V4L/DVB (12125): v4l2: add new s_config subdev ops and v4l2_i2c_new_subdev_cfg/board calls

Add a new s_config core ops call: this is called with the irq and platform
data to be used to initialize the subdev.

Added new v4l2_i2c_new_subdev_cfg and v4l2_i2c_new_subdev_board calls
that allows you to pass these new arguments.

The existing v4l2_i2c_new_subdev functions were modified to also call
s_config.

In the future the existing v4l2_i2c_new_subdev functions will be replaced
by a single v4l2_i2c_new_subdev function similar to v4l2_i2c_new_subdev_cfg
but without the irq and platform_data arguments.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 127 insertions, 1 deletions

diff --git a/drivers/media/video/v4l2-common.c b/drivers/media/video/v4l2-common.c
index f96475626da7..e7b443c116f0 100644
--- a/drivers/media/video/v4l2-common.c
+++ b/drivers/media/video/v4l2-common.c
@@ -802,6 +802,17 @@ struct v4l2_subdev *v4l2_i2c_new_subdev(struct v4l2_device *v4l2_dev,
         /* Decrease the module use count to match the first try_module_get. */
         module_put(client->driver->driver.owner);
 
+        if (sd) {
+                /* We return errors from v4l2_subdev_call only if we have the
+                   callback as the .s_config is not mandatory */
+                int err = v4l2_subdev_call(sd, core, s_config, 0, NULL);
+
+                if (err && err != -ENOIOCTLCMD) {
+                        v4l2_device_unregister_subdev(sd);
+                        sd = NULL;
+                }
+        }
+
 error:
         /* If we have a client but no subdev, then something went wrong and
            we must unregister the client. */
@@ -852,6 +863,17 @@ struct v4l2_subdev *v4l2_i2c_new_probed_subdev(struct v4l2_device *v4l2_dev,
         /* Decrease the module use count to match the first try_module_get. */
         module_put(client->driver->driver.owner);
 
+        if (sd) {
+                /* We return errors from v4l2_subdev_call only if we have the
+                   callback as the .s_config is not mandatory */
+                int err = v4l2_subdev_call(sd, core, s_config, 0, NULL);
+
+                if (err && err != -ENOIOCTLCMD) {
+                        v4l2_device_unregister_subdev(sd);
+                        sd = NULL;
+                }
+        }
+
 error:
         /* If we have a client but no subdev, then something went wrong and
            we must unregister the client. */
@@ -872,6 +894,89 @@ struct v4l2_subdev *v4l2_i2c_new_probed_subdev_addr(struct v4l2_device *v4l2_dev
 }
 EXPORT_SYMBOL_GPL(v4l2_i2c_new_probed_subdev_addr);
 
