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-rw-r--r--Documentation/driver-api/ipmi.rst64
-rw-r--r--Documentation/driver-api/media/drivers/rkisp1.rst43
-rw-r--r--Documentation/driver-api/media/maintainer-entry-profile.rst2
-rw-r--r--Documentation/driver-api/media/v4l2-subdev.rst14
-rw-r--r--Documentation/driver-api/mmc/mmc-tools.rst4
-rw-r--r--Documentation/driver-api/thermal/sysfs-api.rst225
6 files changed, 118 insertions, 234 deletions
diff --git a/Documentation/driver-api/ipmi.rst b/Documentation/driver-api/ipmi.rst
index bc281f10ce4b..e224e47b6b09 100644
--- a/Documentation/driver-api/ipmi.rst
+++ b/Documentation/driver-api/ipmi.rst
@@ -166,8 +166,8 @@ and the type is IPMI_SYSTEM_INTERFACE_ADDR_TYPE. This is used for talking
straight to the BMC on the current card. The channel must be
IPMI_BMC_CHANNEL.
-Messages that are destined to go out on the IPMB bus use the
-IPMI_IPMB_ADDR_TYPE address type. The format is::
+Messages that are destined to go out on the IPMB bus going through the
+BMC use the IPMI_IPMB_ADDR_TYPE address type. The format is::
struct ipmi_ipmb_addr
{
@@ -181,6 +181,23 @@ The "channel" here is generally zero, but some devices support more
than one channel, it corresponds to the channel as defined in the IPMI
spec.
+There is also an IPMB direct address for a situation where the sender
+is directly on an IPMB bus and doesn't have to go through the BMC.
+You can send messages to a specific management controller (MC) on the
+IPMB using the IPMI_IPMB_DIRECT_ADDR_TYPE with the following format::
+
+ struct ipmi_ipmb_direct_addr
+ {
+ int addr_type;
+ short channel;
+ unsigned char slave_addr;
+ unsigned char rq_lun;
+ unsigned char rs_lun;
+ };
+
+The channel is always zero. You can also receive commands from other
+MCs that you have registered to handle and respond to them, so you can
+use this to implement a management controller on a bus..
Messages
--------
@@ -348,6 +365,10 @@ user may be registered for each netfn/cmd/channel, but different users
may register for different commands, or the same command if the
channel bitmasks do not overlap.
+To respond to a received command, set the response bit in the returned
+netfn, use the address from the received message, and use the same
+msgid that you got in the receive message.
+
From userland, equivalent IOCTLs are provided to do these functions.
@@ -570,6 +591,45 @@ web page.
The driver supports a hot add and remove of interfaces through the I2C
sysfs interface.
+The IPMI IPMB Driver
+--------------------
+
+This driver is for supporting a system that sits on an IPMB bus; it
+allows the interface to look like a normal IPMI interface. Sending
+system interface addressed messages to it will cause the message to go
+to the registered BMC on the system (default at IPMI address 0x20).
+
+It also allows you to directly address other MCs on the bus using the
+ipmb direct addressing. You can receive commands from other MCs on
+the bus and they will be handled through the normal received command
+mechanism described above.
+
+Parameters are::
+
+ ipmi_ipmb.bmcaddr=<address to use for system interface addresses messages>
+ ipmi_ipmb.retry_time_ms=<Time between retries on IPMB>
+ ipmi_ipmb.max_retries=<Number of times to retry a message>
+
+Loading the module will not result in the driver automatcially
+starting unless there is device tree information setting it up. If
+you want to instantiate one of these by hand, do::
+
+ echo ipmi-ipmb <addr> > /sys/class/i2c-dev/i2c-<n>/device/new_device
+
+Note that the address you give here is the I2C address, not the IPMI
+address. So if you want your MC address to be 0x60, you put 0x30
+here. See the I2C driver info for more details.
+
+Command bridging to other IPMB busses through this interface does not
+work. The receive message queue is not implemented, by design. There
+is only one receive message queue on a BMC, and that is meant for the
+host drivers, not something on the IPMB bus.
+
+A BMC may have multiple IPMB busses, which bus your device sits on
+depends on how the system is wired. You can fetch the channels with
+"ipmitool channel info <n>" where <n> is the channel, with the
+channels being 0-7 and try the IPMB channels.
