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raspi document

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...@@ -6,15 +6,20 @@ For V3D 2.x, see brcm,bcm-vc4.txt. ...@@ -6,15 +6,20 @@ For V3D 2.x, see brcm,bcm-vc4.txt.
Required properties: Required properties:
- compatible: Should be "brcm,7268-v3d" or "brcm,7278-v3d" - compatible: Should be "brcm,7268-v3d" or "brcm,7278-v3d"
- reg: Physical base addresses and lengths of the register areas - reg: Physical base addresses and lengths of the register areas
- reg-names: Names for the register areas. The "hub", "bridge", and "core0" - reg-names: Names for the register areas. The "hub" and "core0"
register areas are always required. The "gca" register area register areas are always required. The "gca" register area
is required if the GCA cache controller is present. is required if the GCA cache controller is present. The
"bridge" register area is required if an external reset
controller is not present.
- interrupts: The interrupt numbers. The first interrupt is for the hub, - interrupts: The interrupt numbers. The first interrupt is for the hub,
while the following interrupts are for the cores. while the following interrupts are separate interrupt lines
for the cores (if they don't share the hub's interrupt).
See bindings/interrupt-controller/interrupts.txt See bindings/interrupt-controller/interrupts.txt
Optional properties: Optional properties:
- clocks: The core clock the unit runs on - clocks: The core clock the unit runs on
- resets: The reset line for v3d, if not using a mapping of the bridge
See bindings/reset/reset.txt
v3d { v3d {
compatible = "brcm,7268-v3d"; compatible = "brcm,7268-v3d";
......
Bindings for the Raspberry Pi PoE HAT fan
Required properties:
- compatible : "raspberrypi,rpi-poe-fan"
- firmware : Reference to the RPi firmware device node
- pwms : the PWM that is used to control the PWM fan
- cooling-levels : PWM duty cycle values in a range from 0 to 255
which correspond to thermal cooling states
Example:
fan0: rpi-poe-fan@0 {
compatible = "raspberrypi,rpi-poe-fan";
firmware = <&firmware>;
cooling-min-state = <0>;
cooling-max-state = <3>;
#cooling-cells = <2>;
cooling-levels = <0 50 150 255>;
status = "okay";
};
thermal-zones {
cpu_thermal: cpu-thermal {
trips {
threshold: trip-point@0 {
temperature = <45000>;
hysteresis = <5000>;
type = "active";
};
target: trip-point@1 {
temperature = <50000>;
hysteresis = <2000>;
type = "active";
};
cpu_hot: cpu_hot@0 {
temperature = <55000>;
hysteresis = <2000>;
type = "active";
};
};
cooling-maps {
map0 {
trip = <&threshold>;
cooling-device = <&fan0 0 1>;
};
map1 {
trip = <&target>;
cooling-device = <&fan0 1 2>;
};
map2 {
trip = <&cpu_hot>;
cooling-device = <&fan0 2 3>;
};
};
};
};
Ilitek ILI210x/ILI251x touchscreen controller
Required properties:
- compatible:
ilitek,ili210x for ILI210x
ilitek,ili251x for ILI251x
- reg: The I2C address of the device
- interrupts: The sink for the touchscreen's IRQ output
See ../interrupt-controller/interrupts.txt
Optional properties for main touchpad device:
- reset-gpios: GPIO specifier for the touchscreen's reset pin (active low)
Example:
touchscreen@41 {
compatible = "ilitek,ili251x";
reg = <0x41>;
interrupt-parent = <&gpio4>;
interrupts = <7 IRQ_TYPE_EDGE_FALLING>;
reset-gpios = <&gpio5 21 GPIO_ACTIVE_LOW>;
};
Broadcom BCM283x Camera Interface (Unicam)
------------------------------------------
The Unicam block on BCM283x SoCs is the receiver for either
CSI-2 or CCP2 data from image sensors or similar devices.
The main platform using this SoC is the Raspberry Pi family of boards.
On the Pi the VideoCore firmware can also control this hardware block,
and driving it from two different processors will cause issues.
To avoid this, the firmware checks the device tree configuration
during boot. If it finds device tree nodes called csi0 or csi1 then
it will stop the firmware accessing the block, and it can then
safely be used via the device tree binding.
Required properties:
===================
- compatible : must be "brcm,bcm2835-unicam".
- reg : physical base address and length of the register sets for the
device.
