From: Sakari Ailus Date: Wed, 18 Jul 2007 20:59:15 +0000 (-0300) Subject: V4L/DVB (5862): V4L: Add internal ioctl-like interface. X-Git-Tag: v2.6.24-rc1~1463^2~309 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9b5d0f1e6dd6b4a67d0851a1c5a4bcf9b0c2f258;p=linux-2.6 V4L/DVB (5862): V4L: Add internal ioctl-like interface. This patch adds an internal ioctl-like interface which can be used in situations where a single Video4Linux device is implemented by multiple device drivers. One master device controls one or more slave devices. The slaves provide Video4Linux ioctl-like interface for the use of the master. Only a handful of ioctls are implemented at the moment. More can (and should) be added as more functionality is required. Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index 10b4d44690..d35306daac 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -11,7 +11,8 @@ tuner-$(CONFIG_TUNER_TEA5761) += tea5761.o msp3400-objs := msp3400-driver.o msp3400-kthreads.o -obj-$(CONFIG_VIDEO_DEV) += videodev.o v4l2-common.o compat_ioctl32.o +obj-$(CONFIG_VIDEO_DEV) += videodev.o v4l2-common.o compat_ioctl32.o \ + v4l2-int-device.o ifeq ($(CONFIG_VIDEO_V4L1_COMPAT),y) obj-$(CONFIG_VIDEO_DEV) += v4l1-compat.o diff --git a/drivers/media/video/v4l2-int-device.c b/drivers/media/video/v4l2-int-device.c new file mode 100644 index 0000000000..7885d9b38c --- /dev/null +++ b/drivers/media/video/v4l2-int-device.c @@ -0,0 +1,154 @@ +/* + * drivers/media/video/v4l2-int-device.c + * + * V4L2 internal ioctl interface. + * + * Copyright (C) 2007 Nokia Corporation. + * + * Contact: Sakari Ailus + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * 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., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#include +#include +#include +#include + +#include + +static DEFINE_MUTEX(mutex); +static LIST_HEAD(int_list); + +static void v4l2_int_device_try_attach_all(void) +{ + struct list_head *head_master; + + list_for_each(head_master, &int_list) { + struct list_head *head_slave; + struct v4l2_int_device *m = + list_entry(head_master, struct v4l2_int_device, head); + + if (m->type != v4l2_int_type_master) + continue; + + list_for_each(head_slave, &int_list) { + struct v4l2_int_device *s = + list_entry(head_slave, + struct v4l2_int_device, head); + + if (s->type != v4l2_int_type_slave) + continue; + + /* Slave is connected? */ + if (s->u.slave->master) + continue; + + /* Slave wants to attach to master? */ + if (s->u.slave->attach_to[0] != 0 + && strncmp(m->name, s->u.slave->attach_to, + V4L2NAMESIZE)) + continue; + + if (!try_module_get(m->module)) + continue; + + if (m->u.master->attach(m, s)) { + module_put(m->module); + continue; + } + + s->u.slave->master = m; + } + } +} + +static int ioctl_sort_cmp(const void *a, const void *b) +{ + const struct v4l2_int_ioctl_desc *d1 = a, *d2 = b; + + if (d1->num > d2->num) + return 1; + + if (d1->num < d2->num) + return -1; + + return 0; +} + +int v4l2_int_device_register(struct v4l2_int_device *d) +{ + if (d->type == v4l2_int_type_slave) + sort(d->u.slave->ioctls, d->u.slave->num_ioctls, + sizeof(struct