root/lm-sensors/trunk/kernel/busses/i2c-voodoo3.c @ 2772

/*
    voodoo3.c - Part of lm_sensors, Linux kernel modules for hardware
              monitoring
    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>,
    Philip Edelbrock <phil@netroedge.com>,
    Ralph Metzler <rjkm@thp.uni-koeln.de>, and
    Mark D. Studebaker <mdsxyz123@yahoo.com>
    
    Based on code written by Ralph Metzler <rjkm@thp.uni-koeln.de> and
    Simon Vogl

    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.
*/

/* This interfaces to the I2C bus of the Voodoo3 to gain access to
    the BT869 and possibly other I2C devices. */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/param.h>  /* for HZ */
#include "version.h"

MODULE_LICENSE("GPL");

/* the only registers we use */
#define REG     0x78
#define REG2    0x70

/* bit locations in the register */
#define DDC_ENAB        0x00040000
#define DDC_SCL_OUT     0x00080000
#define DDC_SDA_OUT     0x00100000
#define DDC_SCL_IN      0x00200000
#define DDC_SDA_IN      0x00400000
#define I2C_ENAB        0x00800000
#define I2C_SCL_OUT     0x01000000
#define I2C_SDA_OUT     0x02000000
#define I2C_SCL_IN      0x04000000
#define I2C_SDA_IN      0x08000000

/* initialization states */
#define INIT2   0x2
#define INIT3   0x4

/* delays */
#define CYCLE_DELAY     10
#define TIMEOUT         (HZ / 2)


static void config_v3(struct pci_dev *dev);

static unsigned long ioaddr;

/* The voo GPIO registers don't have individual masks for each bit
   so we always have to read before writing. */

static void bit_vooi2c_setscl(void *data, int val)
{
        unsigned int r;
        r = readl(ioaddr + REG);
        if(val)
                r |= I2C_SCL_OUT;
        else
                r &= ~I2C_SCL_OUT;
        writel(r, ioaddr + REG);
        readl(ioaddr + REG);    /* flush posted write */
}

static void bit_vooi2c_setsda(void *data, int val)
{
        unsigned int r;
        r = readl(ioaddr + REG);
        if(val)
                r |= I2C_SDA_OUT;
        else
                r &= ~I2C_SDA_OUT;
        writel(r, ioaddr + REG);
        readl(ioaddr + REG);    /* flush posted write */
}

/* The GPIO pins are open drain, so the pins always remain outputs.
   We rely on the i2c-algo-bit routines to set the pins high before
   reading the input from other chips. */

static int bit_vooi2c_getscl(void *data)
{
        return (0 != (readl(ioaddr + REG) & I2C_SCL_IN));
}

static int bit_vooi2c_getsda(void *data)
{
        return (0 != (readl(ioaddr + REG) & I2C_SDA_IN));
}

static void bit_vooddc_setscl(void *data, int val)
{
        unsigned int r;
        r = readl(ioaddr + REG);
        if(val)
                r |= DDC_SCL_OUT;
        else
                r &= ~DDC_SCL_OUT;
        writel(r, ioaddr + REG);
        readl(ioaddr + REG);    /* flush posted write */
}

static void bit_vooddc_setsda(void *data, int val)
{
        unsigned int r;
        r = readl(ioaddr + REG);
        if(val)
                r |= DDC_SDA_OUT;
        else
                r &= ~DDC_SDA_OUT;
        writel(r, ioaddr + REG);
        readl(ioaddr + REG);    /* flush posted write */
}

static int bit_vooddc_getscl(void *data)
{
        return (0 != (readl(ioaddr + REG) & DDC_SCL_IN));
}

static int bit_vooddc_getsda(void *data)
{
        return (0 != (readl(ioaddr + REG) & DDC_SDA_IN));
}


/* Configures the chip */

void config_v3(struct pci_dev *dev)
{
        unsigned int cadr;

