Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
Hi,
I missed the CONFIG_LEDS_CLASS_MODULE configuration option in the previous
version of this patch, now it is added.
Regards,
Márton Németh
---
From: Márton Németh nm...@freemail.hu
On Labtec Webcam 2200 there is a feedback LED which can be controlled
independent from the streaming. The feedback LED can be used from
user space application to show for example detected motion or to
distinguish between the preview and on-air state of the video stream.
The default value of the LED trigger keeps the previous behaviour:
LED is off when the stream is off, LED is on if the stream is on.
The code is working in the following three cases:
(1) when the LED subsystem ins not configured at all;
(2) when the LED subsystem is available, but the LED triggers are not
available and
(3) when both the LED subsystem and LED triggers are configured.
Signed-off-by: Márton Németh nm...@freemail.hu
---
diff -r d8fafa7d88dc linux/drivers/media/video/gspca/pac7302.c
--- a/linux/drivers/media/video/gspca/pac7302.c Thu Feb 18 19:02:51 2010 +0100
+++ b/linux/drivers/media/video/gspca/pac7302.c Sat Feb 27 09:10:44 2010 +0100
@@ -6,6 +6,7 @@
*
* Separated from Pixart PAC7311 library by Márton Németh
* Camera button input handling by Márton Németh nm...@freemail.hu
+ * LED control by Márton Németh nm...@freemail.hu
* Copyright (C) 2009-2010 Márton Németh nm...@freemail.hu
*
* This program is free software; you can redistribute it and/or modify
@@ -62,6 +63,7 @@
0 | 0xc6 | setwhitebalance()
0 | 0xc7 | setbluebalance()
0 | 0xdc | setbrightcont(), setcolors()
+1 | 0x78 | set_streaming_led()
3 | 0x02 | setexposure()
3 | 0x10 | setgain()
3 | 0x11 | setcolors(), setgain(), setexposure(), sethvflip()
@@ -72,6 +74,8 @@
#include linux/input.h
#include media/v4l2-chip-ident.h
+#include linux/leds.h
+#include linux/workqueue.h
#include gspca.h
MODULE_AUTHOR(Thomas Kaiser tho...@kaiser-linux.li);
@@ -91,6 +95,7 @@
unsigned char gain;
unsigned char exposure;
unsigned char autogain;
+ unsigned char led;
__u8 hflip;
__u8 vflip;
u8 flags;
@@ -101,6 +106,16 @@
u8 autogain_ignore_frames;
atomic_t avg_lum;
+
+#if defined(CONFIG_LEDS_CLASS) || defined(CONFIG_LEDS_CLASS_MODULE)
+ struct led_classdev led_cdev;
+ struct work_struct led_work;
+ char name[32];
+#ifdef CONFIG_LEDS_TRIGGERS
+ struct led_trigger led_trigger;
+ char trigger_name[32];
+#endif
+#endif
};
/* V4L2 controls supported by the driver */
@@ -572,6 +587,7 @@
sd-gain = GAIN_DEF;
sd-exposure = EXPOSURE_DEF;
sd-autogain = AUTOGAIN_DEF;
+ sd-led = 0;
sd-hflip = HFLIP_DEF;
sd-vflip = VFLIP_DEF;
sd-flags = id-driver_info;
@@ -716,6 +732,58 @@
reg_w(gspca_dev, 0x11, 0x01);
}
+static void set_streaming_led(struct gspca_dev *gspca_dev, u8 streaming)
+{
+ struct sd *sd = (struct sd *) gspca_dev;
+ u8 data = 0;
+
+ if (sd-led) {
+ if (streaming)
+ data = 0x01;
+ else
+ data = 0x00;
+ } else {
+ if (streaming)
+ data = 0x41;
+ else
+ data = 0x40;
+ }
+
+ reg_w(gspca_dev, 0xff, 0x01);
+ reg_w(gspca_dev, 0x78, data);
+}
+
+#if defined(CONFIG_LEDS_CLASS) || defined(CONFIG_LEDS_CLASS_MODULE)
+/* Set the LED, may sleep */
+static void led_work(struct work_struct *work)
+{
+ struct sd *sd = container_of(work, struct sd, led_work);
+ struct gspca_dev *gspca_dev = sd-gspca_dev;
+
+ mutex_lock(gspca_dev-usb_lock);
+ set_streaming_led(gspca_dev, gspca_dev-streaming);
+ mutex_unlock(gspca_dev-usb_lock);
+}
+
+/* LED state set request, must not sleep */
+static void led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ u8 new_value;
+ struct sd *sd = container_of(led_cdev, struct sd, led_cdev);
+
+ if (value == LED_OFF)
+ new_value = 0;
+ else
+ new_value = 1;
+
+ if (sd-led != new_value) {
+ sd-led = new_value;
+ schedule_work(sd-led_work);
+ }
+}
+#endif
+
/* this function is called at probe and resume time for pac7302 */
static int sd_init(struct gspca_dev *gspca_dev)
{
@@ -747,27 +815,60 @@
atomic_set(sd-avg_lum, -1);
/* start stream */
- reg_w(gspca_dev, 0xff, 0x01);
- reg_w(gspca_dev, 0x78, 0x01);
+
+#if (defined(CONFIG_LEDS_CLASS) || defined(CONFIG_LEDS_CLASS_MODULE))
