We don't need to keep it as a single large file anymore; split it up so that it is easier to manage and the individual sections can be read directly as plain files. Signed-off-by: Jonathan Corbet <corbet@lwn.net>tirimbino
parent
47cb398dd7
commit
dcec3c8c9a
@ -0,0 +1,120 @@ |
||||
Driver Basics |
||||
============= |
||||
|
||||
Driver Entry and Exit points |
||||
---------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/init.h |
||||
:internal: |
||||
|
||||
Atomic and pointer manipulation |
||||
------------------------------- |
||||
|
||||
.. kernel-doc:: arch/x86/include/asm/atomic.h |
||||
:internal: |
||||
|
||||
Delaying, scheduling, and timer routines |
||||
---------------------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/sched.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/sched/core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/sched/cpupri.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/sched/fair.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: include/linux/completion.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/time/timer.c |
||||
:export: |
||||
|
||||
Wait queues and Wake events |
||||
--------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/wait.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/sched/wait.c |
||||
:export: |
||||
|
||||
High-resolution timers |
||||
---------------------- |
||||
|
||||
.. kernel-doc:: include/linux/ktime.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: include/linux/hrtimer.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/time/hrtimer.c |
||||
:export: |
||||
|
||||
Workqueues and Kevents |
||||
---------------------- |
||||
|
||||
.. kernel-doc:: include/linux/workqueue.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/workqueue.c |
||||
:export: |
||||
|
||||
Internal Functions |
||||
------------------ |
||||
|
||||
.. kernel-doc:: kernel/exit.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/signal.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: include/linux/kthread.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/kthread.c |
||||
:export: |
||||
|
||||
Kernel objects manipulation |
||||
--------------------------- |
||||
|
||||
.. kernel-doc:: lib/kobject.c |
||||
:export: |
||||
|
||||
Kernel utility functions |
||||
------------------------ |
||||
|
||||
.. kernel-doc:: include/linux/kernel.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/printk/printk.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/panic.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/sys.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/srcu.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/tree.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/tree_plugin.h |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/update.c |
||||
:export: |
||||
|
||||
Device Resource Management |
||||
-------------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/devres.c |
||||
:export: |
||||
|
@ -1,654 +0,0 @@ |
||||
==================== |
||||
Linux Device Drivers |
||||
==================== |
||||
|
||||
Driver Basics |
||||
============= |
||||
|
||||
Driver Entry and Exit points |
||||
---------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/init.h |
||||
:internal: |
||||
|
||||
Atomic and pointer manipulation |
||||
------------------------------- |
||||
|
||||
.. kernel-doc:: arch/x86/include/asm/atomic.h |
||||
:internal: |
||||
|
||||
Delaying, scheduling, and timer routines |
||||
---------------------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/sched.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/sched/core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/sched/cpupri.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/sched/fair.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: include/linux/completion.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/time/timer.c |
||||
:export: |
||||
|
||||
Wait queues and Wake events |
||||
--------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/wait.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/sched/wait.c |
||||
:export: |
||||
|
||||
High-resolution timers |
||||
---------------------- |
||||
|
||||
.. kernel-doc:: include/linux/ktime.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: include/linux/hrtimer.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/time/hrtimer.c |
||||
:export: |
||||
|
||||
Workqueues and Kevents |
||||
---------------------- |
||||
|
||||
.. kernel-doc:: include/linux/workqueue.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/workqueue.c |
||||
:export: |
||||
|
||||
Internal Functions |
||||
------------------ |
||||
|
||||
.. kernel-doc:: kernel/exit.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/signal.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: include/linux/kthread.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/kthread.c |
||||
:export: |
||||
|
||||
Kernel objects manipulation |
||||
--------------------------- |
||||
|
||||
.. kernel-doc:: lib/kobject.c |
||||
:export: |
||||
|
||||
Kernel utility functions |
||||
------------------------ |
||||
|
||||
