[patch] pc-speaker driver update

[Stas Sergeev]

Hi Andrew.

Here is the patch that updates the
pcspeaker driver with the following:
1. Use i8253_lock to serialize the
port 0x43 accesses, rather than a
hand-made i8253_beep_lock.
2. Added EV_SYN/SYN_CONFIG event that
allows to disable the driver completely,
either to grant the hardware access to some
other driver, or to disable the annoying
beeps.

Acked-by: Vojtech Pavlik <vojtech@xxxxxxx>
Signed-off-by: Stas Sergeev <stsp@xxxxxxxx>

diff -urN linux-2.6.12-rc6/drivers/input/misc/pcspkr.c linux-2.6.12-rc6-spinlk/drivers/input/misc/pcspkr.c
--- linux-2.6.12-rc6/drivers/input/misc/pcspkr.c	2005-06-07 11:11:49.000000000 +0400
+++ linux-2.6.12-rc6-spinlk/drivers/input/misc/pcspkr.c	2005-06-14 12:57:59.000000000 +0400
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/input.h>
 #include <asm/8253pit.h>
+#include <asm/i8253.h>
 #include <asm/io.h>
 
 MODULE_AUTHOR("Vojtech Pavlik <vojtech@xxxxxx>");
@@ -26,27 +27,13 @@
 static char pcspkr_name[] = "PC Speaker";
 static char pcspkr_phys[] = "isa0061/input0";
 static struct input_dev pcspkr_dev;
+enum { PCSPKR_NORMAL, PCSPKR_SUSPENDED };
 
-static DEFINE_SPINLOCK(i8253_beep_lock);
-
-static int pcspkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
+static void pcspkr_do_sound(unsigned int count)
 {
-	unsigned int count = 0;
 	unsigned long flags;
 
-	if (type != EV_SND)
-		return -1;
-
-	switch (code) {
-		case SND_BELL: if (value) value = 1000;
-		case SND_TONE: break;
-		default: return -1;
-	}
-
-	if (value > 20 && value < 32767)
-		count = PIT_TICK_RATE / value;
-
-	spin_lock_irqsave(&i8253_beep_lock, flags);
+	spin_lock_irqsave(&i8253_lock, flags);
 
 	if (count) {
 		/* enable counter 2 */
@@ -61,14 +48,48 @@
 		outb(inb_p(0x61) & 0xFC, 0x61);
 	}
 
-	spin_unlock_irqrestore(&i8253_beep_lock, flags);
+	spin_unlock_irqrestore(&i8253_lock, flags);
+}
+
+static int pcspkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
+{
+	unsigned int count = 0;
+
+	switch (type) {
+		case EV_SND:
+			switch (code) {
+				case SND_BELL: if (value) value = 1000;
+				case SND_TONE: break;
+				default: return -1;
+			}
+			break;
+
+		case EV_SYN:
+			switch (code) {
+				case SYN_CONFIG:
+					dev->state = value ? PCSPKR_SUSPENDED : PCSPKR_NORMAL;
+					return 0;
+				default: return -1;
+			}
+			break;
+
+		default: return -1;
+	}
+
+	if (dev->state == PCSPKR_SUSPENDED)
+		return 0;
+
+	if (value > 20 && value < 32767)
+		count = PIT_TICK_RATE / value;
+
+	pcspkr_do_sound(count);
 
 	return 0;
 }
 
 static int __init pcspkr_init(void)
 {
-	pcspkr_dev.evbit[0] = BIT(EV_SND);
+	pcspkr_dev.evbit[0] = BIT(EV_SND) | BIT(EV_SYN);
 	pcspkr_dev.sndbit[0] = BIT(SND_BELL) | BIT(SND_TONE);
 	pcspkr_dev.event = pcspkr_event;
 
@@ -78,6 +99,7 @@
 	pcspkr_dev.id.vendor = 0x001f;
 	pcspkr_dev.id.product = 0x0001;
 	pcspkr_dev.id.version = 0x0100;
+	pcspkr_dev.state = PCSPKR_NORMAL;
 
 	input_register_device(&pcspkr_dev);
 
@@ -90,7 +112,7 @@
 {
         input_unregister_device(&pcspkr_dev);
 	/* turn off the speaker */
-	pcspkr_event(NULL, EV_SND, SND_BELL, 0);
+	pcspkr_do_sound(0);
 }
 
 module_init(pcspkr_init);