drivers/media/video/cx231xx/cx231xx-i2c.c

/*
   cx231xx-i2c.c - driver for Conexant Cx23100/101/102 USB video capture devices

   Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
        Based on em28xx driver
        Based on Cx23885 driver

   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/kernel.h>
#include <linux/usb.h>
#include <linux/i2c.h>
#include <media/v4l2-common.h>
#include <media/tuner.h>

#include "cx231xx.h"


/* ----------------------------------------------------------- */

static unsigned int i2c_scan;
module_param(i2c_scan, int, 0444);
MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");

static unsigned int i2c_debug;
module_param(i2c_debug, int, 0644);
MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");


#define dprintk1(lvl, fmt, args...)			\
do {							\
	if (i2c_debug >= lvl) {				\
	printk(fmt, ##args);				\
      }							\
} while (0)

#define dprintk2(lvl, fmt, args...)			\
do {							\
	if (i2c_debug >= lvl) {				\
		printk(KERN_DEBUG "%s at %s: " fmt,	\
		       dev->name, __func__ , ##args);	\
      } 						\
} while (0)


/*
 * cx231xx_i2c_send_bytes()
 */
int cx231xx_i2c_send_bytes(struct i2c_adapter *i2c_adap,
			 const struct i2c_msg *msg)
{
	struct cx231xx_i2c *bus = i2c_adap->algo_data;
	struct cx231xx *dev = bus->dev;
    struct cx231xx_i2c_xfer_data req_data;
    int status = 0;
    u16 size = 0;
    u8 loop = 0;
    u8 saddr_len = 1;
    u8 *buf_ptr = NULL;
    u16 saddr = 0;
    u8 need_gpio = 0;


    if( (bus->nr ==1) && (msg->addr == 0x61) && (dev->tuner_type == TUNER_XC5000) ) {

        size = msg->len;

        if( size == 2 ) { /* register write sub addr*/

            /* Just writing sub address will cause problem to XC5000
               So ignore the request */
            return 0;

        } else if( size == 4 ) { /* register write with sub addr*/

            if(msg->len >= 2 )
                saddr = msg->buf[0] << 8 | msg->buf[1];
            else if ( msg->len == 1 )
                saddr = msg->buf[0];

            switch(saddr) {
                case 0x0000:    /* start tuner calibration mode */
                    need_gpio = 1;
                    dev->xc_fw_load_done = 1; /* FW Loading is done */
                    break;
                case 0x000D:    /* Set signal source */
                case 0x0001:    /* Set TV standard - Video */
                case 0x0002:    /* Set TV standard - Audio */
                case 0x0003:    /* Set RF Frequency */
                    need_gpio = 1;
                    break;
                default:
                    if(dev->xc_fw_load_done)
                        need_gpio = 1;
                    break;
            }

            if(need_gpio ) {
                dprintk1(1, " GPIO W R I T E : addr 0x%x, len %d, saddr 0x%x\n",
                    msg->addr, msg->len,  saddr);

                return dev->cx231xx_gpio_i2c_write(dev, msg->addr, msg->buf, msg->len);
            }

        }

        /* special case for Xc5000 tuner case */
        saddr_len = 1;

        /* adjust the length to correct length */
        size -= saddr_len;
        buf_ptr = (u8*) (msg->buf + 1 );

        do {
            /* prepare xfer_data struct */
            req_data.dev_addr = msg->addr;
            req_data.direction = msg->flags;
            req_data.saddr_len = saddr_len;
            req_data.saddr_dat = msg->buf[0];
            req_data.buf_size =  size > 16 ? 16: size;
            req_data.p_buffer = (u8*)(buf_ptr + loop * 16);

            bus->i2c_nostop =  (size > 16) ? 1: 0;
            bus->i2c_reserve = (loop == 0) ? 0: 1;

            /* usb send command */
            status = dev->cx231xx_send_usb_command(bus, &req_data);
            loop++;

            if( size >= 16 )
                size -=  16;
            else
                size = 0;

        }while( size > 0 );

        bus->i2c_nostop =  0;
        bus->i2c_reserve = 0;

    } else { /* regular case */

        /* prepare xfer_data struct */
        req_data.dev_addr = msg->addr;
        req_data.direction = msg->flags;
        req_data.saddr_len = 0;
        req_data.saddr_dat = 0;
        req_data.buf_size = msg->len;
        req_data.p_buffer = msg->buf;