.. kernel-doc:: include/linux/kernel.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: kernel/printk/printk.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/panic.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/sys.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/srcu.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/tree.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/tree_plugin.h |
||||
:export: |
||||
|
||||
.. kernel-doc:: kernel/rcu/update.c |
||||
:export: |
||||
|
||||
Device Resource Management |
||||
-------------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/devres.c |
||||
:export: |
||||
|
||||
Device drivers infrastructure |
||||
============================= |
||||
|
||||
The Basic Device Driver-Model Structures |
||||
---------------------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/device.h |
||||
:internal: |
||||
|
||||
Device Drivers Base |
||||
------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/init.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/base/driver.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/syscore.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/class.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/node.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/base/firmware_class.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/transport_class.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/dd.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/platform_device.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/base/platform.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/bus.c |
||||
:export: |
||||
|
||||
Buffer Sharing and Synchronization |
||||
---------------------------------- |
||||
|
||||
The dma-buf subsystem provides the framework for sharing buffers for |
||||
hardware (DMA) access across multiple device drivers and subsystems, and |
||||
for synchronizing asynchronous hardware access. |
||||
|
||||
This is used, for example, by drm "prime" multi-GPU support, but is of |
||||
course not limited to GPU use cases. |
||||
|
||||
The three main components of this are: (1) dma-buf, representing a |
||||
sg_table and exposed to userspace as a file descriptor to allow passing |
||||
between devices, (2) fence, which provides a mechanism to signal when |
||||
one device as finished access, and (3) reservation, which manages the |
||||
shared or exclusive fence(s) associated with the buffer. |
||||
|
||||
dma-buf |
||||
~~~~~~~ |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/dma-buf.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/dma-buf.h |
||||
:internal: |
||||
|
||||
reservation |
||||
~~~~~~~~~~~ |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/reservation.c |
||||
:doc: Reservation Object Overview |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/reservation.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/reservation.h |
||||
:internal: |
||||
|
||||
fence |
||||
~~~~~ |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/fence.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/fence.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/seqno-fence.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/seqno-fence.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/fence-array.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/fence-array.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/reservation.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/reservation.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/sync_file.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/sync_file.h |
||||
:internal: |
||||
|
||||
Device Drivers DMA Management |
||||
----------------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/dma-coherent.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/dma-mapping.c |
||||
:export: |
||||
|
||||
Device Drivers Power Management |
||||
------------------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/power/main.c |
||||
:export: |
||||
|
||||
Device Drivers ACPI Support |
||||
--------------------------- |
||||
|
||||
.. kernel-doc:: drivers/acpi/scan.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/acpi/scan.c |
||||
:internal: |
||||
|
||||
Device drivers PnP support |
||||
-------------------------- |
||||
|
||||
.. kernel-doc:: drivers/pnp/core.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/pnp/card.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/pnp/driver.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/pnp/manager.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/pnp/support.c |
||||
:export: |
||||
|
||||
Userspace IO devices |
||||
-------------------- |
||||
|
||||
.. kernel-doc:: drivers/uio/uio.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/uio_driver.h |
||||
:internal: |
||||
|
||||
Parallel Port Devices |
||||
===================== |
||||
|
||||
.. kernel-doc:: include/linux/parport.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/parport/ieee1284.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/parport/share.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/parport/daisy.c |
||||
:internal: |
||||
|
||||
Message-based devices |
||||
===================== |
||||
|
||||
Fusion message devices |
||||
