From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.andi.de1.cc (mail.andi.de1.cc [178.238.236.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 55EEF3D669B; Mon, 10 Aug 2026 12:40:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.238.236.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786365603; cv=none; b=NCqwUB1SkFZ9VRxz4VwvT/hFHiLSExeLdP3DkhidunE3LIgWJD+p0ILPZPz41sA1zMsqbvOJWXbab1pTHrVf5vZvcA4pI73q/xmL3dCHLcg1BPTPjuzbHfVYFHnfVI5nWsjyrXldTkMymsGlDpyHYFzBXW0NJsJ9y/6tuBobBAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786365603; c=relaxed/simple; bh=idY+TMDwbQ5ONQBtcS1ma7Z6izl5WGX4G7umMEjIKZM=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=pZawqWhxXFufGgXYaaXnt4gfnm5dY8J47+AXVsff9yd9cDbJ9/yLR9M7DtkqijbVgNt07AlusjFXOOGUOhTwUn+xmDv97Dm5JzRqFo2LIZa2gV8YOCTDKi/+pzOuoQZT7WlyZ4d7/NQfIIsePPLEwix7mnOdLKZbc2gBWZeFN0Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kemnade.info; spf=pass smtp.mailfrom=kemnade.info; dkim=pass (2048-bit key) header.d=kemnade.info header.i=@kemnade.info header.b=8ARx8TI3; arc=none smtp.client-ip=178.238.236.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kemnade.info Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kemnade.info Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kemnade.info header.i=@kemnade.info header.b="8ARx8TI3" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kemnade.info; s=20220719; h=References:In-Reply-To:Subject:Cc:To:From: Reply-To:Content-ID:Content-Description; bh=RY/1wmCxCIFM0LLRBnTLXmBpxbfVg0FeVcj6W7X9LH0=; t=1786365602; x=1787575202; b=8ARx8TI3PDgp8yyRWt3GU3iy1krWHsiSrXbJLxz137kmerIXl1MTsYcTX+3MEYDQAWVu7BWtxx6 fjKpt1JyJ2o9wsWOdHzz0RVHnTsSCeWOui0hZuCThrlz2ZOjeOrtd5eBM5Y6QlJbwU4qeAxcy25NK MM+Q6pxd0wzaqp43mVR0IEbNtCvw2kD5gSNusU4/5Tn03UzR5EsPuzUdo5D4ZVybKVmqXSwqWtvw5 EgMI1qv1mFxCSflFP6TRTOgUe3DhTzkUdqp9dABBRYEi9KJLBhK/XxsHIe4SkduSStZVPIWoj4d2I izBRT4VKgRrOju3JBGlRwBoxK3eaBpQu+o8g==; Date: Mon, 10 Aug 2026 14:39:14 +0200 From: Andreas Kemnade To: "H. Nikolaus Schaller" Cc: Daniel Thompson , Grond , Stefan Leichter , Grazvydas Ignotas , Tony Lindgren , Ethan Nelson-Moore , Jarkko Nikula , Sascha Hauer , Lee Jones , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Liam Girdwood , Mark Brown , Aaro Koskinen , Kevin Hilman , Roger Quadros , Russell King , Jingoo Han , Helge Deller , Jaroslav Kysela , Takashi Iwai , Sen Wang , Richard Fitzgerald , Arnd Bergmann , Srinivas Kandagatla , Kuninori Morimoto , Charles Keepax , Niranjan H Y , letux-kernel@openphoenux.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, kernel@pyra-handheld.com, mfd@lists.linux.dev Subject: Re: [PATCH 15/16] backlight: remove pandora_bl Message-ID: <20260810143914.64d29a5c@kemnade.info> In-Reply-To: References: X-Mailer: Claws Mail 4.3.1 (GTK 3.24.49; aarch64-unknown-linux-gnu) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 10 Aug 2026 12:45:16 +0200 "H. Nikolaus Schaller" wrote: > Hi Daniel, > > > Am 10.08.2026 um 12:35 schrieb Daniel Thompson : > > > > On Sat, Jul 11, 2026 at 08:02:02AM +0200, H. Nikolaus Schaller wrote: > >> Retire the platform specific pandora backlight driver since > >> it can now be replaced by twl_pm and device tree. > >> > >> Signed-off-by: H. Nikolaus Schaller > > > > Yay! > > > > Reviewed-by: Daniel Thompson (RISCstar) > > Well, there were some good comments by Sahiko to the prerequisites of this patch, > because it has one speciality the PWM BL driver does not handle (avoid > interpretation of PWM signals as W1 protocol). > > I haven't found time to work on this, so we can't remove this yet. > > In the end it may either remain a pandora_bl driver (converted to DT) > or become a patch for something else. > But then it is a TPS61161 on top of PWM, not a pandora driver. And then there might be just a quirk for that chip in the pwm_bl using triggered by a compatible. I guess the quirk is this: if (priv->old_state == PANDORABL_WAS_OFF) { - /* - * set PWM duty cycle to max. TPS61161 seems to use this - * to calibrate it's PWM sensitivity when it starts. - */ - twl_i2c_write_u8(TWL_MODULE_PWM, MAX_VALUE, TWL_PWM0_OFF); - - /* first enable clock, then PWM0 out */ - twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1); - r &= ~PWM0_ENABLE; - r |= PWM0_CLK_ENABLE; - twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1); - r |= PWM0_ENABLE; - twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1); - - /* - * TI made it very easy to enable digital control, so easy that - * it often triggers unintentionally and disabes PWM control, - * so wait until 1 wire mode detection window ends. - */ - usleep_range(2000, 10000); - } Regards, Andreas