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Date: Fri, 29 Dec 2023 13:45:43 +0100
Message-ID: <87y1ddxjm0.wl-tiwai@suse.de>
From: Takashi Iwai <tiwai@suse.de>
To: Gergo Koteles <soyer@irl.hu>
Cc: Shenghao Ding <shenghao-ding@ti.com>,
	Kevin Lu <kevin-lu@ti.com>,
	Baojun Xu <baojun.xu@ti.com>,
	Jaroslav Kysela <perex@perex.cz>,
	Takashi Iwai <tiwai@suse.com>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	linux-sound@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	alsa-devel@alsa-project.org,
	stable@vger.kernel.org
Subject: Re: [PATCH] ALSA: hda/tas2781: do not use regcache
In-Reply-To: <491aeed0e2eecc3b704ec856f815db21bad3ba0e.1703202126.git.soyer@irl.hu>
References: <491aeed0e2eecc3b704ec856f815db21bad3ba0e.1703202126.git.soyer@irl.hu>
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On Fri, 22 Dec 2023 00:48:56 +0100,
Gergo Koteles wrote:
> 
> There are two problems with using regcache in this module.
> 
> The amplifier has 3 addressing levels (BOOK, PAGE, REG). The firmware
> contains blocks that must be written to BOOK 0x8C. The regcache doesn't
> know anything about BOOK, so regcache_sync writes invalid values to the
> actual BOOK.
> 
> The module handles 2 or more separate amplifiers. The amplifiers have
> different register values, and the module uses only one regmap/regcache
> for all the amplifiers. The regcache_sync only writes the last amplifier
> used.
> 
> The module successfully restores all the written register values (RC
> profile, program, configuration, calibration) without regcache.
> 
> Remove regcache functions and set regmap cache_type to REGCACHE_NONE.
> 
> Link: https://lore.kernel.org/r/21a183b5a08cb23b193af78d4b1114cc59419272.1701906455.git.soyer@irl.hu/
> 
> Fixes: 5be27f1e3ec9 ("ALSA: hda/tas2781: Add tas2781 HDA driver")
> CC: stable@vger.kernel.org
> Signed-off-by: Gergo Koteles <soyer@irl.hu>

Applied to for-linus branch now.  Thanks.


Takashi