From nobody Mon Feb 9 01:30:01 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 3F1ED219A7C for ; Mon, 7 Apr 2025 17:29:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744046953; cv=none; b=lFWdMF9CXzgT56bbbQZfmANKI+yKXxpLJ/+MVcCPjEEtL9cDHu3901iVA/7IqmED0UiGb2ZJi6O8RWCU9THZ+MGU8T7D5Bs/qNsCOVS12F2C7x4C051PWaMpQV476JDqOsRrnwLxAFmXmOEW0+PuHITSHoc11aIf5hfSaAs9FHc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744046953; c=relaxed/simple; bh=0wCVLf2kJcHvkMdyauZo7zlisXxqfF6avpneNWZUZrk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iTIlYJD81LCDXjcmNocoMdDVa8hWfGFetTDhZa7AtafPiBDxZgSRJLvJm6BSd8RggiPrNC3Q/BElpIFm/T2nJOXNT+no6RZ/s6Vicmsn0jg18rTTCQ+AO0rHAWNm/jNdfU7sOruibYe3E6GdCsTg424cD/jjsYDP6GON00fAG+U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=UWy7WzKx; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UWy7WzKx" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744046949; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=B0fBe2C1irn6omk1B6zTSlR0v1B01FIR0IrpHCwK7Uw=; b=UWy7WzKxm1vt6NlbDmgBpeMfM/azCb3jM4+WbLduQR5FLIYID8GzqT0PjfoiaVTXq9aSip YQvMClM5uirx0YB+SPAp/vHzkaVl5n/cRbzQjjo4yYAJVYq4c2gWKXzrbkUjLWKNPYiD8Z 4uIEES6XQccmM9uCfAX1xYc3cULIO0Q= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-567-VGIaxfc_Ni6Rk6NM9QXflw-1; Mon, 07 Apr 2025 13:29:05 -0400 X-MC-Unique: VGIaxfc_Ni6Rk6NM9QXflw-1 X-Mimecast-MFC-AGG-ID: VGIaxfc_Ni6Rk6NM9QXflw_1744046943 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id D342F1801A07; Mon, 7 Apr 2025 17:29:02 +0000 (UTC) Received: from p16v.luc.cera.cz (unknown [10.44.32.4]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 02A43180B488; Mon, 7 Apr 2025 17:28:56 +0000 (UTC) From: Ivan Vecera To: netdev@vger.kernel.org Cc: Michal Schmidt , Vadim Fedorenko , Arkadiusz Kubalewski , Jiri Pirko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Prathosh Satish , Lee Jones , Kees Cook , Andy Shevchenko , Andrew Morton , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH 03/28] mfd: zl3073x: Add register access helpers Date: Mon, 7 Apr 2025 19:28:30 +0200 Message-ID: <20250407172836.1009461-4-ivecera@redhat.com> In-Reply-To: <20250407172836.1009461-1-ivecera@redhat.com> References: <20250407172836.1009461-1-ivecera@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Content-Type: text/plain; charset="utf-8" Add helpers zl3073x_{read,write}_reg() to access device registers. These functions have to be called with device lock that can be taken by zl3073x_{lock,unlock}() or a caller can use defined guard. Reviewed-by: Michal Schmidt Signed-off-by: Ivan Vecera --- drivers/mfd/zl3073x-core.c | 88 +++++++++++++++++++++++++++++++++++++ include/linux/mfd/zl3073x.h | 32 ++++++++++++++ 2 files changed, 120 insertions(+) diff --git a/drivers/mfd/zl3073x-core.c b/drivers/mfd/zl3073x-core.c index 71454f683eab0..39d4c8608a740 100644 --- a/drivers/mfd/zl3073x-core.c +++ b/drivers/mfd/zl3073x-core.