[alsa-devel] [PATCH] ALSA: 6fire: use the kernel's built-in bit reverse table

Daniel Mack zonque at gmail.com
Sat Apr 23 20:56:43 CEST 2011

Signed-off-by: Daniel Mack <zonque at gmail.com>
Cc: Torsten Schenk <torsten.schenk at zoho.com>
Cc: Takashi Iwai <tiwai at suse.de>
 sound/usb/6fire/firmware.c |   29 ++---------------------------
 sound/usb/Kconfig          |    1 +
 2 files changed, 3 insertions(+), 27 deletions(-)

diff --git a/sound/usb/6fire/firmware.c b/sound/usb/6fire/firmware.c
index f075cdf..d47beff 100644
--- a/sound/usb/6fire/firmware.c
+++ b/sound/usb/6fire/firmware.c
@@ -15,6 +15,7 @@
 #include <linux/firmware.h>
+#include <linux/bitrev.h>
 #include "firmware.h"
 #include "chip.h"
@@ -27,32 +28,6 @@ enum {
-static const u8 BIT_REVERSE_TABLE[256] = {
-	0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 0x10, 0x90, 0x50,
-	0xd0, 0x30, 0xb0, 0x70, 0xf0, 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8,
-	0x68, 0xe8, 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, 0x04,
-	0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, 0x14, 0x94, 0x54, 0xd4,
-	0x34, 0xb4, 0x74, 0xf4, 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c,
-	0xec, 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, 0x02, 0x82,
-	0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, 0x12, 0x92, 0x52, 0xd2, 0x32,
-	0xb2, 0x72, 0xf2, 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
-	0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, 0x06, 0x86, 0x46,
-	0xc6, 0x26, 0xa6, 0x66, 0xe6, 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6,
-	0x76, 0xf6, 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, 0x1e,
-	0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, 0x01, 0x81, 0x41, 0xc1,
-	0x21, 0xa1, 0x61, 0xe1, 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71,
-	0xf1, 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 0x19, 0x99,
-	0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, 0x05, 0x85, 0x45, 0xc5, 0x25,
-	0xa5, 0x65, 0xe5, 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
-	0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, 0x1d, 0x9d, 0x5d,
-	0xdd, 0x3d, 0xbd, 0x7d, 0xfd, 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3,
-	0x63, 0xe3, 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, 0x0b,
-	0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, 0x1b, 0x9b, 0x5b, 0xdb,
-	0x3b, 0xbb, 0x7b, 0xfb, 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67,
-	0xe7, 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, 0x0f, 0x8f,
-	0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 0x1f, 0x9f, 0x5f, 0xdf, 0x3f,
-	0xbf, 0x7f, 0xff };
  * wMaxPacketSize of pcm endpoints.
  * keep synced with rates_in_packet_size and rates_out_packet_size in pcm.c
@@ -338,7 +313,7 @@ static int usb6fire_fw_fpga_upload(
 	while (c != end) {
 		for (i = 0; c != end && i < FPGA_BUFSIZE; i++, c++)
-			buffer[i] = BIT_REVERSE_TABLE[(u8) *c];
+			buffer[i] = byte_rev_table[(u8) *c];
 		ret = usb6fire_fw_fpga_write(device, buffer, i);
 		if (ret < 0) {
diff --git a/sound/usb/Kconfig b/sound/usb/Kconfig
index cc47a9c..8beb775 100644
--- a/sound/usb/Kconfig
+++ b/sound/usb/Kconfig
@@ -101,6 +101,7 @@ config SND_USB_US122L
 config SND_USB_6FIRE
         tristate "TerraTec DMX 6Fire USB"
         select FW_LOADER
+        select BITREVERSE
         select SND_RAWMIDI
         select SND_PCM

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