From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fabio Estevam Subject: Re: [PATCH] sound: soc: fsl: Do not set DAI sysclk when it is equal to system freq Date: Sun, 3 Sep 2017 12:44:17 +0000 Message-ID: References: <1504436701-20700-1-git-send-email-lukma@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from EUR01-DB5-obe.outbound.protection.outlook.com (mail-db5eur01on0065.outbound.protection.outlook.com [104.47.2.65]) by alsa0.perex.cz (Postfix) with ESMTP id C35B1266DCC for ; Sun, 3 Sep 2017 14:44:18 +0200 (CEST) In-Reply-To: <1504436701-20700-1-git-send-email-lukma@denx.de> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Lukasz Majewski , Timur Tabi , Nicolin Chen , Xiubo Li , Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , "festevam@gmail.com" Cc: "alsa-devel@alsa-project.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" List-Id: alsa-devel@alsa-project.org [Sorry for the top-posting] The driver currently has: /* * Hardware limitation: The bclk rate must be * never greater than 1/5 IPG clock rate */ if (freq * 5 > clk_get_rate(ssi_private->clk)) { dev_err(cpu_dai->dev, "bitclk > ipgclk/5\n"); return -EINVAL; } Isn't this properly taking care of the clock restriction? ________________________________ From: Lukasz Majewski Sent: Sunday, September 3, 2017 8:05:01 AM To: Timur Tabi; Nicolin Chen; Xiubo Li; Fabio Estevam; Liam Girdwood; Mark Brown; Jaroslav Kysela; Takashi Iwai Cc: alsa-devel@alsa-project.org; linuxppc-dev@lists.ozlabs.org; linux-kernel@vger.kernel.org; Lukasz Majewski Subject: [PATCH] sound: soc: fsl: Do not set DAI sysclk when it is equal to system freq The problem is visible in the following setup (on the imx6q): "simple-audio-card" -> ssi2 -> I2S + I2C -> codec The function call log (simple-card probe -> CONFIG_SND_SIMPLE_CARD): asoc_simple_card_init_dai() @ sound/soc/generic/simple-card-utils.c snd_soc_dai_set_sysclk() fsl_ssi_set_dai_sysclk() @ sound/soc/fsl/fsl_ssi.c The last call is changing the bit clock (BCLK) frequency to SSI's IP block clock (ipg = 66 MHz) [1]. This is wrong, since IMX SSI block requires the I2S BCLK to be less than 1/5 of [1]. As a result the driver initialization passes without any errors, but the speaker-test test case breaks. This commit checks if the fsl_ssi_set_dai_sysclk() frequency passed is not equal to [1]. Signed-off-by: Lukasz Majewski --- sound/soc/fsl/fsl_ssi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c index 173cb84..1186fa9 100644 --- a/sound/soc/fsl/fsl_ssi.c +++ b/sound/soc/fsl/fsl_ssi.c @@ -809,6 +809,8 @@ static int fsl_ssi_set_dai_sysclk(struct snd_soc_dai *cpu_dai, int clk_id, unsigned int freq, int dir) { struct fsl_ssi_private *ssi_private = snd_soc_dai_get_drvdata(cpu_dai); + if (clk_get_rate(ssi_private->clk) == freq) + return 0; ssi_private->bitclk_freq = freq; -- 2.1.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from EUR01-DB5-obe.outbound.protection.outlook.com (mail-db5eur01on0053.outbound.protection.outlook.com [104.47.2.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xlXjg1jmyzDqjK for ; Sun, 3 Sep 2017 22:44:22 +1000 (AEST) From: Fabio Estevam To: Lukasz Majewski , Timur Tabi , Nicolin Chen , Xiubo Li , Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , "festevam@gmail.com" CC: "alsa-devel@alsa-project.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] sound: soc: fsl: Do not set DAI sysclk when it is equal to system freq Date: Sun, 3 Sep 2017 12:44:17 +0000 Message-ID: References: <1504436701-20700-1-git-send-email-lukma@denx.de> In-Reply-To: <1504436701-20700-1-git-send-email-lukma@denx.de> Content-Type: multipart/alternative; boundary="_000_AM5PR0401MB262706674539BFE651706CC6E3900AM5PR0401MB2627_" MIME-Version: 1.0 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --_000_AM5PR0401MB262706674539BFE651706CC6E3900AM5PR0401MB2627_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable [Sorry for the top-posting] The driver currently has: /* * Hardware limitation: The bclk rate must be * never greater than 1/5 IPG clock rate */ if (freq * 5 > clk_get_rate(ssi_private->clk)) { dev_err(cpu_dai->dev, "bitclk > ipgclk/5\n"); return -EINVAL; } Isn't this properly taking care of the clock restriction? ________________________________ From: Lukasz Majewski Sent: Sunday, September 3, 2017 8:05:01 AM To: Timur Tabi; Nicolin Chen; Xiubo Li; Fabio Estevam; Liam Girdwood; Mark = Brown; Jaroslav Kysela; Takashi Iwai Cc: alsa-devel@alsa-project.org; linuxppc-dev@lists.ozlabs.org; linux-kerne= l@vger.kernel.org; Lukasz Majewski Subject: [PATCH] sound: soc: fsl: Do not set DAI sysclk when it is equal to= system freq The problem is visible in the following setup (on the imx6q): "simple-audio-card" -> ssi2 -> I2S + I2C -> codec The function call log (simple-card probe -> CONFIG_SND_SIMPLE_CARD): asoc_simple_card_init_dai() @ sound/soc/generic/simple-card-utils.c snd_soc_dai_set_sysclk() fsl_ssi_set_dai_sysclk() @ sound/soc/fsl/fsl_ssi.c The last call is changing the bit clock (BCLK) frequency to SSI's IP block clock (ipg =3D 66 MHz) [1]. This is wrong, since IMX SSI block requires the I2S BCLK to be less than 1/5 of [1]. As a result the driver initialization passes without any errors, but the speaker-test test case breaks. This commit checks if the fsl_ssi_set_dai_sysclk() frequency passed is not equal to [1]. Signed-off-by: Lukasz Majewski --- sound/soc/fsl/fsl_ssi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c index 173cb84..1186fa9 100644 --- a/sound/soc/fsl/fsl_ssi.c +++ b/sound/soc/fsl/fsl_ssi.c @@ -809,6 +809,8 @@ static int fsl_ssi_set_dai_sysclk(struct snd_soc_dai *c= pu_dai, int clk_id, unsigned int freq, int dir) { struct fsl_ssi_private *ssi_private =3D snd_soc_dai_get_drvdata(cp= u_dai); + if (clk_get_rate(ssi_private->clk) =3D=3D freq) + return 0; ssi_private->bitclk_freq =3D freq; -- 2.1.4 --_000_AM5PR0401MB262706674539BFE651706CC6E3900AM5PR0401MB2627_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