---------------------- |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptbase.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptbase.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptscsih.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptscsih.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptctl.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptspi.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptfc.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptlan.c |
||||
:internal: |
||||
|
||||
Sound Devices |
||||
============= |
||||
|
||||
.. kernel-doc:: include/sound/core.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: sound/sound_core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/sound/pcm.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: sound/core/pcm.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/device.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/info.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/rawmidi.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/sound.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/memory.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/pcm_memory.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/init.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/isadma.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/control.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/pcm_lib.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/hwdep.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/pcm_native.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/memalloc.c |
||||
:export: |
||||
|
||||
16x50 UART Driver |
||||
================= |
||||
|
||||
.. kernel-doc:: drivers/tty/serial/serial_core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/tty/serial/8250/8250_core.c |
||||
:export: |
||||
|
||||
Frame Buffer Library |
||||
==================== |
||||
|
||||
The frame buffer drivers depend heavily on four data structures. These |
||||
structures are declared in include/linux/fb.h. They are fb_info, |
||||
fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs. The last |
||||
three can be made available to and from userland. |
||||
|
||||
fb_info defines the current state of a particular video card. Inside |
||||
fb_info, there exists a fb_ops structure which is a collection of |
||||
needed functions to make fbdev and fbcon work. fb_info is only visible |
||||
to the kernel. |
||||
|
||||
fb_var_screeninfo is used to describe the features of a video card |
||||
that are user defined. With fb_var_screeninfo, things such as depth |
||||
and the resolution may be defined. |
||||
|
||||
The next structure is fb_fix_screeninfo. This defines the properties |
||||
of a card that are created when a mode is set and can't be changed |
||||
otherwise. A good example of this is the start of the frame buffer |
||||
memory. This "locks" the address of the frame buffer memory, so that it |
||||
cannot be changed or moved. |
||||
|
||||
The last structure is fb_monospecs. In the old API, there was little |
||||
importance for fb_monospecs. This allowed for forbidden things such as |
||||
setting a mode of 800x600 on a fix frequency monitor. With the new API, |
||||
fb_monospecs prevents such things, and if used correctly, can prevent a |
||||
monitor from being cooked. fb_monospecs will not be useful until |
||||
kernels 2.5.x. |
||||
|
||||
Frame Buffer Memory |
||||
------------------- |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/fbmem.c |
||||
:export: |
||||
|
||||
Frame Buffer Colormap |
||||
--------------------- |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/fbcmap.c |
||||
:export: |
||||
|
||||
Frame Buffer Video Mode Database |
||||
-------------------------------- |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/modedb.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/modedb.c |
||||
:export: |
||||
|
||||
Frame Buffer Macintosh Video Mode Database |
||||
------------------------------------------ |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/macmodes.c |
||||
:export: |
||||
|
||||
Frame Buffer Fonts |
||||
------------------ |
||||
|
||||
Refer to the file lib/fonts/fonts.c for more information. |
||||
|
||||
Input Subsystem |
||||
=============== |
||||
|
||||
Input core |
||||
---------- |
||||
|
||||
.. kernel-doc:: include/linux/input.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/input.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/input/ff-core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/input/ff-memless.c |
||||
:export: |
||||
|
||||
Multitouch Library |
||||
------------------ |
||||
|
||||
.. kernel-doc:: include/linux/input/mt.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/input-mt.c |
||||
:export: |
||||
|
||||
Polled input devices |
||||
-------------------- |
||||
|
||||
.. kernel-doc:: include/linux/input-polldev.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/input-polldev.c |
||||
:export: |
||||
|
||||
Matrix keyboards/keypads |
||||
------------------------ |
||||
|
||||
.. kernel-doc:: include/linux/input/matrix_keypad.h |
||||
:internal: |
||||
|
||||
Sparse keymap support |
||||
--------------------- |
||||
|
||||
