On 7/27/06, Ulises <uarcidiacono@xxxxxxxxx> wrote:
Hi All,
I'm making a bar code reader driver. This device will be conected by the
serial port.
In my init_module() I have:
if ((request_region (0x3F8, 1, "BARCODEREADER_NAME") == NULL))
{
.. Error handling ...
}
The problem is that always I get a NULL pointer. I think the problem is
because this address is already taken by another device. Please take a
look to my cat /proc/ioports:
0000-001f : dma1
0020-0021 : pic1
0040-0043 : timer0
0050-0053 : timer1
0060-006f : keyboard
0070-0077 : rtc
0080-008f : dma page reg
00a0-00a1 : pic2
00c0-00df : dma2
00f0-00ff : fpu
0170-0177 : ide1
01f0-01f7 : ide0
0300-0301 : MPU401 UART
0376-0376 : ide1
0378-037a : parport0
03c0-03df : vga+
03f6-03f6 : ide0
*03f8-03ff : serial*
0cf8-0cff : PCI conf1
5080-5093 : sis630_smbus
a000-afff : PCI Bus #01
cc00-ccff : 0000:00:01.1
cc00-ccff : sis900
d000-d0ff : 0000:00:01.4
d000-d0ff : Trident Audio
d400-d47f : 0000:00:01.6
d800-d8ff : 0000:00:01.6
ff00-ff0f : 0000:00:00.1
ff00-ff07 : ide0
ff08-ff0f : ide1
So, My question is:
If I can remove this "serial" driver, Will I have this address free to
use it by "my device"?
Yes. Even if you don't free, you still can use the ioports within the
kernel. When you use request_region() you are just making sure that
only you will use it. Its something like a semaphore. You still can
enter the critical section(ie, use the ports), if you don't wish to
follow the rules.
In case I can remove the "serial" module, Where can I fin it?
I cannot find a module called "serial" doing lsmod. These are all that I
Your system need not have a module named serial. The name 'serial' is
what you have given when you had requested the port. The actual driver
could be different(like 8250). Also, if the driver is compiled into
the kernel, you may have to reconfigure it.
have:
$ lsmod | grep seri*
cpufreq_userspace 4824 0
cpufreq_conservative 7588 0
serio_raw 7556 0
Thank You,
Jinesh.
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