        /* usb send command */
        status = dev->cx231xx_send_usb_command(bus, &req_data);
    }

    return status < 0 ? status: 0;
}

/*
 * cx231xx_i2c_recv_bytes()
 * read a byte from the i2c device
 */
static int cx231xx_i2c_recv_bytes(struct i2c_adapter *i2c_adap,
			 const struct i2c_msg *msg)
{
    struct cx231xx_i2c *bus = i2c_adap->algo_data;
	struct cx231xx *dev = bus->dev;
    struct cx231xx_i2c_xfer_data req_data;
    int status = 0;
    u16 saddr = 0;
    u8 need_gpio = 0;

    if((bus->nr ==1) && (msg->addr == 0x61) && dev->tuner_type == TUNER_XC5000) {

        if(msg->len == 2 )
            saddr = msg->buf[0] << 8 | msg->buf[1];
        else if ( msg->len == 1 )
            saddr = msg->buf[0];

        if( dev->xc_fw_load_done) {

            switch(saddr) {
                case 0x0009:    /* BUSY check */
                    dprintk1(1, " GPIO R E A D : Special case BUSY check \n");
                    /* Try to read BUSY register, just set it to zero */
                    msg->buf[0] = 0;
                    if(msg->len == 2 )
                        msg->buf[1] = 0;
                    return 0;
                case 0x0004:    /* read Lock status */
                    need_gpio = 1;
                    break;

            }

            if(need_gpio) {
                /* this is a special case to handle Xceive tuner clock stretch issue
                   with gpio based I2C interface */
                dprintk1(1, " GPIO R E A D : addr 0x%x, len %d, saddr 0x%x\n",
                    msg->addr, msg->len, msg->buf[0] << 8| msg->buf[1]);
                status = dev->cx231xx_gpio_i2c_write(dev, msg->addr, msg->buf, msg->len);
                status = dev->cx231xx_gpio_i2c_read(dev, msg->addr, msg->buf, msg->len);
                return status;
            }
        }

         /* prepare xfer_data struct */
        req_data.dev_addr = msg->addr;
        req_data.direction = msg->flags;
        req_data.saddr_len = msg->len;
        req_data.saddr_dat = msg->buf[0] << 8 | msg->buf[1];
        req_data.buf_size = msg->len;
        req_data.p_buffer = msg->buf;

        /* usb send command */
        status = dev->cx231xx_send_usb_command(bus, &req_data);

    } else {

        /* prepare xfer_data struct */
        req_data.dev_addr = msg->addr;
        req_data.direction = msg->flags;
        req_data.saddr_len = 0;
        req_data.saddr_dat = 0;
        req_data.buf_size = msg->len;
        req_data.p_buffer = msg->buf;

        /* usb send command */
        status = dev->cx231xx_send_usb_command(bus, &req_data);
    }

    return status < 0 ? status: 0;
}

/*
 * cx231xx_i2c_recv_bytes_with_saddr()
 * read a byte from the i2c device
 */
static int cx231xx_i2c_recv_bytes_with_saddr(struct i2c_adapter *i2c_adap,
			 const struct i2c_msg *msg1, const struct i2c_msg *msg2)
{
    struct cx231xx_i2c *bus = i2c_adap->algo_data;
	struct cx231xx *dev = bus->dev;
    struct cx231xx_i2c_xfer_data req_data;
    int status = 0;
    u16 saddr = 0;
    u8 need_gpio = 0;

    if(msg1->len == 2 )
        saddr = msg1->buf[0] << 8 | msg1->buf[1];
    else if ( msg1->len == 1 )
        saddr = msg1->buf[0];

    if ( (bus->nr ==1) && (msg2->addr == 0x61) &&  dev->tuner_type == TUNER_XC5000) {

        if( (msg2->len < 16) ) {

            dprintk1(1, " i2c_read : addr 0x%x, len %d, subaddr 0x%x, leng %d\n",
                msg2->addr, msg2->len, saddr, msg1->len);

            switch(saddr) {
                case 0x0008:    /* read FW load status */
                    need_gpio = 1;
                    break;
                case 0x0004:    /* read Lock status */
                    need_gpio = 1;
                    break;
            }

            if(need_gpio ) {
                status = dev->cx231xx_gpio_i2c_write(dev, msg1->addr, msg1->buf, msg1->len);
                status = dev->cx231xx_gpio_i2c_read(dev, msg2->addr, msg2->buf, msg2->len);
                return status;
            }
        }
    }

