hal: Check input buffer size as multiple of channel
Update get input buffer size logic for record use cases
such that the size is also a multiple of bytes per sample
period. For 6 channel 32 bit recording the computed
value was not a multiple of bytes per sample and this
mismatches with the computed value by ALSA causing
buffer invalid errors because the use case pointers
difference was reaching stop threshold.
Change-Id: Ibca14baf26334888819cd15db39626b63c14f626
diff --git a/hal/audio_hw.c b/hal/audio_hw.c
index d35ff0d..8e62a02 100644
--- a/hal/audio_hw.c
+++ b/hal/audio_hw.c
@@ -3424,12 +3424,47 @@
"%s: stream can not declare supporting its sample rate %x", __func__, sample_rate);
}
+static inline uint32_t lcm(uint32_t num1, uint32_t num2)
+{
+ uint32_t high = num1, low = num2, temp = 0;
+
+ if (!num1 || !num2)
+ return 0;
+
+ if (num1 < num2) {
+ high = num2;
+ low = num1;
+ }
+
+ while (low != 0) {
+ temp = low;
+ low = high % low;
+ high = temp;
+ }
+ return (num1 * num2)/high;
+}
+
+static inline uint32_t nearest_multiple(uint32_t num, uint32_t multiplier)
+{
+ uint32_t remainder = 0;
+
+ if (!multiplier)
+ return num;
+
+ remainder = num % multiplier;
+ if (remainder)
+ num += (multiplier - remainder);
+
+ return num;
+}
+
static size_t get_input_buffer_size(uint32_t sample_rate,
audio_format_t format,
int channel_count,
bool is_low_latency)
{
size_t size = 0;
+ uint32_t bytes_per_period_sample = 0;
if (check_input_parameters(sample_rate, format, channel_count) != 0)
return 0;
@@ -3438,15 +3473,16 @@
if (is_low_latency)
size = configured_low_latency_capture_period_size;
- size *= audio_bytes_per_sample(format) * channel_count;
+ bytes_per_period_sample = audio_bytes_per_sample(format) * channel_count;
+ size *= bytes_per_period_sample;
/* make sure the size is multiple of 32 bytes
* At 48 kHz mono 16-bit PCM:
* 5.000 ms = 240 frames = 15*16*1*2 = 480, a whole multiple of 32 (15)
* 3.333 ms = 160 frames = 10*16*1*2 = 320, a whole multiple of 32 (10)
+ * Also, make sure the size is multiple of bytes per period sample
*/
- size += 0x1f;
- size &= ~0x1f;
+ size = nearest_multiple(size, lcm(32, bytes_per_period_sample));
return size;
}