[media] bttv: add VIDIOC_DBG_G_CHIP_IDENT

VIDIOC_DBG_G_CHIP_IDENT is a prerequisite for the G/S_REGISTER ioctls.
In addition, add support to call G/S_REGISTER for supporting i2c devices.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 47 insertions, 4 deletions

diff --git a/drivers/media/pci/bt8xx/bttv-driver.c b/drivers/media/pci/bt8xx/bttv-driver.c
index cc7f58f94cde..b36d67577535 100644
--- a/drivers/media/pci/bt8xx/bttv-driver.c
+++ b/drivers/media/pci/bt8xx/bttv-driver.c
@@ -49,6 +49,7 @@
 #include "bttvp.h"
 #include <media/v4l2-common.h>
 #include <media/v4l2-ioctl.h>
+#include <media/v4l2-chip-ident.h>
 #include <media/tvaudio.h>
 #include <media/msp3400.h>
 
@@ -2059,6 +2060,28 @@ static int bttv_log_status(struct file *file, void *f)
         return 0;
 }
 
+static int bttv_g_chip_ident(struct file *file, void *f, struct v4l2_dbg_chip_ident *chip)
+{
+        struct bttv_fh *fh  = f;
+        struct bttv *btv = fh->btv;
+
+        chip->ident = V4L2_IDENT_NONE;
+        chip->revision = 0;
+        if (chip->match.type == V4L2_CHIP_MATCH_HOST) {
+                if (v4l2_chip_match_host(&chip->match)) {
+                        chip->ident = btv->id;
+                        if (chip->ident == PCI_DEVICE_ID_FUSION879)
+                                chip->ident = V4L2_IDENT_BT879;
+                }
+                return 0;
+        }
+        if (chip->match.type != V4L2_CHIP_MATCH_I2C_DRIVER &&
+            chip->match.type != V4L2_CHIP_MATCH_I2C_ADDR)
+                return -EINVAL;
+        /* TODO: is this correct? */
+        return bttv_call_all_err(btv, core, g_chip_ident, chip);
+}
+
 #ifdef CONFIG_VIDEO_ADV_DEBUG
 static int bttv_g_register(struct file *file, void *f,
                                         struct v4l2_dbg_register *reg)
@@ -2069,8 +2092,12 @@ static int bttv_g_register(struct file *file, void *f,
         if (!capable(CAP_SYS_ADMIN))
                 return -EPERM;
 
-        if (!v4l2_chip_match_host(&reg->match))
-                return -EINVAL;
+        if (!v4l2_chip_match_host(&reg->match)) {
+                /* TODO: subdev errors should not be ignored, this should become a
+                   subdev helper function. */
+                bttv_call_all(btv, core, g_register, reg);
+                return 0;
+        }
 
         /* bt848 has a 12-bit register space */
         reg->reg &= 0xfff;
@@ -2089,8 +2116,12 @@ static int bttv_s_register(struct file *file, void *f,
         if (!capable(CAP_SYS_ADMIN))
                 return -EPERM;
 
-        if (!v4l2_chip_match_host(&reg->match))
-                return -EINVAL;
+        if (!v4l2_chip_match_host(&reg->match)) {
+                /* TODO: subdev errors should not be ignored, this should become a
+                   subdev helper function. */
+                bttv_call_all(btv, core, s_register, reg);
+                return 0;
+        }
 
         /* bt848 has a 12-bit register space */
         reg->reg &= 0xfff;
@@ -3394,6 +3425,7 @@ static const struct v4l2_ioctl_ops bttv_ioctl_ops = {
         .vidioc_s_frequency             = bttv_s_frequency,
         .vidioc_log_status              = bttv_log_status,
         .vidioc_querystd                = bttv_querystd,
+        .vidioc_g_chip_ident            = bttv_g_chip_ident,
 #ifdef CONFIG_VIDEO_ADV_DEBUG
         .vidioc_g_register              = bttv_g_register,
         .vidioc_s_register              = bttv_s_register,
diff --git a/drivers/media/pci/bt8xx/bttv.h b/drivers/media/pci/bt8xx/bttv.h
index 79a11240a590..6139ce26dc2c 100644
--- a/drivers/media/pci/bt8xx/bttv.h
+++ b/drivers/media/pci/bt8xx/bttv.h
@@ -359,6 +359,9 @@ void bttv_gpio_bits(struct bttv_core *core, u32 mask, u32 bits);
 #define bttv_call_all(btv, o, f, args...) \
         v4l2_device_call_all(&btv->c.v4l2_dev, 0, o, f, ##args)
 
+#define bttv_call_all_err(btv, o, f, args...) \
+        v4l2_device_call_until_err(&btv->c.v4l2_dev, 0, o, f, ##args)
+
 extern int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for);
 extern int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
                          unsigned char b2, int both);
diff --git a/include/media/v4l2-chip-ident.h b/include/media/v4l2-chip-ident.h
index 4ee125bae719..b5996f959a31 100644
--- a/include/media/v4l2-chip-ident.h
+++ b/include/media/v4l2-chip-ident.h
@@ -96,12 +96,20 @@ enum {
         /* module au0828 */
         V4L2_IDENT_AU0828 = 828,
 
+        /* module bttv: ident 848 + 849 */
+        V4L2_IDENT_BT848 = 848,
+        V4L2_IDENT_BT849 = 849,
+
         /* module bt856: just ident 856 */
         V4L2_IDENT_BT856 = 856,
 
         /* module bt866: just ident 866 */
         V4L2_IDENT_BT866 = 866,
 
+        /* module bttv: ident 878 + 879 */
+        V4L2_IDENT_BT878 = 878,
+        V4L2_IDENT_BT879 = 879,
+
         /* module ks0127: reserved range 1120-1129 */
         V4L2_IDENT_KS0122S = 1122,
         V4L2_IDENT_KS0127  = 1127,