defined(CONFIG_LEDS_TRIGGERS)
+ led_trigger_event(sd-led_trigger, LED_FULL);
+#elif defined(CONFIG_LEDS_CLASS) || defined(CONFIG_LEDS_CLASS_MODULE)
+ sd-led_cdev.brightness = sd-led_cdev.max_brightness;
+ if (!(sd-led_cdev.flags LED_SUSPENDED))
+
Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
Hi, Hans de Goede wrote: Hi, On 02/27/2010 01:20 AM, Németh Márton wrote: From: Márton Némethnm...@freemail.hu On Labtec Webcam 2200 there is a feedback LED which can be controlled independent from the streaming. This is true for a lot of cameras, so if we are going to add a way to support control of the LED separate of the streaming state, we should do that at the gspca_main level, and let sub drivers which support this export a set_led callback function. If the code is moved to gspca_main level, what shall be the name of the LED? According to Documentation/leds-class.txt, chapter LED Device Naming my proposal for devicename would be: * /sys/class/leds/video-0::camera * /sys/class/leds/video-1::camera * /sys/class/leds/video-2::camera * ... or * /sys/class/leds/video0::camera * /sys/class/leds/video1::camera * /sys/class/leds/video2::camera * ... Which is the right one? I must say I personally don't see much of a use case for this feature, but I believe JF Moine does, so I'll leave further comments and review of this to JF. I do believe it is important that if we go this way we do so add the gspca_main level. Regards, Hans -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
On Sat, 27 Feb 2010 08:53:16 +0100 Hans de Goede hdego...@redhat.com wrote: This is true for a lot of cameras, so if we are going to add a way to support control of the LED separate of the streaming state, we should do that at the gspca_main level, and let sub drivers which support this export a set_led callback function. I must say I personally don't see much of a use case for this feature, but I believe JF Moine does, so I'll leave further comments and review of this to JF. I do believe it is important that if we go this way we do so add the gspca_main level. Hi, I don't like this mechanism to switch on or off the webcam LEDs. Here are some arguments (some of them were sent last year to the list): 1) End users. Many Linux users don't know the kernel internals, nor which of the too many applications they should use to make their devices work. Actually, there are a few X11 programs in common Linux distros which can handle the webcam parameters: I just know about vlc and v4l2ucp, and they don't even handle the VIDIOC_G_JPEGCOMP and VIDIOC_S_JPEGCOMP ioctls which are part of the v4l2 API. The LED interface uses the /sys file system. Will the webcam programs offer access to this interface? I don't believe it. So, the users will have to search how they can switch on or off the LEDs of their webcams, and then, when found, they should start a X terminal and run a command to do the job! On the other hand, a webcam LED control, whether general or private, is available in the graphical interface as soon as the driver offers it. 2) Memory overhead. Using the led class adds more kernel code and asks the webcam drivers to create a new device. Also, the function called for changing the LED brighness cannot sleep, so the use a workqueue is required. On contrary, with a webcam control, only one byte (for 8 LEDs) is added to the webcam structure and the change is immediatly done in the ioctl. 3) Development. If nobody wants a LED control in the v4l2 interface, I think the code added to access the led class could be splitted between the different subsystem. For example, the workqueue handling could be done in the led class itself... Cheers. -- Ken ar c'hentañ | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/ -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
