* probe functions of existing drivers - should only be called in via_aux.c */
void via_aux_ch7301_probe(struct via_aux_bus *bus);
void via_aux_edid_probe(struct via_aux_bus *bus);
void via_aux_sii164_probe(struct via_aux_bus *bus);
void via_aux_vt1636_probe(struct via_aux_bus *bus);
void via_aux_vt1632_probe(struct via_aux_bus *bus);
void via_aux_vt1631_probe(struct via_aux_bus *bus);
void via_aux_vt1625_probe(struct via_aux_bus *bus);
void via_aux_vt1622_probe(struct via_aux_bus *bus);
void via_aux_vt1621_probe(struct via_aux_bus *bus);


#endif /* __VIA_AUX_H__ */