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<H2><A NAME="s8">8. Patches to make PLIP and LP live together.</A></H2>
<P>The best way to make PLIP and LP live together is to use kernel modules: you
can load plip.o and unload it when you need to print or vice versa.
If you do really need to use both PLIP and LP, try the following patches.
<P>
<H2><A NAME="ss8.1">8.1 PLIP and LP together on the same port.</A>
</H2>
<P>If for some reason you wish PLIP and LP supported directly by the kernel,
you can try these patches.
<P>You must modify the following pieces of code, but <EM>backup</EM> the files
before:
<P>
<HR>
<PRE>
******** modifications to linux/drivers/char/lp.c ***********************
struct lp_struct lp_table[] = {
{ 0x3bc, 0, 0, LP_INIT_CHAR, LP_INIT_TIME, LP_INIT_WAIT, NULL,
NULL, },
/* { 0x378, 0, 0, LP_INIT_CHAR, LP_INIT_TIME, LP_INIT_WAIT, NULL,
NULL, },
{ 0x278, 0, 0, LP_INIT_CHAR, LP_INIT_TIME, LP_INIT_WAIT, NULL,
NULL, },
*/
};
#define LP_NO 1
******** modifications to linux/drivers/net/Space.c ********************
#if defined(PLIP) || defined(CONFIG_PLIP)
extern int plip_init(struct device *);
static struct device plip2_dev = {
"plip2", 0, 0, 0, 0, 0x278, 2, 0, 0, 0, NEXT_DEV, plip_init, };
static struct device plip1_dev = {
"plip1", 0, 0, 0, 0, 0x378, 7, 0, 0, 0, &plip2_dev, plip_init, };
/* static struct device plip0_dev = {
"plip0", 0, 0, 0, 0, 0x3BC, 5, 0, 0, 0, &plip1_dev, plip_init, };
*/
# undef NEXT_DEV
# define NEXT_DEV (&plip1_dev)
#endif /* PLIP */
</PRE>
<HR>
<P>Of course there is the standard disclaimer: <EM>I received these patches and
I put them "as I got them". This means that you try them at your own risk.</EM>
Anyway, your biggest trouble should be only restore the original files and
recompile.
<P>
<H2><A NAME="ss8.2">8.2 PLIP and LP on different ports.</A>
</H2>
<P>If you have at least 2 parallel ports you can try these patches, that
should allow you to use PLIP on a port and LP on the other.
<P>
<OL>
<LI>Comment out one line in kernel source file, drivers/char/lp.c.
<HR>
<PRE>
struct lp_struct lp_table[] = {
{ 0x3bc, 0, 0, LP_INIT_CHAR, LP_INIT_TIME, LP_INIT_WAIT, NULL, NULL, },
{ 0x378, 0, 0, LP_INIT_CHAR, LP_INIT_TIME, LP_INIT_WAIT, NULL, NULL, },
/* { 0x278, 0, 0, LP_INIT_CHAR, LP_INIT_TIME, LP_INIT_WAIT, NULL, NULL, }, */
};
3 -> 2
</PRE>
<HR>
</LI>
<LI>Kernel configuration
<BLOCKQUOTE><CODE>
<PRE>
PLIP (parallel port) support (CONFIG_PLIP) [n] y
Parallel Printer support [y] y
</PRE>
</CODE></BLOCKQUOTE>
</LI>
<LI>Kernel message at startup
<BLOCKQUOTE><CODE>
<PRE>
lp1 at 0x0378, using polling driver
.....
NET3 PLIP version 2.0 gniibe@mri.co.jp
plip2: Parallel port at 0x278, using assigned IRQ 5.
</PRE>
</CODE></BLOCKQUOTE>
</LI>
</OL>
<P>Again the standard disclaimer, like section 8.1.
<P>
<P>
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