From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 67F90253B71; Tue, 29 Apr 2025 19:51:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745956309; cv=none; b=IxEe6Io97aEAqOdZ1GrDJ6NMsIJ4geZqOV9Jz8JjwLgdmXGx+26jaOalFIvfSgpiiHwfSfGzF5gfCN3mSbByqoL3LrMt9f5SuT2fit0I8VhS0JJ5M6cqaHW4cDfEtlu1wN9y2crhaCuy2gnp0J//juqEX3qwBfj4Z985sdhzj78= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745956309; c=relaxed/simple; bh=z1fvvieY1psn6GVNY6iDPpzBM5AWRCz/GzQ7g8pEEVc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uVvhJRh4noxiSgt0W6sSMZLWtc+LwGlEAzkGZzjNqK7rEpfBV0i2YjsY53HVySAudVPaYuGYB4kosBNn2YqoYJd5p9cgallG4xvLztfujPQLTS5fSDv1ZpCP0YvB6KtTrltuk5etmY4tskjKedP+nMAvgif35eh0xJxMY+wl84s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=b1Wver2v; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="b1Wver2v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E3EC3C4CEE3; Tue, 29 Apr 2025 19:51:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745956308; bh=z1fvvieY1psn6GVNY6iDPpzBM5AWRCz/GzQ7g8pEEVc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=b1Wver2vES19Qwkp6AQZn80UfAWt/dCb+ZdPRTAu9+7Wr9f/3iShWlqG58YB+VX50 dc1NbF3NmgotoSlA+EZnjAwc/hoXuGN97GWgYEr7fq5RofHVRZ0bNd/PPOuZ/BRRfs tBt8BDpU3F7i/2Jh+QjudJkaHx2uSs34ekHrTgYOq1m8CjFJR178bDapZGhUMRqC20 TtSs3RxPwOOL+xndT8Gs+PFfQx+9Vj26jmrIuqdfM8olXCBmHkHMBF68lDay9OmIRI zSZnQFtP46/bDUxxmpDl4qRVBLZTuMzN9qA9dYHjZPPwfbveE1OZk+3NmQi4avqU5b KW5mBSc8SzP0g== Date: Tue, 29 Apr 2025 20:51:42 +0100 From: Srinivas Kandagatla To: =?iso-8859-1?Q?Andr=E9?= Draszik Cc: Lee Jones , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Linus Walleij , Bartosz Golaszewski , Kees Cook , "Gustavo A. R. Silva" , Peter Griffin , Tudor Ambarus , Will McVicker , kernel-team@android.com, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-gpio@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH v8 6/6] nvmem: max77759: add Maxim MAX77759 NVMEM driver Message-ID: References: <20250429-max77759-mfd-v8-0-72d72dc79a1f@linaro.org> <20250429-max77759-mfd-v8-6-72d72dc79a1f@linaro.org> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250429-max77759-mfd-v8-6-72d72dc79a1f@linaro.org> On Tue, Apr 29, 2025 at 09:21:42AM +0100, André Draszik wrote: > The Maxim MAX77759 is a companion PMIC for USB Type-C applications and > includes Battery Charger, Fuel Gauge, temperature sensors, USB Type-C > Port Controller (TCPC), NVMEM, and a GPIO expander. > > This driver exposes the non volatile memory using the platform device > registered by the core MFD driver. > > Signed-off-by: André Draszik > --- > v8: > * replace MODULE_ALIAS() with .id_table (Krzysztof) > * drop previous tags > > v5: > * follow API updates of max77759 core driver > > v2: > * align sentinel in max77759_nvmem_of_id[] with other max77759 drivers > (Christophe) > --- > MAINTAINERS | 1 + > drivers/nvmem/Kconfig | 12 +++ > drivers/nvmem/Makefile | 2 + > drivers/nvmem/max77759-nvmem.c | 162 +++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 177 insertions(+) > > diff --git a/MAINTAINERS b/MAINTAINERS > index 0db5e1fe64930e85265913e6a7dd2669c645cf42..b821502afc48f95d48fb8c6ac6941d1dd8e63582 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -14670,6 +14670,7 @@ S: Maintained > F: Documentation/devicetree/bindings/*/maxim,max77759*.yaml > F: drivers/gpio/gpio-max77759.c > F: drivers/mfd/max77759.c > +F: drivers/nvmem/max77759-nvmem.c > F: include/linux/mfd/max77759.h > > MAXIM MAX77802 PMIC REGULATOR DEVICE DRIVER > diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig > index 8671b7c974b933e147154bb40b5d41b5730518d2..3de07ef524906ad24a89e58abdfe93529a83c80f 100644 > --- a/drivers/nvmem/Kconfig > +++ b/drivers/nvmem/Kconfig > @@ -154,6 +154,18 @@ config NVMEM_LPC18XX_OTP > To compile this driver as a module, choose M here: the module > will be called nvmem_lpc18xx_otp. > > +config NVMEM_MAX77759 > + tristate "Maxim Integrated MAX77759 NVMEM Support" > + depends on MFD_MAX77759 > + default MFD_MAX77759 > + help > + Say Y here to include support for the user-accessible storage found > + in Maxim Integrated MAX77759 PMICs. This IC provides space for 30 > + bytes of storage. > + > + This driver can also be built as a module. If so, the module > + will be called nvmem-max77759. > + > config NVMEM_MESON_EFUSE > tristate "Amlogic Meson GX eFuse Support" > depends on (ARCH_MESON || COMPILE_TEST) && MESON_SM > diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile > index 5b77bbb6488bf89bfb305750a1cbf4a6731a0a58..a9d03cfbbd27e68d40f8c330e72e20378b12a481 100644 > --- a/drivers/nvmem/Makefile > +++ b/drivers/nvmem/Makefile > @@ -34,6 +34,8 @@ obj-$(CONFIG_NVMEM_LPC18XX_EEPROM) += nvmem_lpc18xx_eeprom.o > nvmem_lpc18xx_eeprom-y := lpc18xx_eeprom.o > obj-$(CONFIG_NVMEM_LPC18XX_OTP) += nvmem_lpc18xx_otp.o > nvmem_lpc18xx_otp-y := lpc18xx_otp.o > +obj-$(CONFIG_NVMEM_MAX77759) += nvmem-max77759.o > +nvmem-max77759-y := max77759-nvmem.o > obj-$(CONFIG_NVMEM_MESON_EFUSE) += nvmem_meson_efuse.o > nvmem_meson_efuse-y := meson-efuse.o > obj-$(CONFIG_NVMEM_MESON_MX_EFUSE) += nvmem_meson_mx_efuse.o > diff --git a/drivers/nvmem/max77759-nvmem.c b/drivers/nvmem/max77759-nvmem.c > new file mode 100644 > index 0000000000000000000000000000000000000000..df7d1998fa2f116450d2fd50eba70d9b61a24574 > --- /dev/null > +++ b/drivers/nvmem/max77759-nvmem.c > @@ -0,0 +1,162 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +// > +// Copyright 2020 Google Inc > +// Copyright 2025 Linaro Ltd. > +// > +// NVMEM driver for Maxim MAX77759 > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define MAX77759_NVMEM_OPCODE_HEADER_LEN 3 > +/* > + * NVMEM commands have a three byte header (which becomes part of the command), > + * so we need to subtract that. > + */ > +#define MAX77759_NVMEM_SIZE (MAX77759_MAXQ_OPCODE_MAXLENGTH \ > + - MAX77759_NVMEM_OPCODE_HEADER_LEN) > + > +struct max77759_nvmem { > + struct device *dev; > + struct max77759 *max77759; > +}; > + > +static bool max77759_nvmem_is_valid(unsigned int offset, size_t bytes) > +{ > + return (offset + bytes - 1 <= MAX77759_NVMEM_SIZE); > +} Do you really need this check? nvmem core should take care of this boundary checks. > + > +static int max77759_nvmem_reg_read(void *priv, unsigned int offset, > + void *val, size_t bytes) > +{ > + struct max77759_nvmem *nvmem = priv; > + DEFINE_FLEX(struct max77759_maxq_command, cmd, cmd, length, > + MAX77759_NVMEM_OPCODE_HEADER_LEN); > + DEFINE_FLEX(struct max77759_maxq_response, rsp, rsp, length, > + MAX77759_MAXQ_OPCODE_MAXLENGTH); > + int ret; > + > + if (!max77759_nvmem_is_valid(offset, bytes)) { > + dev_err(nvmem->dev, "outside NVMEM area: %u / %zu\n", > + offset, bytes); > + return -EINVAL; > + } > +