diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/block/queue-sysfs.txt | 63 | ||||
-rw-r--r-- | Documentation/cpu-freq/user-guide.txt | 16 | ||||
-rw-r--r-- | Documentation/filesystems/sysfs-pci.txt | 13 | ||||
-rw-r--r-- | Documentation/filesystems/ubifs.txt | 7 | ||||
-rw-r--r-- | Documentation/powerpc/dts-bindings/fsl/mpc5200.txt | 180 | ||||
-rw-r--r-- | Documentation/powerpc/mpc52xx-device-tree-bindings.txt | 277 | ||||
-rw-r--r-- | Documentation/video4linux/v4lgrab.c | 25 |
7 files changed, 272 insertions, 309 deletions
diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt new file mode 100644 index 00000000000..e164403f60e --- /dev/null +++ b/Documentation/block/queue-sysfs.txt @@ -0,0 +1,63 @@ +Queue sysfs files +================= + +This text file will detail the queue files that are located in the sysfs tree +for each block device. Note that stacked devices typically do not export +any settings, since their queue merely functions are a remapping target. +These files are the ones found in the /sys/block/xxx/queue/ directory. + +Files denoted with a RO postfix are readonly and the RW postfix means +read-write. + +hw_sector_size (RO) +------------------- +This is the hardware sector size of the device, in bytes. + +max_hw_sectors_kb (RO) +---------------------- +This is the maximum number of kilobytes supported in a single data transfer. + +max_sectors_kb (RW) +------------------- +This is the maximum number of kilobytes that the block layer will allow +for a filesystem request. Must be smaller than or equal to the maximum +size allowed by the hardware. + +nomerges (RW) +------------- +This enables the user to disable the lookup logic involved with IO merging +requests in the block layer. Merging may still occur through a direct +1-hit cache, since that comes for (almost) free. The IO scheduler will not +waste cycles doing tree/hash lookups for merges if nomerges is 1. Defaults +to 0, enabling all merges. + +nr_requests (RW) +---------------- +This controls how many requests may be allocated in the block layer for +read or write requests. Note that the total allocated number may be twice +this amount, since it applies only to reads or writes (not the accumulated +sum). + +read_ahead_kb (RW) +------------------ +Maximum number of kilobytes to read-ahead for filesystems on this block +device. + +rq_affinity (RW) +---------------- +If this option is enabled, the block layer will migrate request completions +to the CPU that originally submitted the request. For some workloads +this provides a significant reduction in CPU cycles due to caching effects. + +scheduler (RW) +-------------- +When read, this file will display the current and available IO schedulers +for this block device. The currently active IO scheduler will be enclosed +in [] brackets. Writing an IO scheduler name to this file will switch +control of this block device to that new IO scheduler. Note that writing +an IO scheduler name to this file will attempt to load that IO scheduler +module, if it isn't already present in the system. + + + +Jens Axboe <jens.axboe@oracle.com>, February 2009 diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt index e3443ddcfb8..917918f84fc 100644 --- a/Documentation/cpu-freq/user-guide.txt +++ b/Documentation/cpu-freq/user-guide.txt @@ -195,19 +195,3 @@ scaling_setspeed. By "echoing" a new frequency into this you can change the speed of the CPU, but only within the limits of scaling_min_freq and scaling_max_freq. - - -3.2 Deprecated Interfaces -------------------------- - -Depending on your kernel configuration, you might find the following -cpufreq-related files: -/proc/cpufreq -/proc/sys/cpu/*/speed -/proc/sys/cpu/*/speed-min -/proc/sys/cpu/*/speed-max - -These are files for deprecated interfaces to cpufreq, which offer far -less functionality. Because of this, these interfaces aren't described -here. - diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 68ef48839c0..9f8740ca3f3 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt @@ -9,6 +9,7 @@ that support it. For