[ALSA] Add PC-speaker sound driver

Added PC-speaker sound driver (snd-pcsp).

Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/drivers/pcsp/pcsp_input.c b/sound/drivers/pcsp/pcsp_input.c
new file mode 100644
index 0000000..cd9b83e
--- /dev/null
+++ b/sound/drivers/pcsp/pcsp_input.c
@@ -0,0 +1,116 @@
+/*
+ *  PC Speaker beeper driver for Linux
+ *
+ *  Copyright (c) 2002 Vojtech Pavlik
+ *  Copyright (c) 1992 Orest Zborowski
+ *
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation
+ */
+
+#include <linux/init.h>
+#include <linux/input.h>
+#include <asm/io.h>
+#include "pcsp.h"
+
+static void pcspkr_do_sound(unsigned int count)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&i8253_lock, flags);
+
+	if (count) {
+		/* enable counter 2 */
+		outb_p(inb_p(0x61) | 3, 0x61);
+		/* set command for counter 2, 2 byte write */
+		outb_p(0xB6, 0x43);
+		/* select desired HZ */
+		outb_p(count & 0xff, 0x42);
+		outb((count >> 8) & 0xff, 0x42);
+	} else {
+		/* disable counter 2 */
+		outb(inb_p(0x61) & 0xFC, 0x61);
+	}
+
+	spin_unlock_irqrestore(&i8253_lock, flags);
+}
+
+void pcspkr_stop_sound(void)
+{
+	pcspkr_do_sound(0);
+}
+
+static int pcspkr_input_event(struct input_dev *dev, unsigned int type,
+			      unsigned int code, int value)
+{
+	unsigned int count = 0;
+
+	if (atomic_read(&pcsp_chip.timer_active) || !pcsp_chip.pcspkr)
+		return 0;
+
+	switch (type) {
+	case EV_SND:
+		switch (code) {
+		case SND_BELL:
+			if (value)
+				value = 1000;
+		case SND_TONE:
+			break;
+		default:
+			return -1;
+		}
+		break;
+
+	default:
+		return -1;
+	}
+
+	if (value > 20 && value < 32767)
+		count = PIT_TICK_RATE / value;
+
+	pcspkr_do_sound(count);
+
+	return 0;
+}
+
+int __devinit pcspkr_input_init(struct input_dev **rdev, struct device *dev)
+{
+	int err;
+
+	struct input_dev *input_dev = input_allocate_device();
+	if (!input_dev)
+		return -ENOMEM;
+
+	input_dev->name = "PC Speaker";
+	input_dev->phys = "isa0061/input0";
+	input_dev->id.bustype = BUS_ISA;
+	input_dev->id.vendor = 0x001f;
+	input_dev->id.product = 0x0001;
+	input_dev->id.version = 0x0100;
+	input_dev->dev.parent = dev;
+
+	input_dev->evbit[0] = BIT(EV_SND);
+	input_dev->sndbit[0] = BIT(SND_BELL) | BIT(SND_TONE);
+	input_dev->event = pcspkr_input_event;
+
+	err = input_register_device(input_dev);
+	if (err) {
+		input_free_device(input_dev);
+		return err;
+	}
+
+	*rdev = input_dev;
+	return 0;
+}
+
+int pcspkr_input_remove(struct input_dev *dev)
+{
+	pcspkr_stop_sound();
+	input_unregister_device(dev);	/* this also does kfree() */
+
+	return 0;
+}