V4L/DVB (4662): Pvrusb2: Implement VIDIOC_INT_[G|S]_REGISTER

Implement VIDIOC_INT_SET_REGISTER and VIDIOC_INT_GET_REGISTER for the
pvrusb2 driver.  This is a debugging aid which will not be enabled
unless CONFIG_VIDEO_ADV_DEBUG has been enabled.
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/pvrusb2/pvrusb2-hdw.c

@@ -24,6 +24,7 @@
 #include <linux/slab.h>
 #include <linux/firmware.h>
 #include <linux/videodev2.h>
+#include <media/v4l2-common.h>
 #include <asm/semaphore.h>
 #include "pvrusb2.h"
 #include "pvrusb2-std.h"
@@ -3131,6 +3132,37 @@ static int pvr2_hdw_get_eeprom_addr(struct pvr2_hdw *hdw)
 }
 
 
+int pvr2_hdw_register_access(struct pvr2_hdw *hdw,
+			     u32 chip_id,unsigned long reg_id,
+			     int setFl,u32 *val_ptr)
+{
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	struct list_head *item;
+	struct pvr2_i2c_client *cp;
+	struct v4l2_register req;
+	int stat;
+
+	req.i2c_id = chip_id;
+	req.reg = reg_id;
+	if (setFl) req.val = *val_ptr;
+	mutex_lock(&hdw->i2c_list_lock); do {
+		list_for_each(item,&hdw->i2c_clients) {
+			cp = list_entry(item,struct pvr2_i2c_client,list);
+			if (cp->client->driver->id != chip_id) continue;
+			stat = pvr2_i2c_client_cmd(
+				cp,(setFl ? VIDIOC_INT_S_REGISTER :
+				    VIDIOC_INT_G_REGISTER),&req);
+			if (!setFl) *val_ptr = req.val;
+			return stat;
+		}
+	} while (0); mutex_unlock(&hdw->i2c_list_lock);
+	return -EINVAL;
+#else
+	return -ENOSYS;
+#endif
+}
+
+
 /*
   Stuff for Emacs to see, in order to encourage consistent editing style:
   *** Local Variables: ***

drivers/media/video/pvrusb2/pvrusb2-hdw.h

@@ -211,6 +211,14 @@ int pvr2_hdw_v4l_get_minor_number(struct pvr2_hdw *);
 /* Store the v4l minor device number */
 void pvr2_hdw_v4l_store_minor_number(struct pvr2_hdw *,int);
 
+/* Direct read/write access to chip's registers:
+   chip_id - unique id of chip (e.g. I2C_DRIVERD_xxxx)
+   reg_id  - register number to access
+   setFl   - true to set the register, false to read it
+   val_ptr - storage location for source / result. */
+int pvr2_hdw_register_access(struct pvr2_hdw *,
+			     u32 chip_id,unsigned long reg_id,
+			     int setFl,u32 *val_ptr);
 
 /* The following entry points are all lower level things you normally don't
    want to worry about. */

drivers/media/video/pvrusb2/pvrusb2-v4l2.c

@@ -671,6 +671,20 @@ static int pvr2_v4l2_do_ioctl(struct inode *inode, struct file *file,
 		ret = 0;
 		break;
 	}
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	case VIDIOC_INT_G_REGISTER:
+	case VIDIOC_INT_S_REGISTER:
+	{
+		u32 val;
+		struct v4l2_register *req = (struct v4l2_register *)arg;
+		if (cmd == VIDIOC_INT_S_REGISTER) val = req->val;
+		ret = pvr2_hdw_register_access(
+			hdw,req->i2c_id,req->reg,
+			cmd == VIDIOC_INT_S_REGISTER,&val);
+		if (cmd == 0) req->val = val;
+		break;
+	}
+#endif
 
 	default :
 		ret = v4l_compat_translate_ioctl(inode,file,cmd,