From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clemens Ladisch Subject: [PATCH] [13/29] ALSA: dice: optimize reading of consecutive registers Date: Mon, 21 Oct 2013 21:27:59 +0200 Message-ID: <5265803F.9000105@ladisch.de> References: <52657E3B.7040205@ladisch.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <52657E3B.7040205@ladisch.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux1394-devel-bounces@lists.sourceforge.net To: Takashi Iwai Cc: alsa-devel@alsa-project.org, linux1394-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org Instead of reading two consecutive register with two quadlet requests, use one block read request. Signed-off-by: Clemens Ladisch --- sound/firewire/dice.c | 27 +++++++++++---------------- 1 file changed, 11 insertions(+), 16 deletions(-) diff --git a/sound/firewire/dice.c b/sound/firewire/dice.c index 8804e42..e1d8dff 100644 --- a/sound/firewire/dice.c +++ b/sound/firewire/dice.c @@ -374,8 +374,8 @@ static int dice_open(struct snd_pcm_substream *substream) }; struct dice *dice = substream->private_data; struct snd_pcm_runtime *runtime = substream->runtime; - __be32 clock_sel, number_audio, number_midi; - unsigned int rate_index, rate; + __be32 clock_sel, data[2]; + unsigned int rate_index, number_audio, number_midi; int err; err = dice_try_lock(dice); @@ -393,30 +393,25 @@ static int dice_open(struct snd_pcm_substream *substream) err = -ENXIO; goto err_lock; } - rate = dice_rates[rate_index]; - err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST, + err = snd_fw_transaction(dice->unit, TCODE_READ_BLOCK_REQUEST, rx_address(dice, RX_NUMBER_AUDIO), - &number_audio, 4); - if (err < 0) - goto err_lock; - err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST, - rx_address(dice, RX_NUMBER_MIDI), - &number_midi, 4); + data, 2 * 4); if (err < 0) goto err_lock; + number_audio = be32_to_cpu(data[0]); + number_midi = be32_to_cpu(data[1]); runtime->hw = hardware; - runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate); + runtime->hw.rates = snd_pcm_rate_to_rate_bit(dice_rates[rate_index]); snd_pcm_limit_hw_rates(runtime); - runtime->hw.channels_min = be32_to_cpu(number_audio); - runtime->hw.channels_max = be32_to_cpu(number_audio); + runtime->hw.channels_min = number_audio; + runtime->hw.channels_max = number_audio; - amdtp_out_stream_set_parameters(&dice->stream, rate, - be32_to_cpu(number_audio), - be32_to_cpu(number_midi)); + amdtp_out_stream_set_parameters(&dice->stream, dice_rates[rate_index], + number_audio, number_midi); err = snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60135991&iu=/4140/ostg.clktrk