[PATCH v2 4/4] ASoC: nau8825: Replace copied'n'pasted intlog10()

Andy Shevchenko
2023-07-03T13:52:41Z

As the code even references to dvb_math.c, which is now available
as int_log.c, replace its content by the calling respective API.

Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/20230619172019.21457-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
sound/soc/codecs/nau8825.c | 93 ++------------------------------------
1 file changed, 3 insertions(+), 90 deletions(-)

diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c
index 9e0e4ddf128e..5cb0de648bd3 100644
--- a/sound/soc/codecs/nau8825.c
+++ b/sound/soc/codecs/nau8825.c
@@ -11,6 +11,7 @@
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
+#include <linux/int_log.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/slab.h>
@@ -38,7 +39,6 @@
#define NAU_FVCO_MIN 90000000

/* cross talk suppression detection */
-#define LOG10_MAGIC 646456993
#define GAIN_AUGMENT 22500
#define SIDETONE_BASE 207000

@@ -219,42 +219,6 @@ static const struct reg_sequence nau8825_regmap_patch[] = {
{ NAU8825_REG_MIC_BIAS, 0x0046 },
};

-
-static const unsigned short logtable[256] = {
- 0x0000, 0x0171, 0x02e0, 0x044e, 0x05ba, 0x0725, 0x088e, 0x09f7,
- 0x0b5d, 0x0cc3, 0x0e27, 0x0f8a, 0x10eb, 0x124b, 0x13aa, 0x1508,
- 0x1664, 0x17bf, 0x1919, 0x1a71, 0x1bc8, 0x1d1e, 0x1e73, 0x1fc6,
- 0x2119, 0x226a, 0x23ba, 0x2508, 0x2656, 0x27a2, 0x28ed, 0x2a37,
- 0x2b80, 0x2cc8, 0x2e0f, 0x2f54, 0x3098, 0x31dc, 0x331e, 0x345f,
- 0x359f, 0x36de, 0x381b, 0x3958, 0x3a94, 0x3bce, 0x3d08, 0x3e41,
- 0x3f78, 0x40af, 0x41e4, 0x4319, 0x444c, 0x457f, 0x46b0, 0x47e1,
- 0x4910, 0x4a3f, 0x4b6c, 0x4c99, 0x4dc5, 0x4eef, 0x5019, 0x5142,
- 0x526a, 0x5391, 0x54b7, 0x55dc, 0x5700, 0x5824, 0x5946, 0x5a68,
- 0x5b89, 0x5ca8, 0x5dc7, 0x5ee5, 0x6003, 0x611f, 0x623a, 0x6355,
- 0x646f, 0x6588, 0x66a0, 0x67b7, 0x68ce, 0x69e4, 0x6af8, 0x6c0c,
- 0x6d20, 0x6e32, 0x6f44, 0x7055, 0x7165, 0x7274, 0x7383, 0x7490,
- 0x759d, 0x76aa, 0x77b5, 0x78c0, 0x79ca, 0x7ad3, 0x7bdb, 0x7ce3,
- 0x7dea, 0x7ef0, 0x7ff6, 0x80fb, 0x81ff, 0x8302, 0x8405, 0x8507,
- 0x8608, 0x8709, 0x8809, 0x8908, 0x8a06, 0x8b04, 0x8c01, 0x8cfe,
- 0x8dfa, 0x8ef5, 0x8fef, 0x90e9, 0x91e2, 0x92db, 0x93d2, 0x94ca,
- 0x95c0, 0x96b6, 0x97ab, 0x98a0, 0x9994, 0x9a87, 0x9b7a, 0x9c6c,
- 0x9d5e, 0x9e4f, 0x9f3f, 0xa02e, 0xa11e, 0xa20c, 0xa2fa, 0xa3e7,
- 0xa4d4, 0xa5c0, 0xa6ab, 0xa796, 0xa881, 0xa96a, 0xaa53, 0xab3c,
- 0xac24, 0xad0c, 0xadf2, 0xaed9, 0xafbe, 0xb0a4, 0xb188, 0xb26c,
- 0xb350, 0xb433, 0xb515, 0xb5f7, 0xb6d9, 0xb7ba, 0xb89a, 0xb97a,
- 0xba59, 0xbb38, 0xbc16, 0xbcf4, 0xbdd1, 0xbead, 0xbf8a, 0xc065,
- 0xc140, 0xc21b, 0xc2f5, 0xc3cf, 0xc4a8, 0xc580, 0xc658, 0xc730,
- 0xc807, 0xc8de, 0xc9b4, 0xca8a, 0xcb5f, 0xcc34, 0xcd08, 0xcddc,
- 0xceaf, 0xcf82, 0xd054, 0xd126, 0xd1f7, 0xd2c8, 0xd399, 0xd469,
- 0xd538, 0xd607, 0xd6d6, 0xd7a4, 0xd872, 0xd93f, 0xda0c, 0xdad9,
- 0xdba5, 0xdc70, 0xdd3b, 0xde06, 0xded0, 0xdf9a, 0xe063, 0xe12c,
- 0xe1f5, 0xe2bd, 0xe385, 0xe44c, 0xe513, 0xe5d9, 0xe69f, 0xe765,
- 0xe82a, 0xe8ef, 0xe9b3, 0xea77, 0xeb3b, 0xebfe, 0xecc1, 0xed83,
- 0xee45, 0xef06, 0xefc8, 0xf088, 0xf149, 0xf209, 0xf2c8, 0xf387,
- 0xf446, 0xf505, 0xf5c3, 0xf680, 0xf73e, 0xf7fb, 0xf8b7, 0xf973,
- 0xfa2f, 0xfaea, 0xfba5, 0xfc60, 0xfd1a, 0xfdd4, 0xfe8e, 0xff47
-};
-
/**
* nau8825_sema_acquire - acquire the semaphore of nau88l25
* @nau8825: component to register the codec private data with
@@ -368,65 +332,14 @@ static void nau8825_hpvol_ramp(struct nau8825 *nau8825,
}

