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diff --git a/Documentation/driver-api/drivers.rst b/Documentation/driver-api/drivers.rst deleted file mode 100644 index 17f99d441b52..000000000000 --- a/Documentation/driver-api/drivers.rst +++ /dev/null @@ -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: |