example, a given bus might look like this: | |-- class | |-- config | |-- device + | |-- enable | |-- irq | |-- local_cpus | |-- resource @@ -32,6 +33,7 @@ files, each with their own function. class PCI class (ascii, ro) config PCI config space (binary, rw) device PCI device (ascii, ro) + enable Whether the device is enabled (ascii, rw) irq IRQ number (ascii, ro) local_cpus nearby CPU mask (cpumask, ro) resource PCI resource host addresses (ascii, ro) @@ -57,10 +59,19 @@ used to do actual device programming from userspace. Note that some platforms don't support mmapping of certain resources, so be sure to check the return value from any attempted mmap. +The 'enable' file provides a counter that indicates how many times the device +has been enabled. If the 'enable' file currently returns '4', and a '1' is +echoed into it, it will then return '5'. Echoing a '0' into it will decrease +the count. Even when it returns to 0, though, some of the initialisation +may not be reversed. + The 'rom' file is special in that it provides read-only access to the device's ROM file, if available. It's disabled by default, however, so applications should write the string "1" to the file to enable it before attempting a read -call, and disable it following the access by writing "0" to the file. +call, and disable it following the access by writing "0" to the file. Note +that the device must be enabled for a rom read to return data succesfully. +In the event a driver is not bound to the device, it can be enabled using the +'enable' file, documented above. Accessing legacy resources through sysfs ---------------------------------------- diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt index 84da2a4ba25..12fedb7834c 100644 --- a/Documentation/filesystems/ubifs.txt +++ b/Documentation/filesystems/ubifs.txt @@ -79,13 +79,6 @@ Mount options (*) == default. -norm_unmount (*) commit on unmount; the journal is committed - when the file-system is unmounted so that the - next mount does not have to replay the journal - and it becomes very fast; -fast_unmount do not commit on unmount; this option makes - unmount faster, but the next mount slower - because of the need to replay the journal. bulk_read read more in one go to take advantage of flash media that read faster sequentially no_bulk_read (*) do not bulk-read diff --git a/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt b/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt new file mode 100644 index 00000000000..8447fd7090d --- /dev/null +++ b/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt @@ -0,0 +1,180 @@ +MPC5200 Device Tree Bindings +---------------------------- + +(c) 2006-2009 Secret Lab Technologies Ltd +Grant Likely <grant.likely@secretlab.ca> + +Naming conventions +------------------ +For mpc5200 on-chip devices, the format for each compatible value is +<chip>-<device>[-<mode>]. The OS should be able to match a device driver +to the device based solely on the compatible value. If two drivers +match on the compatible list; the 'most compatible' driver should be +selected. + +The split between the MPC5200 and the MPC5200B leaves a bit of a +conundrum. How should the compatible property be set up to provide +maximum compatibility information; but still accurately describe the +chip? For the MPC5200; the answer is easy. Most of the SoC devices +originally appeared on the MPC5200. Since they didn't exist anywhere +else; the 5200 compatible properties will contain only one item; +"fsl,mpc5200-<device>". + +The 5200B is almost the same as the 5200, but not quite. It fixes +silicon bugs and it adds a small number of enhancements. Most of the +devices either provide exactly the same interface as on the 5200. A few +devices have extra functions but still have a backwards compatible mode. +To express this information as completely as possible, 5200B device trees +should have two items in the compatible list: + compatible = "fsl,mpc5200b-<device>","fsl,mpc5200-<device>"; + +It is *strongly* recommended that 5200B device trees follow this