/**
- * nau8825_intlog10_dec3 - Computes log10 of a value
- * the result is round off to 3 decimal. This function takes reference to
- * dvb-math. The source code locates as the following.
- * Linux/drivers/media/dvb-core/dvb_math.c
+ * nau8825_intlog10_dec3 - Computes log10 of a value, rounding the result to 3 decimal places.
* @value: input for log10
*
* return log10(value) * 1000
*/
static u32 nau8825_intlog10_dec3(u32 value)
{
- u32 msb, logentry, significand, interpolation, log10val;
- u64 log2val;
-
- /* first detect the msb (count begins at 0) */
- msb = fls(value) - 1;
- /**
- * now we use a logtable after the following method:
- *
- * log2(2^x * y) * 2^24 = x * 2^24 + log2(y) * 2^24
- * where x = msb and therefore 1 <= y < 2
- * first y is determined by shifting the value left
- * so that msb is bit 31
- * 0x00231f56 -> 0x8C7D5800
- * the result is y * 2^31 -> "significand"
- * then the highest 9 bits are used for a table lookup
- * the highest bit is discarded because it's always set
- * the highest nine bits in our example are 100011000
- * so we would use the entry 0x18
- */
- significand = value << (31 - msb);
- logentry = (significand >> 23) & 0xff;
- /**
- * last step we do is interpolation because of the
- * limitations of the log table the error is that part of
- * the significand which isn't used for lookup then we
- * compute the ratio between the error and the next table entry
- * and interpolate it between the log table entry used and the
- * next one the biggest error possible is 0x7fffff
- * (in our example it's 0x7D5800)
- * needed value for next table entry is 0x800000
- * so the interpolation is
- * (error / 0x800000) * (logtable_next - logtable_current)
- * in the implementation the division is moved to the end for
- * better accuracy there is also an overflow correction if
- * logtable_next is 256
- */
- interpolation = ((significand & 0x7fffff) *
- ((logtable[(logentry + 1) & 0xff] -
- logtable[logentry]) & 0xffff)) >> 15;
-
- log2val = ((msb << 24) + (logtable[logentry] << 8) + interpolation);
- /**
- * log10(x) = log2(x) * log10(2)
- */
- log10val = (log2val * LOG10_MAGIC) >> 31;
- /**
- * the result is round off to 3 decimal
- */
- return log10val / ((1 << 24) / 1000);
+ return intlog10(value) / ((1 << 24) / 1000);
}

/**
--
2.40.0.1.gaa8946217a0b