+
Other Pieces
------------
diff --git a/Documentation/driver-api/media/drivers/rkisp1.rst b/Documentation/driver-api/media/drivers/rkisp1.rst
new file mode 100644
index 000000000000..ea336958a3af
--- /dev/null
+++ b/Documentation/driver-api/media/drivers/rkisp1.rst
@@ -0,0 +1,43 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+The Rockchip Image Signal Processor Driver (rkisp1)
+===================================================
+
+Versions and their differences
+------------------------------
+
+The rkisp1 block underwent some changes between SoC implementations.
+The vendor designates them as:
+
+- V10: used at least in rk3288 and rk3399
+- V11: declared in the original vendor code, but not used
+- V12: used at least in rk3326 and px30
+- V13: used at least in rk1808
+- V20: used in rk3568 and beyond
+
+Right now the kernel supports rkisp1 implementations based
+on V10 and V12 variants. V11 does not seem to be actually used
+and V13 will need some more additions but isn't researched yet,
+especially as it seems to be limited to the rk1808 which hasn't
+reached much market spread.
+
+V20 on the other hand will probably be used in future SoCs and
+has seen really big changes in the vendor kernel, so will need
+quite a bit of research.
+
+Changes from V10 to V12
+-----------------------
+
+- V12 supports a new CSI-host implementation but can still
+ also use the same implementation from V10
+- The module for lens shading correction got changed
+ from 12bit to 13bit width
+- The AWB and AEC modules got replaced to support finer
+ grained data collection
+
+Changes from V12 to V13
+-----------------------
+
+The list for V13 is incomplete and needs further investigation.
+
+- V13 does not support the old CSI-host implementation anymore
diff --git a/Documentation/driver-api/media/maintainer-entry-profile.rst b/Documentation/driver-api/media/maintainer-entry-profile.rst
index eb1cdfd280ba..ffc712a5f632 100644
--- a/Documentation/driver-api/media/maintainer-entry-profile.rst
+++ b/Documentation/driver-api/media/maintainer-entry-profile.rst
@@ -71,7 +71,7 @@ media maintainers do the review.
The media maintainers that work on specific areas of the subsystem are:
-- Digital TV and remote controllers:
+- Remote Controllers (infrared):
Sean Young <sean@mess.org>
- HDMI CEC:
diff --git a/Documentation/driver-api/media/v4l2-subdev.rst b/Documentation/driver-api/media/v4l2-subdev.rst
index 7736da077fb8..08ea2673b19e 100644
--- a/Documentation/driver-api/media/v4l2-subdev.rst
+++ b/Documentation/driver-api/media/v4l2-subdev.rst
@@ -191,21 +191,21 @@ registered this way are stored in a global list of subdevices, ready to be
picked up by bridge drivers.
Bridge drivers in turn have to register a notifier object. This is
-performed using the :c:func:`v4l2_async_notifier_register` call. To
+performed using the :c:func:`v4l2_async_nf_register` call. To
unregister the notifier the driver has to call
-:c:func:`v4l2_async_notifier_unregister`. The former of the two functions
+:c:func:`v4l2_async_nf_unregister`. The former of the two functions
takes two arguments: a pointer to struct :c:type:`v4l2_device` and a
pointer to struct :c:type:`v4l2_async_notifier`.
Before registering the notifier, bridge drivers must do two things: first, the
-notifier must be initialized using the :c:func:`v4l2_async_notifier_init`.
+notifier must be initialized using the :c:func:`v4l2_async_nf_init`.
Second, bridge drivers can then begin to form a list of subdevice descriptors
that the bridge device needs for its operation. Several functions are available
to add subdevice descriptors to a notifier, depending on the type of device and
the needs of the driver.
-:c:func:`v4l2_async_notifier_add_fwnode_remote_subdev` and
-:c:func:`v4l2_async_notifier_add_i2c_subdev` are for bridge and ISP drivers for
+:c:func:`v4l2_async_nf_add_fwnode_remote` and
+:c:func:`v4l2_async_nf_add_i2c` are for bridge and ISP drivers for
registering their async sub-devices with the notifier.