convention +(instead of only listing the base mpc5200 item). + +ie. ethernet on mpc5200: compatible = "fsl,mpc5200-fec"; + ethernet on mpc5200b: compatible = "fsl,mpc5200b-fec", "fsl,mpc5200-fec"; + +Modal devices, like PSCs, also append the configured function to the +end of the compatible field. ie. A PSC in i2s mode would specify +"fsl,mpc5200-psc-i2s", not "fsl,mpc5200-i2s". This convention is chosen to +avoid naming conflicts with non-psc devices providing the same +function. For example, "fsl,mpc5200-spi" and "fsl,mpc5200-psc-spi" describe +the mpc5200 simple spi device and a PSC spi mode respectively. + +At the time of writing, exact chip may be either 'fsl,mpc5200' or +'fsl,mpc5200b'. + +The soc node +------------ +This node describes the on chip SOC peripherals. Every mpc5200 based +board will have this node, and as such there is a common naming +convention for SOC devices. + +Required properties: +name description +---- ----------- +ranges Memory range of the internal memory mapped registers. + Should be <0 [baseaddr] 0xc000> +reg Should be <[baseaddr] 0x100> +compatible mpc5200: "fsl,mpc5200-immr" + mpc5200b: "fsl,mpc5200b-immr" +system-frequency 'fsystem' frequency in Hz; XLB, IPB, USB and PCI + clocks are derived from the fsystem clock. +bus-frequency IPB bus frequency in Hz. Clock rate + used by most of the soc devices. + +soc child nodes +--------------- +Any on chip SOC devices available to Linux must appear as soc5200 child nodes. + +Note: The tables below show the value for the mpc5200. A mpc5200b device +tree should use the "fsl,mpc5200b-<device>","fsl,mpc5200-<device>" form. + +Required soc5200 child nodes: +name compatible Description +---- ---------- ----------- +cdm@<addr> fsl,mpc5200-cdm Clock Distribution +interrupt-controller@<addr> fsl,mpc5200-pic need an interrupt + controller to boot +bestcomm@<addr> fsl,mpc5200-bestcomm Bestcomm DMA controller + +Recommended soc5200 child nodes; populate as needed for your board +name compatible Description +---- ---------- ----------- +timer@<addr> fsl,mpc5200-gpt General purpose timers +gpio@<addr> fsl,mpc5200-gpio MPC5200 simple gpio controller +gpio@<addr> fsl,mpc5200-gpio-wkup MPC5200 wakeup gpio controller +rtc@<addr> fsl,mpc5200-rtc Real time clock +mscan@<addr> fsl,mpc5200-mscan CAN bus controller +pci@<addr> fsl,mpc5200-pci PCI bridge +serial@<addr> fsl,mpc5200-psc-uart PSC in serial mode +i2s@<addr> fsl,mpc5200-psc-i2s PSC in i2s mode +ac97@<addr> fsl,mpc5200-psc-ac97 PSC in ac97 mode +spi@<addr> fsl,mpc5200-psc-spi PSC in spi mode +irda@<addr> fsl,mpc5200-psc-irda PSC in IrDA mode +spi@<addr> fsl,mpc5200-spi MPC5200 spi device +ethernet@<addr> fsl,mpc5200-fec MPC5200 ethernet device +ata@<addr> fsl,mpc5200-ata IDE ATA interface +i2c@<addr> fsl,mpc5200-i2c I2C controller +usb@<addr> fsl,mpc5200-ohci,ohci-be USB controller +xlb@<addr> fsl,mpc5200-xlb XLB arbitrator + +fsl,mpc5200-gpt nodes +--------------------- +On the mpc5200 and 5200b, GPT0 has a watchdog timer function. If the board +design supports the internal wdt, then the device node for GPT0 should +include the empty property 'fsl,has-wdt'. + +An mpc5200-gpt can be used as a single line GPIO controller. To do so, +add the following properties to the gpt node: + gpio-controller; + #gpio-cells = <2>; +When referencing the GPIO line from another node, the first cell must always +be zero and the second cell represents the gpio flags and described in the +gpio device tree binding. + +An mpc5200-gpt can be used as a single line edge sensitive interrupt +controller. To do so, add the following properties to the gpt node: + interrupt-controller; + #interrupt-cells = <1>; +When referencing the IRQ line from another node, the cell represents the +sense mode; 1 for edge rising, 2 for edge falling. + +fsl,mpc5200-psc nodes +--------------------- +The PSCs should include a cell-index which is the index of the PSC in +hardware. cell-index is used to determine which shared SoC registers to +use when setting up PSC clocking. cell-index number starts at '0'. ie: + PSC1 has 