Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   "S.j. Wang" <shengjiu.wang@nxp.com>
To:     Charles Keepax <ckeepax@opensource.cirrus.com>
CC:     "lgirdwood@gmail.com" <lgirdwood@gmail.com>,
        "broonie@kernel.org" <broonie@kernel.org>,
        "perex@perex.cz" <perex@perex.cz>,
        "tiwai@suse.com" <tiwai@suse.com>,
        "kuninori.morimoto.gx@renesas.com" <kuninori.morimoto.gx@renesas.com>,
        "patches@opensource.cirrus.com" <patches@opensource.cirrus.com>,
        "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] ASoC: wm8960: Fix clock configuration on slave mode
Thread-Topic: [PATCH] ASoC: wm8960: Fix clock configuration on slave mode
Thread-Index: Ade/8l8YtsfbNm3JQKGBs4KZNAV6Ig==
Date:   Wed, 13 Oct 2021 05:24:22 +0000
Message-ID: <PAXPR04MB847688DF669A1CC5243F761BE3B79@PAXPR04MB8476.eurprd04.prod.outlook.com>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?cydBPt3fExJm0fxMgIvZMN82h+qFQqap8T3bbGWw5SIorFQNS+CtXqWY1K63?=
 =?us-ascii?Q?+Jr2Pm4KEtN4cM465mpwnX80b/4mKeV8Bh5bL5lHDOwEcz70aIevnv+wH76t?=
 =?us-ascii?Q?WXUfz7lv8soboPi96MizFD2A12P1ODtUXfJ4EVNgaf7VpPU5DgzS1frV/w1F?=
 =?us-ascii?Q?6ju+P5wGWkE9QLE503RLjkm5uDHKS9vS8wi2klAiHAzf62CfDQmIeP00PAs9?=
 =?us-ascii?Q?HlowrvT1L2VeOoDRLKvozTSm/nEdr8SVHJaom1kPgw3PQCiszJ+/ynvjQIvW?=
 =?us-ascii?Q?oUGfcY9S/Qum3sAllktYi8sM02DI+8H9loM6F7myMpzlUWp8wr+tK3J0JuFq?=
 =?us-ascii?Q?F67leBYVJARvLbdGYjnqoiS5BhDVh336n157xgnD4WfRpk+M2DPUIV+pIjqd?=
 =?us-ascii?Q?1no9yT+eR5v7D1ktJWk009mOG5HtcScpJG0lIkRsIQhmuzE9cBpHInHH3Drp?=
 =?us-ascii?Q?mvHlGWmlQm8St2WjPa/ipwYiavdzT5Xdnx4N4OjbWCohtT2aYhneNVqEW73n?=
 =?us-ascii?Q?tgLxMznLIppoTMhTSfcaH7Tqn+BqxyYuZUi+4mGC7hqV7jfHp6Jbk0ZmaFrH?=
 =?us-ascii?Q?U9yYDWMnOLF7ekWuCutG7e9P0n2W3IIZC6ryVYtWdTcHZdaG4Q1gzkPL2ha7?=
 =?us-ascii?Q?4l4kEWsD5EkeHSVsvjWrCQ2wfCl27LdxL600Ge+jihsHB1KjgL1hwbvJ/bPB?=
 =?us-ascii?Q?mDYhPKDo7g58wMFsv9UTBL2bwLVg3zbhx+lwjS4WzrEnYzxQfgIqCu3cUoCH?=
 =?us-ascii?Q?/Fc0iWymFCINELCj87tKBa4wO6V9IVhSsKenDb1de7j6u+BmWk9YUCGZGUc2?=
 =?us-ascii?Q?dtYC4//7FmaO3LkFMTNTVhXa27e86HYCCjDwN9HrSoV+6df0bd38r4P2wfxL?=
 =?us-ascii?Q?vWaUvmijA2xAXMBnT1x+YYtJiKQi22w1S93+xp65GkqTspPwP3sQx8w+kaE7?=
 =?us-ascii?Q?1NPcedMrnOedHcs2QS0HVw2tOT3SGGYAHXetSE6eN7lsMAI3gtsKF4ELqOEV?=
 =?us-ascii?Q?uU4QELcuw31/Qoud4moX9VBkuEoM3o1qITru4xmRsDO70pPGa6i+oQBe9FFn?=
 =?us-ascii?Q?XWV5YzjztC1W+aIv2zengY39RY5poHeazMdeNa5g1WGhUifAmPI/eJCvOTpC?=
 =?us-ascii?Q?nepiblNV3zTfG5196xYIca1C44aWA6qaz25PpZ4ajexWSJBn6LTflCJMfHS1?=
 =?us-ascii?Q?sqUiCiatk+ZPCyPlxhy+E9HAXvC1mrdwMr+0T9MHfrQ9ySEgCbIcJ3Aw4ali?=
 =?us-ascii?Q?RKdDX21OrFID/kr2BkqFizNN4IHZEhmuDT3lZGrKjpFqFHVK6BNXq5s/BGU9?=
 =?us-ascii?Q?Wuo=3D?=
x-ms-exchange-transport-forked: True
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: nxp.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: PAXPR04MB8476.eurprd04.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: a9cca2af-57d7-424b-f020-08d98e09b722
X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Oct 2021 05:24:22.7408
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: Rh1YcE0Q1SxMDoXfG6z0ICnSDWKwzZ42olILQbeb1o0gDKKWRE1+BBpiVb+sHbGjIi3Etp+8sQ+nMuvqBFiGKg==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: PAXPR04MB9139
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

