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[media] msi3101: implement stream format 504

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That stream format carries 504 x I+Q samples per 1024 USB frame.
Sample resolution is 8-bit signed. Default it when sampling rate
is 9Msps or over.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This commit is contained in:
Antti Palosaari 2013-08-08 15:39:33 -03:00 • committed by Mauro Carvalho Chehab
commit 61198dfd08
1 changed files with 92 additions and 2 deletions
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94
drivers/staging/media/msi3101/sdr-msi3101.c
View file

@ -448,7 +448,7 @@ leave:
/*
* +===========================================================================
* | 00-1023 | USB packet
* | 00-1023 | USB packet type '384'
* +===========================================================================
* | 00- 03 | sequence number of first sample in that USB packet
* +---------------------------------------------------------------------------
@ -501,6 +501,93 @@ leave:
#define I2F_FRAC_BITS 23
#define I2F_MASK ((1 << I2F_FRAC_BITS) - 1)
/*
* Converts signed 8-bit integer into 32-bit IEEE floating point
* representation.
*/
static u32 msi3101_convert_sample_504(struct msi3101_state *s, u16 x)
{
u32 msb, exponent, fraction, sign;
/* Zero is special */
if (!x)
return 0;
/* Negative / positive value */
if (x & (1 << 7)) {
x = -x;
x &= 0x7f; /* result is 7 bit ... + sign */
sign = 1 << 31;
} else {
sign = 0 << 31;
}
/* Get location of the most significant bit */
msb = __fls(x);
fraction = ror32(x, (msb - I2F_FRAC_BITS) & 0x1f) & I2F_MASK;
exponent = (127 + msb) << I2F_FRAC_BITS;
return (fraction + exponent) | sign;
}
static int msi3101_convert_stream_504(struct msi3101_state *s, u32 *dst,
u8 *src, unsigned int src_len)
{
int i, j, i_max, dst_len = 0;
u16 sample[2];
u32 sample_num[3];
/* There could be 1-3 1024 bytes URB frames */
i_max = src_len / 1024;
for (i = 0; i < i_max; i++) {
sample_num[i] = src[3] << 24 | src[2] << 16 | src[1] << 8 | src[0] << 0;
if (i == 0 && s->next_sample != sample_num[0]) {
dev_dbg_ratelimited(&s->udev->dev,
"%d samples lost, %d %08x:%08x\n",
sample_num[0] - s->next_sample,
src_len, s->next_sample, sample_num[0]);
}
/*
* Dump all unknown 'garbage' data - maybe we will discover
* someday if there is something rational...
*/
dev_dbg_ratelimited(&s->udev->dev, "%*ph\n", 12, &src[4]);
src += 16;
for (j = 0; j < 1008; j += 2) {
sample[0] = src[j + 0];
sample[1] = src[j + 1];
*dst++ = msi3101_convert_sample_504(s, sample[0]);
*dst++ = msi3101_convert_sample_504(s, sample[1]);
}
/* 504 x I+Q 32bit float samples */
dst_len += 504 * 2 * 4;
src += 1008;
}
/* calculate samping rate and output it in 10 seconds intervals */
if ((s->jiffies + msecs_to_jiffies(10000)) <= jiffies) {
unsigned long jiffies_now = jiffies;
unsigned long msecs = jiffies_to_msecs(jiffies_now) - jiffies_to_msecs(s->jiffies);
unsigned int samples = sample_num[i_max - 1] - s->sample;
s->jiffies = jiffies_now;
s->sample = sample_num[i_max - 1];
dev_dbg(&s->udev->dev,
"slen=%d samples=%u msecs=%lu sampling rate=%lu\n",
src_len, samples, msecs,
samples * 1000UL / msecs);
}
/* next sample (sample = sample + i * 504) */
s->next_sample = sample_num[i_max - 1] + 504;
return dst_len;
}
/*
* Converts signed ~10+3-bit integer into 32-bit IEEE floating point
* representation.
@ -1134,9 +1221,12 @@ static int msi3101_set_usb_adc(struct msi3101_state *s)
} else if (f_sr < 8000000) {
s->convert_stream = msi3101_convert_stream_336;
reg7 = 0x00008507;
} else {
} else if (f_sr < 9000000) {
s->convert_stream = msi3101_convert_stream_384;
reg7 = 0x0000a507;
} else {
s->convert_stream = msi3101_convert_stream_504;
reg7 = 0x000c9407;
}
/*