'cell-index = <0>' + PSC4 has 'cell-index = <3>' + +PSC in i2s mode: The mpc5200 and mpc5200b PSCs are not compatible when in +i2s mode. An 'mpc5200b-psc-i2s' node cannot include 'mpc5200-psc-i2s' in the +compatible field. + + +fsl,mpc5200-gpio and fsl,mpc5200-gpio-wkup nodes +------------------------------------------------ +Each GPIO controller node should have the empty property gpio-controller and +#gpio-cells set to 2. First cell is the GPIO number which is interpreted +according to the bit numbers in the GPIO control registers. The second cell +is for flags which is currently unused. + +fsl,mpc5200-fec nodes +--------------------- +The FEC node can specify one of the following properties to configure +the MII link: +- fsl,7-wire-mode - An empty property that specifies the link uses 7-wire + mode instead of MII +- current-speed - Specifies that the MII should be configured for a fixed + speed. This property should contain two cells. The + first cell specifies the speed in Mbps and the second + should be '0' for half duplex and '1' for full duplex +- phy-handle - Contains a phandle to an Ethernet PHY. + +Interrupt controller (fsl,mpc5200-pic) node +------------------------------------------- +The mpc5200 pic binding splits hardware IRQ numbers into two levels. The +split reflects the layout of the PIC hardware itself, which groups +interrupts into one of three groups; CRIT, MAIN or PERP. Also, the +Bestcomm dma engine has it's own set of interrupt sources which are +cascaded off of peripheral interrupt 0, which the driver interprets as a +fourth group, SDMA. + +The interrupts property for device nodes using the mpc5200 pic consists +of three cells; <L1 L2 level> + + L1 := [CRIT=0, MAIN=1, PERP=2, SDMA=3] + L2 := interrupt number; directly mapped from the value in the + "ICTL PerStat, MainStat, CritStat Encoded Register" + level := [LEVEL_HIGH=0, EDGE_RISING=1, EDGE_FALLING=2, LEVEL_LOW=3] + +For external IRQs, use the following interrupt property values (how to +specify external interrupts is a frequently asked question): +External interrupts: + external irq0: interrupts = <0 0 n>; + external irq1: interrupts = <1 1 n>; + external irq2: interrupts = <1 2 n>; + external irq3: interrupts = <1 3 n>; +'n' is sense (0: level high, 1: edge rising, 2: edge falling 3: level low) + diff --git a/Documentation/powerpc/mpc52xx-device-tree-bindings.txt b/Documentation/powerpc/mpc52xx-device-tree-bindings.txt deleted file mode 100644 index 6f12f1c79c0..00000000000 --- a/Documentation/powerpc/mpc52xx-device-tree-bindings.txt +++ /dev/null @@ -1,277 +0,0 @@ -MPC5200 Device Tree Bindings ----------------------------- - -(c) 2006-2007 Secret Lab Technologies Ltd -Grant Likely <grant.likely at secretlab.ca> - -********** DRAFT *********** -* WARNING: Do not depend on the stability of these bindings just yet. -* The MPC5200 device tree conventions are still in flux -* Keep an eye on the linuxppc-dev mailing list for more details -********** DRAFT *********** - -I - Introduction -================ -Boards supported by the arch/powerpc architecture require device tree be -passed by the boot loader to the kernel at boot time. The device tree -describes what devices are present on the board and how they are -connected. The device tree can either be passed as a binary blob (as -described in Documentation/powerpc/booting-without-of.txt), or passed -by Open Firmware (IEEE 1275) compatible firmware using an OF compatible -client interface API. - -This document specifies the requirements on the device-tree for mpc5200 -based boards. These requirements are above and beyond the details -specified in either the Open Firmware spec or booting-without-of.txt - -All new mpc5200-based boards are expected to match this document. In -cases where this document is not sufficient to support a new board port, -this document should be updated as part of adding the new board support. - -II - Philosophy -=============== -The core of this document is naming convention. The whole point of -defining this convention is to reduce or eliminate the number of -special cases required to support a 5200 board. If all 5200 boards -follow the same convention, then generic 5200 support code will work -rather than coding special cases for each new board. - -This section tries to capture the thought process behind why the naming -convention is what it is. - -1. names ---------- -There is strong convention/requirements already established for children -of the root node. 