ECE497 Listings for Chapter 8--Yifei

Number	Page	Caption	Listing
8-1	204	Minimal Device Driver	/* Example Minimal Character Device Driver */ #include <linux/module.h> static int __init hello_init(void) { printk(KERN_INFO "Hello Example Init\n"); return 0; } static void __exit hello_exit(void) { printk(KERN_INFO "Hello Example Exit\n"); } module_init(hello_init); module_exit(hello_exit); MODULE_AUTHOR("Chris Hallinan"); MODULE_DESCRIPTION("Hello World Example"); MODULE_LICENSE("GPL");
8-2	206	Kconfig Patch for Examples	diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index 6f31c94..0805290 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig @@ -4,6 +4,13 @@ menu "Character devices" +config EXAMPLES + tristate "Enable Examples" + default m + ---help--- + Enable compilation option for Embedded Linux Primer + driver examples + config VT bool "Virtual terminal" if EMBEDDED depends on !S390
8-3	208	Makefile Patch for Examples	diff --git a/drivers/char/Makefile b/drivers/char/Makefile index f957edf..f1b373d 100644 --- a/drivers/char/Makefile +++ b/drivers/char/Makefile @@ -102,6 +102,7 @@ obj-$(CONFIG_MWAVE) += mwave/ obj-$(CONFIG_AGP) += agp/ obj-$(CONFIG_PCMCIA) += pcmcia/ obj-$(CONFIG_IPMI_HANDLER) += ipmi/ +obj-$(CONFIG_EXAMPLES) += examples/ obj-$(CONFIG_HANGCHECK_TIMER) += hangcheck-timer.o obj-$(CONFIG_TCG_TPM) += tpm/
8-4	209	Module Build Output	beagle@embed11:~/...$ time make modules CHK include/linux/version.h make[1]: `include/asm-arm/mach-types.h' is up to date. CHK include/linux/utsrelease.h SYMLINK include/asm -> include/asm-arm CALL scripts/checksyscalls.sh <stdin>:1523:2: warning: #warning syscall recvmmsg not implemented CC [M] drivers/char/examples/hello1.o Building modules, stage 2. MODPOST 701 modules CC drivers/char/examples/hello1.mod.o LD [M] drivers/char/examples/hello1.ko real 0m28.129s user 0m38.680s sys 0m7.950s
8-5	210	Loading and Unloading a Module	# /sbin/modprobe hello1 # dmesg | tail -4 [ 73.556915] generic-usb 0003:045E:00CB.0004: input: USB HID v1.11 Mouse [Microsoft Microsoft Basic Optical Mouse v2.0 ] on usb-ehci-omap.0-2.2/input0 [ 373.735351] Alignment trap in kernel: swapper (0) PC=0xc043a30c Instr=0xe8930003 Address=0xddee002a FSR 0x001 [ 420.957183] Alignment trap in kernel: swapper (0) PC=0xc043a30c Instr=0xe8930003 Address=0xdded002a FSR 0x001 [ 1913.619354] Hello Example Init # /sbin/modprobe -r hello1 # dmesg | tail -4 [ 373.735351] Alignment trap in kernel: swapper (0) PC=0xc043a30c Instr=0xe8930003 Address=0xddee002a FSR 0x001 [ 420.957183] Alignment trap in kernel: swapper (0) PC=0xc043a30c Instr=0xe8930003 Address=0xdded002a FSR 0x001 [ 1913.619354] Hello Example Init [ 2026.515991] Hello Example Exit
8-6	211	Example Driver with Parameter	/* Example Minimal Character Device Driver */ #include <linux/module.h> static int debug_enable = 0; /* Added driver parameter */ module_param(debug_enable, int, 0); /* and these 2 lines */ MODULE_PARM_DESC(debug_enable, "Enable module debug mode."); static int __init hello_init(void) { /* Now print value of new module parameter */ printk("Hello Example Init - debug mode is %s\n", debug_enable ? "enabled" : "disabled"); return 0; } static void __exit hello_exit(void) { printk("Hello Example Exit\n"); } module_init(hello_init); module_exit(hello_exit); MODULE_AUTHOR("Chris Hallinan"); MODULE_DESCRIPTION("Hello World Example"); MODULE_LICENSE("GPL");
