Loading Documentation/video-output.txt 0 → 100644 +34 −0 Original line number Diff line number Diff line Video Output Switcher Control ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2006 luming.yu@intel.com The output sysfs class driver provides an abstract video output layer that can be used to hook platform specific methods to enable/disable video output device through common sysfs interface. For example, on my IBM ThinkPad T42 laptop, The ACPI video driver registered its output devices and read/write method for 'state' with output sysfs class. The user interface under sysfs is: linux:/sys/class/video_output # tree . . |-- CRT0 | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 | |-- state | |-- subsystem -> ../../../class/video_output | `-- uevent |-- DVI0 | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 | |-- state | |-- subsystem -> ../../../class/video_output | `-- uevent |-- LCD0 | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 | |-- state | |-- subsystem -> ../../../class/video_output | `-- uevent `-- TV0 |-- device -> ../../../devices/pci0000:00/0000:00:01.0 |-- state |-- subsystem -> ../../../class/video_output `-- uevent drivers/video/output.c 0 → 100644 +129 −0 Original line number Diff line number Diff line /* * output.c - Display Output Switch driver * * Copyright (C) 2006 Luming Yu <luming.yu@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * 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/module.h> #include <linux/video_output.h> #include <linux/err.h> #include <linux/ctype.h> MODULE_DESCRIPTION("Display Output Switcher Lowlevel Control Abstraction"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Luming Yu <luming.yu@intel.com>"); static ssize_t video_output_show_state(struct class_device *dev,char *buf) { ssize_t ret_size = 0; struct output_device *od = to_output_device(dev); if (od->props) ret_size = sprintf(buf,"%.8x\n",od->props->get_status(od)); return ret_size; } static ssize_t video_output_store_state(struct class_device *dev, const char *buf,size_t count) { char *endp; struct output_device *od = to_output_device(dev); int request_state = simple_strtoul(buf,&endp,0); size_t size = endp - buf; if (*endp && isspace(*endp)) size++; if (size != count) return -EINVAL; if (od->props) { od->request_state = request_state; od->props->set_state(od); } return count; } static void video_output_class_release(struct class_device *dev) { struct output_device *od = to_output_device(dev); kfree(od); } static struct class_device_attribute video_output_attributes[] = { __ATTR(state, 0644, video_output_show_state, video_output_store_state), __ATTR_NULL, }; static struct class video_output_class = { .name = "video_output", .release = video_output_class_release, .class_dev_attrs = video_output_attributes, }; struct output_device *video_output_register(const char *name, struct device *dev, void *devdata, struct output_properties *op) { struct output_device *new_dev; int ret_code = 0; new_dev = kzalloc(sizeof(struct output_device),GFP_KERNEL); if (!new_dev) { ret_code = -ENOMEM; goto error_return; } new_dev->props = op; new_dev->class_dev.class = &video_output_class; new_dev->class_dev.dev = dev; strlcpy(new_dev->class_dev.class_id,name,KOBJ_NAME_LEN); class_set_devdata(&new_dev->class_dev,devdata); ret_code = class_device_register(&new_dev->class_dev); if (ret_code) { kfree(new_dev); goto error_return; } return new_dev; error_return: return ERR_PTR(ret_code); } EXPORT_SYMBOL(video_output_register); void video_output_unregister(struct output_device *dev) { if (!dev) return; class_device_unregister(&dev->class_dev); } EXPORT_SYMBOL(video_output_unregister); static void __exit video_output_class_exit(void) { class_unregister(&video_output_class); } static int __init video_output_class_init(void) { return class_register(&video_output_class); } postcore_initcall(video_output_class_init); module_exit(video_output_class_exit); include/linux/video_output.h 0 → 100644 +42 −0 Original line number Diff line number Diff line /* * * Copyright (C) 2006 Luming Yu <luming.yu@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * 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 _LINUX_VIDEO_OUTPUT_H #define _LINUX_VIDEO_OUTPUT_H #include <linux/device.h> struct output_device; struct output_properties { int (*set_state)(struct output_device *); int (*get_status)(struct output_device *); }; struct output_device { int request_state; struct output_properties *props; struct class_device class_dev; }; #define to_output_device(obj) container_of(obj, struct output_device, class_dev) struct output_device *video_output_register(const char *name, struct device *dev, void *devdata, struct output_properties *op); void video_output_unregister(struct output_device *dev); #endif Loading