'cpus' describes the processor cores, 'memory' -describes memory, and 'chosen' provides boot configuration. Other nodes -are added to describe devices attached to the processor local bus. - -Following convention already established with other system-on-chip -processors, 5200 device trees should use the name 'soc5200' for the -parent node of on chip devices, and the root node should be its parent. - -Child nodes are typically named after the configured function. ie. -the FEC node is named 'ethernet', and a PSC in uart mode is named 'serial'. - -2. device_type property ------------------------ -similar to the node name convention above; the device_type reflects the -configured function of a device. ie. 'serial' for a uart and 'spi' for -an spi controller. However, while node names *should* reflect the -configured function, device_type *must* match the configured function -exactly. - -3. compatible property ----------------------- -Since device_type isn't enough to match devices to drivers, there also -needs to be a naming convention for the compatible property. Compatible -is an list of device descriptions sorted from specific to generic. For -the mpc5200, the required format for each compatible value is -<chip>-<device>[-<mode>]. The OS should be able to match a device driver -to the device based solely on the compatible value. If two drivers -match on the compatible list; the 'most compatible' driver should be -selected. - -The split between the MPC5200 and the MPC5200B leaves a bit of a -conundrum. How should the compatible property be set up to provide -maximum compatibility information; but still accurately describe the -chip? For the MPC5200; the answer is easy. Most of the SoC devices -originally appeared on the MPC5200. Since they didn't exist anywhere -else; the 5200 compatible properties will contain only one item; -"mpc5200-<device>". - -The 5200B is almost the same as the 5200, but not quite. It fixes -silicon bugs and it adds a small number of enhancements. Most of the -devices either provide exactly the same interface as on the 5200. A few -devices have extra functions but still have a backwards compatible mode. -To express this information as completely as possible, 5200B device trees -should have two items in the compatible list; -"mpc5200b-<device>\0mpc5200-<device>". It is *strongly* recommended -that 5200B device trees follow this convention (instead of only listing -the base mpc5200 item). - -If another chip appear on the market with one of the mpc5200 SoC -devices, then the compatible list should include mpc5200-<device>. - -ie. ethernet on mpc5200: compatible = "mpc5200-ethernet" - ethernet on mpc5200b: compatible = "mpc5200b-ethernet\0mpc5200-ethernet" - -Modal devices, like PSCs, also append the configured function to the -end of the compatible field. ie. A PSC in i2s mode would specify -"mpc5200-psc-i2s", not "mpc5200-i2s". This convention is chosen to -avoid naming conflicts with non-psc devices providing the same -function. For example, "mpc5200-spi" and "mpc5200-psc-spi" describe -the mpc5200 simple spi device and a PSC spi mode respectively. - -If the soc device is more generic and present on other SOCs, the -compatible property can specify the more generic device type also. - -ie. mscan: compatible = "mpc5200-mscan\0fsl,mscan"; - -At the time of writing, exact chip may be either 'mpc5200' or -'mpc5200b'. - -Device drivers should always try to match as generically as possible. - -III - Structure -=============== -The device tree for an mpc5200 board follows the structure defined in -booting-without-of.txt with the following additional