File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/media/usb/usbvision/usbvision-i2c.c b/drivers/media/usb/usbvision/usbvision-i2c.c
new file mode 100644
index 0000000..120de2e
--- /dev/null
+++ b/drivers/media/usb/usbvision/usbvision-i2c.c
@@ -0,0 +1,447 @@
+/*
+ * usbvision_i2c.c
+ *  i2c algorithm for USB-I2C Bridges
+ *
+ * Copyright (c) 1999-2007 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/init.h>
+#include <linux/uaccess.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/usb.h>
+#include <linux/i2c.h>
+#include "usbvision.h"
+
+#define DBG_I2C		(1 << 0)
+
+static int i2c_debug;
+
+module_param(i2c_debug, int, 0644);			/* debug_i2c_usb mode of the device driver */
+MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
+
+#define PDEBUG(level, fmt, args...) { \
+		if (i2c_debug & (level)) \
+			printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \
+				__func__, __LINE__ , ## args); \
+	}
+
+static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
+			    short len);
+static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
+			   short len);
+
+static inline int try_write_address(struct i2c_adapter *i2c_adap,
+				    unsigned char addr, int retries)
+{
+	struct usb_usbvision *usbvision;
+	int i, ret = -1;
+	char buf[4];
+
+	usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
+	buf[0] = 0x00;
+	for (i = 0; i <= retries; i++) {
+		ret = (usbvision_i2c_write(usbvision, addr, buf, 1));
+		if (ret == 1)
+			break;	/* success! */
+		udelay(5);
+		if (i == retries)	/* no success */
+			break;
+		udelay(10);
+	}
+	if (i) {
+		PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
+		PDEBUG(DBG_I2C, "Maybe there's no device at this address");
+	}
+	return ret;
+}
+
+static inline int try_read_address(struct i2c_adapter *i2c_adap,
+				   unsigned char addr, int retries)
+{
+	struct usb_usbvision *usbvision;
+	int i, ret = -1;
+	char buf[4];
+
+	usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
+	for (i = 0; i <= retries; i++) {
+		ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
+		if (ret == 1)
+			break;	/* success! */
+		udelay(5);
+		if (i == retries)	/* no success */
+			break;
+		udelay(10);
+	}
+	if (i) {
+		PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
+		PDEBUG(DBG_I2C, "Maybe there's no device at this address");
+	}
+	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;
+
+	addr = (msg->addr << 1);
+	if (flags & I2C_M_RD)
+		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
+usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
+{
+	struct i2c_msg *pmsg;
+	struct usb_usbvision *usbvision;
+	int i, ret;
+	unsigned char addr = 0;
+
+	usbvision = (struct usb_usbvision *)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) {
+			PDEBUG(DBG_I2C, "got NAK from device, message #%d", i);
+			return (ret < 0) ? ret : -EREMOTEIO;
+		}
+
+		if (pmsg->flags & I2C_M_RD) {
+			/* read bytes into buffer */
+			ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
+			if (ret < pmsg->len)
+				return (ret < 0) ? ret : -EREMOTEIO;
+		} else {
+			/* write bytes from buffer */
+			ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
+			if (ret < pmsg->len)
+				return (ret < 0) ? ret : -EREMOTEIO;
+		}
+	}
+	return num;
+}
+
+static u32 functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+/* -----exported algorithm data: -------------------------------------	*/
+
+static struct i2c_algorithm usbvision_algo = {
+	.master_xfer   = usbvision_i2c_xfer,
+	.smbus_xfer    = NULL,
+	.functionality = functionality,
+};
+
+
+/* ----------------------------------------------------------------------- */
+/* usbvision specific I2C functions                                        */
+/* ----------------------------------------------------------------------- */
+static struct i2c_adapter i2c_adap_template;
+
+int usbvision_i2c_register(struct usb_usbvision *usbvision)
+{
+	static unsigned short saa711x_addrs[] = {
+		0x4a >> 1, 0x48 >> 1,	/* SAA7111, SAA7111A and SAA7113 */
+		0x42 >> 1, 0x40 >> 1,	/* SAA7114, SAA7115 and SAA7118 */
+		I2C_CLIENT_END };
+
+	if (usbvision->registered_i2c)
+		return 0;
+
+	usbvision->i2c_adap = i2c_adap_template;
+
+	sprintf(usbvision->i2c_adap.name, "%s-%d-%s", i2c_adap_template.name,
+		usbvision->dev->bus->busnum, usbvision->dev->devpath);
+	PDEBUG(DBG_I2C, "Adaptername: %s", usbvision->i2c_adap.name);
+	usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
+
+	i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev);
+
+	if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
+		printk(KERN_ERR "usbvision_i2c_register: can't write reg\n");
+		return -EBUSY;
+	}
+
+	PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
+	PDEBUG(DBG_I2C, "ALGO   debugging is enabled [i2c]");
+
+	/* register new adapter to i2c module... */
+
+	usbvision->i2c_adap.algo = &usbvision_algo;
+
+	usbvision->i2c_adap.timeout = 100;	/* default values, should       */
+	usbvision->i2c_adap.retries = 3;	/* be replaced by defines       */
+
+	i2c_add_adapter(&usbvision->i2c_adap);
+
+	PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name);
+
+	/* Request the load of the i2c modules we need */
+	switch (usbvision_device_data[usbvision->dev_model].codec) {
+	case CODEC_SAA7113:
+	case CODEC_SAA7111:
+		/* Without this delay the detection of the saa711x is
+		   hit-and-miss. */