v4l2_int_ioctl_desc), + &ioctl_sort_cmp, NULL); + mutex_lock(&mutex); + list_add(&d->head, &int_list); + v4l2_int_device_try_attach_all(); + mutex_unlock(&mutex); + + return 0; +} + +void v4l2_int_device_unregister(struct v4l2_int_device *d) +{ + mutex_lock(&mutex); + list_del(&d->head); + if (d->type == v4l2_int_type_slave + && d->u.slave->master != NULL) { + d->u.slave->master->u.master->detach(d); + module_put(d->u.slave->master->module); + d->u.slave->master = NULL; + } + mutex_unlock(&mutex); +} + +static int no_such_ioctl(struct v4l2_int_device *d) +{ + return -EINVAL; +} + +/* Adapted from search_extable in extable.c. */ +static v4l2_int_ioctl_func *find_ioctl(struct v4l2_int_slave *slave, int cmd) +{ + const struct v4l2_int_ioctl_desc *first = slave->ioctls; + const struct v4l2_int_ioctl_desc *last = + first + slave->num_ioctls - 1; + + while (first <= last) { + const struct v4l2_int_ioctl_desc *mid; + + mid = (last - first) / 2 + first; + + if (mid->num < cmd) + first = mid + 1; + else if (mid->num > cmd) + last = mid - 1; + else + return mid->func; + } + + return &no_such_ioctl; +} + +int v4l2_int_ioctl_0(struct v4l2_int_device *d, int cmd) +{ + return ((v4l2_int_ioctl_func_0 *)find_ioctl(d->u.slave, cmd))(d); +} + +int v4l2_int_ioctl_1(struct v4l2_int_device *d, int cmd, void *arg) +{ + return ((v4l2_int_ioctl_func_1 *)find_ioctl(d->u.slave, cmd))(d, arg); +} diff --git a/include/media/v4l2-int-device.h b/include/media/v4l2-int-device.h new file mode 100644 index 0000000000..2b6fc1122f --- /dev/null +++ b/include/media/v4l2-int-device.h @@ -0,0 +1,210 @@ +/* + * include/media/v4l2-int-device.h + * + * V4L2 internal ioctl interface. + * + * Copyright (C) 2007 Nokia Corporation. + * + * Contact: Sakari Ailus + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * 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., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#ifndef V4L2_INT_DEVICE_H +#define V4L2_INT_DEVICE_H + +#include +#include + +#define V4L2NAMESIZE 32 + +enum v4l2_int_type { + v4l2_int_type_master = 1, + v4l2_int_type_slave +}; + +enum v4l2_int_ioctl_num { + /* + * + * "Proper" V4L ioctls, as in struct video_device. + * + */ + vidioc_int_enum_fmt_cap_num = 1, + vidioc_int_g_fmt_cap_num, + vidioc_int_s_fmt_cap_num, + vidioc_int_try_fmt_cap_num, + vidioc_int_queryctrl_num, + vidioc_int_g_ctrl_num, + vidioc_int_s_ctrl_num, + vidioc_int_g_parm_num, + vidioc_int_s_parm_num, + + /* + * + * Strictly internal ioctls. + * + */ + /* Initialise the device when slave attaches to the master. */ + vidioc_int_dev_init_num = 1000, + /* Delinitialise the device at slave detach. */ + vidioc_int_dev_exit_num, + /* Set device power state: 0 is off, non-zero is on. */ + vidioc_int_s_power_num, + /* Get parallel interface clock speed for current settings. */ + vidioc_int_g_ext_clk_num, + /* + * Tell what the parallel interface clock speed actually is. + */ + vidioc_int_s_ext_clk_num, + /* Does the slave need to be reset after VIDIOC_DQBUF? */ + vidioc_int_g_needs_reset_num, + + /* + * + * VIDIOC_INT_* ioctls. + * + */ + /* VIDIOC_INT_RESET */ + vidioc_int_reset_num, + /* VIDIOC_INT_INIT */ + vidioc_int_init_num, + /* VIDIOC_INT_G_CHIP_IDENT */ + vidioc_int_g_chip_ident_num, + + /* + * + * Start of private ioctls. + * + */ + vidioc_int_priv_start_num = 2000, +}; + +struct v4l2_int_device; + +struct v4l2_int_master { + int (*attach)(struct v4l2_int_device *master, + struct v4l2_int_device *slave); + void (*detach)(struct v4l2_int_device *master); +}; + +typedef int (v4l2_int_ioctl_func)(struct v4l2_int_device *); +typedef int (v4l2_int_ioctl_func_0)(struct v4l2_int_device *); +typedef int (v4l2_int_ioctl_func_1)(struct v4l2_int_device *, void *); + +struct v4l2_int_ioctl_desc { + int num; + v4l2_int_ioctl_func *func; +}; + +struct v4l2_int_slave { + /* Don't touch master. */ + struct v4l2_int_device *master; + + char attach_to[V4L2NAMESIZE]; + + int num_ioctls; + struct v4l2_int_ioctl_desc *ioctls; +}; + +struct v4l2_int_device { + /* Don't touch head. */ + struct list_head head; + + struct module *module; + + char name[V4L2NAMESIZE]; + + enum v4l2_int_type type; + union { + struct v4l2_int_master *master; + struct v4l2_int_slave *slave; + } u; + + void *priv; +}; + +int v4l2_int_device_register(struct v4l2_int_device *d); +void v4l2_int_device_unregister(struct v4l2_int_device *d); + +int v4l2_int_ioctl_0(struct v4l2_int_device *d, int cmd); +int v4l2_int_ioctl_1(struct v4l2_int_device *d, int cmd, void *arg); + +/* + * + * IOCTL wrapper functions for better type checking. + * + */ + +#define V4L2_INT_WRAPPER_0(name) \ + static inline int vidioc_int_##name(struct v4l2_int_device *d) \ + { \ + return v4l2_int_ioctl_0(d, vidioc_int_##name##_num); \ + } \ + \ + static inline struct v4l2_int_ioctl_desc \ + vidioc_int_##name##_cb(int (*func) \ + (struct v4l2_int_device *)) \ + { \ + struct v4l2_int_ioctl_desc desc; \ + \ + desc.num = vidioc_int_##name##_num; \ + desc.func = (v4l2_int_ioctl_func *)func; \ + \ + return desc; \ + } + +#define V4L2_INT_WRAPPER_1(name, arg_type, asterisk) \ + static inline int vidioc_int_##name(struct v4l2_int_device *d, \ + arg_type asterisk arg) \ + { \ + return v4l2_int_ioctl_1(d, vidioc_int_##name##_num, \ + (void *)arg); \ + } \ + \ + static inline struct v4l2_int_ioctl_desc \ + vidioc_int_##name##_cb(int (*func) \ + (struct v4l2_int_device *, \ + arg_type asterisk)) \ + { \ + struct v4l2_int_ioctl_desc desc; \ + \ + desc.num = vidioc_int_##name##_num; \ + desc.func = (v4l2_int_ioctl_func *)func; \ + \ + return desc; \ + } + +V4L2_INT_WRAPPER_1(enum_fmt_cap, struct v4l2_fmtdesc, *); +V4L2_INT_WRAPPER_1(g_fmt_cap, struct v4l2_format, *); +V4L2_INT_WRAPPER_1(s_fmt_cap, struct v4l2_format, *); +V4L2_INT_WRAPPER_1(try_fmt_cap, struct v4l2_format, *); +V4L2_INT_WRAPPER_1(queryctrl, struct v4l2_queryctrl, *); +V4L2_INT_WRAPPER_1(g_ctrl, struct v4l2_control, *); +V4L2_INT_WRAPPER_1(s_ctrl, struct v4l2_control, *); +V4L2_INT_WRAPPER_1(g_parm, struct v4l2_streamparm, *); +V4L2_INT_WRAPPER_1(s_parm, struct v4l2_streamparm, *); + +V4L2_INT_WRAPPER_0(dev_init); +V4L2_INT_WRAPPER_0(dev_exit); +V4L2_INT_WRAPPER_1(s_power, int, ); +V4L2_INT_WRAPPER_1(s_ext_clk, u32, ); +V4L2_INT_WRAPPER_1(g_ext_clk, u32, *); +V4L2_INT_WRAPPER_1(g_needs_reset, void, *); + +V4L2_INT_WRAPPER_0(reset); +V4L2_INT_WRAPPER_0(init); +V4L2_INT_WRAPPER_1(g_chip_ident, int, *); + +#endif