notes: - -0) the root node ----------------- -Typical root description node; see booting-without-of - -1) The cpus node ----------------- -The cpus node follows the basic layout described in booting-without-of. -The bus-frequency property holds the XLB bus frequency -The clock-frequency property holds the core frequency - -2) The memory node ------------------- -Typical memory description node; see booting-without-of. - -3) The soc5200 node -------------------- -This node describes the on chip SOC peripherals. Every mpc5200 based -board will have this node, and as such there is a common naming -convention for SOC devices. - -Required properties: -name type description ----- ---- ----------- -device_type string must be "soc" -ranges int should be <0 baseaddr baseaddr+10000> -reg int must be <baseaddr 10000> -compatible string mpc5200: "mpc5200-soc" - mpc5200b: "mpc5200b-soc\0mpc5200-soc" -system-frequency int Fsystem frequency; source of all - other clocks. -bus-frequency int IPB bus frequency in HZ. Clock rate - used by most of the soc devices. -#interrupt-cells int must be <3>. - -Recommended properties: -name type description ----- ---- ----------- -model string Exact model of the chip; - ie: model="fsl,mpc5200" -revision string Silicon revision of chip - ie: revision="M08A" - -The 'model' and 'revision' properties are *strongly* recommended. Having -them presence acts as a bit of a safety net for working around as yet -undiscovered bugs on one version of silicon. For example, device drivers -can use the model and revision properties to decide if a bug fix should -be turned on. - -4) soc5200 child nodes ----------------------- -Any on chip SOC devices available to Linux must appear as soc5200 child nodes. - -Note: The tables below show the value for the mpc5200. A mpc5200b device -tree should use the "mpc5200b-<device>\0mpc5200-<device> form. - -Required soc5200 child nodes: -name device_type compatible Description ----- ----------- ---------- ----------- -cdm@<addr> cdm mpc5200-cmd Clock Distribution -pic@<addr> interrupt-controller mpc5200-pic need an interrupt - controller to boot -bestcomm@<addr> dma-controller mpc5200-bestcomm 5200 pic also requires - the bestcomm device - -Recommended soc5200 child nodes; populate as needed for your board -name device_type compatible Description ----- ----------- ---------- ----------- -gpt@<addr> gpt fsl,mpc5200-gpt General purpose timers -gpt@<addr> gpt fsl,mpc5200-gpt-gpio General purpose - timers in GPIO mode -gpio@<addr> fsl,mpc5200-gpio MPC5200 simple gpio - controller -gpio@<addr> fsl,mpc5200-gpio-wkup MPC5200 wakeup gpio - controller -rtc@<addr> rtc mpc5200-rtc Real time clock -mscan@<addr> mscan mpc5200-mscan CAN bus controller -pci@<addr> pci mpc5200-pci PCI bridge -serial@<addr> serial mpc5200-psc-uart PSC in serial mode -i2s@<addr> sound mpc5200-psc-i2s PSC in i2s mode -ac97@<addr> sound mpc5200-psc-ac97 PSC in ac97 mode -spi@<addr> spi mpc5200-psc-spi PSC in spi mode -irda@<addr> irda mpc5200-psc-irda PSC in IrDA mode -spi@<addr> spi mpc5200-spi MPC5200 spi device -ethernet@<addr> network mpc5200-fec MPC5200 ethernet device -ata@<addr> ata mpc5200-ata IDE ATA interface -i2c@<addr> i2c mpc5200-i2c I2C controller -usb@<addr> usb-ohci-be mpc5200-ohci,ohci-be USB controller -xlb@<addr> xlb mpc5200-xlb XLB arbitrator - -Important child node properties -name type description ----- ---- ----------- -cell-index int When multiple devices are present, is the - index of the device in the hardware (ie. There - are 6 PSC on the 5200 numbered PSC1 to PSC6) - PSC1 has 'cell-index = <0>' - PSC4 has 'cell-index = <3>' - -5) General Purpose Timer nodes (child of soc5200 node) -On the mpc5200 and 5200b, GPT0 has a watchdog timer function. If the board -design supports the internal wdt, then the device node for GPT0 should -include the empty property 'fsl,has-wdt'. - -6) PSC nodes (child of soc5200 node) -PSC nodes can define the optional 'port-number' property to force assignment -order of serial ports. For example, PSC5 might be physically connected