- interrupts : should contain the IRQ line for this Unicam instance.
- clocks : list of clock specifiers, corresponding to entries in
clock-names property.
- clock-names : must contain an "lp" entry, matching entries in the
clocks property.
Unicam supports a single port node. It should contain one 'port' child node
with child 'endpoint' node. Please refer to the bindings defined in
Documentation/devicetree/bindings/media/video-interfaces.txt.
Within the endpoint node the "remote-endpoint" and "data-lanes" properties
are mandatory.
Data lane reordering is not supported so the data lanes must be in order,
starting at 1. The number of data lanes should represent the number of
usable lanes for the hardware block. That may be limited by either the SoC or
how the platform presents the interface, and the lower value must be used.
Lane reordering is not supported on the clock lane either, so the optional
property "clock-lane" will implicitly be <0>.
Similarly lane inversion is not supported, therefore "lane-polarities" will
implicitly be <0 0 0 0 0>.
Neither of these values will be checked.
Example:
csi1: csi1@7e801000 {
compatible = "brcm,bcm2835-unicam";
reg = <0x7e801000 0x800>,
<0x7e802004 0x4>;
interrupts = <2 7>;
clocks = <&clocks BCM2835_CLOCK_CAM1>;
clock-names = "lp";
port {
csi1_ep: endpoint {
remote-endpoint = <&tc358743_0>;
data-lanes = <1 2>;
};
};
};
i2c0: i2c@7e205000 {
tc358743: csi-hdmi-bridge@0f {
compatible = "toshiba,tc358743";
reg = <0x0f>;
clocks = <&tc358743_clk>;
clock-names = "refclk";
tc358743_clk: bridge-clk {
compatible = "fixed-clock";
#clock-cells = <0>;
clock-frequency = <27000000>;
};
port {
tc358743_0: endpoint {
remote-endpoint = <&csi1_ep>;
clock-lanes = <0>;
data-lanes = <1 2>;
clock-noncontinuous;
link-frequencies =
/bits/ 64 <297000000>;
};
};
};
};
* Sony 1/4.0-Inch 8Mpixel CMOS Digital Image Sensor
The Sony imx219 is a 1/4.0-inch CMOS active pixel digital image sensor with
an active array size of 3280H x 2464V. It is programmable through I2C
interface. The I2C address is fixed to 0x10 as per sensor data sheet.
Image data is sent through MIPI CSI-2, which is configured as either 2 or 4
data lanes.
Required Properties:
- compatible: value should be "sony,imx219" for imx219 sensor
- reg: I2C bus address of the device
- clocks: reference to the xclk input clock.
- clock-names: should be "xclk".
- DOVDD-supply: Digital I/O voltage supply, 1.8 volts
- AVDD-supply: Analog voltage supply, 2.8 volts
- DVDD-supply: Digital core voltage supply, 1.2 volts
Optional Properties:
- xclr-gpios: reference to the GPIO connected to the xclr pin, if any. Must be
released after all supplies are applied.
This is an active high signal to the imx219.
The imx219 device node should contain one 'port' child node with
an 'endpoint' subnode. For further reading on port node refer to
Documentation/devicetree/bindings/media/video-interfaces.txt.
Endpoint node required properties for CSI-2 connection are:
- remote-endpoint: a phandle to the bus receiver's endpoint node.
- clock-lanes: should be set to <0> (clock lane on hardware lane 0)
- data-lanes: should be set to <1 2>, or <1 2 3 4> (two or four lane CSI-2
supported)
Example:
sensor@10 {
compatible = "sony,imx219";
reg = <0x10>;
#address-cells = <1>;
#size-cells = <0>;
clocks = <&imx219_clk>;
clock-names = "xclk";
xclr-gpios = <&gpio_sensor 0 0>;
DOVDD-supply = <&vgen4_reg>; /* 1.8v */
AVDD-supply = <&vgen3_reg>; /* 2.8v */
DVDD-supply = <&vgen2_reg>; /* 1.2v */
imx219_clk: camera-clk {
compatible = "fixed-clock";
#clock-cells = <0>;
clock-frequency = <24000000>;
};
port {
sensor_out: endpoint {
remote-endpoint = <&csiss_in>;
clock-lanes = <0>;
data-lanes = <1 2>;
};
};
};
* Infineon irs1125 time of flight sensor
The Infineon irs1125 is a time of flight digital image sensor with
an active array size of 352H x 286V. It is programmable through I2C
interface. The I2C address defaults to 0x3D, but can be reconfigured
to address 0x3C or 0x41 via I2C commands. Image data is sent through
MIPI CSI-2, which is configured as either 1 or 2 data lanes.