.. kernel-doc:: include/linux/input/sparse-keymap.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/sparse-keymap.c |
||||
:export: |
||||
|
||||
Serial Peripheral Interface (SPI) |
||||
================================= |
||||
|
||||
SPI is the "Serial Peripheral Interface", widely used with embedded |
||||
systems because it is a simple and efficient interface: basically a |
||||
multiplexed shift register. Its three signal wires hold a clock (SCK, |
||||
often in the range of 1-20 MHz), a "Master Out, Slave In" (MOSI) data |
||||
line, and a "Master In, Slave Out" (MISO) data line. SPI is a full |
||||
duplex protocol; for each bit shifted out the MOSI line (one per clock) |
||||
another is shifted in on the MISO line. Those bits are assembled into |
||||
words of various sizes on the way to and from system memory. An |
||||
additional chipselect line is usually active-low (nCS); four signals are |
||||
normally used for each peripheral, plus sometimes an interrupt. |
||||
|
||||
The SPI bus facilities listed here provide a generalized interface to |
||||
declare SPI busses and devices, manage them according to the standard |
||||
Linux driver model, and perform input/output operations. At this time, |
||||
only "master" side interfaces are supported, where Linux talks to SPI |
||||
peripherals and does not implement such a peripheral itself. (Interfaces |
||||
to support implementing SPI slaves would necessarily look different.) |
||||
|
||||
The programming interface is structured around two kinds of driver, and |
||||
two kinds of device. A "Controller Driver" abstracts the controller |
||||
hardware, which may be as simple as a set of GPIO pins or as complex as |
||||
a pair of FIFOs connected to dual DMA engines on the other side of the |
||||
SPI shift register (maximizing throughput). Such drivers bridge between |
||||
whatever bus they sit on (often the platform bus) and SPI, and expose |
||||
the SPI side of their device as a :c:type:`struct spi_master |
||||
<spi_master>`. SPI devices are children of that master, |
||||
represented as a :c:type:`struct spi_device <spi_device>` and |
||||
manufactured from :c:type:`struct spi_board_info |
||||
<spi_board_info>` descriptors which are usually provided by |
||||
board-specific initialization code. A :c:type:`struct spi_driver |
||||
<spi_driver>` is called a "Protocol Driver", and is bound to a |
||||
spi_device using normal driver model calls. |
||||
|
||||
The I/O model is a set of queued messages. Protocol drivers submit one |
||||
or more :c:type:`struct spi_message <spi_message>` objects, |
||||
which are processed and completed asynchronously. (There are synchronous |
||||
wrappers, however.) Messages are built from one or more |
||||
:c:type:`struct spi_transfer <spi_transfer>` objects, each of |
||||
which wraps a full duplex SPI transfer. A variety of protocol tweaking |
||||
options are needed, because different chips adopt very different |
||||
policies for how they use the bits transferred with SPI. |
||||
|
||||
.. kernel-doc:: include/linux/spi/spi.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/spi/spi.c |
||||
:functions: spi_register_board_info |
||||
|
||||
.. kernel-doc:: drivers/spi/spi.c |
||||
:export: |
||||
|
||||
I\ :sup:`2`\ C and SMBus Subsystem |
||||
================================== |
||||
|
||||
I\ :sup:`2`\ C (or without fancy typography, "I2C") is an acronym for |
||||
the "Inter-IC" bus, a simple bus protocol which is widely used where low |
||||
data rate communications suffice. Since it's also a licensed trademark, |
||||
some vendors use another name (such as "Two-Wire Interface", TWI) for |
||||
the same bus. I2C only needs two signals (SCL for clock, SDA for data), |
||||
conserving board real estate and minimizing signal quality issues. Most |
||||
I2C devices use seven bit addresses, and bus speeds of up to 400 kHz; |
||||
there's a high speed extension (3.4 MHz) that's not yet found wide use. |
||||
I2C is a multi-master bus; open drain signaling is used to arbitrate |
||||
between masters, as well as to handshake and to synchronize clocks from |
||||
slower clients. |
||||
|
||||
The Linux I2C programming interfaces support only the master side of bus |
||||
interactions, not the slave side. The programming interface is |
||||
structured around two kinds of driver, and two kinds of device. An I2C |
||||
"Adapter Driver" abstracts the controller hardware; it binds to a |
||||
physical device (perhaps a PCI device or platform_device) and exposes a |
||||
:c:type:`struct i2c_adapter <i2c_adapter>` representing each |
||||
I2C bus segment it manages. On each I2C bus segment will be I2C devices |
||||
represented by a :c:type:`struct i2c_client <i2c_client>`. |
||||
Those devices will be bound to a :c:type:`struct i2c_driver |
||||
<i2c_driver>`, which should follow the standard Linux driver |
||||
model. (At this writing, a legacy model is more widely used.) There are |
||||
functions to perform various I2C protocol operations; at this writing |
||||
all such functions are usable only from task context. |
||||
|
||||
The System Management Bus (SMBus) is a sibling protocol. Most SMBus |
||||