    /* prepare xfer_data struct */
    req_data.dev_addr = msg2->addr;
    req_data.direction = msg2->flags;
    req_data.saddr_len = msg1->len;
    req_data.saddr_dat = saddr;
    req_data.buf_size = msg2->len;
    req_data.p_buffer = msg2->buf;

    /* usb send command */
    status = dev->cx231xx_send_usb_command(bus, &req_data);

    return status < 0 ? status: 0;
}

/*
 * cx231xx_i2c_check_for_device()
 * check if there is a i2c_device at the supplied address
 */
static int cx231xx_i2c_check_for_device(struct i2c_adapter *i2c_adap,
			 const struct i2c_msg *msg)
{
    struct cx231xx_i2c *bus = i2c_adap->algo_data;
	struct cx231xx *dev = bus->dev;
    struct cx231xx_i2c_xfer_data req_data;
    int status = 0;

    /* prepare xfer_data struct */
    req_data.dev_addr = msg->addr;
    req_data.direction = msg->flags;
    req_data.saddr_len = 0;
    req_data.saddr_dat = 0;
    req_data.buf_size = 0;
    req_data.p_buffer = NULL;

    /* usb send command */
    status = dev->cx231xx_send_usb_command(bus, &req_data);

    return status < 0 ? status: 0;
}

/*
 * cx231xx_i2c_xfer()
 * the main i2c transfer function
 */
static int cx231xx_i2c_xfer(struct i2c_adapter *i2c_adap,
			   struct i2c_msg msgs[], int num)
{
	struct cx231xx_i2c *bus = i2c_adap->algo_data;
	struct cx231xx *dev = bus->dev;
	int addr, rc, i, byte;

	if (num <= 0)
		return 0;

	for (i = 0; i < num; i++) {

		addr = msgs[i].addr >> 1;

		dprintk2(2, "%s %s addr=%x len=%d:",
			 (msgs[i].flags & I2C_M_RD) ? "read" : "write",
			 i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
		if (!msgs[i].len) { /* no len: check only for device presence */
			rc = cx231xx_i2c_check_for_device(i2c_adap, &msgs[i]);
			if (rc < 0) {
				dprintk2(2, " no device\n");
				return rc;
			}

		} else if (msgs[i].flags & I2C_M_RD) {
			/* read bytes */
			rc = cx231xx_i2c_recv_bytes(i2c_adap, &msgs[i]);
			if (i2c_debug >= 2) {
				for (byte = 0; byte < msgs[i].len; byte++)
					printk(" %02x", msgs[i].buf[byte]);
			}
		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
			   msgs[i].addr == msgs[i + 1].addr  && (msgs[i].len <= 2) && (bus->nr < 2)) {
			/* read bytes */
			rc = cx231xx_i2c_recv_bytes_with_saddr(i2c_adap, &msgs[i], &msgs[i+1]);
			if (i2c_debug >= 2) {
				for (byte = 0; byte < msgs[i].len; byte++)
					printk(" %02x", msgs[i].buf[byte]);
			}
            i++;
		} else {
			/* write bytes */
			if (i2c_debug >= 2) {
				for (byte = 0; byte < msgs[i].len; byte++)
					printk(" %02x", msgs[i].buf[byte]);
			}
			rc = cx231xx_i2c_send_bytes(i2c_adap,&msgs[i]);
		}
		if (rc < 0)
			goto err;
		if (i2c_debug >= 2)
			printk("\n");
	}

	return num;
err:
	dprintk2(2, " ERROR: %i\n", rc);
	return rc;
}

/* ----------------------------------------------------------- */

/*
 * functionality()
 */
static u32 functionality(struct i2c_adapter *adap)
{
	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
}

/*
 * attach_inform()
 * gets called when a device attaches to the i2c bus
 * does some basic configuration
 */
static int attach_inform(struct i2c_client *client)
{
    struct cx231xx_i2c *bus = i2c_get_adapdata(client->adapter);
	struct cx231xx *dev = bus->dev;

	switch (client->addr << 1) {
	case 0x32:
		dprintk1(1, "attach_inform: Geminit III detected.\n");
		break;
	case 0x02:
		dprintk1(1, "attach_inform: Acquarius detected.\n");
		break;
	case 0xa0:
		dprintk1(1, "attach_inform: eeprom detected.\n");
		break;
	case 0x60:
        dprintk1(1, "attach_inform: Colibri detected.\n");
        break;
	case 0x8e:
	{
		struct IR_i2c *ir = i2c_get_clientdata(client);
		dprintk1(1, "attach_inform: IR detected (%s).\n",
			ir->phys);
		cx231xx_set_ir(dev, ir);
		break;
	}
	case 0x80:
	case 0x88:
		dprintk1(1, "attach_inform: Hammerhead detected.\n");
		break;