Required Properties:
- compatible: value should be "infineon,irs1125" for irs1125 sensor
- reg: I2C bus address of the device
- clocks: reference to the xclk input clock.
- pwdn-gpios: reference to the GPIO connected to the reset pin.
This is an active low signal to the iirs1125.
The irs1125 device node should contain one 'port' child node with
an 'endpoint' subnode. For further reading on port node refer to
Documentation/devicetree/bindings/media/video-interfaces.txt.
Endpoint node required properties for CSI-2 connection are:
- remote-endpoint: a phandle to the bus receiver's endpoint node.
- clock-lanes: should be set to <0> (clock lane on hardware lane 0)
- data-lanes: should be set to <1> or <1 2> (one or two lane CSI-2
supported)
Example:
sensor@10 {
compatible = "infineon,irs1125";
reg = <0x3D>;
#address-cells = <1>;
#size-cells = <0>;
clocks = <&irs1125_clk>;
pwdn-gpios = <&gpio 5 0>;
irs1125_clk: camera-clk {
compatible = "fixed-clock";
#clock-cells = <0>;
clock-frequency = <26000000>;
};
port {
sensor_out: endpoint {
remote-endpoint = <&csiss_in>;
clock-lanes = <0>;
data-lanes = <1 2>;
};
};
};
...@@ -10,6 +10,9 @@ Required properties: ...@@ -10,6 +10,9 @@ Required properties:
- reg : I2C slave address of the sensor. - reg : I2C slave address of the sensor.
- clocks : Reference to the xclk clock. - clocks : Reference to the xclk clock.
Optional Properties:
- pwdn-gpios: reference to the GPIO connected to the pwdn pin, if any.
The common video interfaces bindings (see video-interfaces.txt) should be The common video interfaces bindings (see video-interfaces.txt) should be
used to specify link to the image data receiver. The OV5647 device used to specify link to the image data receiver. The OV5647 device
node should contain one 'port' child node with an 'endpoint' subnode. node should contain one 'port' child node with an 'endpoint' subnode.
...@@ -26,6 +29,7 @@ Example: ...@@ -26,6 +29,7 @@ Example:
compatible = "ovti,ov5647"; compatible = "ovti,ov5647";
reg = <0x36>; reg = <0x36>;
clocks = <&camera_clk>; clocks = <&camera_clk>;
pwdn-gpios = <&pioE 29 GPIO_ACTIVE_HIGH>;
port { port {
camera_1: endpoint { camera_1: endpoint {
remote-endpoint = <&csi1_ep1>; remote-endpoint = <&csi1_ep1>;
......
* Broadcom BCM2835 SMI character device driver.
SMI or secondary memory interface is a peripheral specific to certain Broadcom
SOCs, and is helpful for talking to things like parallel-interface displays
and NAND flashes (in fact, most things with a parallel register interface).
This driver adds a character device which provides a user-space interface to
an instance of the SMI driver.
Required properties:
- compatible: "brcm,bcm2835-smi-dev"
- smi_handle: a phandle to the smi node.
Optional properties:
- None.
* Broadcom BCM2835 SMI driver.
SMI or secondary memory interface is a peripheral specific to certain Broadcom
SOCs, and is helpful for talking to things like parallel-interface displays
and NAND flashes (in fact, most things with a parallel register interface).
Required properties:
- compatible: "brcm,bcm2835-smi"
- reg: Should contain location and length of SMI registers and SMI clkman regs
- interrupts: *the* SMI interrupt.
- pinctrl-names: should be "default".
- pinctrl-0: the phandle of the gpio pin node.
- brcm,smi-clock-source: the clock source for clkman
- brcm,smi-clock-divisor: the integer clock divisor for clkman
- dmas: the dma controller phandle and the DREQ number (4 on a 2835)
- dma-names: the name used by the driver to request its channel.
Should be "rx-tx".
Optional properties:
- None.
