enabling LKM for custom beeper

PATCH New Christian W. Zuckschwerdt 1 participant 1 message Jan 28, 2001

Subsystems (2)

TTY layer and serial drivers Char and misc drivers

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Christian W. Zuckschwerdt

author

2001-01-28 21:51 UTC #0 lore raw

PATCH 1/1 enabling LKM for custom beeper

Hi Linus, Alan,

this patch has proven to be stable an useable. It hasn't changed since 2.2.13.

The patch affects kd_mksound and kd_nosound which are responsible for generating sound.
The default behaviour won't be changed but it's now possible for a LKM to hook into these calls and change the way the system bell rings.

Changes in struct timer_list made a separate patch for 2.4.0 necessary.

Please incorporante into next release of 2.{2,4} if appropriate; TIA,

cu.

    :
    Christian

char/vt.c renamed from char/vt.c.orig +5 -3

@@ -92,18 +92,20 @@
     || (defined(__mips__) && !defined(CONFIG_SGI))
 
 static void
-kd_nosound(unsigned long ignored)
+_kd_nosound(unsigned long ignored)
 {
 	/* disable counter 2 */
 	outb(inb_p(0x61)&0xFC, 0x61);
 	return;
 }
 
-void
+void (*kd_nosound)(unsigned long ignored) = _kd_nosound;
+
+static void
 _kd_mksound(unsigned int hz, unsigned int ticks)
 {
 	static struct timer_list sound_timer = { NULL, NULL, 0, 0,
-						 kd_nosound };
+						 _kd_nosound };
 
 	unsigned int count = 0;

ksyms.c renamed from ksyms.c.orig +5 -0

@@ -62,6 +62,9 @@
 extern void free_dma(unsigned int dmanr);
 extern spinlock_t dma_spin_lock;
 
+extern void (*kd_nosound)(unsigned long ignored);
+extern void (*kd_mksound)(unsigned int count, unsigned int ticks);
+
 #ifdef CONFIG_MODVERSIONS
 const struct module_symbol __export_Using_Versions
 __attribute__((section("__ksymtab"))) = {

@@ -341,6 +344,8 @@
 EXPORT_SYMBOL(register_reboot_notifier);
 EXPORT_SYMBOL(unregister_reboot_notifier);
 EXPORT_SYMBOL(_ctype);
+EXPORT_SYMBOL(kd_nosound);
+EXPORT_SYMBOL(kd_mksound);
 EXPORT_SYMBOL(secure_tcp_sequence_number);
 EXPORT_SYMBOL(get_random_bytes);
 EXPORT_SYMBOL(securebits);

linux/vt_kern.h renamed from linux/vt_kern.h.orig +1 -1

@@ -30,7 +30,7 @@
 	struct wait_queue *paste_wait;
 } *vt_cons[MAX_NR_CONSOLES];
 
-void (*kd_mksound)(unsigned int hz, unsigned int ticks);
+extern void (*kd_mksound)(unsigned int hz, unsigned int ticks);
 
 /* console.c */

drivers/char/vt.c +5 -3

@@ -98,17 +98,19 @@
     || (defined(__arm__) && defined(CONFIG_HOST_FOOTBRIDGE))
 
 static void
-kd_nosound(unsigned long ignored)
+_kd_nosound(unsigned long ignored)
 {
 	/* disable counter 2 */
 	outb(inb_p(0x61)&0xFC, 0x61);
 	return;
 }
 
-void
+void (*kd_nosound)(unsigned long ignored) = _kd_nosound;
+
+static void
 _kd_mksound(unsigned int hz, unsigned int ticks)
 {
-	static struct timer_list sound_timer = { function: kd_nosound };
+	static struct timer_list sound_timer = { function: _kd_nosound };
 	unsigned int count = 0;
 	unsigned long flags;

include/linux/vt_kern.h +1 -1

@@ -30,7 +30,7 @@
 	wait_queue_head_t paste_wait;
 } *vt_cons[MAX_NR_CONSOLES];
 
-void (*kd_mksound)(unsigned int hz, unsigned int ticks);
+extern void (*kd_mksound)(unsigned int hz, unsigned int ticks);
 
 /* console.c */

kernel/ksyms.c +5 -0

@@ -62,6 +62,9 @@
 extern void free_dma(unsigned int dmanr);
 extern spinlock_t dma_spin_lock;
 
+extern void (*kd_nosound)(unsigned long ignored);
+extern void (*kd_mksound)(unsigned int count, unsigned int ticks);
+
 #ifdef CONFIG_MODVERSIONS
 const struct module_symbol __export_Using_Versions
 __attribute__((section("__ksymtab"))) = {

@@ -455,6 +458,8 @@
 EXPORT_SYMBOL(machine_halt);
 EXPORT_SYMBOL(machine_power_off);
 EXPORT_SYMBOL(_ctype);
+EXPORT_SYMBOL(kd_nosound);
+EXPORT_SYMBOL(kd_mksound);
 EXPORT_SYMBOL(secure_tcp_sequence_number);
 EXPORT_SYMBOL(get_random_bytes);
 EXPORT_SYMBOL(securebits);