From 2dec3ba8d872aa3ffbcdb8f6f8a2c0bcd44e9910 Mon Sep 17 00:00:00 2001 From: Yu Luming Date: Tue, 19 Dec 2006 12:56:17 -0800 Subject: output: Add display output class support Add generic abstract layer for display output switch control. 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. Signed-off-by: Luming Yu Cc: "Antonino A. Daplas" Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- drivers/video/output.c | 129 +++++++++++++++++++++++++++++++++++++++++++ include/linux/video_output.h | 42 ++++++++++++++ 2 files changed, 171 insertions(+) create mode 100644 drivers/video/output.c create mode 100644 include/linux/video_output.h diff --git a/drivers/video/output.c b/drivers/video/output.c new file mode 100644 index 0000000..1473f2c --- /dev/null +++ b/drivers/video/output.c @@ -0,0 +1,129 @@ +/* + * output.c - Display Output Switch driver + * + * Copyright (C) 2006 Luming Yu + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * 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 +#include +#include +#include + + +MODULE_DESCRIPTION("Display Output Switcher Lowlevel Control Abstraction"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Luming Yu "); + +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); diff --git a/include/linux/video_output.h b/include/linux/video_output.h new file mode 100644 index 0000000..e63e0c0 --- /dev/null +++ b/include/linux/video_output.h @@ -0,0 +1,42 @@ +/* + * + * Copyright (C) 2006 Luming Yu + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * 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 +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 -- cgit v1.1 From b03637b8863159a4518cb0a9ab90577460fe3417 Mon Sep 17 00:00:00 2001 From: Yu Luming Date: Tue, 19 Dec 2006 12:56:18 -0800 Subject: output: Add output class document Signed-off-by: Luming Yu Cc: "Antonino A. Daplas" Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- Documentation/video-output.txt | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 Documentation/video-output.txt diff --git a/Documentation/video-output.txt b/Documentation/video-output.txt new file mode 100644 index 0000000..e517011 --- /dev/null +++ b/Documentation/video-output.txt @@ -0,0 +1,34 @@ + + 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 + -- cgit v1.1