V4L/DVB (4922): Add usbvision driver

This patch adds usbvision into V4L/DVB HG tree.
Usbvision driver is a GPL driver, made by:
	Joerg Heckenbach <joerg@heckenbach-aw.de>
		and
	Dwaine Garden <DwaineGarden@rogers.com>
V4L2 migration made by:
	Thierry Merle <thierry.merle@free.fr>
Kconfig/Makefile scripts by:
	Mauro Carvalho Chehab <mchehab@infradead.org>

Signed-off-by: Joerg Heckenbach <joerg@heckenbach-aw.de>
Signed-off-by: Dwaine Garden <dwainegarden@rogers.com>
Signed-off-by: Thierry Merle <thierry.merle@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 265 insertions, 0 deletions

diff --git a/drivers/media/video/usbvision/usbvision-i2c.c b/drivers/media/video/usbvision/usbvision-i2c.c
new file mode 100644
index 000000000000..e050e5559ac5
--- /dev/null
+++ b/drivers/media/video/usbvision/usbvision-i2c.c
@@ -0,0 +1,265 @@
+/* 
+ * I2C_ALGO_USB.C
+ *  i2c algorithm for USB-I2C Bridges
+ *
+ * Copyright (c) 1999-2005 Joerg Heckenbach <joerg@heckenbach-aw.de>
+ *                         Dwaine Garden <dwainegarden@rogers.com>
+ *
+ * This module is part of usbvision driver project.
+ * Updates to driver completed by Dwaine P. Garden
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/version.h>
+        #include <linux/utsname.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/usb.h>
+#include <linux/i2c.h>
+#include "usbvision-i2c.h"
+
+static int debug = 0;   
+
+#if defined(module_param)                               // Showing parameters under SYSFS
+module_param (debug, int, 0444);                        // debug mode of the device driver
+#else
+MODULE_PARM(debug, "i");                                // debug mode of the device driver
+#endif
+
+MODULE_AUTHOR("Joerg Heckenbach");
+MODULE_DESCRIPTION("I2C algorithm for USB-I2C-bridges");
+MODULE_LICENSE("GPL");
+
+
+static inline int try_write_address(struct i2c_adapter *i2c_adap,
+                                    unsigned char addr, int retries)
+{
+        struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
+        void *data;
+        int i, ret = -1;
+        char buf[4];
+
+        data = i2c_get_adapdata(i2c_adap);
+        buf[0] = 0x00;
+        for (i = 0; i <= retries; i++) {
+                ret = (adap->outb(data, addr, buf, 1));
+                if (ret == 1)
+                        break;  /* success! */
+                udelay(5 /*adap->udelay */ );
+                if (i == retries)       /* no success */
+                        break;
+                udelay(adap->udelay);
+        }
+        if (debug) {
+                if (i) {
+                        info("%s: Needed %d retries for address %#2x", __FUNCTION__, i, addr);
+                        info("%s: Maybe there's no device at this address", __FUNCTION__);
+                }
+        }
+        return ret;
+}
+
+static inline int try_read_address(struct i2c_adapter *i2c_adap,
+                                   unsigned char addr, int retries)
+{
+        struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
+        void *data;
+        int i, ret = -1;
+        char buf[4];
+
+        data = i2c_get_adapdata(i2c_adap);
+        for (i = 0; i <= retries; i++) {
+                ret = (adap->inb(data, addr, buf, 1));
+                if (ret == 1)
+                        break;  /* success! */
+                udelay(5 /*adap->udelay */ );
+                if (i == retries)       /* no success */
+                        break;
+                udelay(adap->udelay);
+        }
+        if (debug) {
+                if (i) {
+                        info("%s: Needed %d retries for address %#2x", __FUNCTION__, i, addr);
+                        info("%s: Maybe there's no device at this address", __FUNCTION__);
+                }
+        }
+        return ret;
+}
+
+static inline int usb_find_address(struct i2c_adapter *i2c_adap,
+                                   struct i2c_msg *msg, int retries,
+                                   unsigned char *add)
+{
+        unsigned short flags = msg->flags;
+        
+        unsigned char addr;
+        int ret;
+        if ((flags & I2C_M_TEN)) {
+                /* a ten bit address */
+                addr = 0xf0 | ((msg->addr >> 7) & 0x03);
+                /* try extended address code... */
+                ret = try_write_address(i2c_adap, addr, retries);
