1 files changed, 360 insertions, 0 deletions
diff --git a/sound/drivers/pcsp/pcsp_lib.c b/sound/drivers/pcsp/pcsp_lib.c
new file mode 100644
index 000000000..8f0f05bbc
--- /dev/null
+++ b/sound/drivers/pcsp/pcsp_lib.c
@@ -0,0 +1,360 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PC-Speaker driver for Linux
+ *
+ * Copyright (C) 1993-1997  Michael Beck
+ * Copyright (C) 1997-2001  David Woodhouse
+ * Copyright (C) 2001-2008  Stas Sergeev
+ */
+
+#include <linux/module.h>
+#include <linux/gfp.h>
+#include <linux/moduleparam.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <sound/pcm.h>
+#include "pcsp.h"
+
+static bool nforce_wa;
+module_param(nforce_wa, bool, 0444);
+MODULE_PARM_DESC(nforce_wa, "Apply NForce chipset workaround "
+		"(expect bad sound)");
+
+#define DMIX_WANTS_S16	1
+
+/*
+ * Call snd_pcm_period_elapsed in a tasklet
+ * This avoids spinlock messes and long-running irq contexts
+ */
+static void pcsp_call_pcm_elapsed(unsigned long priv)
+{
+	if (atomic_read(&pcsp_chip.timer_active)) {
+		struct snd_pcm_substream *substream;
+		substream = pcsp_chip.playback_substream;
+		if (substream)
+			snd_pcm_period_elapsed(substream);
+	}
+}
+
+static DECLARE_TASKLET(pcsp_pcm_tasklet, pcsp_call_pcm_elapsed, 0);
+
+/* write the port and returns the next expire time in ns;
+ * called at the trigger-start and in hrtimer callback
+ */
+static u64 pcsp_timer_update(struct snd_pcsp *chip)
+{
+	unsigned char timer_cnt, val;
+	u64 ns;
+	struct snd_pcm_substream *substream;
+	struct snd_pcm_runtime *runtime;
+	unsigned long flags;
+
+	if (chip->thalf) {
+		outb(chip->val61, 0x61);
+		chip->thalf = 0;
+		return chip->ns_rem;
+	}
+
+	substream = chip->playback_substream;
+	if (!substream)
+		return 0;
+
+	runtime = substream->runtime;
+	/* assume it is mono! */
+	val = runtime->dma_area[chip->playback_ptr + chip->fmt_size - 1];
+	if (chip->is_signed)
+		val ^= 0x80;
+	timer_cnt = val * CUR_DIV() / 256;
+
+	if (timer_cnt && chip->enable) {
+		raw_spin_lock_irqsave(&i8253_lock, flags);
+		if (!nforce_wa) {
+			outb_p(chip->val61, 0x61);
+			outb_p(timer_cnt, 0x42);
+			outb(chip->val61 ^ 1, 0x61);
+		} else {
+			outb(chip->val61 ^ 2, 0x61);
+			chip->thalf = 1;
+		}
+		raw_spin_unlock_irqrestore(&i8253_lock, flags);
+	}
+
+	chip->ns_rem = PCSP_PERIOD_NS();
+	ns = (chip->thalf ? PCSP_CALC_NS(timer_cnt) : chip->ns_rem);
+	chip->ns_rem -= ns;
+	return ns;
+}
+
+static void pcsp_pointer_update(struct snd_pcsp *chip)
+{
+	struct snd_pcm_substream *substream;
+	size_t period_bytes, buffer_bytes;
+	int periods_elapsed;
+	unsigned long flags;
+
+	/* update the playback position */
+	substream = chip->playback_substream;
+	if (!substream)
+		return;
+
+	period_bytes = snd_pcm_lib_period_bytes(substream);
+	buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
+
+	spin_lock_irqsave(&chip->substream_lock, flags);
+	chip->playback_ptr += PCSP_INDEX_INC() * chip->fmt_size;
+	periods_elapsed = chip->playback_ptr - chip->period_ptr;
+	if (periods_elapsed < 0) {
+#if PCSP_DEBUG
+		printk(KERN_INFO "PCSP: buffer_bytes mod period_bytes != 0 ? "
+			"(%zi %zi %zi)\n",
+			chip->playback_ptr, period_bytes, buffer_bytes);
