diff options
Diffstat (limited to 'Documentation')
33 files changed, 1085 insertions, 181 deletions
diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index 6434f0df012e..6cd6daefaaed 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -20,7 +20,7 @@ Description: lsm: [[subj_user=] [subj_role=] [subj_type=] [obj_user=] [obj_role=] [obj_type=]] - base: func:= [BPRM_CHECK][FILE_MMAP][INODE_PERMISSION] + base: func:= [BPRM_CHECK][FILE_MMAP][FILE_CHECK] mask:= [MAY_READ] [MAY_WRITE] [MAY_APPEND] [MAY_EXEC] fsmagic:= hex value uid:= decimal value @@ -40,11 +40,11 @@ Description: measure func=BPRM_CHECK measure func=FILE_MMAP mask=MAY_EXEC - measure func=INODE_PERM mask=MAY_READ uid=0 + measure func=FILE_CHECK mask=MAY_READ uid=0 The default policy measures all executables in bprm_check, all files mmapped executable in file_mmap, and all files - open for read by root in inode_permission. + open for read by root in do_filp_open. Examples of LSM specific definitions: @@ -54,8 +54,8 @@ Description: dont_measure obj_type=var_log_t dont_measure obj_type=auditd_log_t - measure subj_user=system_u func=INODE_PERM mask=MAY_READ - measure subj_role=system_r func=INODE_PERM mask=MAY_READ + measure subj_user=system_u func=FILE_CHECK mask=MAY_READ + measure subj_role=system_r func=FILE_CHECK mask=MAY_READ Smack: - measure subj_user=_ func=INODE_PERM mask=MAY_READ + measure subj_user=_ func=FILE_CHECK mask=MAY_READ diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power new file mode 100644 index 000000000000..6123c523bfd7 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-power @@ -0,0 +1,79 @@ +What: /sys/devices/.../power/ +Date: January 2009 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/devices/.../power directory contains attributes + allowing the user space to check and modify some power + management related properties of given device. + +What: /sys/devices/.../power/wakeup +Date: January 2009 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/devices/.../power/wakeup attribute allows the user + space to check if the device is enabled to wake up the system + from sleep states, such as the memory sleep state (suspend to + RAM) and hibernation (suspend to disk), and to enable or disable + it to do that as desired. + + Some devices support "wakeup" events, which are hardware signals + used to activate the system from a sleep state. Such devices + have one of the following two values for the sysfs power/wakeup + file: + + + "enabled\n" to issue the events; + + "disabled\n" not to do so; + + In that cases the user space can change the setting represented + by the contents of this file by writing either "enabled", or + "disabled" to it. + + For the devices that are not capable of generating system wakeup + events this file contains "\n". In that cases the user space + cannot modify the contents of this file and the device cannot be + enabled to wake up the system. + +What: /sys/devices/.../power/control +Date: January 2009 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/devices/.../power/control attribute allows the user + space to control the run-time power management of the device. + + All devices have one of the following two values for the + power/control file: + + + "auto\n" to allow the device to be power managed at run time; + + "on\n" to prevent the device from being power managed; + + The default for all devices is "auto", which means that they may + be subject to automatic power management, depending on their + drivers. Changing this attribute to "on" prevents the driver + from power managing the device at run time. Doing that while + the device is suspended causes it to be woken up. + +What: /sys/devices/.../power/async +Date: January 2009 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/devices/.../async attribute allows the user space to + enable or diasble the device's suspend and resume callbacks to + be executed asynchronously (ie. in separate threads, in parallel + with the main suspend/resume thread) during system-wide power + transitions (eg. suspend to RAM, hibernation). + + All devices have one of the following two values for the + power/async file: + + + "enabled\n" to permit the asynchronous suspend/resume; + + "disabled\n" to forbid it; + + The value of this attribute may be changed by writing either + "enabled", or "disabled" to it. + + It generally is unsafe to permit the asynchronous suspend/resume + of a device unless it is certain that all of the PM dependencies + of the device are known to the PM core. However, for some + devices this attribute is set to "enabled" by bus type code or + device drivers and in that cases it should be safe to leave the + default value. diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index dcff4d0623ad..d6a801f45b48 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -101,3 +101,16 @@ Description: CAUTION: Using it will cause your machine's real-time (CMOS) clock to be set to a random invalid time after a resume. + +What: /sys/power/pm_async +Date: January 2009 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/pm_async file controls the switch allowing the + user space to enable or disable asynchronous suspend and resume + of devices. If enabled, this feature will cause some device + drivers' suspend and resume callbacks to be executed in parallel + with each other and with the main suspend thread. It is enabled + if this file contains "1", which is the default. It may be + disabled by writing "0" to this file, in which case all devices + will be suspended and resumed synchronously. diff --git a/Documentation/DocBook/v4l/io.xml b/Documentation/DocBook/v4l/io.xml index f92f24323b2a..e870330cbf77 100644 --- a/Documentation/DocBook/v4l/io.xml +++ b/Documentation/DocBook/v4l/io.xml @@ -589,7 +589,8 @@ number of a video input as in &v4l2-input; field <entry></entry> <entry>A place holder for future extensions and custom (driver defined) buffer types -<constant>V4L2_BUF_TYPE_PRIVATE</constant> and higher.</entry> +<constant>V4L2_BUF_TYPE_PRIVATE</constant> and higher. Applications +should set this to 0.</entry> </row> </tbody> </tgroup> diff --git a/Documentation/DocBook/v4l/vidioc-qbuf.xml b/Documentation/DocBook/v4l/vidioc-qbuf.xml index 187081778154..b843bd7b3897 100644 --- a/Documentation/DocBook/v4l/vidioc-qbuf.xml +++ b/Documentation/DocBook/v4l/vidioc-qbuf.xml @@ -54,12 +54,10 @@ to enqueue an empty (capturing) or filled (output) buffer in the driver's incoming queue. The semantics depend on the selected I/O method.</para> - <para>To enqueue a <link linkend="mmap">memory mapped</link> -buffer applications set the <structfield>type</structfield> field of a -&v4l2-buffer; to the same buffer type as previously &v4l2-format; -<structfield>type</structfield> and &v4l2-requestbuffers; -<structfield>type</structfield>, the <structfield>memory</structfield> -field to <constant>V4L2_MEMORY_MMAP</constant> and the + <para>To enqueue a buffer applications set the <structfield>type</structfield> +field of a &v4l2-buffer; to the same buffer type as was previously used +with &v4l2-format; <structfield>type</structfield> and &v4l2-requestbuffers; +<structfield>type</structfield>. Applications must also set the <structfield>index</structfield> field. Valid index numbers range from zero to the number of buffers allocated with &VIDIOC-REQBUFS; (&v4l2-requestbuffers; <structfield>count</structfield>) minus one. The @@ -70,8 +68,19 @@ intended for output (<structfield>type</structfield> is <constant>V4L2_BUF_TYPE_VBI_OUTPUT</constant>) applications must also initialize the <structfield>bytesused</structfield>, <structfield>field</structfield> and -<structfield>timestamp</structfield> fields. See <xref - linkend="buffer" /> for details. When +<structfield>timestamp</structfield> fields, see <xref +linkend="buffer" /> for details. +Applications must also set <structfield>flags</structfield> to 0. If a driver +supports capturing from specific video inputs and you want to specify a video +input, then <structfield>flags</structfield> should be set to +<constant>V4L2_BUF_FLAG_INPUT</constant> and the field +<structfield>input</structfield> must be initialized to the desired input. +The <structfield>reserved</structfield> field must be set to 0. +</para> + + <para>To enqueue a <link linkend="mmap">memory mapped</link> +buffer applications set the <structfield>memory</structfield> +field to <constant>V4L2_MEMORY_MMAP</constant>. When <constant>VIDIOC_QBUF</constant> is called with a pointer to this structure the driver sets the <constant>V4L2_BUF_FLAG_MAPPED</constant> and @@ -81,14 +90,10 @@ structure the driver sets the &EINVAL;.