systems are also I2C conformant. The electrical constraints are tighter |
||||
for SMBus, and it standardizes particular protocol messages and idioms. |
||||
Controllers that support I2C can also support most SMBus operations, but |
||||
SMBus controllers don't support all the protocol options that an I2C |
||||
controller will. There are functions to perform various SMBus protocol |
||||
operations, either using I2C primitives or by issuing SMBus commands to |
||||
i2c_adapter devices which don't support those I2C operations. |
||||
|
||||
.. kernel-doc:: include/linux/i2c.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/i2c/i2c-boardinfo.c |
||||
:functions: i2c_register_board_info |
||||
|
||||
.. kernel-doc:: drivers/i2c/i2c-core.c |
||||
:export: |
||||
|
||||
High Speed Synchronous Serial Interface (HSI) |
||||
============================================= |
||||
|
||||
High Speed Synchronous Serial Interface (HSI) is a serial interface |
||||
mainly used for connecting application engines (APE) with cellular modem |
||||
engines (CMT) in cellular handsets. HSI provides multiplexing for up to |
||||
16 logical channels, low-latency and full duplex communication. |
||||
|
||||
.. kernel-doc:: include/linux/hsi/hsi.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/hsi/hsi_core.c |
||||
:export: |
||||
|
||||
Pulse-Width Modulation (PWM) |
||||
============================ |
||||
|
||||
Pulse-width modulation is a modulation technique primarily used to |
||||
control power supplied to electrical devices. |
||||
|
||||
The PWM framework provides an abstraction for providers and consumers of |
||||
PWM signals. A controller that provides one or more PWM signals is |
||||
registered as :c:type:`struct pwm_chip <pwm_chip>`. Providers |
||||
are expected to embed this structure in a driver-specific structure. |
||||
This structure contains fields that describe a particular chip. |
||||
|
||||
A chip exposes one or more PWM signal sources, each of which exposed as |
||||
a :c:type:`struct pwm_device <pwm_device>`. Operations can be |
||||
performed on PWM devices to control the period, duty cycle, polarity and |
||||
active state of the signal. |
||||
|
||||
Note that PWM devices are exclusive resources: they can always only be |
||||
used by one consumer at a time. |
||||
|
||||
.. kernel-doc:: include/linux/pwm.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/pwm/core.c |
||||
:export: |
@ -0,0 +1,62 @@ |
||||
Frame Buffer Library |
||||
==================== |
||||
|
||||
The frame buffer drivers depend heavily on four data structures. These |
||||
structures are declared in include/linux/fb.h. They are fb_info, |
||||
fb_var_screeninfo, fb_fix_screeninfo and fb_monospecs. The last |
||||
three can be made available to and from userland. |
||||
|
||||
fb_info defines the current state of a particular video card. Inside |
||||
fb_info, there exists a fb_ops structure which is a collection of |
||||
needed functions to make fbdev and fbcon work. fb_info is only visible |
||||
to the kernel. |
||||
|
||||
fb_var_screeninfo is used to describe the features of a video card |
||||
that are user defined. With fb_var_screeninfo, things such as depth |
||||
and the resolution may be defined. |
||||
|
||||
The next structure is fb_fix_screeninfo. This defines the properties |
||||
of a card that are created when a mode is set and can't be changed |
||||
otherwise. A good example of this is the start of the frame buffer |
||||
memory. This "locks" the address of the frame buffer memory, so that it |
||||
cannot be changed or moved. |
||||
|
||||
The last structure is fb_monospecs. In the old API, there was little |
||||
importance for fb_monospecs. This allowed for forbidden things such as |
||||
setting a mode of 800x600 on a fix frequency monitor. With the new API, |
||||
fb_monospecs prevents such things, and if used correctly, can prevent a |
||||
monitor from being cooked. fb_monospecs will not be useful until |
||||
kernels 2.5.x. |
||||
|
||||
Frame Buffer Memory |
||||
------------------- |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/fbmem.c |
||||
:export: |
||||
|
||||
Frame Buffer Colormap |
||||
--------------------- |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/fbcmap.c |
||||
:export: |
||||
|
||||
Frame Buffer Video Mode Database |
||||
-------------------------------- |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/modedb.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/core/modedb.c |
||||
:export: |
||||
|
||||
Frame Buffer Macintosh Video Mode Database |
||||
------------------------------------------ |
||||
|
||||
.. kernel-doc:: drivers/video/fbdev/macmodes.c |
||||
:export: |
||||
|
||||
Frame Buffer Fonts |
||||
------------------ |
||||
|
||||
Refer to the file lib/fonts/fonts.c for more information. |
||||
|
@ -0,0 +1,24 @@ |
||||
======================================== |
||||
The Linux driver implementer's API guide |
||||
======================================== |
||||
|
||||
The kernel offers a wide variety of interfaces to support the development |
||||
of device drivers. This document is an only somewhat organized collection |
||||
of some of those interfaces — it will hopefully get better over time! The |
