V4L/DVB (5306): Add support for VIDIOC_G_CHIP_IDENT

VIDIOC_G_CHIP_IDENT improves debugging of card problems: it can be
used to detect which chips are on the board and based on that information
selected register dumps can be made, making it easy to debug complicated
media chips containing tens or hundreds of registers.
This ioctl replaces the internal VIDIOC_INT_G_CHIP_IDENT ioctl.

Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/cafe_ccic.c

···
 #include <linux/spinlock.h>
 #include <linux/videodev2.h>
 #include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
 #include <linux/device.h>
 #include <linux/wait.h>
 #include <linux/list.h>
···
 	struct tasklet_struct s_tasklet;
 
 	/* Current operating parameters */
-	enum v4l2_chip_ident sensor_type;		/* Currently ov7670 only */
+	u32 sensor_type;		/* Currently ov7670 only */
 	struct v4l2_pix_format pix_format;
 
 	/* Locks */
···
  */
 static int cafe_cam_init(struct cafe_camera *cam)
 {
+	struct v4l2_chip_ident chip = { V4L2_CHIP_MATCH_I2C_ADDR, 0, 0, 0 };
 	int ret;
 
 	mutex_lock(&cam->s_mutex);
···
 	ret = __cafe_cam_reset(cam);
 	if (ret)
 		goto out;
-	ret = __cafe_cam_cmd(cam, VIDIOC_INT_G_CHIP_IDENT, &cam->sensor_type);
+	chip.match_chip = cam->sensor->addr;
+	ret = __cafe_cam_cmd(cam, VIDIOC_G_CHIP_IDENT, &chip);
 	if (ret)
 		goto out;
+	cam->sensor_type = chip.ident;
 //	if (cam->sensor->addr != OV7xx0_SID) {
 	if (cam->sensor_type != V4L2_IDENT_OV7670) {
 		cam_err(cam, "Unsupported sensor type %d", cam->sensor->addr);

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

···
 #include <linux/videodev2.h>
 #include <linux/i2c.h>
 #include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
 #include <media/cx25840.h>
 
 #include "cx25840-core.h"
···
 			cx25840_initialize(client, 0);
 		break;
 
-	case VIDIOC_INT_G_CHIP_IDENT:
-		*(enum v4l2_chip_ident *)arg = state->id;
-		break;
+	case VIDIOC_G_CHIP_IDENT:
+		return v4l2_chip_ident_i2c_client(client, arg, state->id, state->rev);
 
 	default:
 		return -EINVAL;
···
 {
 	struct i2c_client *client;
 	struct cx25840_state *state;
-	enum v4l2_chip_ident id;
+	u32 id;
 	u16 device_id;
 
 	/* Check if the adapter supports the needed features
···
 	state->audmode = V4L2_TUNER_MODE_LANG1;
 	state->vbi_line_offset = 8;
 	state->id = id;
+	state->rev = device_id;
 
 	i2c_attach_client(client);
 

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

···
 	u32 audclk_freq;
 	int audmode;
 	int vbi_line_offset;
-	enum v4l2_chip_ident id;
+	u32 id;
+	u32 rev;
 	int is_cx25836;
 };
 

drivers/media/video/ov7670.c

···
 #include <linux/delay.h>
 #include <linux/videodev.h>
 #include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
 #include <linux/i2c.h>
 
 
···
 		void *arg)
 {
 	switch (cmd) {
-	case VIDIOC_INT_G_CHIP_IDENT:
-		* (enum v4l2_chip_ident *) arg = V4L2_IDENT_OV7670;
-		return 0;
+	case VIDIOC_G_CHIP_IDENT:
+		return v4l2_chip_ident_i2c_client(client, arg, V4L2_IDENT_OV7670, 0);
 
 	case VIDIOC_INT_RESET:
 		ov7670_reset(client);

drivers/media/video/saa7115.c

···
 #include <linux/i2c.h>
 #include <linux/videodev2.h>
 #include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
 #include <media/saa7115.h>
 #include <asm/div64.h>
 
