[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.h b/sound/drivers/pcsp/pcsp.h
new file mode 100644
index 0000000..f07cc1e
--- /dev/null
+++ b/sound/drivers/pcsp/pcsp.h
@@ -0,0 +1,82 @@
+/*
+ * PC-Speaker driver for Linux
+ *
+ * Copyright (C) 1993-1997  Michael Beck
+ * Copyright (C) 1997-2001  David Woodhouse
+ * Copyright (C) 2001-2008  Stas Sergeev
+ */
+
+#ifndef __PCSP_H__
+#define __PCSP_H__
+
+#include <linux/hrtimer.h>
+#if defined(CONFIG_MIPS) || defined(CONFIG_X86)
+/* Use the global PIT lock ! */
+#include <asm/i8253.h>
+#else
+#include <asm/8253pit.h>
+static DEFINE_SPINLOCK(i8253_lock);
+#endif
+
+#define PCSP_SOUND_VERSION 0x400	/* read 4.00 */
+#define PCSP_DEBUG 0
+
+/* default timer freq for PC-Speaker: 18643 Hz */
+#define DIV_18KHZ 64
+#define MAX_DIV DIV_18KHZ
+#define CUR_DIV() (MAX_DIV >> chip->treble)
+#define PCSP_MAX_TREBLE 1
+
+/* unfortunately, with hrtimers 37KHz does not work very well :( */
+#define PCSP_DEFAULT_TREBLE 0
+#define MIN_DIV (MAX_DIV >> PCSP_MAX_TREBLE)
+
+/* wild guess */
+#define PCSP_MIN_LPJ 1000000
+#define PCSP_DEFAULT_SDIV (DIV_18KHZ >> 1)
+#define PCSP_DEFAULT_SRATE (PIT_TICK_RATE / PCSP_DEFAULT_SDIV)
+#define PCSP_INDEX_INC() (1 << (PCSP_MAX_TREBLE - chip->treble))
+#define PCSP_RATE() (PIT_TICK_RATE / CUR_DIV())
+#define PCSP_MIN_RATE__1 MAX_DIV/PIT_TICK_RATE
+#define PCSP_MAX_RATE__1 MIN_DIV/PIT_TICK_RATE
+#define PCSP_MAX_PERIOD_NS (1000000000ULL * PCSP_MIN_RATE__1)
+#define PCSP_MIN_PERIOD_NS (1000000000ULL * PCSP_MAX_RATE__1)
+#define PCSP_CALC_NS(div) ({ \
+	u64 __val = 1000000000ULL * (div); \
+	do_div(__val, PIT_TICK_RATE); \
+	__val; \
+})
+#define PCSP_PERIOD_NS() PCSP_CALC_NS(CUR_DIV())
+
+#define PCSP_MAX_PERIOD_SIZE	(64*1024)
+#define PCSP_MAX_PERIODS	512
+#define PCSP_BUFFER_SIZE	(128*1024)
+
+struct snd_pcsp {
+	struct snd_card *card;
+	struct snd_pcm *pcm;
+	struct input_dev *input_dev;
+	struct hrtimer timer;
+	unsigned short port, irq, dma;
+	spinlock_t substream_lock;
+	struct snd_pcm_substream *playback_substream;
+	size_t playback_ptr;
+	size_t period_ptr;
+	atomic_t timer_active;
+	int thalf;
+	u64 ns_rem;
+	unsigned char val61;
+	int enable;
+	int max_treble;
+	int treble;
+	int pcspkr;
+};
+
+extern struct snd_pcsp pcsp_chip;
+
+extern enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle);
+
+extern int snd_pcsp_new_pcm(struct snd_pcsp *chip);
+extern int snd_pcsp_new_mixer(struct snd_pcsp *chip);
+
+#endif