V4L/DVB (5304): Improve chip matching in v4l2_register

The chip matching in struct v4l2_register for VIDIOC_DBG_G/S_REGISTER 
was rather primitive. It could not be extended to other busses besides 
i2c and it lacked a way to.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/cx25840/cx25840-core.c

@@ -633,7 +633,7 @@ static int cx25840_command(struct i2c_client *client, unsigned int cmd,
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_CX25840)
+		if (!v4l2_chip_match_i2c_client(client, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;

drivers/media/video/cx88/cx88-video.c

@@ -1389,7 +1389,7 @@ static int vidioc_g_register (struct file *file, void *fh,
 {
 	struct cx88_core *core = ((struct cx8800_fh*)fh)->dev->core;
 
-	if (reg->i2c_id != 0)
+	if (!v4l2_chip_match_host(reg->match_type, reg->match_chip))
 		return -EINVAL;
 	/* cx2388x has a 24-bit register space */
 	reg->val = cx_read(reg->reg&0xffffff);
@@ -1401,7 +1401,7 @@ static int vidioc_s_register (struct file *file, void *fh,
 {
 	struct cx88_core *core = ((struct cx8800_fh*)fh)->dev->core;
 
-	if (reg->i2c_id != 0)
+	if (!v4l2_chip_match_host(reg->match_type, reg->match_chip))
 		return -EINVAL;
 	cx_write(reg->reg&0xffffff, reg->val);
 	return 0;

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

@@ -3256,8 +3256,8 @@ static int pvr2_hdw_get_eeprom_addr(struct pvr2_hdw *hdw)
 
 
 int pvr2_hdw_register_access(struct pvr2_hdw *hdw,
-			     u32 chip_id, u64 reg_id,
-			     int setFl,u32 *val_ptr)
+			     u32 match_type, u32 match_chip, u64 reg_id,
+			     int setFl,u64 *val_ptr)
 {
 #ifdef CONFIG_VIDEO_ADV_DEBUG
 	struct list_head *item;
@@ -3268,13 +3268,16 @@ int pvr2_hdw_register_access(struct pvr2_hdw *hdw,
 
 	if (!capable(CAP_SYS_ADMIN)) return -EPERM;
 
-	req.i2c_id = chip_id;
+	req.match_type = match_type;
+	req.match_chip = match_chip;
 	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;
+			if (!v4l2_chip_match_i2c_client(cp->client, req.match_type, req.match_chip)) {
+				continue;
+			}
 			stat = pvr2_i2c_client_cmd(
 				cp,(setFl ? VIDIOC_DBG_S_REGISTER :
 				    VIDIOC_DBG_G_REGISTER),&req);

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

@@ -217,13 +217,14 @@ void pvr2_hdw_v4l_store_minor_number(struct pvr2_hdw *,
 				     enum pvr2_v4l_type index,int);
 
 /* Direct read/write access to chip's registers:
-   chip_id - unique id of chip (e.g. I2C_DRIVERD_xxxx)
+   match_type - how to interpret match_chip (e.g. driver ID, i2c address)
+   match_chip - chip match value (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,u64 reg_id,
-			     int setFl,u32 *val_ptr);
+			     u32 match_type, u32 match_chip,u64 reg_id,
+			     int setFl,u64 *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

@@ -740,11 +740,11 @@ static int pvr2_v4l2_do_ioctl(struct inode *inode, struct file *file,
 	case VIDIOC_DBG_S_REGISTER:
 	case VIDIOC_DBG_G_REGISTER:
 	{
-		u32 val;
+		u64 val;
 		struct v4l2_register *req = (struct v4l2_register *)arg;
 		if (cmd == VIDIOC_DBG_S_REGISTER) val = req->val;
 		ret = pvr2_hdw_register_access(
-			hdw,req->i2c_id,req->reg,
+			hdw,req->match_type,req->match_chip,req->reg,
 			cmd == VIDIOC_DBG_S_REGISTER,&val);
 		if (cmd == VIDIOC_DBG_G_REGISTER) req->val = val;
 		break;

drivers/media/video/saa7115.c

@@ -1425,7 +1425,7 @@ static int saa711x_command(struct i2c_client *client, unsigned int cmd, void *ar
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_SAA711X)
+		if (!v4l2_chip_match_i2c_client(client, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;

drivers/media/video/saa7127.c

@@ -619,7 +619,7 @@ static int saa7127_command(struct i2c_client *client,
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_SAA7127)
+		if (!v4l2_chip_match_i2c_client(client, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;

drivers/media/video/tvp5150.c

@@ -955,7 +955,7 @@ static int tvp5150_command(struct i2c_client *c,
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_TVP5150)
+		if (!v4l2_chip_match_i2c_client(c, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;

drivers/media/video/upd64031a.c

@@ -167,7 +167,7 @@ static int upd64031a_command(struct i2c_client *client, unsigned int cmd, void *
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_UPD64031A)
+		if (!v4l2_chip_match_i2c_client(client, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;

drivers/media/video/upd64083.c

@@ -144,7 +144,7 @@ static int upd64083_command(struct i2c_client *client, unsigned int cmd, void *a
 	{
 		struct v4l2_register *reg = arg;
 