Documentation/video-output.txt 0 → 100644 +34 −0 Original line number Diff line number Diff line Video Output Switcher Control ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2006 luming.yu@intel.com The output sysfs class driver provides an abstract video output layer that can be used to hook platform specific methods to enable/disable video output device through common sysfs interface. For example, on my IBM ThinkPad T42 laptop, The ACPI video driver registered its output devices and read/write method for 'state' with output sysfs class. The user interface under sysfs is: linux:/sys/class/video_output # tree . . |-- CRT0 | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 | |-- state | |-- subsystem -> ../../../class/video_output | `-- uevent |-- DVI0 | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 | |-- state | |-- subsystem -> ../../../class/video_output | `-- uevent |-- LCD0 | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 | |-- state | |-- subsystem -> ../../../class/video_output | `-- uevent `-- TV0 |-- device -> ../../../devices/pci0000:00/0000:00:01.0 |-- state |-- subsystem -> ../../../class/video_output `-- uevent
drivers/video/output.c 0 → 100644 +129 −0 Original line number Diff line number Diff line /* * output.c - Display Output Switch driver * * Copyright (C) 2006 Luming Yu <luming.yu@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * 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/module.h> #include <linux/video_output.h> #include <linux/err.h> #include <linux/ctype.h> MODULE_DESCRIPTION("Display Output Switcher Lowlevel Control Abstraction"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Luming Yu <luming.yu@intel.com>"); static ssize_t video_output_show_state(struct class_device *dev,char *buf) { ssize_t ret_size = 0; struct output_device *od = to_output_device(dev); if (od->props) ret_size = sprintf(buf,"%.8x\n",od->props->get_status(od)); return ret_size; } static ssize_t video_output_store_state(struct class_device *dev, const char *buf,size_t count) { char *endp; struct output_device *od = to_output_device(dev); int request_state = simple_strtoul(buf,&endp,0); size_t size = endp - buf; if (*endp && isspace(*endp)) size++; if (size != count) return -EINVAL; if (od->props) { od->request_state = request_state; od->props->set_state(od); } return count; } static void video_output_class_release(struct class_device *dev) { struct output_device *od = to_output_device(dev); kfree(od); } static struct class_device_attribute video_output_attributes[] = { __ATTR(state, 0644, video_output_show_state, video_output_store_state), __ATTR_NULL, }; static struct class video_output_class = { .name = "video_output", .release = video_output_class_release, .class_dev_attrs = video_output_attributes, }; struct output_device *video_output_register(const char *name, struct device *dev, void *devdata, struct output_properties *op) { struct output_device *new_dev; int ret_code = 0; new_dev = kzalloc(sizeof(struct output_device),GFP_KERNEL); if (!new_dev) { ret_code = -ENOMEM; goto error_return; } new_dev->props = op; new_dev->class_dev.class = &video_output_class; new_dev->class_dev.dev = dev; strlcpy(new_dev->class_dev.class_id,name,KOBJ_NAME_LEN); class_set_devdata(&new_dev->class_dev,devdata); ret_code = class_device_register(&new_dev->class_dev); if (ret_code) { kfree(new_dev); goto error_return; } return new_dev; error_return: return ERR_PTR(ret_code); } EXPORT_SYMBOL(video_output_register); void video_output_unregister(struct output_device *dev) { if (!dev) return; class_device_unregister(&dev->class_dev); } EXPORT_SYMBOL(video_output_unregister); static void __exit video_output_class_exit(void) { class_unregister(&video_output_class); } static int __init video_output_class_init(void) { return class_register(&video_output_class); } postcore_initcall(video_output_class_init); module_exit(video_output_class_exit);
include/linux/video_output.h 0 → 100644 +42 −0 Original line number Diff line number Diff line /* * * Copyright (C) 2006 Luming Yu <luming.yu@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * 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 _LINUX_VIDEO_OUTPUT_H #define _LINUX_VIDEO_OUTPUT_H #include <linux/device.h> struct output_device; struct output_properties { int (*set_state)(struct output_device *); int (*get_status)(struct output_device *); }; struct output_device { int request_state; struct output_properties *props; struct class_device class_dev; }; #define to_output_device(obj) container_of(obj, struct output_device, class_dev) struct output_device *video_output_register(const char *name, struct device *dev, void *devdata, struct output_properties *op); void video_output_unregister(struct output_device *dev); #endif