+#endif
+		periods_elapsed += buffer_bytes;
+	}
+	periods_elapsed /= period_bytes;
+	/* wrap the pointer _before_ calling snd_pcm_period_elapsed(),
+	 * or ALSA will BUG on us. */
+	chip->playback_ptr %= buffer_bytes;
+
+	if (periods_elapsed) {
+		chip->period_ptr += periods_elapsed * period_bytes;
+		chip->period_ptr %= buffer_bytes;
+	}
+	spin_unlock_irqrestore(&chip->substream_lock, flags);
+
+	if (periods_elapsed)
+		tasklet_schedule(&pcsp_pcm_tasklet);
+}
+
+enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle)
+{
+	struct snd_pcsp *chip = container_of(handle, struct snd_pcsp, timer);
+	int pointer_update;
+	u64 ns;
+
+	if (!atomic_read(&chip->timer_active) || !chip->playback_substream)
+		return HRTIMER_NORESTART;
+
+	pointer_update = !chip->thalf;
+	ns = pcsp_timer_update(chip);
+	if (!ns) {
+		printk(KERN_WARNING "PCSP: unexpected stop\n");
+		return HRTIMER_NORESTART;
+	}
+
+	if (pointer_update)
+		pcsp_pointer_update(chip);
+
+	hrtimer_forward(handle, hrtimer_get_expires(handle), ns_to_ktime(ns));
+
+	return HRTIMER_RESTART;
+}
+
+static int pcsp_start_playing(struct snd_pcsp *chip)
+{
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: start_playing called\n");
+#endif
+	if (atomic_read(&chip->timer_active)) {
+		printk(KERN_ERR "PCSP: Timer already active\n");
+		return -EIO;
+	}
+
+	raw_spin_lock(&i8253_lock);
+	chip->val61 = inb(0x61) | 0x03;
+	outb_p(0x92, 0x43);	/* binary, mode 1, LSB only, ch 2 */
+	raw_spin_unlock(&i8253_lock);
+	atomic_set(&chip->timer_active, 1);
+	chip->thalf = 0;
+
+	hrtimer_start(&pcsp_chip.timer, 0, HRTIMER_MODE_REL);
+	return 0;
+}
+
+static void pcsp_stop_playing(struct snd_pcsp *chip)
+{
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: stop_playing called\n");
+#endif
+	if (!atomic_read(&chip->timer_active))
+		return;
+
+	atomic_set(&chip->timer_active, 0);
+	raw_spin_lock(&i8253_lock);
+	/* restore the timer */
+	outb_p(0xb6, 0x43);	/* binary, mode 3, LSB/MSB, ch 2 */
+	outb(chip->val61 & 0xFC, 0x61);
+	raw_spin_unlock(&i8253_lock);
+}
+
+/*
+ * Force to stop and sync the stream
+ */
+void pcsp_sync_stop(struct snd_pcsp *chip)
+{
+	local_irq_disable();
+	pcsp_stop_playing(chip);
+	local_irq_enable();
+	hrtimer_cancel(&chip->timer);
+	tasklet_kill(&pcsp_pcm_tasklet);
+}
+
+static int snd_pcsp_playback_close(struct snd_pcm_substream *substream)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: close called\n");
+#endif
+	pcsp_sync_stop(chip);
+	chip->playback_substream = NULL;
+	return 0;
+}
+
+static int snd_pcsp_playback_hw_params(struct snd_pcm_substream *substream,
+				       struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+	int err;
+	pcsp_sync_stop(chip);
+	err = snd_pcm_lib_malloc_pages(substream,
+				      params_buffer_bytes(hw_params));
+	if (err < 0)
+		return err;
+	return 0;
+}
+
+static int snd_pcsp_playback_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: hw_free called\n");
+#endif
+	pcsp_sync_stop(chip);
+	return snd_pcm_lib_free_pages(substream);
+}
+
+static int snd_pcsp_playback_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+	pcsp_sync_stop(chip);
+	chip->playback_ptr = 0;