</para> <para>To enqueue a <link linkend="userp">user pointer</link> -buffer applications set the <structfield>type</structfield> field of a -&v4l2-buffer; to the same buffer type as previously &v4l2-format; -<structfield>type</structfield> and &v4l2-requestbuffers; -<structfield>type</structfield>, the <structfield>memory</structfield> -field to <constant>V4L2_MEMORY_USERPTR</constant> and the +buffer applications set the <structfield>memory</structfield> +field to <constant>V4L2_MEMORY_USERPTR</constant>, the <structfield>m.userptr</structfield> field to the address of the -buffer and <structfield>length</structfield> to its size. When the -buffer is intended for output additional fields must be set as above. +buffer and <structfield>length</structfield> to its size. When <constant>VIDIOC_QBUF</constant> is called with a pointer to this structure the driver sets the <constant>V4L2_BUF_FLAG_QUEUED</constant> flag and clears the <constant>V4L2_BUF_FLAG_MAPPED</constant> and @@ -96,13 +101,14 @@ flag and clears the <constant>V4L2_BUF_FLAG_MAPPED</constant> and <structfield>flags</structfield> field, or it returns an error code. This ioctl locks the memory pages of the buffer in physical memory, they cannot be swapped out to disk. Buffers remain locked until -dequeued, until the &VIDIOC-STREAMOFF; or &VIDIOC-REQBUFS; ioctl are +dequeued, until the &VIDIOC-STREAMOFF; or &VIDIOC-REQBUFS; ioctl is called, or until the device is closed.</para> <para>Applications call the <constant>VIDIOC_DQBUF</constant> ioctl to dequeue a filled (capturing) or displayed (output) buffer from the driver's outgoing queue. They just set the -<structfield>type</structfield> and <structfield>memory</structfield> +<structfield>type</structfield>, <structfield>memory</structfield> +and <structfield>reserved</structfield> fields of a &v4l2-buffer; as above, when <constant>VIDIOC_DQBUF</constant> is called with a pointer to this structure the driver fills the remaining fields or returns an error code.</para> diff --git a/Documentation/DocBook/v4l/vidioc-querybuf.xml b/Documentation/DocBook/v4l/vidioc-querybuf.xml index d834993e6191..e649805a4908 100644 --- a/Documentation/DocBook/v4l/vidioc-querybuf.xml +++ b/Documentation/DocBook/v4l/vidioc-querybuf.xml @@ -54,12 +54,13 @@ buffer at any time after buffers have been allocated with the &VIDIOC-REQBUFS; ioctl.</para> <para>Applications set the <structfield>type</structfield> field - of a &v4l2-buffer; to the same buffer type as previously + of a &v4l2-buffer; to the same buffer type as was previously used with &v4l2-format; <structfield>type</structfield> and &v4l2-requestbuffers; <structfield>type</structfield>, and the <structfield>index</structfield> field. Valid index numbers range from zero to the number of buffers allocated with &VIDIOC-REQBUFS; (&v4l2-requestbuffers; <structfield>count</structfield>) minus one. +The <structfield>reserved</structfield> field should to set to 0. After calling <constant>VIDIOC_QUERYBUF</constant> with a pointer to this structure drivers return an error code or fill the rest of the structure.</para> @@ -68,8 +69,8 @@ the structure.</para> <constant>V4L2_BUF_FLAG_MAPPED</constant>, <constant>V4L2_BUF_FLAG_QUEUED</constant> and <constant>V4L2_BUF_FLAG_DONE</constant> flags will be valid. The -<structfield>memory</structfield> field will be set to -<constant>V4L2_MEMORY_MMAP</constant>, the <structfield>m.offset</structfield> +<structfield>memory</structfield> field will be set to the current +I/O method, the <structfield>m.offset</structfield> contains the offset of the buffer from the start of the device memory, the <structfield>length</structfield> field its size. The driver may or may not set the remaining fields and flags, they are meaningless in diff --git a/Documentation/DocBook/v4l/vidioc-reqbufs.xml b/Documentation/DocBook/v4l/vidioc-reqbufs.xml index bab38084454f..1c0816372074 100644 --- a/Documentation/DocBook/v4l/vidioc-reqbufs.xml +++ b/Documentation/DocBook/v4l/vidioc-reqbufs.xml @@ -54,23 +54,23 @@ I/O. Memory mapped buffers are located in device memory and must be allocated with this ioctl before they can be mapped into the application's address space. User buffers are allocated by applications themselves, and this ioctl is merely used to switch the -driver into user pointer I/O mode.</para> +driver into user pointer I/O mode and to setup some internal structures.</para> - <para>To allocate device buffers applications initialize three -fields of a <structname>v4l2_requestbuffers</structname> structure. + <para>To allocate device buffers applications initialize all +fields of the <structname>v4l2_requestbuffers</structname> structure. They set the <structfield>type</structfield> field to the respective stream or buffer type, the <structfield>count</structfield> field to -the desired number of buffers, and <structfield>memory</structfield> -must be set to <constant>V4L2_MEMORY_MMAP</constant>. When the ioctl -is called with a pointer to this structure the driver attempts to -allocate the requested number of buffers and stores the actual number +the desired number of buffers, <structfield>memory</structfield> +must be set to the requested I/O method and the reserved array +must be zeroed. When the ioctl +is called with a pointer to this structure the driver will attempt to allocate +the requested number of buffers and it stores the actual number allocated in the <structfield>count</structfield> field. It can be smaller than the number requested, even zero, when the driver runs out -of free memory. A larger number is possible when the driver requires -more buffers to function correctly.<footnote> - <para>For example video output requires at least two buffers, +of free memory. A larger number is also possible when the driver requires +more buffers to function correctly. For example video output requires at least two buffers, one displayed and one filled by the application.</para> - </footnote> When memory mapping I/O is not supported the ioctl + <para>When the I/O method is not supported the ioctl returns an &EINVAL;.</para> <para>Applications can call <constant>VIDIOC_REQBUFS</constant> @@ -81,14 +81,6 @@ in progress, an implicit &VIDIOC-STREAMOFF;. <!-- mhs: I see no reason why munmap()ping one or even all buffers must imply streamoff.--></para> - <para>To negotiate user pointer I/O, applications initialize only -the <structfield>type</structfield> field and set -<structfield>memory</structfield> to -<constant>V4L2_MEMORY_USERPTR</constant>. When the ioctl is called -with a pointer to this structure the driver prepares for user pointer -I/O, when this I/O method is not supported the ioctl returns an -&EINVAL;.</para> - <table pgwide="1" frame="none" id="v4l2-requestbuffers"> <title>struct <structname>v4l2_requestbuffers</structname></title> <tgroup cols="3"> @@ -97,9 +89,7 @@ I/O, when this I/O method is not supported the ioctl returns an <row> <entry>__u32</entry> <entry><structfield>count</structfield></entry> - <entry>The number of buffers requested or granted. This -field is only used when <structfield>memory</structfield> is set to -<constant>V4L2_MEMORY_MMAP</constant>.</entry> + <entry>The number of buffers requested or granted.</entry> </row> <row> <entry>&v4l2-buf-type;</entry> @@ -120,7 +110,7 @@ as the &v4l2-format; <structfield>type</structfield> field. See <xref <entry><structfield>reserved</structfield>[2]</entry> <entry>A place holder for future extensions and custom (driver defined) buffer types <constant>V4L2_BUF_TYPE_PRIVATE</constant> and -higher.</entry> +higher. This array should be zeroed by applications.</entry> </row> </tbody> </tgroup> diff --git a/Documentation/cachetlb.txt b/Documentation/cachetlb.txt index da42ab414c48..b231414bb8bc 100644 --- a/Documentation/cachetlb.txt +++ b/Documentation/cachetlb.txt @@ -377,3 +377,27 @@ maps this page at its virtual address. All the functionality of flush_icache_page can be implemented in flush_dcache_page and update_mmu_cache. In 2.7 the hope is to remove this interface completely. + +The final category of APIs is for I/O to deliberately aliased address +ranges inside the kernel. Such aliases are set up by use of the +vmap/vmalloc API. Since kernel I/O goes via physical pages, the I/O +subsystem assumes that the user mapping and kernel offset mapping are +the only aliases. This isn't true for vmap aliases, so anything in +the kernel trying to do I/O to vmap areas must manually manage +coherency. It must do this by flushing the vmap range before doing +I/O and invalidating it after the I/O returns. + + void flush_kernel_vmap_range(void *vaddr, int size) + flushes the kernel cache for a given virtual address range in + the vmap area. This is to make sure that any data the kernel + modified in the vmap range is made visible to the physical + page. The design is to make this area safe to perform I/O on. + Note that this API does *not* also flush the offset map alias + of the area. + + void invalidate_kernel_vmap_range(void *vaddr, int size) invalidates + the cache for a given virtual address range in the vmap area + which prevents the processor from making the cache stale by + speculatively reading data while the I/O was occurring to the + physical pages. This is only necessary for data reads into the + vmap area. diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index aed082f49d09..737988fca64d 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -145,8 +145,8 @@ show_sampling_rate_max: THIS INTERFACE IS DEPRECATED, DON'T USE IT. up_threshold: defines what the average CPU usage between the samplings of 'sampling_rate' needs