Tài liệu Linux Device Drivers-Chapter 5 : Enhanced Char Driver Operations pptx

... stop. Chapter 5 : Enhanced Char Driver Operations In Chapter 3, " ;Char Drivers", we built a complete device driver that the user can write to and read from. But a real device usually ... the same device) is best solved by implementing one device node for each access policy. An example of this practice can be found in the Linux tape driver, which prov...

Ngày tải lên: 24/12/2013, 01:17

... 3: Char Drivers The goal of this chapter is to write a complete char device driver. We'll develop a character driver because this class is suitable for most simple hardware devices. Char ... Control on a Device File" in Chapter 5, " ;Enhanced Char Driver Operations& quot;, the code for sculluid will demonstrate how the driver can enforce its own kind...

Ngày tải lên: 24/12/2013, 01:17

... functions, as shown in "Going to Sleep and Awakening" in Chapter 5, " ;Enhanced Char Driver Operations& quot ;: Causes an "infinitely rescheduling'' tasklet to cease execution. ... #include < ;linux/ delay.h> void udelay(unsigned long usecs); Chapter 6 : Flow of Time At this point, we know the basics of how to write a full-featured char...

Ngày tải lên: 24/12/2013, 01:17

... sign: morgana.root# cat /proc/1/maps # look at init 08048000-0804e000 r-xp 00000000 0 8:0 1 51 297 /sbin/init # text 0804e000-08 050 000 rw-p 000 050 00 0 8:0 1 51 297 /sbin/init # data 08 050 000-08 054 000 ... used by the driver to store its own information. Like struct vm_area_struct, the vm _operations_ struct is defined in < ;linux/ mm.h>; it includes the operations...

Ngày tải lên: 21/01/2014, 07:20

... Chapter 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 ... advanced features of char drivers, such as blocking operations, the use of select, and the important ioctl call; these topics are the subject of Chapter 5, " ;Enhanced Cha...

Ngày tải lên: 24/12/2013, 01:17

... Control on a Device File", in Chapter 5, " ;Enhanced Char Driver Operations& quot;. Actually, current is not properly a global variable any more, like it was in the first Linux kernels. ... the device; a smart driver process can thus allow concurrent access to the device. This is exactly how the X server works. Another example of a user-space driver is the gpm...

Ngày tải lên: 24/12/2013, 01:17

... 001 0:[ faulty:faulty_write+3 /57 6] EFLAGS: 00010286 eax: ffffffea ebx: c2c55ae0 ecx: c48370c0 edx: c2c55b00 esi: 0804d038 edi: 0804d038 ebp: c2337f8c esp: c2337f8c ds: 0018 es: 0018 ss: 0018 Process cat (pid: 23413, stackpage=c2337000) ... eip: c48370c3 *pde = 00000000 Oops: 0002 CPU: 0 EIP: 001 0:[ <c48370c3>] EFLAGS: 00010286 eax: ffffffea ebx: c2281a20 ecx: c48370...

Ngày tải lên: 24/12/2013, 01:17

... 0:c262b000 1:c2193000 rudo% cat /tmp/bigfile > /dev/scullv0; head -5 /proc/scullvmem Device 0: qset 50 0, order 4, sz 104 857 6 item at c4184b80, qset at c71c4000 0:c881a000 1:c882b000 ... 1:e000000024778000 salma% cat /tmp/bigfile > /dev/scullv0; head -5 /proc/scullvmem Device 0: qset 50 0, order 4, sz 104 857 6 item at e0000000303699c0, qset at e00...

Ngày tải lên: 24/12/2013, 01:17

... port); Chapter 8 :Hardware Management Although playing with scull and similar toys is a good introduction to the software interface of a Linux device driver, implementing a real device requires ... following: if (check_mem_region(mem_addr, mem_size)) { printk("drivername: memory already in use\n"); return -EBUSY; } request_mem_region(mem_addr, mem_size, "dri...

Ngày tải lên: 24/12/2013, 01:17

... 1 0: 56 5910 56 5269 IO-APIC-level aic7xxx 1 2: 889091 884276 IO-APIC-edge PS/2 Mouse 1 3: 1 0 XT-PIC fpu 1 5: 1 759 669 173 452 0 IO-APIC-edge ide1 NMI: 6 952 0392 6 952 0392 LOC: 6 951 3717 6 951 3716 ... short by specifying bh= 1: morgana% echo 1122334 455 > /dev/shortint ; cat /dev/shortint bh after 5 50 588804.876 653 50 588804.876693 50 588804.876720...

Ngày tải lên: 24/12/2013, 01:17