+	chip->period_ptr = 0;
+	chip->fmt_size =
+		snd_pcm_format_physical_width(substream->runtime->format) >> 3;
+	chip->is_signed = snd_pcm_format_signed(substream->runtime->format);
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: prepare called, "
+			"size=%zi psize=%zi f=%zi f1=%i fsize=%i\n",
+			snd_pcm_lib_buffer_bytes(substream),
+			snd_pcm_lib_period_bytes(substream),
+			snd_pcm_lib_buffer_bytes(substream) /
+			snd_pcm_lib_period_bytes(substream),
+			substream->runtime->periods,
+			chip->fmt_size);
+#endif
+	return 0;
+}
+
+static int snd_pcsp_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: trigger called\n");
+#endif
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		return pcsp_start_playing(chip);
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		pcsp_stop_playing(chip);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static snd_pcm_uframes_t snd_pcsp_playback_pointer(struct snd_pcm_substream
+						   *substream)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+	unsigned int pos;
+	spin_lock(&chip->substream_lock);
+	pos = chip->playback_ptr;
+	spin_unlock(&chip->substream_lock);
+	return bytes_to_frames(substream->runtime, pos);
+}
+
+static const struct snd_pcm_hardware snd_pcsp_playback = {
+	.info = (SNDRV_PCM_INFO_INTERLEAVED |
+		 SNDRV_PCM_INFO_HALF_DUPLEX |
+		 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID),
+	.formats = (SNDRV_PCM_FMTBIT_U8
+#if DMIX_WANTS_S16
+		    | SNDRV_PCM_FMTBIT_S16_LE
+#endif
+	    ),
+	.rates = SNDRV_PCM_RATE_KNOT,
+	.rate_min = PCSP_DEFAULT_SRATE,
+	.rate_max = PCSP_DEFAULT_SRATE,
+	.channels_min = 1,
+	.channels_max = 1,
+	.buffer_bytes_max = PCSP_BUFFER_SIZE,
+	.period_bytes_min = 64,
+	.period_bytes_max = PCSP_MAX_PERIOD_SIZE,
+	.periods_min = 2,
+	.periods_max = PCSP_MAX_PERIODS,
+	.fifo_size = 0,
+};
+
+static int snd_pcsp_playback_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
+#if PCSP_DEBUG
+	printk(KERN_INFO "PCSP: open called\n");
+#endif
+	if (atomic_read(&chip->timer_active)) {
+		printk(KERN_ERR "PCSP: still active!!\n");
+		return -EBUSY;
+	}
+	runtime->hw = snd_pcsp_playback;
+	chip->playback_substream = substream;
+	return 0;
+}
+
+static const struct snd_pcm_ops snd_pcsp_playback_ops = {
+	.open = snd_pcsp_playback_open,
+	.close = snd_pcsp_playback_close,
+	.ioctl = snd_pcm_lib_ioctl,
+	.hw_params = snd_pcsp_playback_hw_params,
+	.hw_free = snd_pcsp_playback_hw_free,
+	.prepare = snd_pcsp_playback_prepare,
+	.trigger = snd_pcsp_trigger,
+	.pointer = snd_pcsp_playback_pointer,
+};
+
+int snd_pcsp_new_pcm(struct snd_pcsp *chip)
+{
+	int err;
+
+	err = snd_pcm_new(chip->card, "pcspeaker", 0, 1, 0, &chip->pcm);
+	if (err < 0)
+		return err;
+
+	snd_pcm_set_ops(chip->pcm, SNDRV_PCM_STREAM_PLAYBACK,
+			&snd_pcsp_playback_ops);
+
+	chip->pcm->private_data = chip;
+	chip->pcm->info_flags = SNDRV_PCM_INFO_HALF_DUPLEX;
+	strcpy(chip->pcm->name, "pcsp");
+
+	snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
+					      SNDRV_DMA_TYPE_CONTINUOUS,
+					      snd_dma_continuous_data
+					      (GFP_KERNEL), PCSP_BUFFER_SIZE,
+					      PCSP_BUFFER_SIZE);
+
+	return 0;
+}