:c:func:`v4l2_async_register_subdev_sensor` is a helper function for
@@ -230,8 +230,8 @@ These functions allocate an async sub-device descriptor which is of type struct
...
- my_asd = v4l2_async_notifier_add_fwnode_remote_subdev(&notifier, ep,
- struct my_async_subdev);
+ my_asd = v4l2_async_nf_add_fwnode_remote(&notifier, ep,
+ struct my_async_subdev);
fwnode_handle_put(ep);
if (IS_ERR(asd))
diff --git a/Documentation/driver-api/mmc/mmc-tools.rst b/Documentation/driver-api/mmc/mmc-tools.rst
index a231e9644351..eee1c2ccfa8f 100644
--- a/Documentation/driver-api/mmc/mmc-tools.rst
+++ b/Documentation/driver-api/mmc/mmc-tools.rst
@@ -2,10 +2,10 @@
MMC tools introduction
======================
-There is one MMC test tools called mmc-utils, which is maintained by Chris Ball,
+There is one MMC test tools called mmc-utils, which is maintained by Ulf Hansson,
you can find it at the below public git repository:
- https://git.kernel.org/cgit/linux/kernel/git/cjb/mmc-utils.git/
+ https://git.kernel.org/pub/scm/utils/mmc/mmc-utils.git
Functions
=========
diff --git a/Documentation/driver-api/thermal/sysfs-api.rst b/Documentation/driver-api/thermal/sysfs-api.rst
index c93fa5e961a0..2e0f79a9e2ee 100644
--- a/Documentation/driver-api/thermal/sysfs-api.rst
+++ b/Documentation/driver-api/thermal/sysfs-api.rst
@@ -428,6 +428,9 @@ of thermal zone device. E.g. the generic thermal driver registers one hwmon
class device and build the associated hwmon sysfs I/F for all the registered
ACPI thermal zones.
+Please read Documentation/ABI/testing/sysfs-class-thermal for thermal
+zone and cooling device attribute details.
+
::
/sys/class/hwmon/hwmon[0-*]:
@@ -437,228 +440,6 @@ ACPI thermal zones.
Please read Documentation/hwmon/sysfs-interface.rst for additional information.
-Thermal zone attributes
------------------------
-
-type
- Strings which represent the thermal zone type.
- This is given by thermal zone driver as part of registration.
- E.g: "acpitz" indicates it's an ACPI thermal device.
- In order to keep it consistent with hwmon sys attribute; this should
- be a short, lowercase string, not containing spaces nor dashes.
- RO, Required
-
-temp
- Current temperature as reported by thermal zone (sensor).
- Unit: millidegree Celsius
- RO, Required
-
-mode
- One of the predefined values in [enabled, disabled].
- This file gives information about the algorithm that is currently
- managing the thermal zone. It can be either default kernel based
- algorithm or user space application.
-
- enabled
- enable Kernel Thermal management.
- disabled
- Preventing kernel thermal zone driver actions upon
- trip points so that user application can take full
- charge of the thermal management.
-
- RW, Optional
-
-policy
- One of the various thermal governors used for a particular zone.
-
- RW, Required
-
-available_policies
- Available thermal governors which can be used for a particular zone.
-
- RO, Required
-
-`trip_point_[0-*]_temp`
- The temperature above which trip point will be fired.
-
- Unit: millidegree Celsius
-
- RO, Optional
-
-`trip_point_[0-*]_type`
- Strings which indicate the type of the trip point.
-
- E.g. it can be one of critical, hot, passive, `active[0-*]` for ACPI
- thermal zone.
-
- RO, Optional
-
-`trip_point_[0-*]_hyst`
- The hysteresis value for a trip point, represented as an integer
- Unit: Celsius
- RW, Optional
-
-`cdev[0-*]`
- Sysfs link to the thermal cooling device node where the sys I/F
- for cooling device throttling control represents.
-
- RO, Optional
-
-`cdev[0-*]_trip_point`
- The trip point in this thermal zone which `cdev[0-*]` is associated
- with; -1 means the cooling device is not associated with any trip
- point.
