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authorMauro Carvalho Chehab <mchehab@infradead.org>2006-12-04 14:30:53 +0300
committerMauro Carvalho Chehab <mchehab@infradead.org>2006-12-10 14:05:39 +0300
commit781aa1d1ab7ba13314af0af6c5d70c0eb0e96bf4 (patch)
tree5342519b3c90b710dbb9f8fca2240147344b70fc /drivers/media/video/usbvision/usbvision-i2c.c
parent2a893dea0f186efc2eb4bcdaee145b20c87d239d (diff)
downloadlinux-781aa1d1ab7ba13314af0af6c5d70c0eb0e96bf4.tar.xz
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>
Diffstat (limited to 'drivers/media/video/usbvision/usbvision-i2c.c')
-rw-r--r--drivers/media/video/usbvision/usbvision-i2c.c265
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);