Commit 689c6912 authored by Andreas Mohr's avatar Andreas Mohr Committed by Takashi Iwai
Browse files

ALSA: azt3328: improve snd_azf3328_codec_setdmaa() 



- add some WARN_ONCE
- add multi-I/O helper (and use helper struct)
- fix off-by-1 DMA length bug
- better variable naming

Signed-off-by: default avatarAndreas Mohr <andi@lisas.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent da237f35

sound/pci/azt3328.c

+51 −15
Original line number Diff line number Diff line
@@ -175,6 +175,7 @@ 


#include <asm/io.h>

#include <linux/init.h>

#include <linux/bug.h> /* WARN_ONCE */

#include <linux/pci.h>

#include <linux/delay.h>

#include <linux/slab.h>
@@ -421,6 +422,21 @@ snd_azf3328_codec_outl(const struct snd_azf3328_codec_data *codec, 
	outl(value, codec->io_base + reg);

}



static inline void

snd_azf3328_codec_outl_multi(const struct snd_azf3328_codec_data *codec,

			     unsigned reg, const void *buffer, int count

)

{

	unsigned long addr = codec->io_base + reg;

	if (count) {

		const u32 *buf = buffer;

		do {

			outl(*buf++, addr);

			addr += 4;

		} while (--count);

	}

}



static inline u32

snd_azf3328_codec_inl(const struct snd_azf3328_codec_data *codec, unsigned reg)

{
@@ -1124,34 +1140,54 @@ snd_azf3328_ctrl_codec_activity(struct snd_azf3328 *chip, 
static void

snd_azf3328_codec_setdmaa(struct snd_azf3328_codec_data *codec,

				unsigned long addr,

				unsigned int count,

				unsigned int size

				unsigned int period_bytes,

				unsigned int buffer_bytes

)

{

	snd_azf3328_dbgcallenter();

	WARN_ONCE(period_bytes & 1, "odd period length!?\n");

	WARN_ONCE(buffer_bytes != 2 * period_bytes,

		 "missed our input expectations! %u vs. %u\n",

		 buffer_bytes, period_bytes);

	if (!codec->running) {

		/* AZF3328 uses a two buffer pointer DMA transfer approach */



		unsigned long flags, addr_area2;

		unsigned long flags;



		/* width 32bit (prevent overflow): */

		u32 count_areas, lengths;

		u32 area_length;

		struct codec_setup_io {

			u32 dma_start_1;

			u32 dma_start_2;

			u32 dma_lengths;

		} __attribute__((packed)) setup_io;



		count_areas = size/2;

		addr_area2 = addr+count_areas;

		snd_azf3328_dbgcodec("setdma: buffers %08lx[%u] / %08lx[%u]\n",

				addr, count_areas, addr_area2, count_areas);

		area_length = buffer_bytes/2;



		count_areas--; /* max. index */

		setup_io.dma_start_1 = addr;

		setup_io.dma_start_2 = addr+area_length;



		snd_azf3328_dbgcodec(

			"setdma: buffers %08x[%u] / %08x[%u], %u, %u\n",

				setup_io.dma_start_1, area_length,

				setup_io.dma_start_2, area_length,

				period_bytes, buffer_bytes);



		/* Hmm, are we really supposed to decrement this by 1??

		   Most definitely certainly not: configuring full length does

		   work properly (i.e. likely better), and BTW we

		   violated possibly differing frame sizes with this...



		area_length--; |* max. index *|

		*/



		/* build combined I/O buffer length word */

		lengths = (count_areas << 16) | (count_areas);

		setup_io.dma_lengths = (area_length << 16) | (area_length);



		spin_lock_irqsave(codec->lock, flags);

		snd_azf3328_codec_outl(codec, IDX_IO_CODEC_DMA_START_1, addr);

		snd_azf3328_codec_outl(codec, IDX_IO_CODEC_DMA_START_2,

								addr_area2);

		snd_azf3328_codec_outl(codec, IDX_IO_CODEC_DMA_LENGTHS,

								lengths);

		snd_azf3328_codec_outl_multi(

			codec, IDX_IO_CODEC_DMA_START_1, &setup_io, 3

		);

		spin_unlock_irqrestore(codec->lock, flags);

	}

	snd_azf3328_dbgcallleave();