to be for the kernel to make a decision on whether it should increase the frequency. For example when it is set -to its default value of '80' it means that between the checking -intervals the CPU needs to be on average more than 80% in use to then +to its default value of '95' it means that between the checking +intervals the CPU needs to be on average more than 95% in use to then decide that the CPU frequency needs to be increased. ignore_nice_load: this parameter takes a value of '0' or '1'. When diff --git a/Documentation/dontdiff b/Documentation/dontdiff index 3ad6acead949..d9bcffd59433 100644 --- a/Documentation/dontdiff +++ b/Documentation/dontdiff @@ -69,7 +69,6 @@ av_permissions.h bbootsect bin2c binkernel.spec -binoffset bootsect bounds.h bsetup diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index 14b7b5a3bcb9..239cbdbf4d12 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -26,7 +26,7 @@ use IO::Handle; "dec3000s", "vp7041", "dibusb", "nxt2002", "nxt2004", "or51211", "or51132_qam", "or51132_vsb", "bluebird", "opera1", "cx231xx", "cx18", "cx23885", "pvrusb2", "mpc718", - "af9015"); + "af9015", "ngene"); # Check args syntax() if (scalar(@ARGV) != 1); @@ -39,7 +39,7 @@ for ($i=0; $i < scalar(@components); $i++) { die $@ if $@; print STDERR <<EOF; Firmware(s) $outfile extracted successfully. -Now copy it(they) to either /usr/lib/hotplug/firmware or /lib/firmware +Now copy it(them) to either /usr/lib/hotplug/firmware or /lib/firmware (depending on configuration of firmware hotplug). EOF exit(0); @@ -549,6 +549,24 @@ sub af9015 { close INFILE; } +sub ngene { + my $url = "http://www.digitaldevices.de/download/"; + my $file1 = "ngene_15.fw"; + my $hash1 = "d798d5a757121174f0dbc5f2833c0c85"; + my $file2 = "ngene_17.fw"; + my $hash2 = "26b687136e127b8ac24b81e0eeafc20b"; + + checkstandard(); + + wgetfile($file1, $url . $file1); + verify($file1, $hash1); + + wgetfile($file2, $url . $file2); + verify($file2, $hash2); + + "$file1, $file2"; +} + # --------------------------------------------------------------- # Utilities @@ -667,6 +685,7 @@ sub delzero{ sub syntax() { print STDERR "syntax: get_dvb_firmware <component>\n"; print STDERR "Supported components:\n"; + @components = sort @components; for($i=0; $i < scalar(@components); $i++) { print STDERR "\t" . $components[$i] . "\n"; } diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt index 079305640790..7be15e44d481 100644 --- a/Documentation/fault-injection/fault-injection.txt +++ b/Documentation/fault-injection/fault-injection.txt @@ -143,8 +143,8 @@ o provide a way to configure fault attributes failslab, fail_page_alloc, and fail_make_request use this way. Helper functions: - init_fault_attr_entries(entries, attr, name); - void cleanup_fault_attr_entries(entries); + init_fault_attr_dentries(entries, attr, name); + void cleanup_fault_attr_dentries(entries); - module parameters diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 0a46833c1b76..b9eba900e0f0 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -64,6 +64,17 @@ Who: Robin Getz <rgetz@blackfin.uclinux.org> & Matt Mackall <mpm@selenic.com> --------------------------- +What: Deprecated snapshot ioctls +When: 2.6.36 + +Why: The ioctls in kernel/power/user.c were marked as deprecated long time + ago. Now they notify users about that so that they need to replace + their userspace. After some more time, remove them completely. + +Who: Jiri Slaby <jirislaby@gmail.com> + +--------------------------- + What: The ieee80211_regdom module parameter When: March 2010 / desktop catchup diff --git a/Documentation/input/multi-touch-protocol.txt b/Documentation/input/multi-touch-protocol.txt index a12ea3b586e6..8490480ce432 100644 --- a/Documentation/input/multi-touch-protocol.txt +++ b/Documentation/input/multi-touch-protocol.txt @@ -27,12 +27,30 @@ set of events/packets. A set of ABS_MT events with the desired properties is defined. The events are divided into categories, to allow for partial implementation. The -minimum set consists of ABS_MT_TOUCH_MAJOR, ABS_MT_POSITION_X and -ABS_MT_POSITION_Y, which allows for multiple fingers to be tracked. If the -device supports it, the ABS_MT_WIDTH_MAJOR may be used to provide the size -of the approaching finger. Anisotropy and direction may be specified with -ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and ABS_MT_ORIENTATION. The -ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a +minimum set consists of ABS_MT_POSITION_X and ABS_MT_POSITION_Y, which +allows for multiple fingers to be tracked. If the device supports it, the +ABS_MT_TOUCH_MAJOR and ABS_MT_WIDTH_MAJOR may be used to provide the size +of the contact area and approaching finger, respectively. + +The TOUCH and WIDTH parameters have a geometrical interpretation; imagine +looking through a window at someone gently holding a finger against the +glass. You will see two regions, one inner region consisting of the part +of the finger actually touching the glass, and one outer region formed by +the perimeter of the finger. The diameter of the inner region is the +ABS_MT_TOUCH_MAJOR, the diameter of the outer region is +ABS_MT_WIDTH_MAJOR. Now imagine the person pressing the finger harder +against the glass. The inner region will increase, and in general, the +ratio ABS_MT_TOUCH_MAJOR / ABS_MT_WIDTH_MAJOR, which is always smaller than +unity, is related to the finger pressure. For pressure-based devices, +ABS_MT_PRESSURE may be used to provide the pressure on the contact area +instead. + +In addition to the MAJOR parameters, the oval shape of the finger can be +described by adding the MINOR parameters, such that MAJOR and MINOR are the +major and minor axis of an ellipse. Finally, the orientation of the oval +shape can be describe with the ORIENTATION parameter. + +The ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a finger or a pen or something else. Devices with more granular information may specify general shapes as blobs, i.e., as a sequence of rectangular shapes grouped together by an ABS_MT_BLOB_ID. Finally, for the few devices @@ -42,11 +60,9 @@ report finger tracking from hardware [5]. Here is what a minimal event sequence for a two-finger touch would look like: - ABS_MT_TOUCH_MAJOR ABS_MT_POSITION_X ABS_MT_POSITION_Y SYN_MT_REPORT - ABS_MT_TOUCH_MAJOR ABS_MT_POSITION_X ABS_MT_POSITION_Y SYN_MT_REPORT @@ -87,6 +103,12 @@ the contact. The ratio ABS_MT_TOUCH_MAJOR / ABS_MT_WIDTH_MAJOR approximates the notion of pressure. The fingers of the hand and the palm all have different characteristic widths [1]. +ABS_MT_PRESSURE + +The pressure, in arbitrary units, on the contact area. May be used instead +of TOUCH and WIDTH for pressure-based devices or any device with a spatial +signal intensity distribution. + ABS_MT_ORIENTATION The orientation of the ellipse. The value should describe a signed quarter @@ -170,6 +192,16 @@ There are a few devices that support trackingID in hardware. User space can make use of these native identifiers to reduce bandwidth and cpu usage. +Gestures +-------- + +In the specific application of creating gesture events, the TOUCH and WIDTH +parameters can be used to, e.g., approximate finger pressure or distinguish +between index finger and thumb. With the addition of the MINOR parameters, +one can also distinguish between a sweeping finger and a pointing finger, +and with ORIENTATION, one can detect twisting of fingers. + + Notes ----- diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 736d45602886..db611e195ebb 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -199,6 +199,10 @@ and is between 256 and 4096 characters. It is defined in the file acpi_display_output=video See above. + acpi_early_pdc_eval [HW,ACPI] Evaluate processor _PDC methods + early. Needed on some platforms to properly + initialize the EC. + acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs default in APIC mode @@ -311,6 +315,11 @@ and is between 256 and 4096 characters. It is defined in the file aic79xx= [HW,SCSI] See Documentation/scsi/aic79xx.txt. + alignment= [KNL,ARM] + Allow the default userspace alignment fault handler + behaviour to be specified. Bit 0 enables warnings, + bit 1 enables fixups, and bit 2 sends a segfault. + amd_iommu= [HW,X86-84] Pass parameters to the AMD IOMMU driver in the system. Possible values are: @@ -1729,6 +1738,9 @@ and is between 256 and 4096 characters. It is defined in the file nomfgpt [X86-32] Disable Multi-Function General Purpose Timer usage (for AMD Geode machines). + nopat [X86] Disable PAT (page attribute table extension of + pagetables) support. + norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space @@ -1939,8 +1951,12 @@ and is between 256 and 4096 characters. It is defined in the file IRQ routing is enabled. noacpi [X86] Do not use ACPI for IRQ routing or for PCI scanning. - use_crs [X86] Use _CRS for PCI resource - allocation. + use_crs [X86] Use PCI host bridge window information + from ACPI. On BIOSes from 2008 or later, this + is enabled by default. If you need to use this, + please report a bug. + nocrs [X86] Ignore PCI host bridge windows from ACPI. + If you need to use this, please report a bug. routeirq Do IRQ routing for all PCI devices. This is normally done in pci_enable_device(), so this option is a temporary workaround @@ -1989,6 +2005,14 @@ and is between 256 and 4096 characters. It is defined in the file force Enable ASPM even on devices that claim not to support it. WARNING: Forcing ASPM on may cause system lockups. + pcie_pme= [PCIE,PM] Native PCIe PME signaling options: + off Do not use native PCIe PME signaling. + force Use native PCIe PME signaling even if the BIOS refuses + to allow the kernel to control the relevant PCIe config + registers. + nomsi Do not use MSI for native PCIe PME signaling (this makes + all PCIe root ports use INTx for everything). + pcmv= [HW,PCMCIA] BadgePAD 4 pd. [PARIDE] diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index 42208511b5c0..3119f5db75bd 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c @@ -34,7 +34,6 @@ #include <sys/uio.h> #include <termios.h> #include <getopt.h> -#include <zlib.h> #include <assert.h> #include <sched.h> #include <limits.h> diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 006b39dec87d..e87f3cdc8a6a 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -1074,10 +1074,10 @@ regen_max_retry - INTEGER Default: 5 max_addresses - INTEGER - Number of maximum addresses per interface. 