Hi, Jean-Francois Moine wrote: On Sat, 27 Feb 2010 08:53:16 +0100 Hans de Goede hdego...@redhat.com wrote: This is true for a lot of cameras, so if we are going to add a way to support control of the LED separate of the streaming state, we should do that at the gspca_main level, and let sub drivers which support this export a set_led callback function. I must say I personally don't see much of a use case for this feature, but I believe JF Moine does, so I'll leave further comments and review of this to JF. I do believe it is important that if we go this way we do so add the gspca_main level. Hi, I don't like this mechanism to switch on or off the webcam LEDs. Here are some arguments (some of them were sent last year to the list): I could accept both the V4L2 control solution or the LED subclass solution for handling the camera LED. I miss a little the positive side of using the LED subclass from the list, so I try take the role of that side and add them. 1) End users. Many Linux users don't know the kernel internals, nor which of the too many applications they should use to make their devices work. Actually, there are a few X11 programs in common Linux distros which can handle the webcam parameters: I just know about vlc and v4l2ucp, and they don't even handle the VIDIOC_G_JPEGCOMP and VIDIOC_S_JPEGCOMP ioctls which are part of the v4l2 API. The LED interface uses the /sys file system. Will the webcam programs offer access to this interface? I don't believe it. So, the users will have to search how they can switch on or off the LEDs of their webcams, and then, when found, they should start a X terminal and run a command to do the job! The programs like v4l2ucp can be extended to handle the /sys/class/leds interface. This is work but the user will not recognise the difference as long as the GUI supports it. On the other hand, a webcam LED control, whether general or private, is available in the graphical interface as soon as the driver offers it. 2) Memory overhead. Using the led class adds more kernel code and asks the webcam drivers to create a new device. Also, the function called for changing the LED brighness cannot sleep, so the use a workqueue is required. Let me show the numbers on a 32bit machine: sizeof(struct gspca_dev) = 2032 bytes sizeof(struct led_classdev) = 112 bytes sizeof(struct work_struct) = 28 bytes sizeof(struct led_trigger) = 52 bytes Additionally two strings are also needed one for the LED device name and one for the LED trigger. Let's take 32 bytes for each (this value can be made smaller). This means that the necessary memory is 112+28+52+2*32 = 256 bytes. The pac7302 driver subdriver structure with LED device, workqueue and LED trigger is: sizeof(struct sd) = 2308 bytes So the memory usage increase is 1-2308/2032 = 13.6%. I would compare the structure size with the memory page size of the x86 system which is 4096 bytes (see the return value of getpagesize(2)). On contrary, with a webcam control, only one byte (for 8 LEDs) is added to the webcam structure and the change is immediatly done in the ioctl. 3) Development. If nobody wants a LED control in the v4l2 interface, I think the code added to access the led class could be splitted between the different subsystem. For example, the workqueue handling could be done in the led class itself... Advantages of LED subsystem are: 4) Flexible usage of the camera LED for purposes unrelated to camera or unusual way, e.g. just blinking the LED with ledtrig-timer. 5) The status of the LED can be read back by reading /sys/class/leds/video0::camera/brightness. This is not possible when the auto menu item is selected from a V4L2 based menu control. Regards, Márton Németh -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