+                if (ret != 1) {
+                        err("died at extended address code, while writing");
+                        return -EREMOTEIO;
+                }
+                add[0] = addr;
+                if (flags & I2C_M_RD) {
+                        /* okay, now switch into reading mode */
+                        addr |= 0x01;
+                        ret = try_read_address(i2c_adap, addr, retries);
+                        if (ret != 1) {
+                                err("died at extended address code, while reading");
+                                return -EREMOTEIO;
+                        }
+                }
+
+        } else {                /* normal 7bit address  */
+                addr = (msg->addr << 1);
+                if (flags & I2C_M_RD)
+                        addr |= 1;
+                if (flags & I2C_M_REV_DIR_ADDR)
+                        addr ^= 1;
+
+                add[0] = addr;
+                if (flags & I2C_M_RD)
+                        ret = try_read_address(i2c_adap, addr, retries);
+                else
+                        ret = try_write_address(i2c_adap, addr, retries);
+
+                if (ret != 1) {
+                        return -EREMOTEIO;
+                }
+        }
+        return 0;
+}
+
+static int
+usb_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
+{
+        struct i2c_msg *pmsg;
+        struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
+        void *data;
+        int i, ret;
+        unsigned char addr;
+
+        data = i2c_get_adapdata(i2c_adap);
+
+        for (i = 0; i < num; i++) {
+                pmsg = &msgs[i];
+                ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
+                if (ret != 0) {
+                        if (debug) {
+                                info("%s: got NAK from device, message #%d\n", __FUNCTION__, i);
+                        }
+                        return (ret < 0) ? ret : -EREMOTEIO;
+                }
+
+                if (pmsg->flags & I2C_M_RD) {
+                        /* read bytes into buffer */
+                        ret = (adap->inb(data, addr, pmsg->buf, pmsg->len));
+                        if (ret < pmsg->len) {
+                                return (ret < 0) ? ret : -EREMOTEIO;
+                        }
+                } else {
+                        /* write bytes from buffer */
+                        ret = (adap->outb(data, addr, pmsg->buf, pmsg->len));
+                        if (ret < pmsg->len) {
+                                return (ret < 0) ? ret : -EREMOTEIO;
+                        }
+                }
+        }
+        return num;
+}
+
+static int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
+{
+        return 0;
+}
+
+static u32 usb_func(struct i2c_adapter *adap)
+{
+        return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
+}
+
+
+/* -----exported algorithm data: -------------------------------------  */
+
+static struct i2c_algorithm i2c_usb_algo = {
+        .master_xfer   = usb_xfer,
+        .smbus_xfer    = NULL,
+        .slave_send    = NULL,
+        .slave_recv    = NULL,
+        .algo_control  = algo_control,
+        .functionality = usb_func,
+};
+
+
+/*
+ * registering functions to load algorithms at runtime
+ */
+int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
+{
+        /* register new adapter to i2c module... */
+
+        adap->algo = &i2c_usb_algo;
+
+        adap->timeout = 100;    /* default values, should       */
+        adap->retries = 3;      /* be replaced by defines       */
+
+#ifdef MODULE
+        #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 4, 21)
+                MOD_INC_USE_COUNT;
+        #endif
+#endif
+
+        i2c_add_adapter(adap);
+
+        if (debug) {
+                info("i2c bus for %s registered", adap->name);
+        }
+
+        return 0;
+}
+
+
+int usbvision_i2c_usb_del_bus(struct i2c_adapter *adap)
+{
+
+        i2c_del_adapter(adap);
+
+        if (debug) {
+                info("i2c bus for %s unregistered", adap->name);
+        }
+#ifdef MODULE
+        #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 4, 21)
+                MOD_DEC_USE_COUNT;
+        #endif
+#endif
+
+        return 0;
+}
+
+EXPORT_SYMBOL(usbvision_i2c_usb_add_bus);
+EXPORT_SYMBOL(usbvision_i2c_usb_del_bus);