	default:
		if (!dev->tuner_addr)
			dev->tuner_addr = client->addr;

		dprintk1(1, "attach inform: detected I2C address %x\n",
				client->addr << 1);
	}

	return 0;
}

static int detach_inform(struct i2c_client *client)
{
	dprintk1(1, "i2c detach [client=%s]\n", client->name);
	return 0;
}


static struct i2c_algorithm cx231xx_algo = {
	.master_xfer   = cx231xx_i2c_xfer,
	.functionality = functionality,
};

static struct i2c_adapter cx231xx_adap_template = {
	.owner = THIS_MODULE,
	.class = I2C_CLASS_TV_ANALOG,
	.name = "cx231xx",
	.id = I2C_HW_B_CX231XX,
	.algo = &cx231xx_algo,
	.client_register   = attach_inform,
	.client_unregister = detach_inform,
};

static struct i2c_client cx231xx_client_template = {
	.name = "cx231xx internal",
};

/* ----------------------------------------------------------- */

/*
 * i2c_devs
 * incomplete list of known devices
 */
static char *i2c_devs[128] = {
	[0x60 >> 1] = "colibri",
	[0x88 >> 1] = "hammerhead",
    [0x8e >> 1] = "CIR",
	[0x32 >> 1] = "GeminiIII",
    [0x02 >> 1] = "Aquarius",
	[0xa0 >> 1] = "eeprom",
	[0xc0 >> 1] = "tuner/XC3028",
	[0xc2 >> 1] = "tuner/XC5000",
};

/*
 * cx231xx_do_i2c_scan()
 * check i2c address range for devices
 */
void cx231xx_do_i2c_scan(struct cx231xx *dev, struct i2c_client *c)
{
	unsigned char buf;
	int i, rc;

    cx231xx_info(": Checking for I2C devices ..\n");
	for (i = 0; i < 128; i++) {
		c->addr = i;
		rc = i2c_master_recv(c, &buf, 0);
		if (rc < 0)
			continue;
		cx231xx_info("%s: i2c scan: found device @ 0x%x  [%s]\n",
		       dev->name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
	}
    cx231xx_info(": Completed Checking for I2C devices.\n");
}

/*
 * cx231xx_i2c_call_clients()
 * send commands to all attached i2c devices
 */
void cx231xx_i2c_call_clients(struct cx231xx_i2c *bus, unsigned int cmd, void *arg)
{
	/* struct cx231xx *dev = bus->dev; */

	BUG_ON(NULL == bus->i2c_adap.algo_data);
	i2c_clients_command(&bus->i2c_adap, cmd, arg);
}

/*
 * cx231xx_i2c_register()
 * register i2c bus
 */
int cx231xx_i2c_register(struct cx231xx_i2c *bus)
{
    struct cx231xx *dev = bus->dev;

    BUG_ON(!dev->cx231xx_send_usb_command);

    cx231xx_info("%s(bus = %d)\n", __func__, bus->nr);

	memcpy(&bus->i2c_adap, &cx231xx_adap_template,
	       sizeof(bus->i2c_adap));
	memcpy(&bus->i2c_algo, &cx231xx_algo,
	       sizeof(bus->i2c_algo));
	memcpy(&bus->i2c_client, &cx231xx_client_template,
	       sizeof(bus->i2c_client));

	bus->i2c_adap.dev.parent = &dev->udev->dev;

	strlcpy(bus->i2c_adap.name, bus->dev->name,
		sizeof(bus->i2c_adap.name));

	bus->i2c_algo.data = bus;
	bus->i2c_adap.algo_data = bus;
	i2c_set_adapdata(&bus->i2c_adap, bus);
	i2c_add_adapter(&bus->i2c_adap);

	bus->i2c_client.adapter = &bus->i2c_adap;

	if (0 == bus->i2c_rc) {
		cx231xx_info("%s: i2c bus %d registered\n", dev->name, bus->nr);
		if (i2c_scan)
			cx231xx_do_i2c_scan(dev, &bus->i2c_client);
	} else
		cx231xx_warn("%s: i2c bus %d register FAILED\n",
			dev->name, bus->nr);

	return bus->i2c_rc;
}

/*
 * cx231xx_i2c_unregister()
 * unregister i2c_bus
 */
int cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
{
	i2c_del_adapter(&bus->i2c_adap);
	return 0;
}