||||
available subsections can be seen below. |
||||
|
||||
.. class:: toc-title |
||||
|
||||
Table of contents |
||||
|
||||
.. toctree:: |
||||
:maxdepth: 2 |
||||
|
||||
basics |
||||
infrastructure |
||||
message-based |
||||
sound |
||||
frame-buffer |
||||
input |
||||
serial-interfaces |
||||
miscellaneous |
@ -0,0 +1,169 @@ |
||||
Device drivers infrastructure |
||||
============================= |
||||
|
||||
The Basic Device Driver-Model Structures |
||||
---------------------------------------- |
||||
|
||||
.. kernel-doc:: include/linux/device.h |
||||
:internal: |
||||
|
||||
Device Drivers Base |
||||
------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/init.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/base/driver.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/syscore.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/class.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/node.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/base/firmware_class.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/transport_class.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/dd.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/platform_device.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/base/platform.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/bus.c |
||||
:export: |
||||
|
||||
Buffer Sharing and Synchronization |
||||
---------------------------------- |
||||
|
||||
The dma-buf subsystem provides the framework for sharing buffers for |
||||
hardware (DMA) access across multiple device drivers and subsystems, and |
||||
for synchronizing asynchronous hardware access. |
||||
|
||||
This is used, for example, by drm "prime" multi-GPU support, but is of |
||||
course not limited to GPU use cases. |
||||
|
||||
The three main components of this are: (1) dma-buf, representing a |
||||
sg_table and exposed to userspace as a file descriptor to allow passing |
||||
between devices, (2) fence, which provides a mechanism to signal when |
||||
one device as finished access, and (3) reservation, which manages the |
||||
shared or exclusive fence(s) associated with the buffer. |
||||
|
||||
dma-buf |
||||
~~~~~~~ |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/dma-buf.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/dma-buf.h |
||||
:internal: |
||||
|
||||
reservation |
||||
~~~~~~~~~~~ |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/reservation.c |
||||
:doc: Reservation Object Overview |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/reservation.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/reservation.h |
||||
:internal: |
||||
|
||||
fence |
||||
~~~~~ |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/fence.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/fence.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/seqno-fence.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/seqno-fence.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/fence-array.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/fence-array.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/reservation.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/reservation.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/dma-buf/sync_file.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/sync_file.h |
||||
:internal: |
||||
|
||||
Device Drivers DMA Management |
||||
----------------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/dma-coherent.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/base/dma-mapping.c |
||||
:export: |
||||
|
||||
Device Drivers Power Management |
||||
------------------------------- |
||||
|
||||
.. kernel-doc:: drivers/base/power/main.c |
||||
:export: |
||||
|
||||
Device Drivers ACPI Support |
||||
--------------------------- |
||||
|
||||
.. kernel-doc:: drivers/acpi/scan.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/acpi/scan.c |
||||
:internal: |
||||
|
||||
Device drivers PnP support |
||||
-------------------------- |
||||
|
||||
.. kernel-doc:: drivers/pnp/core.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/pnp/card.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/pnp/driver.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/pnp/manager.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/pnp/support.c |
||||
:export: |
||||
|
||||
Userspace IO devices |
||||
-------------------- |
||||
|
||||
.. kernel-doc:: drivers/uio/uio.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/linux/uio_driver.h |
||||
:internal: |
||||
|
@ -0,0 +1,51 @@ |
||||
Input Subsystem |
||||
=============== |
||||
|
||||
Input core |
||||
---------- |
||||
|
||||
.. kernel-doc:: include/linux/input.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/input.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/input/ff-core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/input/ff-memless.c |
||||
:export: |
||||
|
||||
Multitouch Library |
||||
------------------ |
||||
|
||||
.. kernel-doc:: include/linux/input/mt.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/input-mt.c |
||||
:export: |
||||
|
||||
Polled input devices |
||||
-------------------- |
||||
|
||||
