V4L/DVB (9820): v4l2: add v4l2_device and v4l2_subdev structs to the v4l2 framework.
Start implementing a proper v4l2 framework as discussed during the
Linux Plumbers Conference 2008.
Introduces v4l2_device (for device instances) and v4l2_subdev (representing
sub-device instances).
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Reviewed-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: Andy Walls <awalls@radix.net>
Reviewed-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h
new file mode 100644
index 0000000..97b283a
--- /dev/null
+++ b/include/media/v4l2-device.h
@@ -0,0 +1,109 @@
+/*
+ V4L2 device support header.
+
+ Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
+
+ 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_DEVICE_H
+#define _V4L2_DEVICE_H
+
+#include <media/v4l2-subdev.h>
+
+/* Each instance of a V4L2 device should create the v4l2_device struct,
+ either stand-alone or embedded in a larger struct.
+
+ It allows easy access to sub-devices (see v4l2-subdev.h) and provides
+ basic V4L2 device-level support.
+ */
+
+#define V4L2_DEVICE_NAME_SIZE (BUS_ID_SIZE + 16)
+
+struct v4l2_device {
+ /* dev->driver_data points to this struct */
+ struct device *dev;
+ /* used to keep track of the registered subdevs */
+ struct list_head subdevs;
+ /* lock this struct; can be used by the driver as well if this
+ struct is embedded into a larger struct. */
+ spinlock_t lock;
+ /* unique device name, by default the driver name + bus ID */
+ char name[V4L2_DEVICE_NAME_SIZE];
+};
+
+/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev */
+int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
+/* Set v4l2_dev->dev->driver_data to NULL and unregister all sub-devices */
+void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
+
+/* Register a subdev with a v4l2 device. While registered the subdev module
+ is marked as in-use. An error is returned if the module is no longer
+ loaded when you attempt to register it. */
+int __must_check v4l2_device_register_subdev(struct v4l2_device *dev, struct v4l2_subdev *sd);
+/* Unregister a subdev with a v4l2 device. Can also be called if the subdev
+ wasn't registered. In that case it will do nothing. */
+void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
+
+/* Iterate over all subdevs. */
+#define v4l2_device_for_each_subdev(sd, dev) \
+ list_for_each_entry(sd, &(dev)->subdevs, list)
+
+/* Call the specified callback for all subdevs matching the condition.
+ Ignore any errors. Note that you cannot add or delete a subdev
+ while walking the subdevs list. */
+#define __v4l2_device_call_subdevs(dev, cond, o, f, args...) \
+ do { \
+ struct v4l2_subdev *sd; \
+ \
+ list_for_each_entry(sd, &(dev)->subdevs, list) \
+ if ((cond) && sd->ops->o && sd->ops->o->f) \
+ sd->ops->o->f(sd , ##args); \
+ } while (0)
+
+/* Call the specified callback for all subdevs matching the condition.
+ If the callback returns an error other than 0 or -ENOIOCTLCMD, then
+ return with that error code. Note that you cannot add or delete a
+ subdev while walking the subdevs list. */
+#define __v4l2_device_call_subdevs_until_err(dev, cond, o, f, args...) \
+({ \
+ struct v4l2_subdev *sd; \
+ int err = 0; \
+ \
+ list_for_each_entry(sd, &(dev)->subdevs, list) { \
+ if ((cond) && sd->ops->o && sd->ops->o->f) \
+ err = sd->ops->o->f(sd , ##args); \
+ if (err && err != -ENOIOCTLCMD) \
+ break; \
+ } \
+ (err == -ENOIOCTLCMD) ? 0 : err; \
+})
+
+/* Call the specified callback for all subdevs matching grp_id (if 0, then
+ match them all). Ignore any errors. Note that you cannot add or delete
+ a subdev while walking the subdevs list. */
+#define v4l2_device_call_all(dev, grp_id, o, f, args...) \
+ __v4l2_device_call_subdevs(dev, \
+ !(grp_id) || sd->grp_id == (grp_id), o, f , ##args)
+
+/* Call the specified callback for all subdevs matching grp_id (if 0, then
+ match them all). If the callback returns an error other than 0 or
+ -ENOIOCTLCMD, then return with that error code. Note that you cannot
+ add or delete a subdev while walking the subdevs list. */
+#define v4l2_device_call_until_err(dev, grp_id, o, f, args...) \
+ __v4l2_device_call_subdevs_until_err(dev, \
+ !(grp_id) || sd->grp_id == (grp_id), o, f , ##args)
+
+#endif
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
new file mode 100644
index 0000000..bc9e0fb
--- /dev/null
+++ b/include/media/v4l2-subdev.h
@@ -0,0 +1,188 @@
+/*
+ V4L2 sub-device support header.