+/* Load an i2c sub-device. */
+struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
+                struct i2c_adapter *adapter, const char *module_name,
+                struct i2c_board_info *info, const unsigned short *probe_addrs)
+{
+        struct v4l2_subdev *sd = NULL;
+        struct i2c_client *client;
+
+        BUG_ON(!v4l2_dev);
+
+        if (module_name)
+                request_module(module_name);
+
+        /* Create the i2c client */
+        if (info->addr == 0 && probe_addrs)
+                client = i2c_new_probed_device(adapter, info, probe_addrs);
+        else
+                client = i2c_new_device(adapter, info);
+
+        /* Note: by loading the module first we are certain that c->driver
+           will be set if the driver was found. If the module was not loaded
+           first, then the i2c core tries to delay-load the module for us,
+           and then c->driver is still NULL until the module is finally
+           loaded. This delay-load mechanism doesn't work if other drivers
+           want to use the i2c device, so explicitly loading the module
+           is the best alternative. */
+        if (client == NULL || client->driver == NULL)
+                goto error;
+
+        /* Lock the module so we can safely get the v4l2_subdev pointer */
+        if (!try_module_get(client->driver->driver.owner))
+                goto error;
+        sd = i2c_get_clientdata(client);
+
+        /* Register with the v4l2_device which increases the module's
+           use count as well. */
+        if (v4l2_device_register_subdev(v4l2_dev, sd))
+                sd = NULL;
+        /* Decrease the module use count to match the first try_module_get. */
+        module_put(client->driver->driver.owner);
+
+        if (sd) {
+                /* We return errors from v4l2_subdev_call only if we have the
+                   callback as the .s_config is not mandatory */
+                int err = v4l2_subdev_call(sd, core, s_config,
+                                info->irq, info->platform_data);
+
+                if (err && err != -ENOIOCTLCMD) {
+                        v4l2_device_unregister_subdev(sd);
+                        sd = NULL;
+                }
+        }
+
+error:
+        /* If we have a client but no subdev, then something went wrong and
+           we must unregister the client. */
+        if (client && sd == NULL)
+                i2c_unregister_device(client);
+        return sd;
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_board);
+
+struct v4l2_subdev *v4l2_i2c_new_subdev_cfg(struct v4l2_device *v4l2_dev,
+                struct i2c_adapter *adapter,
+                const char *module_name, const char *client_type,
+                int irq, void *platform_data,
+                u8 addr, const unsigned short *probe_addrs)
+{
+        struct i2c_board_info info;
+
+        /* Setup the i2c board info with the device type and
+           the device address. */
+        memset(&info, 0, sizeof(info));
+        strlcpy(info.type, client_type, sizeof(info.type));
+        info.addr = addr;
+        info.irq = irq;
+        info.platform_data = platform_data;
+
+        return v4l2_i2c_new_subdev_board(v4l2_dev, adapter, module_name,
+                        &info, probe_addrs);
+}
+EXPORT_SYMBOL_GPL(v4l2_i2c_new_subdev_cfg);
+
 /* Return i2c client address of v4l2_subdev. */
 unsigned short v4l2_i2c_subdev_addr(struct v4l2_subdev *sd)
 {
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index c48c24e4d0fa..95f4364322eb 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -153,6 +153,22 @@ struct v4l2_subdev *v4l2_i2c_new_probed_subdev(struct v4l2_device *v4l2_dev,
 struct v4l2_subdev *v4l2_i2c_new_probed_subdev_addr(struct v4l2_device *v4l2_dev,
                 struct i2c_adapter *adapter,
                 const char *module_name, const char *client_type, u8 addr);
+
+/* Load an i2c module and return an initialized v4l2_subdev struct.
+   Only call request_module if module_name != NULL.
+   The client_type argument is the name of the chip that's on the adapter. */
+struct v4l2_subdev *v4l2_i2c_new_subdev_cfg(struct v4l2_device *v4l2_dev,
+                struct i2c_adapter *adapter,
+                const char *module_name, const char *client_type,
+                int irq, void *platform_data,
+                u8 addr, const unsigned short *probe_addrs);
+
+struct i2c_board_info;
+
+struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
+                struct i2c_adapter *adapter, const char *module_name,
+                struct i2c_board_info *info, const unsigned short *probe_addrs);
+
 /* Initialize an v4l2_subdev with data from an i2c_client struct */
 void v4l2_i2c_subdev_init(struct v4l2_subdev *sd, struct i2c_client *client,
                 const struct v4l2_subdev_ops *ops);
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index a503e1cee78b..5dcb36785529 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -79,7 +79,11 @@ struct v4l2_decode_vbi_line {
    not yet implemented) since ops provide proper type-checking.
  */
 
-/* init: initialize the sensor registors to some sort of reasonable default
+/* s_config: if set, then it is always called by the v4l2_i2c_new_subdev*
+        functions after the v4l2_subdev was registered. It is used to pass
+        platform data to the subdev which can be used during initialization.
+
+   init: initialize the sensor registors to some sort of reasonable default
         values. Do not use for new drivers and should be removed in existing
         drivers.
 
@@ -96,6 +100,7 @@ struct v4l2_decode_vbi_line {
 struct v4l2_subdev_core_ops {
         int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip);
         int (*log_status)(struct v4l2_subdev *sd);
+        int (*s_config)(struct v4l2_subdev *sd, int irq, void *platform_data);
         int (*init)(struct v4l2_subdev *sd, u32 val);
         int (*load_fw)(struct v4l2_subdev *sd);
         int (*reset)(struct v4l2_subdev *sd, u32 val);