Hi, On 02/27/2010 04:35 PM, Németh Márton wrote: Hi, Jean-Francois Moine wrote: On Sat, 27 Feb 2010 08:53:16 +0100 Hans de Goedehdego...@redhat.com wrote: This is true for a lot of cameras, so if we are going to add a way to support control of the LED separate of the streaming state, we should do that at the gspca_main level, and let sub drivers which support this export a set_led callback function. I must say I personally don't see much of a use case for this feature, but I believe JF Moine does, so I'll leave further comments and review of this to JF. I do believe it is important that if we go this way we do so add the gspca_main level. Hi, I don't like this mechanism to switch on or off the webcam LEDs. Here are some arguments (some of them were sent last year to the list): I could accept both the V4L2 control solution or the LED subclass solution for handling the camera LED. I miss a little the positive side of using the LED subclass from the list, so I try take the role of that side and add them. I have to side with JF here, I see very little use in the led class interface for webcams. Another important reason to choose for a simple v4l2 menu control solution here is consistency certain logitech uvc cameras already offer Led control through a vendor extension control unit, which (when using uvcdynctrl to enable vendor extension control units), currently shows up as a v4l2 control. So for consistency with existing practices a v4l2 control seems better suited. Also I must say that the led class seems overkill. I would like to note that even if we go the v4l2 control way it still makes sense to handle this in gspca_main, rather then implementing it separately in every sub driver. 1) End users. Many Linux users don't know the kernel internals, nor which of the too many applications they should use to make their devices work. Actually, there are a few X11 programs in common Linux distros which can handle the webcam parameters: I just know about vlc and v4l2ucp, and they don't even handle the VIDIOC_G_JPEGCOMP and VIDIOC_S_JPEGCOMP ioctls which are part of the v4l2 API. The LED interface uses the /sys file system. Will the webcam programs offer access to this interface? I don't believe it. So, the users will have to search how they can switch on or off the LEDs of their webcams, and then, when found, they should start a X terminal and run a command to do the job! The programs like v4l2ucp can be extended to handle the /sys/class/leds interface. This is work but the user will not recognise the difference as long as the GUI supports it. Erm, no currently almost no v4l programs uses v4l2 controls properly, and I certainly see none supporting the led sysfs interface. I say this as someone who has done actual development on v4l2ucp, and who is currnetly involved in writing a GTK v4l2 control panel application. Regards, Hans -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
On Sat, 27 Feb 2010 20:12:05 +0100 Hans de Goede hdego...@redhat.com wrote: [snip] I would like to note that even if we go the v4l2 control way it still makes sense to handle this in gspca_main, rather then implementing it separately in every sub driver. There is nothing to do in the gspca_main: the control just does a usb_control write. I say this as someone ... who is currnetly involved in writing a GTK v4l2 control panel application. Great! -- Ken ar c'hentañ | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/ -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH 1/2] gspca pac7302: allow controlling LED separately
From: Márton Németh nm...@freemail.hu
On Labtec Webcam 2200 there is a feedback LED which can be controlled
independent from the streaming. The feedback LED can be used from
user space application to show for example detected motion or to
distinguish between the preview and on-air state of the video stream.
The default value of the LED trigger keeps the previous behaviour:
LED is off when the stream is off, LED is on if the stream is on.
The code is working in the following three cases:
(1) when the LED subsystem ins not configured at all;
(2) when the LED subsystem is available, but the LED triggers are not
available and
(3) when both the LED subsystem and LED triggers are configured.
Signed-off-by: Márton Németh nm...@freemail.hu
---
diff -r 4f102b2f7ac1 linux/drivers/media/video/gspca/pac7302.c
--- a/linux/drivers/media/video/gspca/pac7302.c Thu Jan 28 20:35:40 2010 +0100
+++ b/linux/drivers/media/video/gspca/pac7302.c Sat Feb 27 00:57:32 2010 +0100
@@ -6,6 +6,7 @@
*
* Separated from Pixart PAC7311 library by Márton Németh