0 disables limitation. - It is recommended not set too large value (or 0) because it would - be too easy way to crash kernel to allow to create too much of - autoconfigured addresses. + Maximum number of autoconfigured addresses per interface. Setting + to zero disables the limitation. It is not recommended to set this + value too large (or to zero) because it would be an easy way to + crash the kernel by allowing too many addresses to be created. Default: 16 disable_ipv6 - BOOLEAN diff --git a/Documentation/pcmcia/locking.txt b/Documentation/pcmcia/locking.txt new file mode 100644 index 000000000000..68f622bc4064 --- /dev/null +++ b/Documentation/pcmcia/locking.txt @@ -0,0 +1,118 @@ +This file explains the locking and exclusion scheme used in the PCCARD +and PCMCIA subsystems. + + +A) Overview, Locking Hierarchy: +=============================== + +pcmcia_socket_list_rwsem - protects only the list of sockets +- skt_mutex - serializes card insert / ejection + - ops_mutex - serializes socket operation + + +B) Exclusion +============ + +The following functions and callbacks to struct pcmcia_socket must +be called with "skt_mutex" held: + + socket_detect_change() + send_event() + socket_reset() + socket_shutdown() + socket_setup() + socket_remove() + socket_insert() + socket_early_resume() + socket_late_resume() + socket_resume() + socket_suspend() + + struct pcmcia_callback *callback + +The following functions and callbacks to struct pcmcia_socket must +be called with "ops_mutex" held: + + socket_reset() + socket_setup() + + struct pccard_operations *ops + struct pccard_resource_ops *resource_ops; + +Note that send_event() and struct pcmcia_callback *callback must not be +called with "ops_mutex" held. + + +C) Protection +============= + +1. Global Data: +--------------- +struct list_head pcmcia_socket_list; + +protected by pcmcia_socket_list_rwsem; + + +2. Per-Socket Data: +------------------- +The resource_ops and their data are protected by ops_mutex. + +The "main" struct pcmcia_socket is protected as follows (read-only fields +or single-use fields not mentioned): + +- by pcmcia_socket_list_rwsem: + struct list_head socket_list; + +- by thread_lock: + unsigned int thread_events; + +- by skt_mutex: + u_int suspended_state; + void (*tune_bridge); + struct pcmcia_callback *callback; + int resume_status; + +- by ops_mutex: + socket_state_t socket; + u_int state; + u_short lock_count; + pccard_mem_map cis_mem; + void __iomem *cis_virt; + struct { } irq; + io_window_t io[]; + pccard_mem_map win[]; + struct list_head cis_cache; + size_t fake_cis_len; + u8 *fake_cis; + u_int irq_mask; + void (*zoom_video); + int (*power_hook); + u8 resource...; + struct list_head devices_list; + u8 device_count; + struct pcmcia_state; + + +3. Per PCMCIA-device Data: +-------------------------- + +The "main" struct pcmcia_devie is protected as follows (read-only fields +or single-use fields not mentioned): + + +- by pcmcia_socket->ops_mutex: + struct list_head socket_device_list; + struct config_t *function_config; + u16 _irq:1; + u16 _io:1; + u16 _win:4; + u16 _locked:1; + u16 allow_func_id_match:1; + u16 suspended:1; + u16 _removed:1; + +- by the PCMCIA driver: + io_req_t io; + irq_req_t irq; + config_req_t conf; + window_handle_t win; diff --git a/Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt b/Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt new file mode 100644 index 000000000000..8832e8798912 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt @@ -0,0 +1,70 @@ +MPC5121 PSC Device Tree Bindings + +PSC in UART mode +---------------- + +For PSC in UART mode the needed PSC serial devices +are specified by fsl,mpc5121-psc-uart nodes in the +fsl,mpc5121-immr SoC node. Additionally the PSC FIFO +Controller node fsl,mpc5121-psc-fifo is requered there: + +fsl,mpc5121-psc-uart nodes +-------------------------- + +Required properties : + - compatible : Should contain "fsl,mpc5121-psc-uart" and "fsl,mpc5121-psc" + - cell-index : Index of the PSC in hardware + - reg : Offset and length of the register set for the PSC device + - interrupts : <a b> where a is the interrupt number of the + PSC FIFO Controller and b is a field that represents an + encoding of the sense and level information for the interrupt. + - interrupt-parent : the phandle for the interrupt controller that + services interrupts for this device. + +Recommended properties : + - fsl,rx-fifo-size : the size of the RX fifo slice (a multiple of 4) + - fsl,tx-fifo-size : the size of the TX fifo slice (a multiple of 4) + + +fsl,mpc5121-psc-fifo node +------------------------- + +Required properties : + - compatible : Should be "fsl,mpc5121-psc-fifo" + - reg : Offset and length of the register set for the PSC + FIFO Controller + - interrupts : <a b> where a is the interrupt number of the + PSC FIFO Controller and b is a field that represents an + encoding of the sense and level information for the interrupt. + - interrupt-parent : the phandle for the interrupt controller that + services interrupts for this device. + + +Example for a board using PSC0 and PSC1 devices in serial mode: + +serial@11000 { + compatible = "fsl,mpc5121-psc-uart", "fsl,mpc5121-psc"; + cell-index = <0>; + reg = <0x11000 0x100>; + interrupts = <40 0x8>; + interrupt-parent = < &ipic >; + fsl,rx-fifo-size = <16>; + fsl,tx-fifo-size = <16>; +}; + +serial@11100 { + compatible = "fsl,mpc5121-psc-uart", "fsl,mpc5121-psc"; + cell-index = <1>; + reg = <0x11100 0x100>; + interrupts = <40 0x8>; + interrupt-parent = < &ipic >; + fsl,rx-fifo-size = <16>; + fsl,tx-fifo-size = <16>; +}; + +pscfifo@11f00 { + compatible = "fsl,mpc5121-psc-fifo"; + reg = <0x11f00 0x100>; + interrupts = <40 0x8>; + interrupt-parent = < &ipic >; +}; diff --git a/Documentation/powerpc/dts-bindings/fsl/spi.txt b/Documentation/powerpc/dts-bindings/fsl/spi.txt index e7d9a344c4f4..80510c018eea 100644 --- a/Documentation/powerpc/dts-bindings/fsl/spi.txt +++ b/Documentation/powerpc/dts-bindings/fsl/spi.txt @@ -13,6 +13,11 @@ Required properties: - interrupt-parent : the phandle for the interrupt controller that services interrupts for this device. +Optional properties: +- gpios : specifies the gpio pins to be used for chipselects. + The gpios will be referred to as reg = <index> in the SPI child nodes. + If unspecified, a single SPI device without a chip select can be used. + Example: spi@4c0 { cell-index = <0>; @@ -21,4 +26,6 @@ Example: interrupts = <82 0>; interrupt-parent = <700>; mode = "cpu"; + gpios = <&gpio 18 1 // device reg=<0> + &gpio 19 1>; // device reg=<1> }; diff --git a/Documentation/powerpc/ptrace.txt b/Documentation/powerpc/ptrace.txt new file mode 100644 index 000000000000..f4a5499b7bc6 --- /dev/null +++ b/Documentation/powerpc/ptrace.txt @@ -0,0 +1,134 @@ +GDB intends to support the following hardware debug features of BookE +processors: + +4 hardware breakpoints (IAC) +2 hardware watchpoints (read, write and read-write) (DAC) +2 value conditions for the hardware watchpoints (DVC) + +For that, we need to extend ptrace so that GDB can query and set these +resources. Since we're extending, we're trying to create an interface +that's extendable and that covers both BookE and server processors, so +that GDB doesn't need to special-case each of them. We added the +following 3 new ptrace requests. + +1. PTRACE_PPC_GETHWDEBUGINFO + +Query for GDB to discover the hardware debug features. The main info to +be returned here is the minimum alignment for the hardware watchpoints. +BookE processors don't have restrictions here, but server processors have +an 8-byte alignment restriction for hardware watchpoints. We'd like to avoid +adding special cases to GDB based on what it sees in AUXV. + +Since we're at it, we added other useful info that the kernel can return to +GDB: this query will return the number