···
 	int sat;
 	int width;
 	int height;
-	enum v4l2_chip_ident ident;
+	u32 ident;
 	u32 audclk_freq;
 	u32 crystal_freq;
 	u8 ucgc;
···
 static int saa711x_command(struct i2c_client *client, unsigned int cmd, void *arg)
 {
 	struct saa711x_state *state = i2c_get_clientdata(client);
-	int *iarg = arg;
 
 	/* ioctls to allow direct access to the saa7115 registers for testing */
 	switch (cmd) {
···
 	}
 #endif
 
-	case VIDIOC_INT_G_CHIP_IDENT:
-		*iarg = state->ident;
-		break;
+	case VIDIOC_G_CHIP_IDENT:
+		return v4l2_chip_ident_i2c_client(client, arg, state->ident, 0);
 
 	default:
 		return -EINVAL;

drivers/media/video/saa7127.c

···
 #include <linux/i2c.h>
 #include <linux/videodev2.h>
 #include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
 #include <media/saa7127.h>
 
 static int debug = 0;
···
 
 struct saa7127_state {
 	v4l2_std_id std;
-	enum v4l2_chip_ident ident;
+	u32 ident;
 	enum saa7127_input_type input_type;
 	enum saa7127_output_type output_type;
 	int video_enable;
···
 		break;
 	}
 
-	case VIDIOC_INT_G_CHIP_IDENT:
-		*(enum v4l2_chip_ident *)arg = state->ident;
-		break;
+	case VIDIOC_G_CHIP_IDENT:
+		return v4l2_chip_ident_i2c_client(client, arg, state->ident, 0);
 
 	default:
 		return -EINVAL;

drivers/media/video/v4l2-common.c

···
 #include <linux/video_decoder.h>
 #define __OLD_VIDIOC_ /* To allow fixing old calls*/
 #include <media/v4l2-common.h>
+#include <media/v4l2-chip-ident.h>
 
 #ifdef CONFIG_KMOD
 #include <linux/kmod.h>
···
 
 	[_IOC_NR(VIDIOC_DBG_S_REGISTER)]   = "VIDIOC_DBG_S_REGISTER",
 	[_IOC_NR(VIDIOC_DBG_G_REGISTER)]   = "VIDIOC_DBG_G_REGISTER",
+
+	[_IOC_NR(VIDIOC_G_CHIP_IDENT)]     = "VIDIOC_G_CHIP_IDENT",
 #endif
 };
 #define V4L2_IOCTLS ARRAY_SIZE(v4l2_ioctls)
···
 	[_IOC_NR(VIDIOC_INT_DECODE_VBI_LINE)]  = "VIDIOC_INT_DECODE_VBI_LINE",
 	[_IOC_NR(VIDIOC_INT_S_VBI_DATA)]       = "VIDIOC_INT_S_VBI_DATA",
 	[_IOC_NR(VIDIOC_INT_G_VBI_DATA)]       = "VIDIOC_INT_G_VBI_DATA",
-	[_IOC_NR(VIDIOC_INT_G_CHIP_IDENT)]     = "VIDIOC_INT_G_CHIP_IDENT",
 	[_IOC_NR(VIDIOC_INT_I2S_CLOCK_FREQ)]   = "VIDIOC_INT_I2S_CLOCK_FREQ",
 	[_IOC_NR(VIDIOC_INT_S_STANDBY)]        = "VIDIOC_INT_S_STANDBY",
 	[_IOC_NR(VIDIOC_INT_S_AUDIO_ROUTING)]  = "VIDIOC_INT_S_AUDIO_ROUTING",
···
 	}
 }
 