> On Tue, Sep 07, 2021 at 05:11:09PM +0800, Shengjiu Wang wrote:
> > There is a noise issue for 8kHz sample rate on slave mode.
> > Compared with master mode, the difference is the DACDIV setting, after
> > correcting the DACDIV, the noise is gone.
> >
> > There is no noise issue for 48kHz sample rate, because the default
> > value of DACDIV is correct for 48kHz.
> >
> > So wm8960_configure_clocking() should be functional for ADC and DAC
> > function even if it is slave mode.
> >
> > In order to be compatible for old use case, just add condition for
> > checking that sysclk is zero with slave mode.
> >
> > Fixes: 0e50b51aa22f ("ASoC: wm8960: Let wm8960 driver configure its
> > bit clock and frame clock")
> > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> > ---
> >  sound/soc/codecs/wm8960.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c
> > index 9e621a254392..9c6af76a60fd 100644
> > --- a/sound/soc/codecs/wm8960.c
> > +++ b/sound/soc/codecs/wm8960.c
> > @@ -742,7 +742,7 @@ static int wm8960_configure_clocking(struct
> snd_soc_component *component)
> >       int i, j, k;
> >       int ret;
> >
> > -     if (!(iface1 & (1<<6))) {
> > +     if (!(iface1 & (1 << 6)) && !wm8960->sysclk) {
> >               dev_dbg(component->dev,
> >                       "Codec is slave mode, no need to configure
> > clock\n");
>=20
> Looking through the datasheet it just looks like this if statement has al=
ways
> been non-sense, it looks pretty clear the clocking should still be config=
ured in
> slave mode (apart from BCLKDIV which is presumably ignored in slave mode)=
.
>=20
> I would be slightly inclined to suggest it would be better to just fixup =
any
> systems not setting sysclk for slave mode, but I am assuming you are talk=
ing
> primarily about out of tree systems. So I think we need to at least updat=
e the
> message here as well, it should probably change to a warning and state th=
at
> the we are proceeding with no clock configuration, rather than erroneousl=
y
> saying it doesn't need one.
>=20
> Thanks,
> Charles

Sorry for missing your email. I will update it in v2.
Thanks.

Best regards
Wang Shengjiu