Examples:
8 data pin configuration:
smi: smi@7e600000 {
compatible = "brcm,bcm2835-smi";
reg = <0x7e600000 0x44>, <0x7e1010b0 0x8>;
interrupts = <2 16>;
pinctrl-names = "default";
pinctrl-0 = <&smi_pins>;
brcm,smi-clock-source = <6>;
brcm,smi-clock-divisor = <4>;
dmas = <&dma 4>;
dma-names = "rx-tx";
status = "okay";
};
smi_pins: smi_pins {
brcm,pins = <2 3 4 5 6 7 8 9 10 11 12 13 14 15>;
/* Alt 1: SMI */
brcm,function = <5 5 5 5 5 5 5 5 5 5 5 5 5 5>;
/* /CS, /WE and /OE are pulled high, as they are
generally active low signals */
brcm,pull = <2 2 2 2 2 2 0 0 0 0 0 0 0 0>;
};
* BCM2835 SMI NAND flash
This driver is a shim between the BCM2835 SMI driver (SMI is a peripheral for
talking to parallel register interfaces) and Linux's MTD layer.
Required properties:
- compatible: "brcm,bcm2835-smi-nand"
- status: "okay"
Optional properties:
- partition@n, where n is an integer from a consecutive sequence starting at 0
- Difficult to store partition table on NAND device - normally put it
in the source code, kernel bootparams, or device tree (the best way!)
- Sub-properties:
- label: the partition name, as shown by mtdinfo /dev/mtd*
- reg: the size and offset of this partition.
- (optional) read-only: an empty property flagging as read only
Example:
nand: flash@0 {
compatible = "brcm,bcm2835-smi-nand";
status = "okay";
partition@0 {
label = "stage2";
// 128k
reg = <0 0x20000>;
read-only;
};
partition@1 {
label = "firmware";
// 16M
reg = <0x20000 0x1000000>;
read-only;
};
partition@2 {
label = "root";
// 2G
reg = <0x1020000 0x80000000>;
};
};
\ No newline at end of file
...@@ -15,6 +15,9 @@ Optional properties of the embedded PHY: ...@@ -15,6 +15,9 @@ Optional properties of the embedded PHY:
- microchip,led-modes: a 0..4 element vector, with each element configuring - microchip,led-modes: a 0..4 element vector, with each element configuring
the operating mode of an LED. Omitted LEDs are turned off. Allowed values the operating mode of an LED. Omitted LEDs are turned off. Allowed values
are defined in "include/dt-bindings/net/microchip-lan78xx.h". are defined in "include/dt-bindings/net/microchip-lan78xx.h".
- microchip,downshift-after: sets the number of failed auto-negotiation
attempts after which the link is downgraded from 1000BASE-T. Should be one of
2, 3, 4, 5 or 0, where 0 means never downshift.
Example: Example:
......
Brcmstb PCIe Host Controller Device Tree Bindings
Required Properties:
- compatible
"brcm,bcm7425-pcie" -- for 7425 family MIPS-based SOCs.
"brcm,bcm7435-pcie" -- for 7435 family MIPS-based SOCs.
"brcm,bcm7445-pcie" -- for 7445 and later ARM based SOCs (not including
the 7278).
"brcm,bcm7278-pcie" -- for 7278 family ARM-based SOCs.
- reg -- the register start address and length for the PCIe reg block.
- interrupts -- two interrupts are specified; the first interrupt is for
the PCI host controller and the second is for MSI if the built-in
MSI controller is to be used.
- interrupt-names -- names of the interrupts (above): "pcie" and "msi".
- #address-cells -- set to <3>.
- #size-cells -- set to <2>.
- #interrupt-cells: set to <1>.
- interrupt-map-mask and interrupt-map, standard PCI properties to define the
mapping of the PCIe interface to interrupt numbers.
- ranges: ranges for the PCI memory and I/O regions.
- linux,pci-domain -- should be unique per host controller.
Optional Properties:
- clocks -- phandle of pcie clock.
- clock-names -- set to "sw_pcie" if clocks is used.
- dma-ranges -- Specifies the inbound memory mapping regions when
an "identity map" is not possible.
- msi-controller -- this property is typically specified to have the
PCIe controller use its internal MSI controller.
- msi-parent -- set to use an external MSI interrupt controller.
- brcm,enable-ssc -- (boolean) indicates usage of spread-spectrum clocking.
- max-link-speed -- (integer) indicates desired generation of link:
1 => 2.5 Gbps (gen1), 2 => 5.0 Gbps (gen2), 3 => 8.0 Gbps (gen3).