.. kernel-doc:: include/linux/input-polldev.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/input-polldev.c |
||||
:export: |
||||
|
||||
Matrix keyboards/keypads |
||||
------------------------ |
||||
|
||||
.. kernel-doc:: include/linux/input/matrix_keypad.h |
||||
:internal: |
||||
|
||||
Sparse keymap support |
||||
--------------------- |
||||
|
||||
.. kernel-doc:: include/linux/input/sparse-keymap.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/input/sparse-keymap.c |
||||
:export: |
||||
|
@ -0,0 +1,30 @@ |
||||
Message-based devices |
||||
===================== |
||||
|
||||
Fusion message devices |
||||
---------------------- |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptbase.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptbase.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptscsih.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptscsih.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptctl.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptspi.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptfc.c |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/message/fusion/mptlan.c |
||||
:internal: |
||||
|
@ -0,0 +1,50 @@ |
||||
Parallel Port Devices |
||||
===================== |
||||
|
||||
.. kernel-doc:: include/linux/parport.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/parport/ieee1284.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/parport/share.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/parport/daisy.c |
||||
:internal: |
||||
|
||||
16x50 UART Driver |
||||
================= |
||||
|
||||
.. kernel-doc:: drivers/tty/serial/serial_core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: drivers/tty/serial/8250/8250_core.c |
||||
:export: |
||||
|
||||
Pulse-Width Modulation (PWM) |
||||
============================ |
||||
|
||||
Pulse-width modulation is a modulation technique primarily used to |
||||
control power supplied to electrical devices. |
||||
|
||||
The PWM framework provides an abstraction for providers and consumers of |
||||
PWM signals. A controller that provides one or more PWM signals is |
||||
registered as :c:type:`struct pwm_chip <pwm_chip>`. Providers |
||||
are expected to embed this structure in a driver-specific structure. |
||||
This structure contains fields that describe a particular chip. |
||||
|
||||
A chip exposes one or more PWM signal sources, each of which exposed as |
||||
a :c:type:`struct pwm_device <pwm_device>`. Operations can be |
||||
performed on PWM devices to control the period, duty cycle, polarity and |
||||
active state of the signal. |
||||
|
||||
Note that PWM devices are exclusive resources: they can always only be |
||||
used by one consumer at a time. |
||||
|
||||
.. kernel-doc:: include/linux/pwm.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/pwm/core.c |
||||
:export: |
||||
|
@ -0,0 +1,115 @@ |
||||
Serial Peripheral Interface (SPI) |
||||
================================= |
||||
|
||||
SPI is the "Serial Peripheral Interface", widely used with embedded |
||||
systems because it is a simple and efficient interface: basically a |
||||
multiplexed shift register. Its three signal wires hold a clock (SCK, |
||||
often in the range of 1-20 MHz), a "Master Out, Slave In" (MOSI) data |
||||
line, and a "Master In, Slave Out" (MISO) data line. SPI is a full |
||||
duplex protocol; for each bit shifted out the MOSI line (one per clock) |
||||
another is shifted in on the MISO line. Those bits are assembled into |
||||
words of various sizes on the way to and from system memory. An |
||||
additional chipselect line is usually active-low (nCS); four signals are |
||||
normally used for each peripheral, plus sometimes an interrupt. |
||||
|
||||
The SPI bus facilities listed here provide a generalized interface to |
||||
declare SPI busses and devices, manage them according to the standard |
||||
Linux driver model, and perform input/output operations. At this time, |
||||
only "master" side interfaces are supported, where Linux talks to SPI |
||||
peripherals and does not implement such a peripheral itself. (Interfaces |
||||
to support implementing SPI slaves would necessarily look different.) |
||||
|
||||
The programming interface is structured around two kinds of driver, and |
||||
two kinds of device. A "Controller Driver" abstracts the controller |
||||
hardware, which may be as simple as a set of GPIO pins or as complex as |
||||
a pair of FIFOs connected to dual DMA engines on the other side of the |
||||
SPI shift register (maximizing throughput). Such drivers bridge between |
||||
whatever bus they sit on (often the platform bus) and SPI, and expose |
||||
the SPI side of their device as a :c:type:`struct spi_master |
||||
<spi_master>`. SPI devices are children of that master, |
||||
represented as a :c:type:`struct spi_device <spi_device>` and |
||||
manufactured from :c:type:`struct spi_board_info |
||||
<spi_board_info>` descriptors which are usually provided by |
||||
board-specific initialization code. A :c:type:`struct spi_driver |
||||
<spi_driver>` is called a "Protocol Driver", and is bound to a |
||||
spi_device using normal driver model calls. |
||||
|
||||