[Sorry for the top-posting]


The driver currently has:


/*
* Hardware limitation: The bclk= rate must be
* never greater than 1/5 IPG cl= ock rate
*/
if (freq * 5 > clk_get_rate(= ssi_private->clk)) {
dev_err(cpu_dai->dev, "= bitclk > ipgclk/5\n");
return -EINVAL;
}

Isn't this properly taking care of the clock restriction?

From: Lukasz Majewski <= ;lukma@denx.de>
Sent: Sunday, September 3, 2017 8:05:01 AM
To: Timur Tabi; Nicolin Chen; Xiubo Li; Fabio Estevam; Liam Girdwood= ; Mark Brown; Jaroslav Kysela; Takashi Iwai
Cc: alsa-devel@alsa-project.org; linuxppc-dev@lists.ozlabs.org; linu= x-kernel@vger.kernel.org; Lukasz Majewski
Subject: [PATCH] sound: soc: fsl: Do not set DAI sysclk when it is e= qual to system freq
 
The problem is visible in the following setup (on = the imx6q):
"simple-audio-card" -> ssi2 -> I2S + I2C -> codec
The function call log (simple-card probe -> CONFIG_SND_SIMPLE_CARD):

asoc_simple_card_init_dai() @ sound/soc/generic/simple-card-utils.c
snd_soc_dai_set_sysclk()
fsl_ssi_set_dai_sysclk() @ sound/soc/fsl/fsl_ssi.c

The last call is changing the bit clock (BCLK) frequency to SSI's IP
block clock (ipg =3D 66 MHz) [1].
This is wrong, since IMX SSI block requires the I2S BCLK to be less
than 1/5 of [1].

As a result the driver initialization passes without any errors, but the speaker-test test case breaks.

This commit checks if the fsl_ssi_set_dai_sysclk() frequency passed is
not equal to [1].

Signed-off-by: Lukasz Majewski <lukma@denx.de>
---
 sound/soc/fsl/fsl_ssi.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index 173cb84..1186fa9 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -809,6 +809,8 @@ static int fsl_ssi_set_dai_sysclk(struct snd_soc_da= i *cpu_dai,
            &nb= sp;    int clk_id, unsigned int freq, int dir)
 {
         struct fsl_ssi_private *ss= i_private =3D snd_soc_dai_get_drvdata(cpu_dai);
+       if (clk_get_rate(ssi_private->= clk) =3D=3D freq)
+           &nbs= p;   return 0;
 
         ssi_private->bitclk_fre= q =3D freq;
 
--
2.1.4

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