Example Node:
pcie0: pcie@f0460000 {
reg = <0x0 0xf0460000 0x0 0x9310>;
interrupts = <0x0 0x0 0x4>;
compatible = "brcm,bcm7445-pcie";
#address-cells = <3>;
#size-cells = <2>;
ranges = <0x02000000 0x00000000 0x00000000 0x00000000 0xc0000000 0x00000000 0x08000000
0x02000000 0x00000000 0x08000000 0x00000000 0xc8000000 0x00000000 0x08000000>;
#interrupt-cells = <1>;
interrupt-map-mask = <0 0 0 7>;
interrupt-map = <0 0 0 1 &intc 0 47 3
0 0 0 2 &intc 0 48 3
0 0 0 3 &intc 0 49 3
0 0 0 4 &intc 0 50 3>;
clocks = <&sw_pcie0>;
clock-names = "sw_pcie";
msi-parent = <&pcie0>; /* use PCIe's internal MSI controller */
msi-controller; /* use PCIe's internal MSI controller */
brcm,ssc;
max-link-speed = <1>;
linux,pci-domain = <0>;
};
...@@ -29,6 +29,7 @@ Optional properties: ...@@ -29,6 +29,7 @@ Optional properties:
inactive state. inactive state.
- timeout-ms: Time to wait before asserting a WARN_ON(1). If nothing is - timeout-ms: Time to wait before asserting a WARN_ON(1). If nothing is
specified, 3000 ms is used. specified, 3000 ms is used.
- export : Export the GPIO line to the sysfs system
Examples: Examples:
......
Generic device tree bindings for Real Time Clock devices
========================================================
This document describes generic bindings which can be used to describe Real Time
Clock devices in a device tree.
Required properties
-------------------
- compatible : name of RTC device following generic names recommended practice.
For other required properties e.g. to describe register sets,
clocks, etc. check the binding documentation of the specific driver.
Optional properties
-------------------
- start-year : if provided, the default hardware range supported by the RTC is
shifted so the first usable year is the specified one.
The following properties may not be supported by all drivers. However, if a
driver wants to support one of the below features, it should adapt the bindings
below.
- trickle-resistor-ohms : Selected resistor for trickle charger. Should be given
if trickle charger should be enabled
- trickle-diode-disable : Do not use internal trickle charger diode Should be
given if internal trickle charger diode should be
disabled
- backup-switchover-mode : Configure RTC backup power supply switch behaviour
- wakeup-source : Enables wake up of host system on alarm
- quartz-load-femtofarads : The capacitive load of the quartz(x-tal),
expressed in femto Farad (fF).
The default value shall be listed (if optional),
and likewise all valid values.
Trivial RTCs
------------
This is a list of trivial RTC devices that have simple device tree
bindings, consisting only of a compatible field, an address and
possibly an interrupt line.
Compatible Vendor / Chip
========== =============
abracon,abb5zes3 AB-RTCMC-32.768kHz-B5ZE-S3: Real Time Clock/Calendar Module with I2C Interface
dallas,ds1374 I2C, 32-Bit Binary Counter Watchdog RTC with Trickle Charger and Reset Input/Output
dallas,ds1672 Dallas DS1672 Real-time Clock
dallas,ds3232 Extremely Accurate I²C RTC with Integrated Crystal and SRAM
epson,rx8010 I2C-BUS INTERFACE REAL TIME CLOCK MODULE
epson,rx8581 I2C-BUS INTERFACE REAL TIME CLOCK MODULE
emmicro,em3027 EM Microelectronic EM3027 Real-time Clock
isil,isl1208 Intersil ISL1208 Low Power RTC with Battery Backed SRAM
isil,isl1218 Intersil ISL1218 Low Power RTC with Battery Backed SRAM
isil,isl12022 Intersil ISL12022 Real-time Clock
microcrystal,rv3028 Real Time Clock Module with I2C-Bus
microcrystal,rv3029 Real Time Clock Module with I2C-Bus
microcrystal,rv8523 Real Time Clock
nxp,pcf2127 Real-time clock
nxp,pcf2129 Real-time clock
nxp,pcf8563 Real-time clock/calendar
pericom,pt7c4338 Real-time Clock Module
ricoh,r2025sd I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
ricoh,r2221tl I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
ricoh,rs5c372a I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
ricoh,rs5c372b I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
ricoh,rv5c386 I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
ricoh,rv5c387a I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
sii,s35390a 2-wire CMOS real-time clock
whwave,sd3078 I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
...@@ -35,6 +35,9 @@ Optional properties: ...@@ -35,6 +35,9 @@ Optional properties:
- poll-timeout-ms: - poll-timeout-ms:
Poll timeout when auto-poll is set, default Poll timeout when auto-poll is set, default
3000ms. 3000ms.