+int v4l2_chip_ident_i2c_client(struct i2c_client *c, struct v4l2_chip_ident *chip,
+		u32 ident, u32 revision)
+{
+	if (!v4l2_chip_match_i2c_client(c, chip->match_type, chip->match_chip))
+		return 0;
+	if (chip->ident == V4L2_IDENT_NONE) {
+		chip->ident = ident;
+		chip->revision = revision;
+	}
+	else {
+		chip->ident = V4L2_IDENT_AMBIGUOUS;
+		chip->revision = 0;
+	}
+	return 0;
+}
+
 int v4l2_chip_match_host(u32 match_type, u32 match_chip)
 {
 	switch (match_type) {
···
 EXPORT_SYMBOL(v4l2_ctrl_query_fill_std);
 
 EXPORT_SYMBOL(v4l2_chip_match_i2c_client);
+EXPORT_SYMBOL(v4l2_chip_ident_i2c_client);
 EXPORT_SYMBOL(v4l2_chip_match_host);
 
 /*

drivers/media/video/videodev.c

···
 		break;
 	}
 #endif
+	case VIDIOC_G_CHIP_IDENT:
+	{
+		struct v4l2_chip_ident *p=arg;
+		if (!vfd->vidioc_g_chip_ident)
+			break;
+		ret=vfd->vidioc_g_chip_ident(file, fh, p);
+		if (!ret)
+			dbgarg (cmd, "chip_ident=%u, revision=0x%x\n", p->ident, p->revision);
+		break;
+	}
 	} /* switch */
 
 	if (vfd->debug & V4L2_DEBUG_IOCTL_ARG) {

include/linux/videodev2.h

···
 	__u64 val;
 };
 
+/* VIDIOC_G_CHIP_IDENT */
+struct v4l2_chip_ident {
+	__u32 match_type;  /* Match type */
+	__u32 match_chip;  /* Match this chip, meaning determined by match_type */
+	__u32 ident;       /* chip identifier as specified in <media/v4l2-chip-ident.h> */
+	__u32 revision;    /* chip revision, chip specific */
+};
+
 /*
  *	I O C T L   C O D E S   F O R   V I D E O   D E V I C E S
  *
···
 /* Experimental, only implemented if CONFIG_VIDEO_ADV_DEBUG is defined */
 #define	VIDIOC_DBG_S_REGISTER 	_IOW  ('V', 79, struct v4l2_register)
 #define	VIDIOC_DBG_G_REGISTER 	_IOWR ('V', 80, struct v4l2_register)
+
+#define VIDIOC_G_CHIP_IDENT     _IOWR ('V', 81, struct v4l2_chip_ident)
 #endif
 
 #ifdef __OLD_VIDIOC_

include/media/v4l2-chip-ident.h

···
+/*
+    v4l2 chip identifiers header
+
+    This header provides a list of chip identifiers that can be returned
+    through the VIDIOC_G_CHIP_IDENT ioctl.
+
+    Copyright (C) 2007 Hans Verkuil <[e-mail]>
+
+    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef V4L2_CHIP_IDENT_H_
+#define V4L2_CHIP_IDENT_H_
+
+/* VIDIOC_G_CHIP_IDENT: identifies the actual chip installed on the board */
+enum {
+	/* general idents: reserved range 0-49 */
+	V4L2_IDENT_NONE      = 0,       /* No chip matched */
+	V4L2_IDENT_AMBIGUOUS = 1,       /* Match too general, multiple chips matched */
+	V4L2_IDENT_UNKNOWN   = 2,       /* Chip found, but cannot identify */
+
+	/* module saa7110: just ident= 100 */
+	V4L2_IDENT_SAA7110 = 100,
+
+	/* module saa7111: just ident= 101 */
+	V4L2_IDENT_SAA7111 = 101,
+
+	/* module saa7115: reserved range 102-149 */
+	V4L2_IDENT_SAA7113 = 103,
+	V4L2_IDENT_SAA7114 = 104,
+	V4L2_IDENT_SAA7115 = 105,
+	V4L2_IDENT_SAA7118 = 108,
+
+	/* module saa7127: reserved range 150-199 */
+	V4L2_IDENT_SAA7127 = 157,
+	V4L2_IDENT_SAA7129 = 159,
+
+	/* module cx25840: reserved range 200-249 */
+	V4L2_IDENT_CX25836 = 236,
+	V4L2_IDENT_CX25837 = 237,
+	V4L2_IDENT_CX25840 = 240,
+	V4L2_IDENT_CX25841 = 241,
+	V4L2_IDENT_CX25842 = 242,
+	V4L2_IDENT_CX25843 = 243,
+
+	/* OmniVision sensors - range 250-299 */
+	V4L2_IDENT_OV7670 = 250,
+};
+
+#endif

