From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 B166F5013CC; Mon, 7 Sep 2026 17:06:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788800791; cv=none; b=b/sJadhNh0o7vGSLiUAnIBnFpOYQ/IjalQCMB+g4Myt1clNL5vC5p/bOy7WKiwKqd/uuwK6NtiUhFBH5BhwETG0FobxcMpfYjo75itR6Lcx3QgHOM/HTl4XcIPr5bKaeI4XeD6wKFlfqsWKDA6GZ5DkWthvFJpG1inWA69JnNtI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788800791; c=relaxed/simple; bh=4SblcpUt4qLw3fJRzH1zNGiyhQQlwe5uMxga9VaWMtU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HF+K8/vTbCj4ExNQIxcskqVGnU1NcbCVVIIfzlQR/7hcU4+fvOwIqqxFRrfkLxVt6+uuwPXb1yYTpJjWTOnEw/EzUSV2Qg039qOpcHXbcXwbW3MESEL97WnlHI9HPq2vsNf57sQRkyYZus2OOodnmKOGbIwJjhrijMW8iKVisRI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Z4VNrE9J; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Z4VNrE9J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51B961F00A3A; Mon, 7 Sep 2026 17:06:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788800789; bh=x5Wo6+nafu2gFwEiQ2wRMEtUES99VjBaBkvIlgaAU+A=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Z4VNrE9Jn+0IP9Kp6Kr1RWQOJbohWASG7T4SalvXtYLGZz/ThMsuSmZDkxCeCTDns MqqSQLVXN2aaBlBxTokuOVzZ95vlTl0UdBi9C0mE6NsEjC92TrjUICzedcHapHi9Q0 IXcDDtUn75CKKLdkSVK9UhZ4ea0BTjtPbqfRxqJiQ9KAulFM6qk5g05niEHdeLdv2a Iom9BgtF6cQ1FRis1qgAVTJFHCeUm2yxTyWyikSqSZbNUxYDpvK58E3WVZleTi2CFT Up6CVbbPnAB+I1EQms62BFG5xDVmriE7011YdoFQc8sVV9G3qQXzWi7DvrV8UETvM4 YZY7s13yaDyeA== Date: Mon, 7 Sep 2026 18:06:24 +0100 From: Conor Dooley To: Shashank Maurya Cc: Liam Girdwood , Mark Brown , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Florian Fainelli , Broadcom internal kernel review list , Marek Vasut , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, venkata.valluru@oss.qualcomm.com, Jessica Zhang Subject: Re: [PATCH v2 2/2] regulator: rpi-panel-v2: Add required vcc-supply support Message-ID: <20260907-ensnare-wanted-e86eeaf770b0@spud> References: <20260907-rpi_reg-v2-0-0c59aa60d31f@oss.qualcomm.com> <20260907-rpi_reg-v2-2-0c59aa60d31f@oss.qualcomm.com> Precedence: bulk X-Mailing-List: devicetree@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="+YZIrFJKHMKrE7Bh" Content-Disposition: inline In-Reply-To: <20260907-rpi_reg-v2-2-0c59aa60d31f@oss.qualcomm.com> --+YZIrFJKHMKrE7Bh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 07, 2026 at 11:16:08AM +0530, Shashank Maurya wrote: > The Raspberry Pi 7" touchscreen panel V2 MCU requires an external power > rail to be enabled before any I2C register access is attempted. Use > devm_regulator_get() to obtain the vcc supply and enable it at the > start of probe. >=20 > Signed-off-by: Shashank Maurya > --- > drivers/regulator/rpi-panel-v2-regulator.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) >=20 > diff --git a/drivers/regulator/rpi-panel-v2-regulator.c b/drivers/regulat= or/rpi-panel-v2-regulator.c > index 30b78aa75ee3..e54d675962e7 100644 > --- a/drivers/regulator/rpi-panel-v2-regulator.c > +++ b/drivers/regulator/rpi-panel-v2-regulator.c > @@ -11,6 +11,7 @@ > #include > #include > #include > +#include > =20 > /* I2C registers of the microcontroller. */ > #define REG_ID 0x01 > @@ -66,10 +67,21 @@ static int rpi_panel_v2_i2c_probe(struct i2c_client *= i2c) > .parent =3D &i2c->dev, > .reg_set_base =3D REG_POWERON, > }; > + struct regulator *vcc; > struct regmap *regmap; > struct pwm_chip *pc; > int ret; > =20 > + vcc =3D devm_regulator_get(&i2c->dev, "vcc"); > + if (IS_ERR(vcc)) > + return dev_err_probe(&i2c->dev, PTR_ERR(vcc), > + "Failed to get vcc supply\n"); > + > + ret =3D regulator_enable(vcc); > + if (ret) > + return dev_err_probe(&i2c->dev, ret, > + "Failed to enable vcc supply\n"); This needs to be optional, because without it you'll break existing devicetrees. Unless you can explain how all existing users are nonfunctional (e.g. nothing ever enabled the supply, which seems doubtful given this surely worked when it was added) this must remain optional. > + > pc =3D devm_pwmchip_alloc(&i2c->dev, 1, 0); > if (IS_ERR(pc)) > return PTR_ERR(pc); >=20 > --=20 > 2.34.1 >=20 --+YZIrFJKHMKrE7Bh Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCap7vEAAKCRB4tDGHoIJi 0kslAQCRSNBPfFTOdOPa6RoPXdEO5NK95OlBE6pLnHapjVTsVQD+K6YXHc+BsFa0 BcF0yXOQpfUgKdiblUf12moIT4kd4g8= =h7KC -----END PGP SIGNATURE----- --+YZIrFJKHMKrE7Bh--