-		if (reg->i2c_id != I2C_DRIVERID_UPD64083)
+		if (!v4l2_chip_match_i2c_client(client, reg->match_type, reg->match_chip))
 			return -EINVAL;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;

drivers/media/video/usbvision/usbvision-video.c

@@ -521,7 +521,7 @@ static int usbvision_v4l2_do_ioctl(struct inode *inode, struct file *file,
 			struct v4l2_register *reg = arg;
 			int errCode;
 
-			if (reg->i2c_id != 0)
+			if (!v4l2_chip_match_host(reg->match_type, reg->match_chip))
 				return -EINVAL;
 			if (!capable(CAP_SYS_ADMIN))
 				return -EPERM;
@@ -540,7 +540,7 @@ static int usbvision_v4l2_do_ioctl(struct inode *inode, struct file *file,
 
 			PDEBUG(DBG_IOCTL, "VIDIOC_DBG_%c_REGISTER reg=0x%02X, value=0x%02X",
 			       cmd == VIDIOC_DBG_G_REGISTER ? 'G' : 'S',
-			       (unsigned int)reg->reg, reg->val);
+			       (unsigned int)reg->reg, (unsigned int)reg->val);
 			return 0;
 		}
 #endif

drivers/media/video/v4l2-common.c

@@ -51,6 +51,7 @@
 #include <linux/mm.h>
 #include <linux/string.h>
 #include <linux/errno.h>
+#include <linux/i2c.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
 #include <asm/pgtable.h>
@@ -947,6 +948,32 @@ u32 v4l2_ctrl_next(const u32 * const * ctrl_classes, u32 id)
 	return **ctrl_classes;
 }
 
+int v4l2_chip_match_i2c_client(struct i2c_client *c, u32 match_type, u32 match_chip)
+{
+	switch (match_type) {
+	case V4L2_CHIP_MATCH_ALWAYS:
+		return 1;
+	case V4L2_CHIP_MATCH_I2C_DRIVER:
+		return (c != NULL && c->driver != NULL && c->driver->id == match_chip);
+	case V4L2_CHIP_MATCH_I2C_ADDR:
+		return (c != NULL && c->addr == match_chip);
+	default:
+		return 0;
+	}
+}
+
+int v4l2_chip_match_host(u32 match_type, u32 match_chip)
+{
+	switch (match_type) {
+	case V4L2_CHIP_MATCH_ALWAYS:
+		return 1;
+	case V4L2_CHIP_MATCH_HOST:
+		return match_chip == 0;
+	default:
+		return 0;
+	}
+}
+
 /* ----------------------------------------------------------------- */
 
 EXPORT_SYMBOL(v4l2_norm_to_name);
@@ -970,6 +997,9 @@ EXPORT_SYMBOL(v4l2_ctrl_query_menu);
 EXPORT_SYMBOL(v4l2_ctrl_query_fill);
 EXPORT_SYMBOL(v4l2_ctrl_query_fill_std);
 
+EXPORT_SYMBOL(v4l2_chip_match_i2c_client);
+EXPORT_SYMBOL(v4l2_chip_match_host);
+
 /*
  * Local variables:
  * c-basic-offset: 8

include/linux/videodev2.h

@@ -1306,10 +1306,17 @@ struct v4l2_streamparm
  */
 
 /* VIDIOC_DBG_G_REGISTER and VIDIOC_DBG_S_REGISTER */
+
+#define V4L2_CHIP_MATCH_ALWAYS     0  /* Match always (match_chip is not used) */
+#define V4L2_CHIP_MATCH_HOST       1  /* Match against chip ID on host (0 for the host) */
+#define V4L2_CHIP_MATCH_I2C_DRIVER 2  /* Match against I2C driver ID */
+#define V4L2_CHIP_MATCH_I2C_ADDR   3  /* Match against I2C 7-bit address */
+
 struct v4l2_register {
+	__u32 match_type; /* Match type */
+	__u32 match_chip; /* Match this chip, meaning determined by match_type */
 	__u64 reg;
-	__u32 i2c_id; /* I2C driver ID of the I2C chip, or 0 for the host */
-	__u32 val;
+	__u64 val;
 };
 
 /*

include/media/v4l2-common.h

@@ -94,6 +94,14 @@ u32 v4l2_ctrl_next(const u32 * const *ctrl_classes, u32 id);
 
 /* ------------------------------------------------------------------------- */
 
+/* Register/chip ident helper function */
+
+struct i2c_client; /* forward reference */
+int v4l2_chip_match_i2c_client(struct i2c_client *c, u32 id_type, u32 chip_id);
+int v4l2_chip_match_host(u32 id_type, u32 chip_id);
+
+/* ------------------------------------------------------------------------- */
+
 /* Internal ioctls */
 
 /* VIDIOC_INT_DECODE_VBI_LINE */