include/media/v4l2-common.h

···
 
 struct i2c_client; /* forward reference */
 int v4l2_chip_match_i2c_client(struct i2c_client *c, u32 id_type, u32 chip_id);
+int v4l2_chip_ident_i2c_client(struct i2c_client *c, struct v4l2_chip_ident *chip,
+		u32 ident, u32 revision);
 int v4l2_chip_match_host(u32 id_type, u32 chip_id);
 
 /* ------------------------------------------------------------------------- */
···
 				   On exit points to the start of the payload. */
 	u32 line;		/* Line number of the sliced VBI data (1-23) */
 	u32 type;		/* VBI service type (V4L2_SLICED_*). 0 if no service found */
-};
-
-/* VIDIOC_INT_G_CHIP_IDENT: identifies the actual chip installed on the board */
-enum v4l2_chip_ident {
-	/* general idents: reserved range 0-49 */
-	V4L2_IDENT_UNKNOWN = 0,
-
-	/* module saa7110: just ident= 100 */
-	V4L2_IDENT_SAA7110 = 100,
-
-	/* module saa7111: just ident= 101 */
-	V4L2_IDENT_SAA7111 = 101,
-
-	/* module saa7115: reserved range 102-149 */
-	V4L2_IDENT_SAA7113 = 103,
-	V4L2_IDENT_SAA7114 = 104,
-	V4L2_IDENT_SAA7115 = 105,
-	V4L2_IDENT_SAA7118 = 108,
-
-	/* module saa7127: reserved range 150-199 */
-	V4L2_IDENT_SAA7127 = 157,
-	V4L2_IDENT_SAA7129 = 159,
-
-	/* module cx25840: reserved range 200-249 */
-	V4L2_IDENT_CX25836 = 236,
-	V4L2_IDENT_CX25837 = 237,
-	V4L2_IDENT_CX25840 = 240,
-	V4L2_IDENT_CX25841 = 241,
-	V4L2_IDENT_CX25842 = 242,
-	V4L2_IDENT_CX25843 = 243,
-
-	/* OmniVision sensors - range 250-299 */
-	V4L2_IDENT_OV7670 = 250,
 };
 
 /* audio ioctls */
···
    you must fill in the 'id' member and the 'field' member (to determine
    whether CC data from the first or second field should be obtained). */
 #define VIDIOC_INT_G_VBI_DATA 		_IOWR('d', 106, struct v4l2_sliced_vbi_data)
-
-/* Returns the chip identifier or V4L2_IDENT_UNKNOWN if no identification can
-   be made. */
-#define VIDIOC_INT_G_CHIP_IDENT		_IOR ('d', 107, enum v4l2_chip_ident)
 
 /* Sets I2S speed in bps. This is used to provide a standard way to select I2S
    clock used by driving digital audio streams at some board designs.

include/media/v4l2-dev.h

···
 	int (*vidioc_s_register)       (struct file *file, void *fh,
 					struct v4l2_register *reg);
 #endif
+	int (*vidioc_g_chip_ident)     (struct file *file, void *fh,
+					struct v4l2_chip_ident *chip);
 
 
 #ifdef OBSOLETE_OWNER /* to be removed soon */