of hardware breakpoints, hardware +watchpoints and whether it supports a range of addresses and a condition. +The query will fill the following structure provided by the requesting process: + +struct ppc_debug_info { + unit32_t version; + unit32_t num_instruction_bps; + unit32_t num_data_bps; + unit32_t num_condition_regs; + unit32_t data_bp_alignment; + unit32_t sizeof_condition; /* size of the DVC register */ + uint64_t features; /* bitmask of the individual flags */ +}; + +features will have bits indicating whether there is support for: + +#define PPC_DEBUG_FEATURE_INSN_BP_RANGE 0x1 +#define PPC_DEBUG_FEATURE_INSN_BP_MASK 0x2 +#define PPC_DEBUG_FEATURE_DATA_BP_RANGE 0x4 +#define PPC_DEBUG_FEATURE_DATA_BP_MASK 0x8 + +2. PTRACE_SETHWDEBUG + +Sets a hardware breakpoint or watchpoint, according to the provided structure: + +struct ppc_hw_breakpoint { + uint32_t version; +#define PPC_BREAKPOINT_TRIGGER_EXECUTE 0x1 +#define PPC_BREAKPOINT_TRIGGER_READ 0x2 +#define PPC_BREAKPOINT_TRIGGER_WRITE 0x4 + uint32_t trigger_type; /* only some combinations allowed */ +#define PPC_BREAKPOINT_MODE_EXACT 0x0 +#define PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE 0x1 +#define PPC_BREAKPOINT_MODE_RANGE_EXCLUSIVE 0x2 +#define PPC_BREAKPOINT_MODE_MASK 0x3 + uint32_t addr_mode; /* address match mode */ + +#define PPC_BREAKPOINT_CONDITION_MODE 0x3 +#define PPC_BREAKPOINT_CONDITION_NONE 0x0 +#define PPC_BREAKPOINT_CONDITION_AND 0x1 +#define PPC_BREAKPOINT_CONDITION_EXACT 0x1 /* different name for the same thing as above */ +#define PPC_BREAKPOINT_CONDITION_OR 0x2 +#define PPC_BREAKPOINT_CONDITION_AND_OR 0x3 +#define PPC_BREAKPOINT_CONDITION_BE_ALL 0x00ff0000 /* byte enable bits */ +#define PPC_BREAKPOINT_CONDITION_BE(n) (1<<((n)+16)) + uint32_t condition_mode; /* break/watchpoint condition flags */ + + uint64_t addr; + uint64_t addr2; + uint64_t condition_value; +}; + +A request specifies one event, not necessarily just one register to be set. +For instance, if the request is for a watchpoint with a condition, both the +DAC and DVC registers will be set in the same request. + +With this GDB can ask for all kinds of hardware breakpoints and watchpoints +that the BookE supports. COMEFROM breakpoints available in server processors +are not contemplated, but that is out of the scope of this work. + +ptrace will return an integer (handle) uniquely identifying the breakpoint or +watchpoint just created. This integer will be used in the PTRACE_DELHWDEBUG +request to ask for its removal. Return -ENOSPC if the requested breakpoint +can't be allocated on the registers. + +Some examples of using the structure to: + +- set a breakpoint in the first breakpoint register + + p.version = PPC_DEBUG_CURRENT_VERSION; + p.trigger_type = PPC_BREAKPOINT_TRIGGER_EXECUTE; + p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; + p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; + p.addr = (uint64_t) address; + p.addr2 = 0; + p.condition_value = 0; + +- set a watchpoint which triggers on reads in the second watchpoint register + + p.version = PPC_DEBUG_CURRENT_VERSION; + p.trigger_type = PPC_BREAKPOINT_TRIGGER_READ; + p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; + p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; + p.addr = (uint64_t) address; + p.addr2 = 0; + p.condition_value = 0; + +- set a watchpoint which triggers only with a specific value + + p.version = PPC_DEBUG_CURRENT_VERSION; + p.trigger_type = PPC_BREAKPOINT_TRIGGER_READ; + p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; + p.condition_mode = PPC_BREAKPOINT_CONDITION_AND | PPC_BREAKPOINT_CONDITION_BE_ALL; + p.addr = (uint64_t) address; + p.addr2 = 0; + p.condition_value = (uint64_t) condition; + +- set a ranged hardware breakpoint + + p.version = PPC_DEBUG_CURRENT_VERSION; + p.trigger_type = PPC_BREAKPOINT_TRIGGER_EXECUTE; + p.addr_mode = PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE; + p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; + p.addr = (uint64_t) begin_range; + p.addr2 = (uint64_t) end_range; + p.condition_value = 0; + +3. PTRACE_DELHWDEBUG + +Takes an integer which identifies an existing breakpoint or watchpoint +(i.e., the value returned from PTRACE_SETHWDEBUG), and deletes the +corresponding breakpoint or watchpoint.. diff --git a/Documentation/s390/CommonIO b/Documentation/s390/CommonIO index 339207d11d95..d378cba66456 100644 --- a/Documentation/s390/CommonIO +++ b/Documentation/s390/CommonIO @@ -87,6 +87,12 @@ Command line parameters compatibility, by the device number in hexadecimal (0xabcd or abcd). Device numbers given as 0xabcd will be interpreted as 0.0.abcd. +* /proc/cio_settle + + A write request to this file is blocked until all queued cio actions are + handled. This will allow userspace to wait for pending work affecting + device availability after changing cio_ignore or the hardware configuration. + * For some of the information present in the /proc filesystem in 2.4 (namely, /proc/subchannels and /proc/chpids), see driver-model.txt. Information formerly in /proc/irq_count is now in /proc/interrupts. diff --git a/Documentation/s390/driver-model.txt b/Documentation/s390/driver-model.txt index bde473df748d..ed265cf54cde 100644 --- a/Documentation/s390/driver-model.txt +++ b/Documentation/s390/driver-model.txt @@ -223,8 +223,8 @@ touched by the driver - it should use the ccwgroup device's driver_data for its private data. To implement a ccwgroup driver, please refer to include/asm/ccwgroup.h. Keep in -mind that most drivers will need to implement both a ccwgroup and a ccw driver -(unless you have a meta ccw driver, like cu3088 for lcs and ctc). +mind that most drivers will need to implement both a ccwgroup and a ccw +driver. 2. Channel paths diff --git a/Documentation/scsi/ChangeLog.megaraid_sas b/Documentation/scsi/ChangeLog.megaraid_sas index 17ffa0607712..30023568805e 100644 --- a/Documentation/scsi/ChangeLog.megaraid_sas +++ b/Documentation/scsi/ChangeLog.megaraid_sas @@ -1,3 +1,19 @@ +1 Release Date : Thur. Oct 29, 2009 09:12:45 PST 2009 - + (emaild-id:megaraidlinux@lsi.com) + Bo Yang + +2 Current Version : 00.00.04.17.1-rc1 +3 Older Version : 00.00.04.12 + +1. Add the pad_0 in mfi frame structure to 0 to fix the + context value larger than 32bit value issue. + +2. Add the logic drive list to the driver. Driver will + keep the logic drive list internal after driver load. + +3. driver fixed the device update issue after get the AEN + PD delete/ADD, LD add/delete from FW. + 1 Release Date : Tues. July 28, 2009 10:12:45 PST 2009 - (emaild-id:megaraidlinux@lsi.com) Bo Yang diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt index 239f14b2b55a..6a5a579126b0 100644 --- a/Documentation/trace/ftrace-design.txt +++ b/Documentation/trace/ftrace-design.txt @@ -1,5 +1,6 @@ function tracer guts ==================== + By Mike Frysinger Introduction ------------ @@ -173,14 +174,16 @@ void ftrace_graph_caller(void) unsigned long *frompc = &...; unsigned long selfpc = <return address> - MCOUNT_INSN_SIZE; - prepare_ftrace_return(frompc, selfpc); + /* passing frame pointer up is optional -- see below */ + prepare_ftrace_return(frompc, selfpc, frame_pointer); /* restore all state needed by the ABI */ } #endif -For information on how to implement prepare_ftrace_return(), simply look at -the x86 version. The only architecture-specific piece in it is the setup of +For information on how to implement prepare_ftrace_return(), simply look at the +x86 version (the frame pointer passing is optional; see the next section for +more information). The only architecture-specific piece in it is the setup of the fault recovery table (the asm(...) code). The rest should be the same across architectures. @@ -205,6 +208,23 @@ void return_to_handler(void) #endif +HAVE_FUNCTION_GRAPH_FP_TEST +--------------------------- + +An arch may pass in a unique value (frame pointer) to both the entering and +exiting of a function. On exit, the value is compared and if it does not +match, then it will panic the kernel. This is largely a sanity check for bad +code generation with gcc. If gcc for your port sanely updates the frame +pointer under different opitmization levels, then ignore this option. + +However, adding support for it isn't terribly difficult. In your assembly code +that calls prepare_ftrace_return(), pass the frame pointer as the 3rd argument. +Then in the C version of that function, do what the x86 port does and pass it +along to ftrace_push_return_trace() instead of a stub value of 0. + +Similarly, when you call ftrace_return_to_handler(), pass it the frame pointer. + + HAVE_FTRACE_NMI_ENTER --------------------- diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt index 8179692fbb90..bab3040da548 100644 --- a/Documentation/trace/ftrace.txt +++ b/Documentation/trace/ftrace.txt @@ -1625,7 +1625,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt: # echo sys_nanosleep hrtimer_interrupt \ > set_ftrace_filter - # echo ftrace > current_tracer + # echo function > current_tracer # echo 1 > tracing_enabled # usleep 1 # echo 0 > tracing_enabled diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 