From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr2-f34.google.com (mail-wr2-f34.google.com [74.125.225.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D2F71345EB5 for ; Wed, 30 Sep 2026 09:54:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.225.98 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790762049; cv=none; b=guHHHBjk9VFrOPQT2Q+vt3jvrDzeTAItaKpnRELqM51KZdP+XdIsKUoBwZLwTmT8UH/d3C1ustd5/vV12F/64kqtlJLWCpAR/DrSYrVaMCkmuhM2dARTk14+X4gFujcvkHSLqJo7WoikLQioVWk13GZe/PwPmv7JLFqRyIUTX+s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790762049; c=relaxed/simple; bh=oYL9oH1pXlCS+NfSHpgzBfzfeCrlFDoWfdxKdfswLFo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=laOVwFB0ATuEfboMYORB8XzsZoBbbCxVLPQRwEuXFpjKPS8WPbxwhzkiEPKCOSUDcigDqpyAswhsYvo1pGVwa7vRdi9sA48n7JT7LqyEd162e2T6DiFuNemDqD3t0iB5SjEGX2WB6OEGk5+Dp5Qg/wOnTyM29+ViHTYZBQkvje0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com; spf=pass smtp.mailfrom=baylibre.com; dkim=pass (2048-bit key) header.d=baylibre.com header.i=@baylibre.com header.b=CMYysObh; arc=none smtp.client-ip=74.125.225.98 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=baylibre.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=baylibre.com header.i=@baylibre.com header.b="CMYysObh" Received: by mail-wr2-f34.google.com with SMTP id ffacd0b85a97d-48b01c41135so273165f8f.0 for ; Wed, 30 Sep 2026 02:54:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre.com; s=google; t=1790762046; x=1791366846; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=oYL9oH1pXlCS+NfSHpgzBfzfeCrlFDoWfdxKdfswLFo=; b=CMYysObhr0Od4BQyTTPNfziEcNig+pSClHT294L5OwshEmvvD4+9TbgsAtCR+G7nd0 U8lH0g2vkdps9omWFpKLUGlQnJM/CXsyYLgXn8nJUNoYory0Gy0vrl7C1idvPMHbp9+W MLmujlIUi8TtuNr30KU1cxdBXEHwuBHqfrJYRFNBoBjszo3i5NYygng3REDsZwuoIr9z HfmK8dV+3mFkkm5W/5gHW2gkVcVDWvKYcA20c8DnAAZHKNYRO75KkxQBqBdHBCEZiXrG n4+LGVh122OhXVcE5CSU6m0hV3sZc+CeGJKvrisQ7TRF5nRK5DMqCEzHJlh9Piinks+I C0OQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790762046; x=1791366846; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=oYL9oH1pXlCS+NfSHpgzBfzfeCrlFDoWfdxKdfswLFo=; b=Gk5d6igJJeYU1FR2/TxsC2kiXABYA1FeWw/ygOTV/Y7Sway5R1Ti9CY0MrmvL5odQn mhGwC5G6AIV1Q6l66xA5u3ipRFYIPgpJ58UToYb/qJzvzZQXtdDNrCLn+eIp2Ewn1uzX hwG0LYaQhonwiGcZwrpigAiQWMe31lKJ8rCdhhCG1/uEzxYTnQ4dsxkCF/bTY4kRKYLq u4JnHgDzWig2jiwvjx84TP9UzuDnUmAZHmSQ9ymiYviBaXB6hM+DrELfDA71g6uzlYaa Qn19JR8SVMZAyoy40346GB9UlO+4jQSk46PH+PWQ6hNZwNSJGUJaQRDP5mJhVbYmtAKO PYfQ== X-Forwarded-Encrypted: i=1; AKwUvBxjPGcJbJD6VytGF8z7RXlIL6C8S5k6g+v/n/tBJKr3PEidejGDx66Z80uEjprpwdBtXOxPioBYzAcE0y4=@vger.kernel.org X-Gm-Message-State: AFq9FYLLUQaJrEYEYMRrGJM0q82NsBt5uhRtn0ndKl9KIMS1fLo7n3WQ srbgas7OB2KmEYMRvbNdRkgkpJW2xI6NEQxMiCIdd++aMoUztHqXiB9n9A06tr3Ftab6tXD9sX0 A39t4 X-Gm-Gg: AYBFou13xOF2CrRtdu6+45M/6g65AB/aprl+6kQ7j6T7OjL7q+5U6Hxc5aNFg8fNvpB rNBR1PMN6YgudqhaN89uaSq6CpdRMfTr52f7io2MpAtQ3D+bny2gb2QDOFLkMb4XsW0XMml7ofq rKDEg1+q8N0M6XyOWt6IN6Tqz5zlPDDkBOBTjWknrUCY4SQrrjZrALAUag9b0eMpNK7O1lkW/hx c1+jZyVLebSD2kfpAQXBhhKJH+7iBKR4YBX02O15Deu/A4qm+M9QPuwcfJLk7K+G0U9iX2cTTDI FlrPYQ2OsNTw9R1vsYku9pq8AUvDnDra3Rqu/yrlIWQXBGosR3yMXhQe9aIDVdRehoFRJjsJ5lz