linux device drivers by rubini pdf free download
Tài liệu Linux Device Drivers-Chapter 15 :Overview of Peripheral Buses pdf
Ngày tải lên :
21/01/2014, 07:20
... the usual case of a static device list is
handled by scanning the device list once for each device at system boot;
modularized drivers will just unload as usual if no device is there, and an
external ... for newer drivers.
The basic idea being exploited is that whenever a new device appears during
the system's lifetime, all available device drivers must check whether the
new device is ... That's how compiled-in device drivers perform their
initialization; it is not used directly by modularized code. The return
value is a count of devices being handled by the driver.
int pci_module_init(struct...
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Tài liệu Linux Device Drivers-Chapter 1 :An Introduction to Device Drivers ppt
Ngày tải lên :
24/12/2013, 01:17
... 1 :An Introduction to Device Drivers
As the popularity of the Linux system continues to grow, the interest in
writing Linux device drivers steadily increases. Most of Linux is
independent ... supported by
Linux, somebody somewhere has written a driver to make it work with the
system. Without device drivers, there is no functioning system.
Device drivers take on a special role in the Linux ... independent of the devices attached to
the SCSI cable.
Other classes of device drivers have been added to the kernel in recent times,
including USB drivers, FireWire drivers, and I2O drivers. In...
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Tài liệu Linux Device Drivers-Chapter 2 : Building and Running Modules pptx
Ngày tải lên :
24/12/2013, 01:17
... new device, it will be able to avoid probing those ports that are
already in use by other drivers.
ISA probing is in fact a risky task, and several drivers distributed with the
official Linux ... of a device driver, it might offer a plug for
hardware-specific implementations. For example, the video-for -linux set of
drivers is split into a generic module that exports symbols used by lower-
level ... not belong to any of the classes listed in
"Classes of Devices and Modules" in Chapter 1, "An Introduction to Device
Drivers& quot;. The sample driver shown in this chapter is called...
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Tài liệu Linux Device Drivers-Chapter 3: Char Drivers docx
Ngày tải lên :
24/12/2013, 01:17
...
The region of memory used by scull, also called a device here, is variable in
length. The more you write, the more it grows; trimming is performed by
overwriting the device with a shorter file. ... the scull device.
In scull, each device is a linked list of pointers, each of which points to a
Scull_Dev structure. Each such structure can refer, by default, to at most
four million bytes, ... the minor number of
the device, so the driver is free to use it at will. In practice, different minor
numbers are used to access different devices or to open the same device in a
different way....
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Tài liệu Linux Device Drivers-Chapter 4 : Debugging Techniques pptx
Ngày tải lên :
24/12/2013, 01:17
... special ioctl command TIOCLINUX, which implements
Linux- specific functions. To use TIOCLINUX, you pass it an argument that
is a pointer to a byte array. The first byte of the array is a number ...
/proc is heavily used in the Linux system. Many utilities on a modern Linux
distribution, such as ps, top, and uptime, get their information from /proc.
Some device drivers also export information ... following bytes are
subcommand specific. In setconsole, subcommand 11 is used, and the next
byte (stored in bytes[1]) identifies the virtual console. The complete
description of TIOCLINUX can...
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Tài liệu Linux Device Drivers-Chapter 5 : Enhanced Char Driver Operations pptx
Ngày tải lên :
24/12/2013, 01:17
... arguments by pointer
and by explicit value, although by an established convention ioctl should
for reading. When some data has been written to the hardware device,
and space becomes free in ... free to do it differently.
Though the ioctl system call is most often used to act on devices, a few
commands are recognized by the kernel. Note that these commands, when
applied to your device, ... implementing device control this way is that the user can control
the device just by writing data, without needing to use (or sometimes write)
programs built just for configuring the device.
For...
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Tài liệu Linux Device Drivers-Chapter 6 : Flow of Time pptx
Ngày tải lên :
24/12/2013, 01:17
... < ;linux/ delay.h>
void udelay(unsigned long usecs);
protected from concurrent access, either by being atomic types (discussed in
Chapter 10, "Judicious Use of Data Types") or by ... generated by the system's timing hardware at regular
intervals; this interval is set by the kernel according to the value of HZ,
which is an architecture-dependent value defined in < ;linux/ param.h>. ... "Interrupt
Handling". For now, suffice it to say that a bottom half is a mechanism
provided by a device driver to handle asynchronous tasks which, usually, are
too large to be done while handling...
