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authorAmaury Pouly <amaury.pouly@gmail.com>2017-02-23 11:33:19 +0100
committerAmaury Pouly <amaury.pouly@gmail.com>2017-09-05 21:42:12 +0200
commit1d121e8c082fe67757cf0d4df7b9e6ca1e26f755 (patch)
tree1c93842d99bb8e4a5f3ed5bca38c05e7f17894fa /firmware/target/hosted/pcm-alsa.c
parent142f80f07d96305f1618c99c28c13319b1b279e6 (diff)
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Initial commit for the Sony NWZ linux port
SUPPORTED SERIES: - NWZ-E450 - NWZ-E460 - NWZ-E470 - NWZ-E580 - NWZ-A10 NOTES: - bootloader makefile convert an extra font to be installed alongside the bootloader since sysfont is way too small - the toolsicon bitmap comes from the Oxygen iconset - touchscreen driver is untested TODO: - implement audio routing driver (pcm is handled by pcm-alsa) - fix playback: it crashes on illegal instruction in DEBUG builds - find out why the browser starts at / instead of /contents - implement radio support - implement return to OF for usb handling - calibrate battery curve (NB: of can report a battery level on a 0-5 scale but probabl don't want to use that ?) - implement simulator build (we need a nice image of the player) - figure out if we can detect jack removal POTENTIAL TODOS: - try to build a usb serial gadget and gdbserver Change-Id: Ic77d71e0651355d47cc4e423a40fb64a60c69a80
Diffstat (limited to 'firmware/target/hosted/pcm-alsa.c')
-rw-r--r--firmware/target/hosted/pcm-alsa.c89
1 files changed, 72 insertions, 17 deletions
diff --git a/firmware/target/hosted/pcm-alsa.c b/firmware/target/hosted/pcm-alsa.c
index 715af58fd9..d55eebccc1 100644
--- a/firmware/target/hosted/pcm-alsa.c
+++ b/firmware/target/hosted/pcm-alsa.c
@@ -50,12 +50,14 @@
#include "system.h"
#include "debug.h"
#include "kernel.h"
+#include "panic.h"
#include "pcm.h"
#include "pcm-internal.h"
#include "pcm_mixer.h"
#include "pcm_sampr.h"
#include "audiohw.h"
+#include "pcm-alsa.h"
#include <pthread.h>
#include <signal.h>
@@ -66,14 +68,21 @@
* with multple applications running */
static char device[] = "plughw:0,0"; /* playback device */
static const snd_pcm_access_t access_ = SND_PCM_ACCESS_RW_INTERLEAVED; /* access mode */
+#ifdef SONY_NWZ_LINUX
+/* Sony NWZ must use 32-bit per sample */
+static const snd_pcm_format_t format = SND_PCM_FORMAT_S32_LE; /* sample format */
+typedef long sample_t;
+#else
static const snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */
+typedef short sample_t;
+#endif
static const int channels = 2; /* count of channels */
static unsigned int rate = 44100; /* stream rate */
static snd_pcm_t *handle;
static snd_pcm_sframes_t buffer_size = MIX_FRAME_SAMPLES * 32; /* ~16k */
static snd_pcm_sframes_t period_size = MIX_FRAME_SAMPLES * 4; /* ~4k */
-static short *frames;
+static sample_t *frames;
static const void *pcm_data = 0;
static size_t pcm_size = 0;
@@ -153,7 +162,7 @@ static int set_hwparams(snd_pcm_t *handle, unsigned sample_rate)
goto error;
}
if (!frames)
- frames = malloc(period_size * channels * sizeof(short));
+ frames = malloc(period_size * channels * sizeof(sample_t));
/* write the parameters to device */
err = snd_pcm_hw_params(handle, params);
@@ -212,6 +221,40 @@ error:
return err;
}
+#ifdef SONY_NWZ_LINUX
+/* Digital volume explanation:
+ * with very good approximation (<0.1dB) the convertion from dB to multiplicative
+ * factor, for dB>=0, is 2^(dB/3). We can then notice that if we write dB=3*k+r
+ * then this is 2^k*2^(r/3) so we only need to look at r=0,1,2. For r=0 this is
+ * 1, for r=1 we have 2^(1/3)~=1.25 so we approximate by 1+1/4, and 2^(2/3)~=1.5
+ * so we approximate by 1+1/2. To go from negative to nonnegative we notice that
