Re: [PATCH] ASoC: cs42l42: Regmap must use_single_read/write

From: Charles Keepax <ckeepax@opensource.cirrus.com>
To: Richard Fitzgerald <rf@opensource.cirrus.com>
Cc: <broonie@kernel.org>, <alsa-devel@alsa-project.org>,
	<patches@opensource.cirrus.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] ASoC: cs42l42: Regmap must use_single_read/write
Date: Tue, 11 May 2021 14:56:43 +0000	[thread overview]
Message-ID: <20210511145643.GE64205@ediswmail.ad.cirrus.com> (raw)
In-Reply-To: <20210511132855.27159-1-rf@opensource.cirrus.com>

On Tue, May 11, 2021 at 02:28:55PM +0100, Richard Fitzgerald wrote:
> cs42l42 does not support standard burst transfers so the use_single_read
> and use_single_write flags must be set in the regmap config.
> 
> Because of this bug, the patch:
> 
> commit 0a0eb567e1d4 ("ASoC: cs42l42: Minor error paths fixups")
> 
> broke cs42l42 probe() because without the use_single_* flags it causes
> regmap to issue a burst read.
> 
> However, the missing use_single_* could cause problems anyway because the
> regmap cache can attempt burst transfers if these flags are not set.
> 
> Fixes: 2c394ca79604 ("ASoC: Add support for CS42L42 codec")
> Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
> ---

Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>

Thanks Richard, I guess I better check the other devices I fixed
up for the same issue, as I am guessing that could probably
affect a few more. The few I have hardware to test already have
the single stuff set.

Thanks,
Charles