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Tài liệu Linux Device Drivers-Chapter 7 : Getting Hold of Memory doc
Ngày tải lên :
24/12/2013, 01:17
... cache. Device drivers normally do not exhibit the sort of memory
behavior that justifies using a lookaside cache, but there can be exceptions;
the USB and ISDN drivers in Linux 2.4 use caches.
Linux ... happens, the Linux kernel
takes advantage of the feature, and both the kernel and get _free_ pages
addresses lie in one of those memory ranges. The difference is transparent to
device drivers and ... verify, by
looking in /proc/ksyms, that kernel symbols exported by modules lie in a
different memory range than symbols exported by the kernel proper.
Memory allocated with vmalloc is released by...
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Tài liệu Linux Device Drivers-Chapter 8 :Hardware Management docx
Ngày tải lên :
24/12/2013, 01:17
...
address ranges bypasses the MMU, and any access to one of those ranges
bypasses the cache as well. A section of these 512 megabytes is reserved for
peripheral devices, and drivers can access ... burned in device logic circuits, statically assigned in local device
memory, or set by means of physical jumpers. The latter is true of PCI
devices, whose addresses are assigned by system software ... ports are:
#include < ;linux/ ioport.h>
can be either hardwired in the device or assigned by system firmware at boot
time. The former is true, for example, of ISA devices, whose addresses...
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Tài liệu Linux Device Drivers-Chapter 9 :Interrupt Handling Although doc
Ngày tải lên :
24/12/2013, 01:17
... wouldn't contribute to
system entropy anyway. Devices that could be influenced by attackers
should not set this flag; for example, network drivers can be subjected
to predictable packet timing ... long as you don't use the two devices at the same time. It is quite
common for users to load the module for a special device at system boot,
even if the device is rarely used. A data acquisition ... :Interrupt Handling
Although some devices can be controlled using nothing but their I/O
regions, most real-world devices are a bit more complicated than that.
Devices have to deal with the external...
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Tài liệu Linux Device Drivers-Chapter 10 :Judicious Use of Data Types doc
Ngày tải lên :
24/12/2013, 01:17
...
Not all Linux versions defined all the macros that deal with byte ordering. In
particular, the linux/ byteorderdirectory appeared in version 2.1.72 to make
order in the various <asm/byteorder.h> ... power of two, independent of PAGE_SIZE.
Byte Order
Be careful not to make assumptions about byte ordering. Whereas the PC
stores multibyte values low-byte first (little end first, thus little-endian), ...
Functions for converting between known byte orders and that of the
processor. There are more than 60 such functions; see the various files
in include /linux/ byteorder/ for a full list and the ways...
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Tài liệu Linux Device Drivers-Chapter 11 : kmod and Advanced docx
Ngày tải lên :
21/01/2014, 07:20
... is thus handled by mangling the name of
each symbol exported by the kernel to include the checksum of all the
information related to that symbol. This information is obtained by parsing
the ... the versioned names for all the symbols exported by the
kernel.
__GENKSYMS__
This macro is defined by make when preprocessing files to be read by
genksymsto build new version codes. It is used ... call_usermodehelper; it is used primarily by
the hot-plug subsystem (i.e., for USB devices and such) to perform module
loading and configuration tasks when a new device is attached to the system.
Its...
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Tài liệu Linux Device Drivers-Chapter 12 : Loading Block Drivers docx
Ngày tải lên :
21/01/2014, 07:20
... handlers is convenient when the device can issue interrupts with
different meanings.
DEVICE_ ON(kdev_t device)
DEVICE_ OFF(kdev_t device)
These macros are intended to help devices that need to perform ... follows:
size=2048 (kilobytes)
Each RAM disk created by sbull takes two megabytes of RAM.
blksize=1024 (bytes)
The software "block'' used by the module is one kilobyte, like the
system ... performed on the size of the device (i.e., the
kernel might request data transfers past end-of -device) .
int blksize_size[][];
The size of the block used by each device, in bytes. Like the previous...
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Tài liệu Linux Device Drivers-Chapter 13 :mmap and DMA pptx
Ngày tải lên :
21/01/2014, 07:20
... count of the
first page in a cluster is incremented by get _free_ pages and decremented by
free_ pages. The mmap method is disabled for a scullp device if the
allocation order is greater than zero, ... and similar devices, which are truncated to a length of zero
when opened for writing. Refusing to free a mapped scullp device allows a
process to overwrite regions actively mapped by another ... controls how get _free_ pagesis invoked (see Chapter 7,
"Getting Hold of Memory", "get _free_ page and Friends"). This choice is
dictated by the internals of get _free_ pages, the...
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