/* V4L2 device support. 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 */ #include <linux/types.h> #include <linux/ioctl.h> #include <linux/i2c.h> #if defined(CONFIG_SPI) #include <linux/spi/spi.h> #endif #include <linux/videodev2.h> #include <media/v4l2-device.h> int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev) { if (v4l2_dev == NULL) return -EINVAL; INIT_LIST_HEAD(&v4l2_dev->subdevs); spin_lock_init(&v4l2_dev->lock); v4l2_dev->dev = dev; if (dev == NULL) { /* If dev == NULL, then name must be filled in by the caller */ WARN_ON(!v4l2_dev->name[0]); return 0; } /* Set name to driver name + device name if it is empty. */ if (!v4l2_dev->name[0]) snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s", dev->driver->name, dev_name(dev)); if (dev_get_drvdata(dev)) v4l2_warn(v4l2_dev, "Non-NULL drvdata on register\n"); dev_set_drvdata(dev, v4l2_dev); return 0; } EXPORT_SYMBOL_GPL(v4l2_device_register); int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename, atomic_t *instance) { int num = atomic_inc_return(instance) - 1; int len = strlen(basename); if (basename[len - 1] >= '0' && basename[len - 1] <= '9') snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s-%d", basename, num); else snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s%d", basename, num); return num; } EXPORT_SYMBOL_GPL(v4l2_device_set_name); void v4l2_device_disconnect(struct v4l2_device *v4l2_dev) { if (v4l2_dev->dev) { dev_set_drvdata(v4l2_dev->dev, NULL); v4l2_dev->dev = NULL; } } EXPORT_SYMBOL_GPL(v4l2_device_disconnect); void v4l2_device_unregister(struct v4l2_device *v4l2_dev) { struct v4l2_subdev *sd, *next; if (v4l2_dev == NULL) return; v4l2_device_disconnect(v4l2_dev); /* Unregister subdevs */ list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) { v4l2_device_unregister_subdev(sd); #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE)) if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) { struct i2c_client *client = v4l2_get_subdevdata(sd); /* We need to unregister the i2c client explicitly. We cannot rely on i2c_del_adapter to always unregister clients for us, since if the i2c bus is a platform bus, then it is never deleted. */ if (client) i2c_unregister_device(client); } #endif #if defined(CONFIG_SPI) if (sd->flags & V4L2_SUBDEV_FL_IS_SPI) { struct spi_device *spi = v4l2_get_subdevdata(sd); if (spi) spi_unregister_device(spi); } #endif } } EXPORT_SYMBOL_GPL(v4l2_device_unregister); int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, struct v4l2_subdev *sd) { /* Check for valid input */ if (v4l2_dev == NULL || sd == NULL || !sd->name[0]) return -EINVAL; /* Warn if we apparently re-register a subdev */ WARN_ON(sd->v4l2_dev != NULL); if (!try_module_get(sd->owner)) return -ENODEV; sd->v4l2_dev = v4l2_dev; spin_lock(&v4l2_dev->lock); list_add_tail(&sd->list, &v4l2_dev->subdevs); spin_unlock(&v4l2_dev->lock); return 0; } EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) { /* return if it isn't registered */ if (sd == NULL || sd->v4l2_dev == NULL) return; spin_lock(&sd->v4l2_dev->lock); list_del(&sd->list); spin_unlock(&sd->v4l2_dev->lock); sd->v4l2_dev = NULL; module_put(sd->owner); } EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);