7539e8fa1ffd..16ca030e1185 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 @@ -26,3 +26,4 @@ 25 -> Compro VideoMate E800 [1858:e800] 26 -> Hauppauge WinTV-HVR1290 [0070:8551] 27 -> Mygica X8558 PRO DMB-TH [14f1:8578] + 28 -> LEADTEK WinFast PxTV1200 [107d:6f22] diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index fce1e7eb0474..b4a767060ed7 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 @@ -174,3 +174,4 @@ 173 -> Zolid Hybrid TV Tuner PCI [1131:2004] 174 -> Asus Europa Hybrid OEM [1043:4847] 175 -> Leadtek Winfast DTV1000S [107d:6655] +176 -> Beholder BeholdTV 505 RDS [0000:5051] diff --git a/Documentation/video4linux/CARDLIST.tuner b/Documentation/video4linux/CARDLIST.tuner index e0d298fe8830..9b2e0dd6017e 100644 --- a/Documentation/video4linux/CARDLIST.tuner +++ b/Documentation/video4linux/CARDLIST.tuner @@ -81,3 +81,4 @@ tuner=80 - Philips FQ1216LME MK3 PAL/SECAM w/active loopthrough tuner=81 - Partsnic (Daewoo) PTI-5NF05 tuner=82 - Philips CU1216L tuner=83 - NXP TDA18271 +tuner=84 - Sony BTF-Pxn01Z diff --git a/Documentation/video4linux/README.tlg2300 b/Documentation/video4linux/README.tlg2300 new file mode 100644 index 000000000000..416ccb93d8c9 --- /dev/null +++ b/Documentation/video4linux/README.tlg2300 @@ -0,0 +1,47 @@ +tlg2300 release notes +==================== + +This is a v4l2/dvb device driver for the tlg2300 chip. + + +current status +============== + +video + - support mmap and read().(no overlay) + +audio + - The driver will register a ALSA card for the audio input. + +vbi + - Works for almost TV norms. + +dvb-t + - works for DVB-T + +FM + - Works for radio. + +--------------------------------------------------------------------------- +TESTED APPLICATIONS: + +-VLC1.0.4 test the video and dvb. The GUI is friendly to use. + +-Mplayer test the video. + +-Mplayer test the FM. The mplayer should be compiled with --enable-radio and + --enable-radio-capture. + The command runs as this(The alsa audio registers to card 1): + #mplayer radio://103.7/capture/ -radio adevice=hw=1,0:arate=48000 \ + -rawaudio rate=48000:channels=2 + +--------------------------------------------------------------------------- +KNOWN PROBLEMS: +about preemphasis: + You can set the preemphasis for radio by the following command: + #v4l2-ctl -d /dev/radio0 --set-ctrl=pre_emphasis_settings=1 + + "pre_emphasis_settings=1" means that you select the 50us. If you want + to select the 75us, please use "pre_emphasis_settings=2" + + diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index 1800a62cf135..181b9e6fd984 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt @@ -42,6 +42,7 @@ ov519 041e:4064 Creative Live! VISTA VF0420 ov519 041e:4067 Creative Live! Cam Video IM (VF0350) ov519 041e:4068 Creative Live! VISTA VF0470 spca561 0458:7004 Genius VideoCAM Express V2 +sn9c2028 0458:7005 Genius Smart 300, version 2 sunplus 0458:7006 Genius Dsc 1.3 Smart zc3xx 0458:7007 Genius VideoCam V2 zc3xx 0458:700c Genius VideoCam V3 @@ -109,6 +110,7 @@ sunplus 04a5:3003 Benq DC 1300 sunplus 04a5:3008 Benq DC 1500 sunplus 04a5:300a Benq DC 3410 spca500 04a5:300c Benq DC 1016 +benq 04a5:3035 Benq DC E300 finepix 04cb:0104 Fujifilm FinePix 4800 finepix 04cb:0109 Fujifilm FinePix A202 finepix 04cb:010b Fujifilm FinePix A203 @@ -142,6 +144,7 @@ sunplus 04fc:5360 Sunplus Generic spca500 04fc:7333 PalmPixDC85 sunplus 04fc:ffff Pure DigitalDakota spca501 0506:00df 3Com HomeConnect Lite +sunplus 052b:1507 Megapixel 5 Pretec DC-1007 sunplus 052b:1513 Megapix V4 sunplus 052b:1803 MegaImage VI tv8532 0545:808b Veo Stingray @@ -151,6 +154,7 @@ sunplus 0546:3191 Polaroid Ion 80 sunplus 0546:3273 Polaroid PDC2030 ov519 054c:0154 Sonny toy4 ov519 054c:0155 Sonny toy5 +cpia1 0553:0002 CPIA CPiA (version1) based cameras zc3xx 055f:c005 Mustek Wcam300A spca500 055f:c200 Mustek Gsmart 300 sunplus 055f:c211 Kowa Bs888e Microcamera @@ -188,8 +192,7 @@ spca500 06bd:0404 Agfa CL20 spca500 06be:0800 Optimedia sunplus 06d6:0031 Trust 610 LCD PowerC@m Zoom spca506 06e1:a190 ADS Instant VCD -ov534 06f8:3002 Hercules Blog Webcam -ov534 06f8:3003 Hercules Dualpix HD Weblog +ov534_9 06f8:3003 Hercules Dualpix HD Weblog sonixj 06f8:3004 Hercules Classic Silver sonixj 06f8:3008 Hercules Deluxe Optical Glass pac7302 06f8:3009 Hercules Classic Link @@ -204,6 +207,7 @@ sunplus 0733:2221 Mercury Digital Pro 3.1p sunplus 0733:3261 Concord 3045 spca536a sunplus 0733:3281 Cyberpix S550V spca506 0734:043b 3DeMon USB Capture aka +cpia1 0813:0001 QX3 camera ov519 0813:0002 Dual Mode USB Camera Plus spca500 084d:0003 D-Link DSC-350 spca500 08ca:0103 Aiptek PocketDV @@ -225,7 +229,8 @@ sunplus 08ca:2050 Medion MD 41437 sunplus 08ca:2060 Aiptek PocketDV5300 tv8532 0923:010f ICM532 cams mars 093a:050f Mars-Semi Pc-Camera -mr97310a 093a:010f Sakar Digital no. 77379 +mr97310a 093a:010e All known CIF cams with this ID +mr97310a 093a:010f All known VGA cams with this ID pac207 093a:2460 Qtec Webcam 100 pac207 093a:2461 HP Webcam pac207 093a:2463 Philips SPC 220 NC @@ -302,6 +307,7 @@ sonixj 0c45:613b Surfer SN-206 sonixj 0c45:613c Sonix Pccam168 sonixj 0c45:6143 Sonix Pccam168 sonixj 0c45:6148 Digitus DA-70811/ZSMC USB PC Camera ZS211/Microdia +sonixj 0c45:614a Frontech E-Ccam (JIL-2225) sn9c20x 0c45:6240 PC Camera (SN9C201 + MT9M001) sn9c20x 0c45:6242 PC Camera (SN9C201 + MT9M111) sn9c20x 0c45:6248 PC Camera (SN9C201 + OV9655) @@ -324,6 +330,10 @@ sn9c20x 0c45:62b0 PC Camera (SN9C202 + MT9V011/MT9V111/MT9V112) sn9c20x 0c45:62b3 PC Camera (SN9C202 + OV9655) sn9c20x 0c45:62bb PC Camera (SN9C202 + OV7660) sn9c20x 0c45:62bc PC Camera (SN9C202 + HV7131R) +sn9c2028 0c45:8001 Wild Planet Digital Spy Camera +sn9c2028 0c45:8003 Sakar #11199, #6637x, #67480 keychain cams +sn9c2028 0c45:8008 Mini-Shotz ms-350 +sn9c2028 0c45:800a Vivitar Vivicam 3350B sunplus 0d64:0303 Sunplus FashionCam DXG ov519 0e96:c001 TRUST 380 USB2 SPACEC@M etoms 102c:6151 Qcam Sangha CIF @@ -341,10 +351,11 @@ spca501 1776:501c Arowana 300K CMOS Camera t613 17a1:0128 TASCORP JPEG Webcam, NGS Cyclops vc032x 17ef:4802 Lenovo Vc0323+MI1310_SOC pac207 2001:f115 D-Link DSB-C120 -sq905c 2770:9050 sq905c -sq905c 2770:905c DualCamera -sq905 2770:9120 Argus Digital Camera DC1512 -sq905c 2770:913d sq905c +sq905c 2770:9050 Disney pix micro (CIF) +sq905c 2770:9052 Disney pix micro 2 (VGA) +sq905c 2770:905c All 11 known cameras with this ID +sq905 2770:9120 All 24 known cameras with this ID +sq905c 2770:913d All 4 known cameras with this ID spca500 2899:012c Toptro Industrial ov519 8020:ef04 ov519 spca508 8086:0110 Intel Easy PC Camera diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 74d677c8b036..5155700c206b 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -599,99 +599,13 @@ video_device::minor fields. video buffer helper functions ----------------------------- -The v4l2 core API provides a standard method for dealing with video -buffers. Those methods allow a driver to implement read(), mmap() and -overlay() on a consistent way. - -There are currently methods for using video buffers on devices that -supports DMA with scatter/gather method (videobuf-dma-sg), DMA with -linear access (videobuf-dma-contig), and vmalloced buffers, mostly -used on USB drivers (videobuf-vmalloc). - -Any driver using videobuf should provide operations (callbacks) for -four handlers: - -ops->buf_setup - calculates the size of the video buffers and avoid they - to waste more than some maximum limit of RAM; -ops->buf_prepare - fills the video buffer structs and calls - videobuf_iolock() to alloc and prepare mmaped memory; -ops->buf_queue - advices the driver that another buffer were - requested (by read() or by QBUF); -ops->buf_release - frees any buffer that were allocated. - -In order to use it, the driver need to have a code (generally called at -interrupt context) that will properly handle the buffer request lists, -announcing that a new buffer were filled. - -The irq handling code should handle the videobuf task lists, in order -to advice videobuf that a new frame were filled, in order to honor to a -request. The code is generally like this one: - if (list_empty(&dma_q->active)) - return; - - buf = list_entry(dma_q->active.next, struct vbuffer, vb.queue); - - if (!waitqueue_active(&buf->vb.done)) - return; - - /* Some logic to handle the buf may be needed here */ - - list_del(&buf->vb.queue); - do_gettimeofday(&buf->vb.ts); - wake_up(&buf->vb.done); - -Those are the videobuffer functions used on drivers, implemented on -videobuf-core: - -- Videobuf init functions - videobuf_queue_sg_init() - Initializes the videobuf infrastructure. This function should be - called before any other videobuf function on drivers that uses DMA - Scatter/Gather buffers. - - videobuf_queue_dma_contig_init - Initializes the videobuf infrastructure. This function should be - called before any other videobuf function on drivers that need DMA - contiguous buffers. - - videobuf_queue_vmalloc_init() - Initializes the videobuf infrastructure. This function should be - called before any other videobuf function on USB (and other drivers) - that need a vmalloced type of videobuf. - -- videobuf_iolock() - Prepares the videobuf