+
+ Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
+
+ 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_SUBDEV_H
+#define _V4L2_SUBDEV_H
+
+#include <media/v4l2-common.h>
+
+struct v4l2_device;
+struct v4l2_subdev;
+struct tuner_setup;
+
+/* Sub-devices are devices that are connected somehow to the main bridge
+ device. These devices are usually audio/video muxers/encoders/decoders or
+ sensors and webcam controllers.
+
+ Usually these devices are controlled through an i2c bus, but other busses
+ may also be used.
+
+ The v4l2_subdev struct provides a way of accessing these devices in a
+ generic manner. Most operations that these sub-devices support fall in
+ a few categories: core ops, audio ops, video ops and tuner ops.
+
+ More categories can be added if needed, although this should remain a
+ limited set (no more than approx. 8 categories).
+
+ Each category has its own set of ops that subdev drivers can implement.
+
+ A subdev driver can leave the pointer to the category ops NULL if
+ it does not implement them (e.g. an audio subdev will generally not
+ implement the video category ops). The exception is the core category:
+ this must always be present.
+
+ These ops are all used internally so it is no problem to change, remove
+ or add ops or move ops from one to another category. Currently these
+ ops are based on the original ioctls, but since ops are not limited to
+ one argument there is room for improvement here once all i2c subdev
+ drivers are converted to use these ops.
+ */
+
+/* Core ops: it is highly recommended to implement at least these ops:
+
+ g_chip_ident
+ log_status
+ g_register
+ s_register
+
+ This provides basic debugging support.
+
+ The ioctl ops is meant for generic ioctl-like commands. Depending on
+ the use-case it might be better to use subdev-specific ops (currently
+ not yet implemented) since ops provide proper type-checking.
+ */
+struct v4l2_subdev_core_ops {
+ int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_chip_ident *chip);
+ int (*log_status)(struct v4l2_subdev *sd);
+ int (*init)(struct v4l2_subdev *sd, u32 val);
+ int (*s_standby)(struct v4l2_subdev *sd, u32 standby);
+ int (*reset)(struct v4l2_subdev *sd, u32 val);
+ int (*s_gpio)(struct v4l2_subdev *sd, u32 val);
+ int (*queryctrl)(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc);
+ int (*g_ctrl)(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
+ int (*s_ctrl)(struct v4l2_subdev *sd, struct v4l2_control *ctrl);
+ int (*querymenu)(struct v4l2_subdev *sd, struct v4l2_querymenu *qm);
+ int (*ioctl)(struct v4l2_subdev *sd, int cmd, void *arg);
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+ int (*g_register)(struct v4l2_subdev *sd, struct v4l2_register *reg);
+ int (*s_register)(struct v4l2_subdev *sd, struct v4l2_register *reg);
+#endif
+};
+
+struct v4l2_subdev_tuner_ops {
+ int (*s_mode)(struct v4l2_subdev *sd, enum v4l2_tuner_type);
+ int (*s_radio)(struct v4l2_subdev *sd);
+ int (*s_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq);
+ int (*g_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq);
+ int (*g_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt);
+ int (*s_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt);