nO8b45hdXPiKYHqUUF4Abjn7f4F6WvKB8c06gxM5+Yx1JCGG5s0ZxURDMRvBi4btZtmyhkyn0qf vDnTdKmm59xxKMvB6pxmCO1GY2ZgxTkOPXJiRGm64nkbcnkyovVo8l3K31UYiMjHeaN+NbzncgM Or02A24O9koNfvA6mgtSP6k/k5C3r+fggY13JquWlvSoF4dSLUJgEuTvKq8Ig== X-Received: by 2002:a05:6000:2289:b0:48a:fcec:2a1b with SMTP id ffacd0b85a97d-48b024de5ccmr1835899f8f.17.1790762045816; Wed, 30 Sep 2026 02:54:05 -0700 (PDT) Received: from localhost (p200300f65f19a904ced9d7b419fb4926.dip0.t-ipconnect.de. [2003:f6:5f19:a904:ced9:d7b4:19fb:4926]) by smtp.gmail.com with UTF8SMTPSA id ffacd0b85a97d-48b029be71csm2446492f8f.9.2026.09.30.02.54.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Sep 2026 02:54:04 -0700 (PDT) Date: Wed, 30 Sep 2026 11:54:03 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Thierry Reding Cc: Jonathan Hunter , Mikko Perttunen , Philipp Zabel , linux-pwm@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, "Ola Chr. Vaage" Subject: Re: [PATCH v2 3/3] pwm: tegra: Implement .get_state() Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="y22qctwx6an5bvpv" Content-Disposition: inline In-Reply-To: --y22qctwx6an5bvpv Content-Type: text/plain; protected-headers=v1; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v2 3/3] pwm: tegra: Implement .get_state() MIME-Version: 1.0 Hello Thierry, On Tue, Sep 22, 2026 at 12:07:26PM +0200, Thierry Reding wrote: > On Mon, Sep 21, 2026 at 04:26:03PM +0200, Uwe Kleine-K=F6nig wrote: > > On Mon, Sep 21, 2026 at 12:18:16PM +0200, Thierry Reding wrote: > > > It feels like this has too many assumptions built-in. That's mostly a > > > predefined issue, but I think if we want to get accurate hardware rea= d- > > > out, we need to address this. > > >=20 > > > According to the register documentation, the PWM depth is 16 bits wide > > > (on generations where it can be programmed). The value defaults to 255 > > > (which is n - 1 encoded, hence TEGRA_PWM_DEPTH), but it can technical= ly > > > be reprogrammed to any 16-bit value, as far as I can tell. > > >=20 > > > So I think for this to be correct we'd need to read out the actual va= lue > > > before overwriting with TEGRA_PWM_CSR_0 contents above. At that point= I > > > think we'd need to either adjust the mask to be (2 * depth) - 1, or > > > maybe better yet, avoid masking it out arbitrarily based on the depth > > > and instead cap it at depth so we never exceed the 1:1 ratio for duty > > > cycle vs. period. > >=20 > > As long as .apply() also hardcodes TEGRA_PWM_DEPTH, it's IMO fine that > > .get_state() does so, too. >=20 > Okay, fair enough. Is that an Ack then? Best regards Uwe --y22qctwx6an5bvpv Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEP4GsaTp6HlmJrf7Tj4D7WH0S/k4FAmq83DkACgkQj4D7WH0S /k7y8gf7BWcjviv2MbZpF6/L7O+pa4kJgs74sIcYSavHGEvs1GtV6L0xs2ZEoiTq WBxy04DIWT9xFsxPXj5DUAM0vdu+LDCMq1ZWiioW05IU6znBJrDXUtQ2kuXjDUJ7 xshcSmRoxp4o5AuAowV1BRiYJ/LTva78xhUdtwQAEEYO2NhIr2nNhYXDk76QFv2z +AfILHCm405dcqYt4mYGTdUQX6Lu2+FUS1eA5r7qJHIay5WOZIcalcsVFjnUNnmH EiyG8SdmGBKX9VjsWXtKIkNHrwsZhU+ThyOkkK+h1bkwQIyoospDEDz9b8DaCh3K L+nRCjY0qixI/6UzybWoldwuCnntRg== =5i9Y -----END PGP SIGNATURE----- --y22qctwx6an5bvpv--