memory for the proper method (read, mmap, overlay). - -- videobuf_queue_is_busy() - Checks if a videobuf is streaming. - -- videobuf_queue_cancel() - Stops video handling. - -- videobuf_mmap_free() - frees mmap buffers. - -- videobuf_stop() - Stops video handling, ends mmap and frees mmap and other buffers. - -- V4L2 api functions. Those functions correspond to VIDIOC_foo ioctls: - videobuf_reqbufs(), videobuf_querybuf(), videobuf_qbuf(), - videobuf_dqbuf(), videobuf_streamon(), videobuf_streamoff(). - -- V4L1 api function (corresponds to VIDIOCMBUF ioctl): - videobuf_cgmbuf() - This function is used to provide backward compatibility with V4L1 - API. - -- Some help functions for read()/poll() operations: - videobuf_read_stream() - For continuous stream read() - videobuf_read_one() - For snapshot read() - videobuf_poll_stream() - polling help function - -The better way to understand it is to take a look at vivi driver. One -of the main reasons for vivi is to be a videobuf usage example. the -vivi_thread_tick() does the task that the IRQ callback would do on PCI -drivers (or the irq callback on USB). +The v4l2 core API provides a set of standard methods (called "videobuf") +for dealing with video buffers. Those methods allow a driver to implement +read(), mmap() and overlay() in a consistent way. There are currently +methods for using video buffers on devices that supports DMA with +scatter/gather method (videobuf-dma-sg), DMA with linear access +(videobuf-dma-contig), and vmalloced buffers, mostly used on USB drivers +(videobuf-vmalloc). + +Please see Documentation/video4linux/videobuf for more information on how +to use the videobuf layer. diff --git a/Documentation/video4linux/videobuf b/Documentation/video4linux/videobuf new file mode 100644 index 000000000000..17a1f9abf260 --- /dev/null +++ b/Documentation/video4linux/videobuf @@ -0,0 +1,360 @@ +An introduction to the videobuf layer +Jonathan Corbet <corbet@lwn.net> +Current as of 2.6.33 + +The videobuf layer functions as a sort of glue layer between a V4L2 driver +and user space. It handles the allocation and management of buffers for +the storage of video frames. There is a set of functions which can be used +to implement many of the standard POSIX I/O system calls, including read(), +poll(), and, happily, mmap(). Another set of functions can be used to +implement the bulk of the V4L2 ioctl() calls related to streaming I/O, +including buffer allocation, queueing and dequeueing, and streaming +control. Using videobuf imposes a few design decisions on the driver +author, but the payback comes in the form of reduced code in the driver and +a consistent implementation of the V4L2 user-space API. + +Buffer types + +Not all video devices use the same kind of buffers. In fact, there are (at +least) three common variations: + + - Buffers which are scattered in both the physical and (kernel) virtual + address spaces. (Almost) all user-space buffers are like this, but it + makes great sense to allocate kernel-space buffers this way as well when + it is possible. Unfortunately, it is not always possible; working with + this kind of buffer normally requires hardware which can do + scatter/gather DMA operations. + + - Buffers which are physically scattered, but which are virtually + contiguous; buffers allocated with vmalloc(), in other words. These + buffers are just as hard to use for DMA operations, but they can be + useful in situations where DMA is not available but virtually-contiguous + buffers are convenient. + + - Buffers which are physically contiguous. Allocation of this kind of + buffer can be unreliable on fragmented systems, but simpler DMA + controllers cannot deal with anything else. + +Videobuf can work with all three types of buffers, but the driver author +must pick one at the outset and design the driver around that decision. + +[It's worth noting that there's a fourth kind of buffer: "overlay" buffers +which are located within the system's video memory. The overlay +functionality is considered to be deprecated for most use, but it still +shows up occasionally in system-on-chip drivers where the performance +benefits merit the use of this technique. Overlay buffers can be handled +as a form of scattered buffer, but there are very few implementations in +the kernel and a description of this technique is currently beyond the +scope of this document.] + +Data structures, callbacks, and initialization + +Depending on which type of buffers are being used, the driver should +include one of the following files: + + <media/videobuf-dma-sg.h> /* Physically scattered */ + <media/videobuf-vmalloc.h> /* vmalloc() buffers */ + <media/videobuf-dma-contig.h> /* Physically contiguous */ + +The driver's data structure describing a V4L2 device should include a +struct videobuf_queue instance for the management of the buffer queue, +along with a list_head for the queue of available buffers. There will also +need to be an interrupt-safe spinlock which is used to protect (at least) +the queue. + +The next step is to write four simple callbacks to help videobuf deal with +the management of buffers: + + struct videobuf_queue_ops { + int (*buf_setup)(struct videobuf_queue *q, + unsigned int *count, unsigned int *size); + int (*buf_prepare)(struct videobuf_queue *q, + struct videobuf_buffer *vb, + enum v4l2_field field); + void (*buf_queue)(struct videobuf_queue *q, + struct videobuf_buffer *vb); + void (*buf_release)(struct videobuf_queue *q, + struct videobuf_buffer *vb); + }; + +buf_setup() is called early in the I/O process, when streaming is being +initiated; its purpose is to tell videobuf about the I/O stream. The count +parameter will be a suggested number of buffers to use; the driver should +check it for rationality and adjust it if need be. As a practical rule, a +minimum of two buffers are needed for proper streaming, and there is +usually a maximum (which cannot exceed 32) which makes sense for each +device. The size parameter should be set to the expected (maximum) size +for each frame of data. + +Each buffer (in the form of a struct videobuf_buffer pointer) will be +passed to buf_prepare(), which should set the buffer's size, width, height, +and field fields properly. If the buffer's state field is +VIDEOBUF_NEEDS_INIT, the driver should pass it to: + + int videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb, + struct v4l2_framebuffer *fbuf); + +Among other things, this call will usually allocate memory for the buffer. +Finally, the buf_prepare() function should set the buffer's state to +VIDEOBUF_PREPARED. + +When a buffer is queued for I/O, it is passed to buf_queue(), which should +put it onto the driver's list of available buffers and set its state to +VIDEOBUF_QUEUED. Note that this function is called with the queue spinlock +held; if it tries to acquire it as well things will come to a screeching +halt. Yes, this is the voice of experience. Note also that videobuf may +wait on the first buffer in the queue; placing other buffers in front of it +could again gum up the works. So use list_add_tail() to enqueue buffers. + +Finally, buf_release() is called when a buffer is no longer intended to be +used. The driver should ensure that there is no I/O active on the buffer, +then pass it to the appropriate free routine(s): + + /* Scatter/gather drivers */ + int videobuf_dma_unmap(struct videobuf_queue *q, + struct videobuf_dmabuf *dma); + int videobuf_dma_free(struct videobuf_dmabuf *dma); + + /* vmalloc drivers */ + void videobuf_vmalloc_free (struct videobuf_buffer *buf); + + /* Contiguous drivers */ + void videobuf_dma_contig_free(struct videobuf_queue *q, + struct videobuf_buffer *buf); + +One way to ensure that a buffer is no longer under I/O is to pass it to: + + int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr); + +Here, vb is the buffer, non_blocking indicates whether non-blocking I/O +should be used (it should be zero in the buf_release() case), and intr +controls whether an interruptible wait is used. + +File operations + +At this point, much of the work is done; much of the rest is slipping +videobuf calls into the implementation of the other driver callbacks. The +first step is in the open() function, which must initialize the +videobuf queue. The function to use depends on the type of buffer used: + + void videobuf_queue_sg_init(struct videobuf_queue *q, + struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv); + + void videobuf_queue_vmalloc_init(struct videobuf_queue *q, + struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv); + + void videobuf_queue_dma_contig_init(struct videobuf_queue *q, + struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv); + +In each case, the parameters are the same: q is the queue structure for the +device, ops is the set of callbacks as described above, dev is the device +structure for this video device, irqlock is an interrupt-safe spinlock to +protect access to the data structures, type is the buffer type used by the +device (cameras will use V4L2_BUF_TYPE_VIDEO_CAPTURE, for example), field +describes which field is being captured (often V4L2_FIELD_NONE