* Camera button input handling by Márton Németh nm...@freemail.hu
+ * LED control by Márton Németh nm...@freemail.hu
* Copyright (C) 2009-2010 Márton Németh nm...@freemail.hu
*
* This program is free software; you can redistribute it and/or modify
@@ -62,6 +63,7 @@
0 | 0xc6 | setwhitebalance()
0 | 0xc7 | setbluebalance()
0 | 0xdc | setbrightcont(), setcolors()
+1 | 0x78 | set_streaming_led()
3 | 0x02 | setexposure()
3 | 0x10 | setgain()
3 | 0x11 | setcolors(), setgain(), setexposure(), sethvflip()
@@ -72,6 +74,8 @@
#include linux/input.h
#include media/v4l2-chip-ident.h
+#include linux/leds.h
+#include linux/workqueue.h
#include gspca.h
MODULE_AUTHOR(Thomas Kaiser tho...@kaiser-linux.li);
@@ -91,6 +95,7 @@
unsigned char gain;
unsigned char exposure;
unsigned char autogain;
+ unsigned char led;
__u8 hflip;
__u8 vflip;
u8 flags;
@@ -101,6 +106,16 @@
u8 autogain_ignore_frames;
atomic_t avg_lum;
+
+#ifdef CONFIG_LEDS_CLASS
+ struct led_classdev led_cdev;
+ struct work_struct led_work;
+ char name[32];
+#ifdef CONFIG_LEDS_TRIGGERS
+ struct led_trigger led_trigger;
+ char trigger_name[32];
+#endif
+#endif
};
/* V4L2 controls supported by the driver */
@@ -572,6 +587,7 @@
sd-gain = GAIN_DEF;
sd-exposure = EXPOSURE_DEF;
sd-autogain = AUTOGAIN_DEF;
+ sd-led = 0;
sd-hflip = HFLIP_DEF;
sd-vflip = VFLIP_DEF;
sd-flags = id-driver_info;
@@ -716,6 +732,58 @@
reg_w(gspca_dev, 0x11, 0x01);
}
+static void set_streaming_led(struct gspca_dev *gspca_dev, u8 streaming)
+{
+ struct sd *sd = (struct sd *) gspca_dev;
+ u8 data = 0;
+
+ if (sd-led) {
+ if (streaming)
+ data = 0x01;
+ else
+ data = 0x00;
+ } else {
+ if (streaming)
+ data = 0x41;
+ else
+ data = 0x40;
+ }
+
+ reg_w(gspca_dev, 0xff, 0x01);
+ reg_w(gspca_dev, 0x78, data);
+}
+
+#ifdef CONFIG_LEDS_CLASS
+/* Set the LED, may sleep */
+static void led_work(struct work_struct *work)
+{
+ struct sd *sd = container_of(work, struct sd, led_work);
+ struct gspca_dev *gspca_dev = sd-gspca_dev;
+
+ mutex_lock(gspca_dev-usb_lock);
+ set_streaming_led(gspca_dev, gspca_dev-streaming);
+ mutex_unlock(gspca_dev-usb_lock);
+}
+
+/* LED state set request, must not sleep */
+static void led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ u8 new_value;
+ struct sd *sd = container_of(led_cdev, struct sd, led_cdev);
+
+ if (value == LED_OFF)
+ new_value = 0;
+ else
+ new_value = 1;
+
+ if (sd-led != new_value) {
+ sd-led = new_value;
+ schedule_work(sd-led_work);
+ }
+}
+#endif
+
/* this function is called at probe and resume time for pac7302 */
static int sd_init(struct gspca_dev *gspca_dev)
{
@@ -747,27 +815,60 @@
atomic_set(sd-avg_lum, -1);
/* start stream */
- reg_w(gspca_dev, 0xff, 0x01);
- reg_w(gspca_dev, 0x78, 0x01);
+
+#if defined(CONFIG_LEDS_CLASS) defined(CONFIG_LEDS_TRIGGERS)
+ led_trigger_event(sd-led_trigger, LED_FULL);
+#elif defined(CONFIG_LEDS_CLASS)
+ sd-led_cdev.brightness = sd-led_cdev.max_brightness;
+ if (!(sd-led_cdev.flags LED_SUSPENDED))
+ sd-led_cdev.brightness_set(sd-led_cdev,
+ sd-led_cdev.brightness);
+#else
+ sd-led = 1;
+#endif
+ set_streaming_led(gspca_dev, 1);
return gspca_dev-usb_err;
}
static void sd_stopN(struct gspca_dev *gspca_dev)
{
+ struct sd *sd = container_of(gspca_dev, struct sd,
Re: [PATCH 1/2] gspca pac7302: allow controlling LED separately
Hi, On 02/27/2010 01:20 AM, Németh Márton wrote: From: Márton Némethnm...@freemail.hu On Labtec Webcam 2200 there is a feedback LED which can be controlled independent from the streaming. This is true for a lot of cameras, so if we are going to add a way to support control of the LED separate of the streaming state, we should do that at the gspca_main level, and let sub drivers which support this export a set_led callback function. I must say I personally don't see much of a use case for this feature, but I believe JF Moine does, so I'll leave further comments and review of this to JF. I do believe it is important that if we go this way we do so add the gspca_main level. Regards, Hans -- To unsubscribe from this list: send the line unsubscribe linux-media in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
