ALSA: Clean up 64bit division functions

Replace the house-made div64_32() with the standard div_u64*() functions.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/pcm.h

@@ -486,80 +486,6 @@ void snd_pcm_detach_substream(struct snd_pcm_substream *substream);
 void snd_pcm_vma_notify_data(void *client, void *data);
 int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file, struct vm_area_struct *area);
 
-#if BITS_PER_LONG >= 64
-
-static inline void div64_32(u_int64_t *n, u_int32_t div, u_int32_t *rem)
-{
-	*rem = *n % div;
-	*n /= div;
-}
-
-#elif defined(i386)
-
-static inline void div64_32(u_int64_t *n, u_int32_t div, u_int32_t *rem)
-{
-	u_int32_t low, high;
-	low = *n & 0xffffffff;
-	high = *n >> 32;
-	if (high) {
-		u_int32_t high1 = high % div;
-		high /= div;
-		asm("divl %2":"=a" (low), "=d" (*rem):"rm" (div), "a" (low), "d" (high1));
-		*n = (u_int64_t)high << 32 | low;
-	} else {
-		*n = low / div;
-		*rem = low % div;
-	}
-}
-#else
-
-static inline void divl(u_int32_t high, u_int32_t low,
-			u_int32_t div,
-			u_int32_t *q, u_int32_t *r)
-{
-	u_int64_t n = (u_int64_t)high << 32 | low;
-	u_int64_t d = (u_int64_t)div << 31;
-	u_int32_t q1 = 0;
-	int c = 32;
-	while (n > 0xffffffffU) {
-		q1 <<= 1;
-		if (n >= d) {
-			n -= d;
-			q1 |= 1;
-		}
-		d >>= 1;
-		c--;
-	}
-	q1 <<= c;
-	if (n) {
-		low = n;
-		*q = q1 | (low / div);
-		*r = low % div;
-	} else {
-		*r = 0;
-		*q = q1;
-	}
-	return;
-}
-
-static inline void div64_32(u_int64_t *n, u_int32_t div, u_int32_t *rem)
-{
-	u_int32_t low, high;
-	low = *n & 0xffffffff;
-	high = *n >> 32;
-	if (high) {
-		u_int32_t high1 = high % div;
-		u_int32_t low1 = low;
-		high /= div;
-		divl(high1, low1, div, &low, rem);
-		*n = (u_int64_t)high << 32 | low;
-	} else {
-		*n = low / div;
-		*rem = low % div;
-	}
-}
-#endif
-
 /*
  *  PCM library
  */

sound/core/oss/pcm_oss.c

@@ -31,6 +31,7 @@
 #include <linux/time.h>
 #include <linux/vmalloc.h>
 #include <linux/moduleparam.h>
+#include <linux/math64.h>
 #include <linux/string.h>
 #include <sound/core.h>
 #include <sound/minors.h>
@@ -617,9 +618,7 @@ static long snd_pcm_oss_bytes(struct snd_pcm_substream *substream, long frames)
 #else
 	{
 		u64 bsize = (u64)runtime->oss.buffer_bytes * (u64)bytes;
-		u32 rem;
-		div64_32(&bsize, buffer_size, &rem);
-		return (long)bsize;
+		return div_u64(bsize, buffer_size);
 	}
 #endif
 }

sound/core/pcm_lib.c

@@ -22,6 +22,7 @@
 
 #include <linux/slab.h>
 #include <linux/time.h>
+#include <linux/math64.h>
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/info.h>
@@ -452,7 +453,7 @@ static inline unsigned int muldiv32(unsigned int a, unsigned int b,
 		*r = 0;
 		return UINT_MAX;
 	}
-	div64_32(&n, c, r);
+	n = div_u64_rem(n, c, r);
 	if (n >= UINT_MAX) {
 		*r = 0;
 		return UINT_MAX;

sound/pci/rme9652/hdsp.c

@@ -28,6 +28,7 @@
 #include <linux/pci.h>
 #include <linux/firmware.h>
 #include <linux/moduleparam.h>
+#include <linux/math64.h>
 
 #include <sound/core.h>
 #include <sound/control.h>
@@ -1047,15 +1048,14 @@ static int hdsp_set_interrupt_interval(struct hdsp *s, unsigned int frames)
 static void hdsp_set_dds_value(struct hdsp *hdsp, int rate)
 {
 	u64 n;
-	u32 r;
 
 	if (rate >= 112000)
 		rate /= 4;
 	else if (rate >= 56000)
 		rate /= 2;
 
 	n = DDS_NUMERATOR;
-	div64_32(&n, rate, &r);
+	n = div_u64(n, rate);
 	/* n should be less than 2^32 for being written to FREQ register */
 	snd_BUG_ON(n >> 32);
 	/* HDSP_freqReg and HDSP_resetPointer are the same, so keep the DDS
@@ -3097,7 +3097,6 @@ static int snd_hdsp_get_adat_sync_check(struct snd_kcontrol *kcontrol, struct sn
 static int hdsp_dds_offset(struct hdsp *hdsp)
 {
 	u64 n;
-	u32 r;
 	unsigned int dds_value = hdsp->dds_value;
 	int system_sample_rate = hdsp->system_sample_rate;
 
@@ -3109,7 +3108,7 @@ static int hdsp_dds_offset(struct hdsp *hdsp)
 	 * dds_value = n / rate
 	 * rate = n / dds_value
 	 */
-	div64_32(&n, dds_value, &r);
+	n = div_u64(n, dds_value);
 	if (system_sample_rate >= 112000)
 		n *= 4;
 	else if (system_sample_rate >= 56000)

sound/pci/rme9652/hdspm.c

@@ -29,6 +29,7 @@
 #include <linux/moduleparam.h>
 #include <linux/slab.h>
 #include <linux/pci.h>
+#include <linux/math64.h>
 #include <asm/io.h>
 
 #include <sound/core.h>
@@ -831,7 +832,6 @@ static int hdspm_set_interrupt_interval(struct hdspm * s, unsigned int frames)
 static void hdspm_set_dds_value(struct hdspm *hdspm, int rate)
 {
 	u64 n;
-	u32 r;
 
 	if (rate >= 112000)
 		rate /= 4;
@@ -844,7 +844,7 @@ static void hdspm_set_dds_value(struct hdspm *hdspm, int rate)
         */	   
 	/* n = 104857600000000ULL; */ /*  =  2^20 * 10^8 */
 	n = 110100480000000ULL;    /* Value checked for AES32 and MADI */
-	div64_32(&n, rate, &r);
+	n = div_u64(n, rate);
 	/* n should be less than 2^32 for being written to FREQ register */
 	snd_BUG_ON(n >> 32);
 	hdspm_write(hdspm, HDSPM_freqReg, (u32)n);