        /* map Voodoo3 memory */
        cadr = dev->resource[0].start;
        cadr &= PCI_BASE_ADDRESS_MEM_MASK;
        ioaddr = (unsigned long)ioremap_nocache(cadr, 0x1000);
        if(ioaddr) {
                writel(0x8160, ioaddr + REG2);
                writel(0xcffc0020, ioaddr + REG);
                printk("i2c-voodoo3: Using Banshee/Voodoo3 at 0x%lx\n", ioaddr);
        }
}

static void voodoo3_inc(struct i2c_adapter *adapter)
{
#ifdef MODULE
        MOD_INC_USE_COUNT;
#endif
}

void voodoo3_dec(struct i2c_adapter *adapter)
{
#ifdef MODULE
        MOD_DEC_USE_COUNT;
#endif
}

static struct i2c_algo_bit_data voo_i2c_bit_data = {
        .setsda         = bit_vooi2c_setsda,
        .setscl         = bit_vooi2c_setscl,
        .getsda         = bit_vooi2c_getsda,
        .getscl         = bit_vooi2c_getscl,
        .udelay         = CYCLE_DELAY,
        .mdelay         = CYCLE_DELAY,
        .timeout        = TIMEOUT
};

static struct i2c_adapter voodoo3_i2c_adapter = {
        .name           = "I2C Voodoo3/Banshee adapter",
        .id             = I2C_HW_B_VOO,
        .algo_data      = &voo_i2c_bit_data,
        .inc_use        = voodoo3_inc,
        .dec_use        = voodoo3_dec,
};

static struct i2c_algo_bit_data voo_ddc_bit_data = {
        .setsda         = bit_vooddc_setsda,
        .setscl         = bit_vooddc_setscl,
        .getsda         = bit_vooddc_getsda,
        .getscl         = bit_vooddc_getscl,
        .udelay         = CYCLE_DELAY,
        .mdelay         = CYCLE_DELAY,
        .timeout        = TIMEOUT
};

static struct i2c_adapter voodoo3_ddc_adapter = {
        .name           = "DDC Voodoo3/Banshee adapter",
        .id             = I2C_HW_B_VOO,
        .algo_data      = &voo_ddc_bit_data,
        .inc_use        = voodoo3_inc,
        .dec_use        = voodoo3_dec,
};


static struct pci_device_id voodoo3_ids[] __devinitdata = {
        {
                .vendor =       PCI_VENDOR_ID_3DFX,
                .device =       PCI_DEVICE_ID_3DFX_VOODOO3,
                .subvendor =    PCI_ANY_ID,
                .subdevice =    PCI_ANY_ID,
        },
        {
                .vendor =       PCI_VENDOR_ID_3DFX,
                .device =       PCI_DEVICE_ID_3DFX_BANSHEE,
                .subvendor =    PCI_ANY_ID,
                .subdevice =    PCI_ANY_ID,
        },
        { 0, }
};

static int __devinit voodoo3_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
        int retval;

        printk("voodoo3: in probe\n");
        config_v3(dev);
        retval = i2c_bit_add_bus(&voodoo3_i2c_adapter);
        if(retval)
                return retval;
        retval = i2c_bit_add_bus(&voodoo3_ddc_adapter);
        if(retval)
                i2c_bit_del_bus(&voodoo3_i2c_adapter);
        return retval;
}

static void __devexit voodoo3_remove(struct pci_dev *dev)
{
        i2c_bit_del_bus(&voodoo3_i2c_adapter);
        i2c_bit_del_bus(&voodoo3_ddc_adapter);
}


/* Don't register driver to avoid driver conflicts */
/*
static struct pci_driver voodoo3_driver = {
        .name           = "voodoo3 smbus",
        .id_table       = voodoo3_ids,
        .probe          = voodoo3_probe,
        .remove         = __devexit_p(voodoo3_remove),
};
*/

static int __init i2c_voodoo3_init(void)
{
        struct pci_dev *dev;
        const struct pci_device_id *id;

        printk("i2c-voodoo3.o version %s (%s)\n", LM_VERSION, LM_DATE);
/*
        return pci_module_init(&voodoo3_driver);
*/
        pci_for_each_dev(dev) {
                id = pci_match_device(voodoo3_ids, dev);
                if(id)
                        if(voodoo3_probe(dev, id) >= 0)
                                return 0;
        }
        return -ENODEV;
}


static void __exit i2c_voodoo3_exit(void)
{
/*
        pci_unregister_driver(&voodoo3_driver);
*/
        voodoo3_remove(NULL);
        iounmap((void *)ioaddr);
}


MODULE_AUTHOR
    ("Frodo Looijaard <frodol@dds.nl>, Philip Edelbrock <phil@netroedge.com>, Ralph Metzler <rjkm@thp.uni-koeln.de>, and Mark D. Studebaker <mdsxyz123@yahoo.com>");
MODULE_DESCRIPTION("Voodoo3 I2C/SMBus driver");

module_init(i2c_voodoo3_init);
module_exit(i2c_voodoo3_exit);