8-6a	211	Example Driver with Parameter	# /sbin/insmod /lib/modules/2.6.29-omap1/kernel/drivers/char/examples/hello2.ko debug_enable=1 # dmesg | tail -4 [ 49.005889] eth0: no IPv6 routers present [ 651.947784] Hello Example Init [ 677.682769] Hello Example Exit [ 2997.772644] Hello Example Init - debug mode is enabled # /sbin/rmmod hello2 # /sbin/insmod /lib/modules/2.6.29-omap1/kernel/drivers/char/examples/hello2.ko # dmesg | tail -4 [ 2990.234527] Hello Example Exit [ 2997.772644] Hello Example Init - debug mode is enabled [ 3236.012847] Hello Example Exit [ 3243.475494] Hello Example Init - debug mode is disabled
8-7	213	lsmod Example Output Format	# /sbin/lsmod Module Size Used by hello2 1520 0 hello1 1160 0 ircomm_tty 35984 0 ircomm 21144 1 ircomm_tty irda 186196 2 ircomm_tty,ircomm ipv6 274380 16 nls_iso8859_1 3856 1 rtc_twl4030 5394 0
8-8	214	Typical modprobe.conf File (not on Beagle)	$ cat /etc/modprobe.conf alias eth1 orinoci_pci options eth1 orinoco_debug=9 alias eth0 e100 alias snd-card-0 snd-intel8x0 options snd-card-0 index=0 $
8-9	216	modinfo Output	# /sbin/modinfo hello1 filename: /lib/modules/2.6.29-omap1/kernel/drivers/char/examples/hello1.ko license: GPL description: Hello World Example author: Mark A. Yoder srcversion: 43AAF2090DF58262722312B depends: vermagic: 2.6.29-omap1 preempt mod_unload modversions ARMv7
8-10	217	Adding File System Ops to Hello.c	#include <linux/module.h> #include <linux/fs.h> #define HELLO_MAJOR 234 static int debug_enable = 0; module_param(debug_enable, int, 0); MODULE_PARM_DESC(debug_enable, "Enable module debug mode."); struct file_operations hello_fops; static int hello_open(struct inode *inode, struct file *file) { printk("hello_open: successful\n"); return 0; } static int hello_release(struct inode *inode, struct file *file) { printk("hello_release: successful\n"); return 0; } static ssize_t hello_read(struct file *file, char *buf, size_t count, loff_t *ptr) { printk("hello_read: returning zero bytes\n"); return 0; } static ssize_t hello_write(struct file *file, const char *buf, size_t count, loff_t * ppos) { printk("hello_read: accepting zero bytes\n"); return 0; } static int hello_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { printk("hello_ioctl: cmd=%ld, arg=%ld\n", cmd, arg); return 0; } static int __init hello_init(void) { int ret; printk("Hello Example Init - debug mode is %s\n", debug_enable ? "enabled" : "disabled"); ret = register_chrdev(HELLO_MAJOR, "hello1", &hello_fops); if (ret < 0) { printk("Error registering hello device\n"); goto hello_fail1; } printk("Hello: registered module successfully!\n"); /* Init processing here... */ return 0; hello_fail1: return ret; } static void __exit hello_exit(void) { printk("Hello Example Exit\n"); } struct file_operations hello_fops = { owner: THIS_MODULE, read: hello_read, write: hello_write, ioctl: hello_ioctl, open: hello_open, release: hello_release, }; module_init(hello_init); module_exit(hello_exit); MODULE_AUTHOR("Chris Hallinan"); MODULE_DESCRIPTION("Hello World Example"); MODULE_LICENSE("GPL");
8-11	222	Adding File System Ops to Hello.c	#include <stdio.h> #include <stdlib.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> int main(int argc, char **argv) { /* Our file descriptor */ int fd; int rc = 0; char *rd_buf[16]; printf("%s: entered\n", argv[0]); /* Open the device */ fd = open("/dev/hello1", O_RDWR); if ( fd == -1 ) { perror("open failed"); rc = fd; exit(-1); } printf("%s: open: successful\n", argv[0]); /* Issue a read */ rc = read(fd, rd_buf, 0); if ( rc == -1 ) { perror("read failed"); close(fd); exit(-1); } printf("%s: read: returning %d bytes!\n", argv[0], rc); close(fd); return 0; }