+ * 48 dB => 63095 factor ~= 2^16 so we virtually pre-multiply everything by 2^(-16)
+ * and add 48dB to the input volume. We cannot go lower -43dB because several
+ * values between -48dB and -43dB would require a fractional multiplier, which is
+ * stupid to implement for such very low volume. */
+static int dig_vol_mult = 2 ^ 16; /* multiplicative factor to apply to each sample */
+
+void pcm_alsa_set_digital_volume(int vol_db)
+{
+ if(vol_db > 0 || vol_db < -43)
+ panicf("invalid pcm alsa volume");
+ if(format != SND_PCM_FORMAT_S32_LE)
+ panicf("this function assumes 32-bit sample size");
+ vol_db += 48; /* -42dB .. 0dB => 5dB .. 48dB */
+ /* NOTE if vol_dB = 5 then vol_shift = 1 but r = 1 so we do vol_shift - 1 >= 0
+ * otherwise vol_dB >= 0 implies vol_shift >= 2 so vol_shift - 2 >= 0 */
+ int vol_shift = vol_db / 3;
+ int r = vol_db % 3;
+ if(r == 0)
+ dig_vol_mult = 1 << vol_shift;
+ else if(r == 1)
+ dig_vol_mult = 1 << vol_shift | 1 << (vol_shift - 2);
+ else
+ dig_vol_mult = 1 << vol_shift | 1 << (vol_shift - 1);
+ printf("%d dB -> factor = %d\n", vol_db - 48, dig_vol_mult);
+}
+#endif
+
/* copy pcm samples to a spare buffer, suitable for snd_pcm_writei() */
static bool fill_frames(void)
{
@@ -229,12 +272,28 @@ static bool fill_frames(void)
return false;
}
}
- copy_n = MIN((ssize_t)pcm_size, frames_left*4);
- memcpy(&frames[2*(period_size-frames_left)], pcm_data, copy_n);
- pcm_data += copy_n;
- pcm_size -= copy_n;
- frames_left -= copy_n/4;
+ if (pcm_size % 4)
+ panicf("Wrong pcm_size");
+ /* the compiler will optimize this test away */
+ copy_n = MIN((ssize_t)pcm_size/4, frames_left);
+ if (format == SND_PCM_FORMAT_S32_LE)
+ {
+ /* We have to convert 16-bit to 32-bit, the need to multiply the
+ * sample by some value so the sound is not too low */
+ const short *pcm_ptr = pcm_data;
+ sample_t *sample_ptr = &frames[2*(period_size-frames_left)];
+ for (int i = 0; i < copy_n*2; i++)
+ *sample_ptr++ = *pcm_ptr++ * dig_vol_mult;
+ }
+ else
+ {
+ /* Rockbox and PCM have same format: memcopy */
+ memcpy(&frames[2*(period_size-frames_left)], pcm_data, copy_n);
+ }
+ pcm_data += copy_n*4;
+ pcm_size -= copy_n*4;
+ frames_left -= copy_n;
if (new_buffer)
{
@@ -285,7 +344,7 @@ static int async_rw(snd_pcm_t *handle)
{
int err;
snd_pcm_sframes_t sample_size;
- short *samples;
+ sample_t *samples;
#ifdef USE_ASYNC_CALLBACK
/* assign alternative stack for the signal handlers */
@@ -323,7 +382,7 @@ static int async_rw(snd_pcm_t *handle)
/* fill buffer with silence to initiate playback without noisy click */
sample_size = buffer_size;
- samples = malloc(sample_size * channels * sizeof(short));
+ samples = malloc(sample_size * channels * sizeof(sample_t));
snd_pcm_format_set_silence(format, samples, sample_size);
err = snd_pcm_writei(handle, samples, sample_size);
@@ -367,23 +426,19 @@ void pcm_play_dma_init(void)
if ((err = snd_pcm_open(&handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0)
{
- printf("%s(): Cannot open device %s: %s\n", __func__, device, snd_strerror(err));
- exit(EXIT_FAILURE);
- return;
+ panicf("%s(): Cannot open device %s: %s\n", __func__, device, snd_strerror(err));
}
if ((err = snd_pcm_nonblock(handle, 1)))
- printf("Could not set non-block mode: %s\n", snd_strerror(err));
+ panicf("Could not set non-block mode: %s\n", snd_strerror(err));
if ((err = set_hwparams(handle, rate)) < 0)
{
- printf("Setting of hwparams failed: %s\n", snd_strerror(err));
- exit(EXIT_FAILURE);
+ panicf("Setting of hwparams failed: %s\n", snd_strerror(err));
}
if ((err = set_swparams(handle)) < 0)
{
- printf("Setting of swparams failed: %s\n", snd_strerror(err));
- exit(EXIT_FAILURE);
+ panicf("Setting of swparams failed: %s\n", snd_strerror(err));
}
pcm_dma_apply_settings();