+		mdelay(10);
+		v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
+				&usbvision->i2c_adap,
+				"saa7115_auto", 0, saa711x_addrs);
+		break;
+	}
+	if (usbvision_device_data[usbvision->dev_model].tuner == 1) {
+		struct v4l2_subdev *sd;
+		enum v4l2_i2c_tuner_type type;
+		struct tuner_setup tun_setup;
+
+		sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
+				&usbvision->i2c_adap,
+				"tuner", 0, v4l2_i2c_tuner_addrs(ADDRS_DEMOD));
+		/* depending on whether we found a demod or not, select
+		   the tuner type. */
+		type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV;
+
+		sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
+				&usbvision->i2c_adap,
+				"tuner", 0, v4l2_i2c_tuner_addrs(type));
+
+		if (sd == NULL)
+			return -ENODEV;
+		if (usbvision->tuner_type != -1) {
+			tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
+			tun_setup.type = usbvision->tuner_type;
+			tun_setup.addr = v4l2_i2c_subdev_addr(sd);
+			call_all(usbvision, tuner, s_type_addr, &tun_setup);
+		}
+	}
+	usbvision->registered_i2c = 1;
+
+	return 0;
+}
+
+int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
+{
+	if (!usbvision->registered_i2c)
+		return 0;
+
+	i2c_del_adapter(&(usbvision->i2c_adap));
+	usbvision->registered_i2c = 0;
+
+	PDEBUG(DBG_I2C, "i2c bus for %s unregistered", usbvision->i2c_adap.name);
+
+	return 0;
+}
+
+static int
+usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
+		     char *buf, short len)
+{
+	int rc, retries;
+
+	for (retries = 5;;) {
+		rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
+		if (rc < 0)
+			return rc;
+
+		/* Initiate byte read cycle                    */
+		/* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
+		/*                    d3 0=Wr 1=Rd             */
+		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
+				      (len & 0x07) | 0x18);
+		if (rc < 0)
+			return rc;
+
+		/* Test for Busy and ACK */
+		do {
+			/* USBVISION_SER_CONT -> d4 == 0 busy */
+			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
+		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
+		if (rc < 0)
+			return rc;
+
+		/* USBVISION_SER_CONT -> d5 == 1 Not ack */
+		if ((rc & 0x20) == 0)	/* Ack? */
+			break;
+
+		/* I2C abort */
+		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
+		if (rc < 0)
+			return rc;
+
+		if (--retries < 0)
+			return -1;
+	}
+
+	switch (len) {
+	case 4:
+		buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
+	case 3:
+		buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
+	case 2:
+		buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
+	case 1:
+		buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
+		break;
+	default:
+		printk(KERN_ERR
+		       "usbvision_i2c_read_max4: buffer length > 4\n");
+	}
+
+	if (i2c_debug & DBG_I2C) {
+		int idx;
+
+		for (idx = 0; idx < len; idx++)
+			PDEBUG(DBG_I2C, "read %x from address %x", (unsigned char)buf[idx], addr);
+	}
+	return len;
+}
+
+
+static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
+				 unsigned char addr, const char *buf,
+				 short len)
+{
+	int rc, retries;
+	int i;
+	unsigned char *value = usbvision->ctrl_urb_buffer;
+	unsigned char ser_cont;
+
+	ser_cont = (len & 0x07) | 0x10;
+
+	value[0] = addr;
+	value[1] = ser_cont;
+	for (i = 0; i < len; i++)
+		value[i + 2] = buf[i];
+
+	for (retries = 5;;) {
+		rc = usb_control_msg(usbvision->dev,
+				     usb_sndctrlpipe(usbvision->dev, 1),
+				     USBVISION_OP_CODE,
+				     USB_DIR_OUT | USB_TYPE_VENDOR |
+				     USB_RECIP_ENDPOINT, 0,
+				     (__u16) USBVISION_SER_ADRS, value,
+				     len + 2, HZ);
+
+		if (rc < 0)
+			return rc;
+
+		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
+				      (len & 0x07) | 0x10);
+		if (rc < 0)
+			return rc;
+
+		/* Test for Busy and ACK */
+		do {
+			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
+		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
+		if (rc < 0)
+			return rc;
+
+		if ((rc & 0x20) == 0)	/* Ack? */
+			break;
+
+		/* I2C abort */
+		usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
+
+		if (--retries < 0)
+			return -1;
+
+	}
+
+	if (i2c_debug & DBG_I2C) {
+		int idx;
+
+		for (idx = 0; idx < len; idx++)
+			PDEBUG(DBG_I2C, "wrote %x at address %x", (unsigned char)buf[idx], addr);
+	}
+	return len;
+}
+
+static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
+			    short len)
+{
+	char *buf_ptr = buf;
+	int retval;
+	int wrcount = 0;
+	int count;
+	int max_len = 4;
+
+	while (len > 0) {
+		count = (len > max_len) ? max_len : len;
+		retval = usbvision_i2c_write_max4(usbvision, addr, buf_ptr, count);
+		if (retval > 0) {
+			len -= count;
+			buf_ptr += count;
+			wrcount += count;
+		} else
+			return (retval < 0) ? retval : -EFAULT;
+	}
+	return wrcount;
+}
+
+static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
+			   short len)
+{
+	char temp[4];
+	int retval, i;
+	int rdcount = 0;
+	int count;
+
+	while (len > 0) {
+		count = (len > 3) ? 4 : len;
+		retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
+		if (retval > 0) {
+			for (i = 0; i < len; i++)
+				buf[rdcount + i] = temp[i];
+			len -= count;
+			rdcount += count;
+		} else
+			return (retval < 0) ? retval : -EFAULT;
+	}
+	return rdcount;
+}
+
+static struct i2c_adapter i2c_adap_template = {
+	.owner = THIS_MODULE,
+	.name              = "usbvision",
+};