|  | /* | 
|  | * 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/moduleparam.h> | 
|  | #include <sound/pcm.h> | 
|  | #include <asm/io.h> | 
|  | #include "pcsp.h" | 
|  |  | 
|  | static int 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 | 
|  |  | 
|  | enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle) | 
|  | { | 
|  | unsigned char timer_cnt, val; | 
|  | int fmt_size, periods_elapsed; | 
|  | u64 ns; | 
|  | size_t period_bytes, buffer_bytes; | 
|  | struct snd_pcm_substream *substream; | 
|  | struct snd_pcm_runtime *runtime; | 
|  | struct snd_pcsp *chip = container_of(handle, struct snd_pcsp, timer); | 
|  |  | 
|  | if (chip->thalf) { | 
|  | outb(chip->val61, 0x61); | 
|  | chip->thalf = 0; | 
|  | if (!atomic_read(&chip->timer_active)) | 
|  | return HRTIMER_NORESTART; | 
|  | hrtimer_forward(&chip->timer, hrtimer_get_expires(&chip->timer), | 
|  | ktime_set(0, chip->ns_rem)); | 
|  | return HRTIMER_RESTART; | 
|  | } | 
|  |  | 
|  | spin_lock_irq(&chip->substream_lock); | 
|  | /* Takashi Iwai says regarding this extra lock: | 
|  |  | 
|  | If the irq handler handles some data on the DMA buffer, it should | 
|  | do snd_pcm_stream_lock(). | 
|  | That protects basically against all races among PCM callbacks, yes. | 
|  | However, there are two remaining issues: | 
|  | 1. The substream pointer you try to lock isn't protected _before_ | 
|  | this lock yet. | 
|  | 2. snd_pcm_period_elapsed() itself acquires the lock. | 
|  | The requirement of another lock is because of 1.  When you get | 
|  | chip->playback_substream, it's not protected. | 
|  | Keeping this lock while snd_pcm_period_elapsed() assures the substream | 
|  | is still protected (at least, not released).  And the other status is | 
|  | handled properly inside snd_pcm_stream_lock() in | 
|  | snd_pcm_period_elapsed(). | 
|  |  | 
|  | */ | 
|  | if (!chip->playback_substream) | 
|  | goto exit_nr_unlock1; | 
|  | substream = chip->playback_substream; | 
|  | snd_pcm_stream_lock(substream); | 
|  | if (!atomic_read(&chip->timer_active)) | 
|  | goto exit_nr_unlock2; | 
|  |  | 
|  | runtime = substream->runtime; | 
|  | fmt_size = snd_pcm_format_physical_width(runtime->format) >> 3; | 
|  | /* assume it is mono! */ | 
|  | val = runtime->dma_area[chip->playback_ptr + fmt_size - 1]; | 
|  | if (snd_pcm_format_signed(runtime->format)) | 
|  | val ^= 0x80; | 
|  | timer_cnt = val * CUR_DIV() / 256; | 
|  |  | 
|  | if (timer_cnt && chip->enable) { | 
|  | spin_lock(&i8253_lock); | 
|  | 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; | 
|  | } | 
|  | spin_unlock(&i8253_lock); | 
|  | } | 
|  |  | 
|  | period_bytes = snd_pcm_lib_period_bytes(substream); | 
|  | buffer_bytes = snd_pcm_lib_buffer_bytes(substream); | 
|  | chip->playback_ptr += PCSP_INDEX_INC() * 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; | 
|  |  | 
|  | snd_pcm_stream_unlock(substream); | 
|  |  | 
|  | if (periods_elapsed) { | 
|  | snd_pcm_period_elapsed(substream); | 
|  | chip->period_ptr += periods_elapsed * period_bytes; | 
|  | chip->period_ptr %= buffer_bytes; | 
|  | } | 
|  |  | 
|  | spin_unlock_irq(&chip->substream_lock); | 
|  |  | 
|  | if (!atomic_read(&chip->timer_active)) | 
|  | return HRTIMER_NORESTART; | 
|  |  | 
|  | chip->ns_rem = PCSP_PERIOD_NS(); | 
|  | ns = (chip->thalf ? PCSP_CALC_NS(timer_cnt) : chip->ns_rem); | 
|  | chip->ns_rem -= ns; | 
|  | hrtimer_forward(&chip->timer, hrtimer_get_expires(&chip->timer), | 
|  | ktime_set(0, ns)); | 
|  | return HRTIMER_RESTART; | 
|  |  | 
|  | exit_nr_unlock2: | 
|  | snd_pcm_stream_unlock(substream); | 
|  | exit_nr_unlock1: | 
|  | spin_unlock_irq(&chip->substream_lock); | 
|  | return HRTIMER_NORESTART; | 
|  | } | 
|  |  | 
|  | static void 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; | 
|  | } | 
|  |  | 
|  | spin_lock(&i8253_lock); | 
|  | chip->val61 = inb(0x61) | 0x03; | 
|  | outb_p(0x92, 0x43);	/* binary, mode 1, LSB only, ch 2 */ | 
|  | spin_unlock(&i8253_lock); | 
|  | atomic_set(&chip->timer_active, 1); | 
|  | chip->thalf = 0; | 
|  |  | 
|  | hrtimer_start(&pcsp_chip.timer, ktime_set(0, 0), HRTIMER_MODE_REL); | 
|  | } | 
|  |  | 
|  | 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); | 
|  | spin_lock(&i8253_lock); | 
|  | /* restore the timer */ | 
|  | outb_p(0xb6, 0x43);	/* binary, mode 3, LSB/MSB, ch 2 */ | 
|  | outb(chip->val61 & 0xFC, 0x61); | 
|  | spin_unlock(&i8253_lock); | 
|  | } | 
|  |  | 
|  | 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 | 
|  | if (atomic_read(&chip->timer_active)) { | 
|  | printk(KERN_ERR "PCSP: timer still active\n"); | 
|  | pcsp_stop_playing(chip); | 
|  | } | 
|  | spin_lock_irq(&chip->substream_lock); | 
|  | chip->playback_substream = NULL; | 
|  | spin_unlock_irq(&chip->substream_lock); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int snd_pcsp_playback_hw_params(struct snd_pcm_substream *substream, | 
|  | struct snd_pcm_hw_params *hw_params) | 
|  | { | 
|  | int err; | 
|  | 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) | 
|  | { | 
|  | #if PCSP_DEBUG | 
|  | printk(KERN_INFO "PCSP: hw_free called\n"); | 
|  | #endif | 
|  | 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); | 
|  | #if PCSP_DEBUG | 
|  | printk(KERN_INFO "PCSP: prepare called, " | 
|  | "size=%zi psize=%zi f=%zi f1=%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); | 
|  | #endif | 
|  | chip->playback_ptr = 0; | 
|  | chip->period_ptr = 0; | 
|  | 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: | 
|  | pcsp_start_playing(chip); | 
|  | break; | 
|  | 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); | 
|  | return bytes_to_frames(substream->runtime, chip->playback_ptr); | 
|  | } | 
|  |  | 
|  | static 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; | 
|  | spin_lock_irq(&chip->substream_lock); | 
|  | chip->playback_substream = substream; | 
|  | spin_unlock_irq(&chip->substream_lock); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static 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 __devinit 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; | 
|  | } |