- cts-event-workaround:
Enables the (otherwise vendor-specific) workaround for the
CTS-induced TX lockup.
See also bindings/arm/primecell.txt See also bindings/arm/primecell.txt
......
...@@ -56,6 +56,7 @@ axis Axis Communications AB ...@@ -56,6 +56,7 @@ axis Axis Communications AB
bananapi BIPAI KEJI LIMITED bananapi BIPAI KEJI LIMITED
bhf Beckhoff Automation GmbH & Co. KG bhf Beckhoff Automation GmbH & Co. KG
bitmain Bitmain Technologies bitmain Bitmain Technologies
blokaslabs Vilniaus Blokas UAB
boe BOE Technology Group Co., Ltd. boe BOE Technology Group Co., Ltd.
bosch Bosch Sensortec GmbH bosch Bosch Sensortec GmbH
boundary Boundary Devices Inc. boundary Boundary Devices Inc.
......
Howto use the configfs overlay interface.
A device-tree configfs entry is created in /config/device-tree/overlays
and and it is manipulated using standard file system I/O.
Note that this is a debug level interface, for use by developers and
not necessarily something accessed by normal users due to the
security implications of having direct access to the kernel's device tree.
* To create an overlay you mkdir the directory:
# mkdir /config/device-tree/overlays/foo
* Either you echo the overlay firmware file to the path property file.
# echo foo.dtbo >/config/device-tree/overlays/foo/path
* Or you cat the contents of the overlay to the dtbo file
# cat foo.dtbo >/config/device-tree/overlays/foo/dtbo
The overlay file will be applied, and devices will be created/destroyed
as required.
To remove it simply rmdir the directory.
# rmdir /config/device-tree/overlays/foo
The rationalle of the dual interface (firmware & direct copy) is that each is
better suited to different use patterns. The firmware interface is what's
intended to be used by hardware managers in the kernel, while the copy interface
make sense for developers (since it avoids problems with namespaces).
...@@ -51,6 +51,20 @@ To force the VGA output to be enabled and drive a specific mode say: ...@@ -51,6 +51,20 @@ To force the VGA output to be enabled and drive a specific mode say:
Specifying the option multiple times for different ports is possible, e.g.: Specifying the option multiple times for different ports is possible, e.g.:
video=LVDS-1:d video=HDMI-1:D video=LVDS-1:d video=HDMI-1:D
Options can also be passed after the mode, using commas as separator.
Sample usage: 720x480,rotate=180 - 720x480 mode, rotated by 180 degrees
Valid options are:
- margin_top, margin_bottom, margin_left, margin_right (integer):
Number of pixels in the margins, typically to deal with overscan on TVs
- reflect_x (boolean): Perform an axial symmetry on the X axis
- reflect_y (boolean): Perform an axial symmetry on the Y axis
- rotate (integer): Rotate the initial framebuffer by x
degrees. Valid values are 0, 90, 180 and 270.
***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo *****
What is the VESA(TM) Coordinated Video Timings (CVT)? What is the VESA(TM) Coordinated Video Timings (CVT)?
......
Kernel driver rpi-poe-fan
=====================
This driver enables the use of the Raspberry Pi PoE HAT fan.
Author: Serge Schneider <serge@raspberrypi.org>
Description
-----------
The driver implements a simple interface for driving the Raspberry Pi PoE
(Power over Ethernet) HAT fan. The driver passes commands to the Raspberry Pi
firmware through the mailbox property interface. The firmware then forwards
the commands to the board over I2C on the ID_EEPROM pins. The driver exposes
the fan to the user space through the hwmon sysfs interface.
...@@ -102,7 +102,19 @@ than the number requested. ...@@ -102,7 +102,19 @@ than the number requested.
- ``format`` - ``format``
- Filled in by the application, preserved by the driver. - Filled in by the application, preserved by the driver.
* - __u32 * - __u32
- ``reserved``\ [8] - ``capabilities``
- Set by the driver. If 0, then the driver doesn't support
capabilities. In that case all you know is that the driver is
guaranteed to support ``V4L2_MEMORY_MMAP`` and *might* support
other :c:type:`v4l2_memory` types. It will not support any others
capabilities. See :ref:`here <v4l2-buf-capabilities>` for a list of the
capabilities.