-
- RO, Optional
-
-`cdev[0-*]_weight`
- The influence of `cdev[0-*]` in this thermal zone. This value
- is relative to the rest of cooling devices in the thermal
- zone. For example, if a cooling device has a weight double
- than that of other, it's twice as effective in cooling the
- thermal zone.
-
- RW, Optional
-
-emul_temp
- Interface to set the emulated temperature method in thermal zone
- (sensor). After setting this temperature, the thermal zone may pass
- this temperature to platform emulation function if registered or
- cache it locally. This is useful in debugging different temperature
- threshold and its associated cooling action. This is write only node
- and writing 0 on this node should disable emulation.
- Unit: millidegree Celsius
-
- WO, Optional
-
- WARNING:
- Be careful while enabling this option on production systems,
- because userland can easily disable the thermal policy by simply
- flooding this sysfs node with low temperature values.
-
-sustainable_power
- An estimate of the sustained power that can be dissipated by
- the thermal zone. Used by the power allocator governor. For
- more information see Documentation/driver-api/thermal/power_allocator.rst
-
- Unit: milliwatts
-
- RW, Optional
-
-k_po
- The proportional term of the power allocator governor's PID
- controller during temperature overshoot. Temperature overshoot
- is when the current temperature is above the "desired
- temperature" trip point. For more information see
- Documentation/driver-api/thermal/power_allocator.rst
-
- RW, Optional
-
-k_pu
- The proportional term of the power allocator governor's PID
- controller during temperature undershoot. Temperature undershoot
- is when the current temperature is below the "desired
- temperature" trip point. For more information see
- Documentation/driver-api/thermal/power_allocator.rst
-
- RW, Optional
-
-k_i
- The integral term of the power allocator governor's PID
- controller. This term allows the PID controller to compensate
- for long term drift. For more information see
- Documentation/driver-api/thermal/power_allocator.rst
-
- RW, Optional
-
-k_d
- The derivative term of the power allocator governor's PID
- controller. For more information see
- Documentation/driver-api/thermal/power_allocator.rst
-
- RW, Optional
-
-integral_cutoff
- Temperature offset from the desired temperature trip point
- above which the integral term of the power allocator
- governor's PID controller starts accumulating errors. For
- example, if integral_cutoff is 0, then the integral term only
- accumulates error when temperature is above the desired
- temperature trip point. For more information see
- Documentation/driver-api/thermal/power_allocator.rst
-
- Unit: millidegree Celsius
-
- RW, Optional
-
-slope
- The slope constant used in a linear extrapolation model
- to determine a hotspot temperature based off the sensor's
- raw readings. It is up to the device driver to determine
- the usage of these values.
-
- RW, Optional
-
-offset
- The offset constant used in a linear extrapolation model
- to determine a hotspot temperature based off the sensor's
- raw readings. It is up to the device driver to determine
- the usage of these values.
-
- RW, Optional
-
-Cooling device attributes
--------------------------
-
-type
- String which represents the type of device, e.g:
-
- - for generic ACPI: should be "Fan", "Processor" or "LCD"
- - for memory controller device on intel_menlow platform:
- should be "Memory controller".
-
- RO, Required
-
-max_state
- The maximum permissible cooling state of this cooling device.
-
- RO, Required
-
-cur_state
- The current cooling state of this cooling device.
- The value can any integer numbers between 0 and max_state:
-
- - cur_state == 0 means no cooling
- - cur_state == max_state means the maximum cooling.
-
- RW, Required
-
-stats/reset
- Writing any value resets the cooling device's statistics.
- WO, Required
-
-stats/time_in_state_ms:
- The amount of time spent by the cooling device in various cooling
- states. The output will have "<state> <time>" pair in each line, which
- will mean this cooling device spent <time> msec of time at <state>.
- Output will have one line for each of the supported states.
- RO, Required
-
-
-stats/total_trans:
- A single positive value showing the total number of times the state of a
- cooling device is changed.
-
- RO, Required
-
-stats/trans_table:
- This gives fine grained information about all the cooling state
- transitions. The cat output here is a two dimensional matrix, where an
- entry <i,j> (row i, column j) represents the number of transitions from
- State_i to State_j. If the transition table is bigger than PAGE_SIZE,
- reading this will return an -EFBIG error.
- RO, Required
-
3. A simple implementation
==========================