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-only =20 #include +#include #include #include "zl3073x.h" =20 @@ -45,6 +46,93 @@ const struct regmap_config *zl3073x_get_regmap_config(vo= id) } EXPORT_SYMBOL_NS_GPL(zl3073x_get_regmap_config, "ZL3073X"); =20 +/** + * zl3073x_read_reg - Read value from device register + * @zldev: device structure pointer + * @reg: register to be read + * @len: number of bytes to read + * @value: pointer to place to store value read from the register + * + * Caller has to hold the device lock that can be obtained + * by zl3073x_lock(). + * + * Returns 0 in case of success or negative value otherwise + */ +int zl3073x_read_reg(struct zl3073x_dev *zldev, unsigned int reg, + unsigned int len, void *value) +{ + u8 buf[6]; + int rc; + + lockdep_assert_held(&zldev->lock); + + rc =3D regmap_bulk_read(zldev->regmap, reg, buf, len); + if (rc) + return rc; + + switch (len) { + case 1: + *(u8 *)value =3D buf[0]; + break; + case 2: + *(u16 *)value =3D get_unaligned_be16(buf); + break; + case 4: + *(u32 *)value =3D get_unaligned_be32(buf); + break; + case 6: + *(u64 *)value =3D get_unaligned_be48(buf); + break; + default: + WARN(true, "Unsupported register size: %u\n", len); + break; + } + + return rc; +} +EXPORT_SYMBOL_GPL(zl3073x_read_reg); + +/** + * zl3073x_write_reg - Write value to device register + * @zldev: device structure pointer + * @reg: register to be written + * @len: number of bytes to write + * @value: pointer to value to write to the register + * + * Caller has to hold the device lock that can be obtained + * by zl3073x_lock(). + * + * Returns 0 in case of success or negative value otherwise + */ +int zl3073x_write_reg(struct zl3073x_dev *zldev, unsigned int reg, + unsigned int len, const void *value) +{ + u8 buf[6]; + + lockdep_assert_held(&zldev->lock); + + switch (len) { + case 1: + buf[0] =3D *(u8 *)value; + break; + case 2: + put_unaligned_be16(*(u16 *)value, buf); + break; + case 4: + put_unaligned_be32(*(u32 *)value, buf); + break; + case 6: + put_unaligned_be48(*(u64 *)value, buf); + break; + default: + WARN(true, "Unsupported register size: %u\n", len); + break; + } + + return regmap_bulk_write(zldev->regmap, reg, buf, len); +} +EXPORT_SYMBOL_GPL(zl3073x_write_reg); + static const struct devlink_ops zl3073x_devlink_ops =3D { }; =20 diff --git a/include/linux/mfd/zl3073x.h b/include/linux/mfd/zl3073x.h index 7b80c3059b5f3..0156f9044d79d 100644 --- a/include/linux/mfd/zl3073x.h +++ b/include/linux/mfd/zl3073x.h @@ -12,4 +12,36 @@ struct zl3073x_dev { struct mutex lock; }; =20 +/** + * zl3073x_lock - Lock the device + * @zldev: device structure pointer + * + * Caller has to take this lock when it needs to access device registers. + */ +static inline void zl3073x_lock(struct zl3073x_dev *zldev) +{ + mutex_lock(&zldev->lock); +} + +/** + * zl3073x_unlock - Unlock the device + * @zldev: device structure pointer + * + * Caller unlocks the device when it does not need to access device + * registers anymore. + */ +static inline void zl3073x_unlock(struct zl3073x_dev *zldev) +{ + mutex_unlock(&zldev->lock); +} + +DEFINE_GUARD(zl3073x, struct zl3073x_dev *, zl3073x_lock(_T), + zl3073x_unlock(_T)); + +int zl3073x_read_reg(struct zl3073x_dev *zldev, unsigned int reg, + unsigned int len, void *value); + +int zl3073x_write_reg(struct zl3073x_dev *zldev, unsigned int reg, + unsigned int len, const void *value); + #endif /* __LINUX_MFD_ZL3073X_H */ --=20 2.48.1