If you want to just query the capabilities without making any
other changes, then set ``count`` to 0, ``memory`` to
``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type.
* - __u32
- ``reserved``\ [7]
- A place holder for future extensions. Drivers and applications - A place holder for future extensions. Drivers and applications
must set the array to zero. must set the array to zero.
......
...@@ -59,9 +59,14 @@ When the I/O method is not supported the ioctl returns an ``EINVAL`` error ...@@ -59,9 +59,14 @@ When the I/O method is not supported the ioctl returns an ``EINVAL`` error
code. code.
Applications can call :ref:`VIDIOC_REQBUFS` again to change the number of Applications can call :ref:`VIDIOC_REQBUFS` again to change the number of
buffers, however this cannot succeed when any buffers are still mapped. buffers. Note that if any buffers are still mapped or exported via DMABUF,
A ``count`` value of zero frees all buffers, after aborting or finishing then :ref:`VIDIOC_REQBUFS` can only succeed if the
any DMA in progress, an implicit ``V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS`` capability is set. Otherwise
:ref:`VIDIOC_REQBUFS` will return the ``EBUSY`` error code.
If ``V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS`` is set, then these buffers are
orphaned and will be freed when they are unmapped or when the exported DMABUF
fds are closed. A ``count`` value of zero frees or orphans all buffers, after
aborting or finishing any DMA in progress, an implicit
:ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>`. :ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>`.
...@@ -88,10 +93,56 @@ any DMA in progress, an implicit ...@@ -88,10 +93,56 @@ any DMA in progress, an implicit
``V4L2_MEMORY_DMABUF`` or ``V4L2_MEMORY_USERPTR``. See ``V4L2_MEMORY_DMABUF`` or ``V4L2_MEMORY_USERPTR``. See
:c:type:`v4l2_memory`. :c:type:`v4l2_memory`.
* - __u32 * - __u32
- ``reserved``\ [2] - ``capabilities``
- Set by the driver. If 0, then the driver doesn't support
capabilities. In that case all you know is that the driver is
guaranteed to support ``V4L2_MEMORY_MMAP`` and *might* support
other :c:type:`v4l2_memory` types. It will not support any others
capabilities.
If you want to query the capabilities with a minimum of side-effects,
then this can be called with ``count`` set to 0, ``memory`` set to
``V4L2_MEMORY_MMAP`` and ``type`` set to the buffer type. This will
free any previously allocated buffers, so this is typically something
that will be done at the start of the application.
* - __u32
- ``reserved``\ [1]
- A place holder for future extensions. Drivers and applications - A place holder for future extensions. Drivers and applications
must set the array to zero. must set the array to zero.
.. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}|
.. _v4l2-buf-capabilities:
.. _V4L2-BUF-CAP-SUPPORTS-MMAP:
.. _V4L2-BUF-CAP-SUPPORTS-USERPTR:
.. _V4L2-BUF-CAP-SUPPORTS-DMABUF:
.. _V4L2-BUF-CAP-SUPPORTS-REQUESTS:
.. _V4L2-BUF-CAP-SUPPORTS-ORPHANED-BUFS:
.. cssclass:: longtable
.. flat-table:: V4L2 Buffer Capabilities Flags
:header-rows: 0
:stub-columns: 0
:widths: 3 1 4
* - ``V4L2_BUF_CAP_SUPPORTS_MMAP``
- 0x00000001
- This buffer type supports the ``V4L2_MEMORY_MMAP`` streaming mode.
* - ``V4L2_BUF_CAP_SUPPORTS_USERPTR``
- 0x00000002
- This buffer type supports the ``V4L2_MEMORY_USERPTR`` streaming mode.
* - ``V4L2_BUF_CAP_SUPPORTS_DMABUF``
- 0x00000004
- This buffer type supports the ``V4L2_MEMORY_DMABUF`` streaming mode.
* - ``V4L2_BUF_CAP_SUPPORTS_REQUESTS``
- 0x00000008
- This buffer type supports :ref:`requests <media-request-api>`.
* - ``V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS``
- 0x00000010
- The kernel allows calling :ref:`VIDIOC_REQBUFS` while buffers are still
mapped or exported via DMABUF. These orphaned buffers will be freed
when they are unmapped or when the exported DMABUF fds are closed.
Return Value Return Value
============ ============
......
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