| /* |
| * 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; |
| } |