The I/O model is a set of queued messages. Protocol drivers submit one |
||||
or more :c:type:`struct spi_message <spi_message>` objects, |
||||
which are processed and completed asynchronously. (There are synchronous |
||||
wrappers, however.) Messages are built from one or more |
||||
:c:type:`struct spi_transfer <spi_transfer>` objects, each of |
||||
which wraps a full duplex SPI transfer. A variety of protocol tweaking |
||||
options are needed, because different chips adopt very different |
||||
policies for how they use the bits transferred with SPI. |
||||
|
||||
.. kernel-doc:: include/linux/spi/spi.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/spi/spi.c |
||||
:functions: spi_register_board_info |
||||
|
||||
.. kernel-doc:: drivers/spi/spi.c |
||||
:export: |
||||
|
||||
I\ :sup:`2`\ C and SMBus Subsystem |
||||
================================== |
||||
|
||||
I\ :sup:`2`\ C (or without fancy typography, "I2C") is an acronym for |
||||
the "Inter-IC" bus, a simple bus protocol which is widely used where low |
||||
data rate communications suffice. Since it's also a licensed trademark, |
||||
some vendors use another name (such as "Two-Wire Interface", TWI) for |
||||
the same bus. I2C only needs two signals (SCL for clock, SDA for data), |
||||
conserving board real estate and minimizing signal quality issues. Most |
||||
I2C devices use seven bit addresses, and bus speeds of up to 400 kHz; |
||||
there's a high speed extension (3.4 MHz) that's not yet found wide use. |
||||
I2C is a multi-master bus; open drain signaling is used to arbitrate |
||||
between masters, as well as to handshake and to synchronize clocks from |
||||
slower clients. |
||||
|
||||
The Linux I2C programming interfaces support only the master side of bus |
||||
interactions, not the slave side. The programming interface is |
||||
structured around two kinds of driver, and two kinds of device. An I2C |
||||
"Adapter Driver" abstracts the controller hardware; it binds to a |
||||
physical device (perhaps a PCI device or platform_device) and exposes a |
||||
:c:type:`struct i2c_adapter <i2c_adapter>` representing each |
||||
I2C bus segment it manages. On each I2C bus segment will be I2C devices |
||||
represented by a :c:type:`struct i2c_client <i2c_client>`. |
||||
Those devices will be bound to a :c:type:`struct i2c_driver |
||||
<i2c_driver>`, which should follow the standard Linux driver |
||||
model. (At this writing, a legacy model is more widely used.) There are |
||||
functions to perform various I2C protocol operations; at this writing |
||||
all such functions are usable only from task context. |
||||
|
||||
The System Management Bus (SMBus) is a sibling protocol. Most SMBus |
||||
systems are also I2C conformant. The electrical constraints are tighter |
||||
for SMBus, and it standardizes particular protocol messages and idioms. |
||||
Controllers that support I2C can also support most SMBus operations, but |
||||
SMBus controllers don't support all the protocol options that an I2C |
||||
controller will. There are functions to perform various SMBus protocol |
||||
operations, either using I2C primitives or by issuing SMBus commands to |
||||
i2c_adapter devices which don't support those I2C operations. |
||||
|
||||
.. kernel-doc:: include/linux/i2c.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/i2c/i2c-boardinfo.c |
||||
:functions: i2c_register_board_info |
||||
|
||||
.. kernel-doc:: drivers/i2c/i2c-core.c |
||||
:export: |
||||
|
||||
High Speed Synchronous Serial Interface (HSI) |
||||
============================================= |
||||
|
||||
High Speed Synchronous Serial Interface (HSI) is a serial interface |
||||
mainly used for connecting application engines (APE) with cellular modem |
||||
engines (CMT) in cellular handsets. HSI provides multiplexing for up to |
||||
16 logical channels, low-latency and full duplex communication. |
||||
|
||||
.. kernel-doc:: include/linux/hsi/hsi.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: drivers/hsi/hsi_core.c |
||||
:export: |
||||
|
@ -0,0 +1,54 @@ |
||||
Sound Devices |
||||
============= |
||||
|
||||
.. kernel-doc:: include/sound/core.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: sound/sound_core.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: include/sound/pcm.h |
||||
:internal: |
||||
|
||||
.. kernel-doc:: sound/core/pcm.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/device.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/info.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/rawmidi.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/sound.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/memory.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/pcm_memory.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/init.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/isadma.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/control.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/pcm_lib.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/hwdep.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/pcm_native.c |
||||
:export: |
||||
|
||||
.. kernel-doc:: sound/core/memalloc.c |
||||
:export: |
||||
|
Loading…
Reference in new issue