to -the port labeled 'COM1' and PSC1 wired to 'COM1'. In this case, PSC5 would -have a "port-number = <0>" property, and PSC1 would have "port-number = <1>". - -PSC in i2s mode: The mpc5200 and mpc5200b PSCs are not compatible when in -i2s mode. An 'mpc5200b-psc-i2s' node cannot include 'mpc5200-psc-i2s' in the -compatible field. - -7) GPIO controller nodes -Each GPIO controller node should have the empty property gpio-controller and -#gpio-cells set to 2. First cell is the GPIO number which is interpreted -according to the bit numbers in the GPIO control registers. The second cell -is for flags which is currently unsused. - -8) FEC nodes -The FEC node can specify one of the following properties to configure -the MII link: -"fsl,7-wire-mode" - An empty property that specifies the link uses 7-wire - mode instead of MII -"current-speed" - Specifies that the MII should be configured for a fixed - speed. This property should contain two cells. The - first cell specifies the speed in Mbps and the second - should be '0' for half duplex and '1' for full duplex -"phy-handle" - Contains a phandle to an Ethernet PHY. - -IV - Extra Notes -================ - -1. Interrupt mapping --------------------- -The mpc5200 pic driver splits hardware IRQ numbers into two levels. The -split reflects the layout of the PIC hardware itself, which groups -interrupts into one of three groups; CRIT, MAIN or PERP. Also, the -Bestcomm dma engine has it's own set of interrupt sources which are -cascaded off of peripheral interrupt 0, which the driver interprets as a -fourth group, SDMA. - -The interrupts property for device nodes using the mpc5200 pic consists -of three cells; <L1 L2 level> - - L1 := [CRIT=0, MAIN=1, PERP=2, SDMA=3] - L2 := interrupt number; directly mapped from the value in the - "ICTL PerStat, MainStat, CritStat Encoded Register" - level := [LEVEL_HIGH=0, EDGE_RISING=1, EDGE_FALLING=2, LEVEL_LOW=3] - -2. Shared registers -------------------- -Some SoC devices share registers between them. ie. the i2c devices use -a single clock control register, and almost all device are affected by -the port_config register. Devices which need to manipulate shared regs -should look to the parent SoC node. The soc node is responsible -for arbitrating all shared register access. diff --git a/Documentation/video4linux/v4lgrab.c b/Documentation/video4linux/v4lgrab.c index 079b628481c..d6e70bef8ad 100644 --- a/Documentation/video4linux/v4lgrab.c +++ b/Documentation/video4linux/v4lgrab.c @@ -4,12 +4,21 @@ * * Compile with: * gcc -s -Wall -Wstrict-prototypes v4lgrab.c -o v4lgrab - * Use as: - * v4lgrab >image.ppm + * Use as: + * v4lgrab >image.ppm * * Copyright (C) 1998-05-03, Phil Blundell <philb@gnu.org> - * Copied from http://www.tazenda.demon.co.uk/phil/vgrabber.c - * with minor modifications (Dave Forrest, drf5n@virginia.edu). + * Copied from http://www.tazenda.demon.co.uk/phil/vgrabber.c + * with minor modifications (Dave Forrest, drf5n@virginia.edu). + * + * + * For some cameras you may need to pre-load libv4l to perform + * the necessary decompression, e.g.: + * + * export LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so + * ./v4lgrab >image.ppm + * + * see http://hansdegoede.livejournal.com/3636.html for details. * */ @@ -24,7 +33,7 @@ #include <linux/types.h> #include <linux/videodev.h> -#define FILE "/dev/video0" +#define VIDEO_DEV "/dev/video0" /* Stole this from tvset.c */ @@ -90,7 +99,7 @@ int get_brightness_adj(unsigned char *image, long size, int *brightness) { int main(int argc, char ** argv) { - int fd = open(FILE, O_RDONLY), f; + int fd = open(VIDEO_DEV, O_RDONLY), f; struct video_capability cap; struct video_window win; struct video_picture vpic; @@ -100,13 +109,13 @@ int main(int argc, char ** argv) unsigned int i, src_depth; if (fd < 0) { - perror(FILE); + perror(VIDEO_DEV); exit(1); } if (ioctl(fd, VIDIOCGCAP, &cap) < 0) { perror("VIDIOGCAP"); - fprintf(stderr, "(" FILE " not a video4linux device?)\n"); + fprintf(stderr, "(" VIDEO_DEV " not a video4linux device?)\n"); close(fd); exit(1); } |