+ int (*s_std)(struct v4l2_subdev *sd, v4l2_std_id norm);
+ int (*s_type_addr)(struct v4l2_subdev *sd, struct tuner_setup *type);
+ int (*s_config)(struct v4l2_subdev *sd, const struct v4l2_priv_tun_config *config);
+};
+
+struct v4l2_subdev_audio_ops {
+ int (*s_clock_freq)(struct v4l2_subdev *sd, u32 freq);
+ int (*s_i2s_clock_freq)(struct v4l2_subdev *sd, u32 freq);
+ int (*s_routing)(struct v4l2_subdev *sd, const struct v4l2_routing *route);
+};
+
+struct v4l2_subdev_video_ops {
+ int (*s_routing)(struct v4l2_subdev *sd, const struct v4l2_routing *route);
+ int (*s_crystal_freq)(struct v4l2_subdev *sd, struct v4l2_crystal_freq *freq);
+ int (*decode_vbi_line)(struct v4l2_subdev *sd, struct v4l2_decode_vbi_line *vbi_line);
+ int (*s_vbi_data)(struct v4l2_subdev *sd, const struct v4l2_sliced_vbi_data *vbi_data);
+ int (*g_vbi_data)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_data *vbi_data);
+ int (*s_std_output)(struct v4l2_subdev *sd, v4l2_std_id std);
+ int (*s_stream)(struct v4l2_subdev *sd, int enable);
+ int (*s_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
+ int (*g_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);
+};
+
+struct v4l2_subdev_ops {
+ const struct v4l2_subdev_core_ops *core;
+ const struct v4l2_subdev_tuner_ops *tuner;
+ const struct v4l2_subdev_audio_ops *audio;
+ const struct v4l2_subdev_video_ops *video;
+};
+
+#define V4L2_SUBDEV_NAME_SIZE 32
+
+/* Each instance of a subdev driver should create this struct, either
+ stand-alone or embedded in a larger struct.
+ */
+struct v4l2_subdev {
+ struct list_head list;
+ struct module *owner;
+ struct v4l2_device *dev;
+ const struct v4l2_subdev_ops *ops;
+ /* name must be unique */
+ char name[V4L2_SUBDEV_NAME_SIZE];
+ /* can be used to group similar subdevs, value is driver-specific */
+ u32 grp_id;
+ /* pointer to private data */
+ void *priv;
+};
+
+static inline void v4l2_set_subdevdata(struct v4l2_subdev *sd, void *p)
+{
+ sd->priv = p;
+}
+
+static inline void *v4l2_get_subdevdata(const struct v4l2_subdev *sd)
+{
+ return sd->priv;
+}
+
+/* Convert an ioctl-type command to the proper v4l2_subdev_ops function call.
+ This is used by subdev modules that can be called by both old-style ioctl
+ commands and through the v4l2_subdev_ops.
+
+ The ioctl API of the subdev driver can call this function to call the
+ right ops based on the ioctl cmd and arg.
+
+ Once all subdev drivers have been converted and all drivers no longer
+ use the ioctl interface, then this function can be removed.
+ */
+int v4l2_subdev_command(struct v4l2_subdev *sd, unsigned cmd, void *arg);
+
+static inline void v4l2_subdev_init(struct v4l2_subdev *sd,
+ const struct v4l2_subdev_ops *ops)
+{
+ INIT_LIST_HEAD(&sd->list);
+ /* ops->core MUST be set */
+ BUG_ON(!ops || !ops->core);
+ sd->ops = ops;
+ sd->dev = NULL;
+ sd->name[0] = '\0';
+ sd->grp_id = 0;
+ sd->priv = NULL;
+}
+
+/* Call an ops of a v4l2_subdev, doing the right checks against
+ NULL pointers.
+
+ Example: err = v4l2_subdev_call(sd, core, g_chip_ident, &chip);
+ */
+#define v4l2_subdev_call(sd, o, f, args...) \
+ (!(sd) ? -ENODEV : (((sd) && (sd)->ops->o && (sd)->ops->o->f) ? \
+ (sd)->ops->o->f((sd) , ##args) : -ENOIOCTLCMD))
+
+#endif