[Alsa-devel] [PATCH] cs46xx fix problem when playbacking mono and 8 bit PCM

[Benny Sjostrand]

The current cs46xx driver set's a incorrect DMA buffer size when playbacking, 8bit and mono pcm, that should be fixed by this patch.

(I'm still a newbie when it's about ALSA API stuffs, as I recently discovered the existence of SNDRV_PCM_HW_PARAM_PERIOD_BYTES and SNDRV_PCM_HW_PARAM_PERIOD_SIZE parameters ...)

/Benny

--- alsa-kernel/pci/cs46xx/cs46xx_lib.c Sat Jan  4 23:46:27 2003
+++ ../cvs/alsa-kernel/pci/cs46xx/cs46xx_lib.c  Sun Jan  5 00:48:56 2003
@@ -26,7 +26,7 @@
  *           at Cirrus for have helping me out with the DSP, however we
  *           still dont have sufficient documentation and technical
  *           references to be able to implement all fancy feutures
- *           supported by the cs46xx DPS's. 
+ *           supported by the cs46xx DSP's. 
  *           Benny <[EMAIL PROTECTED]>
  *                
  *   This program is free software; you can redistribute it and/or modify
@@ -57,6 +57,8 @@
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/info.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
 #include <sound/cs46xx.h>
 
 #include <asm/io.h>
@@ -730,10 +732,12 @@
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_sframes_t diff;
        cs46xx_pcm_t * cpcm;
-       int buffer_size = runtime->period_size * CS46XX_FRAGS * 4;
+       int buffer_size;
 
        cpcm = snd_magic_cast(cs46xx_pcm_t, substream->runtime->private_data, return 
-ENXIO);
 
+       buffer_size = runtime->period_size * CS46XX_FRAGS << cpcm->shift;
+
        diff = runtime->control->appl_ptr - cpcm->appl_ptr;
        if (diff) {
                if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
@@ -774,7 +778,7 @@
        cs46xx_t *chip = snd_pcm_substream_chip(substream);
        snd_pcm_runtime_t *runtime = substream->runtime;
        snd_pcm_sframes_t diff = runtime->control->appl_ptr - chip->capt.appl_ptr;
-       int buffer_size = runtime->period_size * CS46XX_FRAGS * 4;
+       int buffer_size = runtime->period_size * CS46XX_FRAGS << chip->capt.shift;
        if (diff) {
                if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
                        diff += runtime->boundary;
@@ -830,7 +834,7 @@
        size_t ptr;
        cs46xx_pcm_t *cpcm = snd_magic_cast(cs46xx_pcm_t, 
substream->runtime->private_data, return -ENXIO);
        ssize_t bytes;
-       int buffer_size = substream->runtime->period_size * CS46XX_FRAGS * 4;
+       int buffer_size = substream->runtime->period_size * CS46XX_FRAGS << 
+cpcm->shift;
 
 #ifdef CONFIG_SND_CS46XX_NEW_DSP
        snd_assert (cpcm->pcm_channel,return -ENXIO);
@@ -865,7 +869,7 @@
        cs46xx_t *chip = snd_pcm_substream_chip(substream);
        size_t ptr = snd_cs46xx_peek(chip, BA1_CBA) - chip->capt.hw_addr;
        ssize_t bytes = ptr - chip->capt.hw_io;
-       int buffer_size = substream->runtime->period_size * CS46XX_FRAGS * 4;
+       int buffer_size = substream->runtime->period_size * CS46XX_FRAGS << 
+chip->capt.shift;
 
        if (bytes < 0)
                bytes += buffer_size;
@@ -1071,7 +1075,7 @@
        int err;
        cs46xx_t *chip = snd_pcm_substream_chip(substream);
        int sample_rate = params_rate(hw_params);
-       int period_size = params_period_size(hw_params);
+       int period_size = params_period_bytes(hw_params);
        cpcm = snd_magic_cast(cs46xx_pcm_t, runtime->private_data, return -ENXIO);
 
 #ifdef CONFIG_SND_CS46XX_NEW_DSP
@@ -1090,12 +1094,15 @@
                return -ENXIO;
        }
 
-       if (cs46xx_dsp_pcm_channel_set_period (chip,cpcm->pcm_channel,period_size * 
4)) {
+
+       if (cs46xx_dsp_pcm_channel_set_period (chip,cpcm->pcm_channel,period_size)) {
                 up (&chip->spos_mutex);
                 return -EINVAL;
         }
-       snd_printdd ("period_size (%d), periods (%d)\n",
-                    period_size, params_periods(hw_params));
+
+       snd_printdd ("period_size (%d), periods (%d) buffer_size(%d)\n",
+                    period_size, params_periods(hw_params),
+                    params_buffer_bytes(hw_params));
 #endif
 
        if (params_periods(hw_params) == CS46XX_FRAGS) {
@@ -1256,11 +1263,14 @@
        snd_pcm_runtime_t *runtime = substream->runtime;
        int err;
        int period_size = params_period_size(hw_params);
+       int factor;
 
 #ifdef CONFIG_SND_CS46XX_NEW_DSP
        snd_printdd ("capture period size (%d)\n",period_size);
+       
+       factor = (runtime->periods == CS46XX_FRAGS) ? CS46XX_FRAGS : (CS46XX_FRAGS * 
+2);
 
-       cs46xx_dsp_pcm_ostream_set_period (chip,period_size * 4);
+       cs46xx_dsp_pcm_ostream_set_period (chip,period_size * factor);
 #endif
        if (runtime->periods == CS46XX_FRAGS) {
                if (runtime->dma_area != chip->capt.hw_area)
@@ -1445,7 +1455,7 @@
        .fifo_size =            0,
 };
 
-static unsigned int period_sizes[] = { 8, 16, 32, 64, 128, 256, 512 };
+static unsigned int period_sizes[] = { 32, 64, 128, 256, 512, 1024, 2048 };
 
 #define PERIOD_SIZES sizeof(period_sizes) / sizeof(period_sizes[0])
 
@@ -1488,8 +1498,11 @@
        cpcm->pcm_channel = NULL; 
        cpcm->pcm_channel_id = pcm_channel_id;
 
-       snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
+
+       snd_pcm_hw_constraint_list(runtime, 0,
+                                  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 
                                   &hw_constraints_period_sizes);
+
        up (&chip->spos_mutex);
 #else
        chip->playback_pcm = cpcm; /* HACK */
@@ -1565,7 +1578,8 @@
        chip->amplifier_ctrl(chip, 1);
 
 #ifdef CONFIG_SND_CS46XX_NEW_DSP
-       snd_pcm_hw_constraint_list(substream->runtime, 0, 
SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 
+       snd_pcm_hw_constraint_list(substream->runtime, 0,
+                                  SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 
                                   &hw_constraints_period_sizes);
 #endif
        return 0;