for +progressive devices), msize is the size of any containing structure used +around struct videobuf_buffer, and priv is a private data pointer which +shows up in the priv_data field of struct videobuf_queue. Note that these +are void functions which, evidently, are immune to failure. + +V4L2 capture drivers can be written to support either of two APIs: the +read() system call and the rather more complicated streaming mechanism. As +a general rule, it is necessary to support both to ensure that all +applications have a chance of working with the device. Videobuf makes it +easy to do that with the same code. To implement read(), the driver need +only make a call to one of: + + ssize_t videobuf_read_one(struct videobuf_queue *q, + char __user *data, size_t count, + loff_t *ppos, int nonblocking); + + ssize_t videobuf_read_stream(struct videobuf_queue *q, + char __user *data, size_t count, + loff_t *ppos, int vbihack, int nonblocking); + +Either one of these functions will read frame data into data, returning the +amount actually read; the difference is that videobuf_read_one() will only +read a single frame, while videobuf_read_stream() will read multiple frames +if they are needed to satisfy the count requested by the application. A +typical driver read() implementation will start the capture engine, call +one of the above functions, then stop the engine before returning (though a +smarter implementation might leave the engine running for a little while in +anticipation of another read() call happening in the near future). + +The poll() function can usually be implemented with a direct call to: + + unsigned int videobuf_poll_stream(struct file *file, + struct videobuf_queue *q, + poll_table *wait); + +Note that the actual wait queue eventually used will be the one associated +with the first available buffer. + +When streaming I/O is done to kernel-space buffers, the driver must support +the mmap() system call to enable user space to access the data. In many +V4L2 drivers, the often-complex mmap() implementation simplifies to a +single call to: + + int videobuf_mmap_mapper(struct videobuf_queue *q, + struct vm_area_struct *vma); + +Everything else is handled by the videobuf code. + +The release() function requires two separate videobuf calls: + + void videobuf_stop(struct videobuf_queue *q); + int videobuf_mmap_free(struct videobuf_queue *q); + +The call to videobuf_stop() terminates any I/O in progress - though it is +still up to the driver to stop the capture engine. The call to +videobuf_mmap_free() will ensure that all buffers have been unmapped; if +so, they will all be passed to the buf_release() callback. If buffers +remain mapped, videobuf_mmap_free() returns an error code instead. The +purpose is clearly to cause the closing of the file descriptor to fail if +buffers are still mapped, but every driver in the 2.6.32 kernel cheerfully +ignores its return value. + +ioctl() operations + +The V4L2 API includes a very long list of driver callbacks to respond to +the many ioctl() commands made available to user space. A number of these +- those associated with streaming I/O - turn almost directly into videobuf +calls. The relevant helper functions are: + + int videobuf_reqbufs(struct videobuf_queue *q, + struct v4l2_requestbuffers *req); + int videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b); + int videobuf_qbuf(struct videobuf_queue *q, struct v4l2_buffer *b); + int videobuf_dqbuf(struct videobuf_queue *q, struct v4l2_buffer *b, + int nonblocking); + int videobuf_streamon(struct videobuf_queue *q); + int videobuf_streamoff(struct videobuf_queue *q); + int videobuf_cgmbuf(struct videobuf_queue *q, struct video_mbuf *mbuf, + int count); + +So, for example, a VIDIOC_REQBUFS call turns into a call to the driver's +vidioc_reqbufs() callback which, in turn, usually only needs to locate the +proper struct videobuf_queue pointer and pass it to videobuf_reqbufs(). +These support functions can replace a great deal of buffer management +boilerplate in a lot of V4L2 drivers. + +The vidioc_streamon() and vidioc_streamoff() functions will be a bit more +complex, of course, since they will also need to deal with starting and +stopping the capture engine. videobuf_cgmbuf(), called from the driver's +vidiocgmbuf() function, only exists if the V4L1 compatibility module has +been selected with CONFIG_VIDEO_V4L1_COMPAT, so its use must be surrounded +with #ifdef directives. + +Buffer allocation + +Thus far, we have talked about buffers, but have not looked at how they are +allocated. The scatter/gather case is the most complex on this front. For +allocation, the driver can leave buffer allocation entirely up to the +videobuf layer; in this case, buffers will be allocated as anonymous +user-space pages and will be very scattered indeed. If the application is +using user-space buffers, no allocation is needed; the videobuf layer will +take care of calling get_user_pages() and filling in the scatterlist array. + +If the driver needs to do its own memory allocation, it should be done in +the vidioc_reqbufs() function, *after* calling videobuf_reqbufs(). The +first step is a call to: + + struct videobuf_dmabuf *videobuf_to_dma(struct videobuf_buffer *buf); + +The returned videobuf_dmabuf structure (defined in +<media/videobuf-dma-sg.h>) includes a couple of relevant fields: + + struct scatterlist *sglist; + int sglen; + +The driver must allocate an appropriately-sized scatterlist array and +populate it with pointers to the pieces of the allocated buffer; sglen +should be set to the length of the array. + +Drivers using the vmalloc() method need not (and cannot) concern themselves +with buffer allocation at all; videobuf will handle those details. The +same is normally true of contiguous-DMA drivers as well; videobuf will +allocate the buffers (with dma_alloc_coherent()) when it sees fit. That +means that these drivers may be trying to do high-order allocations at any +time, an operation which is not always guaranteed to work. Some drivers +play tricks by allocating DMA space at system boot time; videobuf does not +currently play well with those drivers. + +As of 2.6.31, contiguous-DMA drivers can work with a user-supplied buffer, +as long as that buffer is physically contiguous. Normal user-space +allocations will not meet that criterion, but buffers obtained from other +kernel drivers, or those contained within huge pages, will work with these +drivers. + +Filling the buffers + +The final part of a videobuf implementation has no direct callback - it's +the portion of the code which actually puts frame data into the buffers, +usually in response to interrupts from the device. For all types of +drivers, this process works approximately as follows: + + - Obtain the next available buffer and make sure that somebody is actually + waiting for it. + + - Get a pointer to the memory and put video data there. + + - Mark the buffer as done and wake up the process waiting for it. + +Step (1) above is done by looking at the driver-managed list_head structure +- the one which is filled in the buf_queue() callback. Because starting +the engine and enqueueing buffers are done in separate steps, it's possible +for the engine to be running without any buffers available - in the +vmalloc() case especially. So the driver should be prepared for the list +to be empty. It is equally possible that nobody is yet interested in the +buffer; the driver should not remove it from the list or fill it until a +process is waiting on it. That test can be done by examining the buffer's +done field (a wait_queue_head_t structure) with waitqueue_active(). + +A buffer's state should be set to VIDEOBUF_ACTIVE before being mapped for +DMA; that ensures that the videobuf layer will not try to do anything with +it while the device is transferring data. + +For scatter/gather drivers, the needed memory pointers will be found in the +scatterlist structure described above. Drivers using the vmalloc() method +can get a memory pointer with: + + void *videobuf_to_vmalloc(struct videobuf_buffer *buf); + +For contiguous DMA drivers, the function to use is: + + dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf); + +The contiguous DMA API goes out of its way to hide the kernel-space address +of the DMA buffer from drivers. + +The final step is to set the size field of the relevant videobuf_buffer +structure to the actual size of the captured image, set state to +VIDEOBUF_DONE, then call wake_up() on the done queue. At this point, the +buffer is owned by the videobuf layer and the driver should not touch it +again. + +Developers who are interested in more information can go into the relevant +header files; there are a few low-level functions declared there which have +not been talked about here. Also worthwhile is the vivi driver +(drivers/media/video/vivi.c), which is maintained as an example of how V4L2 +drivers should be written. Vivi only uses the vmalloc() API, but it's good +enough to get started with. Note also that all of these calls are exported +GPL-only, so they will not be available to non-GPL kernel modules. |