From nobody Thu Dec 18 21:51:31 2025 Received: from mail-wm1-f53.google.com (mail-wm1-f53.google.com [209.85.128.53]) (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 A8F948BE7 for ; Fri, 14 Jun 2024 14:04:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.53 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718373869; cv=none; b=CizYx7YI/tmWpfkH/yqcIDV55HxEK0FDKKQkmtvxvRz4hzNHyMNTOnRBndODw2V06eCb1yoL/BWHFi1BHgARIHLZlqjU8FlFQSXRbOrgKT+izybbbHfENj2tzmVU/m5UGxx7X/qlBvGqYNfAsBwENUYo7gRqihdMjr6E8er/0xg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718373869; c=relaxed/simple; bh=qMMrvU4twR7lNWCawzecUp5Ntk8orLtchbhEqufOAA0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=U0//eN4QUERasq+jXE/7rG1xZozdfXY11l1+jsDnANXYQsY1vmn9PgfJnxrW2AJ58iCgzAKF1j6Z14VbcmApeQ7k70rozxOjON7rQ/H+MGYyFpppmDRELZlgOyHukWL3FxxmDB4L6ecwDKNe/h2uHM6AaSVWYhBf/TgZimAewCE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=fWAUQZ+I; arc=none smtp.client-ip=209.85.128.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="fWAUQZ+I" Received: by mail-wm1-f53.google.com with SMTP id 5b1f17b1804b1-42189d3c7efso24524185e9.2 for ; Fri, 14 Jun 2024 07:04:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1718373866; x=1718978666; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=tyKkZORkV69x1fE5+eUbWT8nvN2FmJI1dprK8SP21F4=; b=fWAUQZ+IvtPo2CswrmmQ+6dJJc/dY+ibmaFSSzuBkR2vZmsZaxfNcgafVztTrzA+Ym SzxnBlYOz/cV6/ZD0pSMQKEr5FHqnsu5Li5cheBd2ZlLsQWVIbWIGONOJTaYYIFmZW51 LsJ3NVBnQT/c3XgT7EOlol/BY1wXtXGTvB+3lP9A2d1Q15CiFvRwq7qo6o+sb32h8tSO k6Jlkavt6GyyK7ODqbV+TkR6SCex/ULQXQKkyXHi207eK5LC35Bhy/qYwDJYDedIbV56 PmocFTbJUe2cr/oMNPmAZHPHY9T5hUbPT8TpLGstuVWDlbjfuoHM+31S/m8ng2ZwpJv5 doUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718373866; x=1718978666; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=tyKkZORkV69x1fE5+eUbWT8nvN2FmJI1dprK8SP21F4=; b=vGT+VcqZn1lTKAb9SDWWL0g18qeCVxGvXZS0GRPUW/k3kFYpKDJSaBTJwAqVy4pN6f oPh6t6mIEfcTifgRmHsvf7SaMj+yilO69p6gHLyI8X1o9rsh2Dkyqtxlg5ufSjpfvC3T K2q1YAUXIeBugl2faNv4O30v4ADXPtziHDX5R/lppmcPiYMg2ayjK4ftFsGbPhHJMpJz xYpGQasYFkoFSwlTduC6WS1Vyv+UvMhl4Mr4na4PutA3g10zxJ7Z1rH7HFSKdmaEJNCW OtY3acfz/VLKSQkNpPm8nM+fpqxBBkXfy1ldWy9bE1wrmcXljAXYmwIsXyuarbinDlS1 Acyw== X-Forwarded-Encrypted: i=1; AJvYcCXgmU1sUk3iGCp6S5ZWAz7J0TYWJDnFvR8HFFVbPIIzBXiFLK86qrXUAYk4joYNCPFa6LvpyXmh/TuR70feF1ocJIFT6jsdLDNLifI2 X-Gm-Message-State: AOJu0YzYHwtUsyWYY+sdToGvE1JySFuhxwEN7L/RCCnk2Ksiq3h4x45Y famsv7uHAmAHcGd7FpsDYLd0lJnQrH/zxKy8rDsIfMXYspWQ+CLviiaxtrG1iBs= X-Google-Smtp-Source: AGHT+IFzf6VHjgqhRiiyHY4k7GkfYK+2/io9UJpuZFnNRyOb0mR0N0Mlu1xntAskwHBVAR4ighQ1iQ== X-Received: by 2002:a05:600c:3589:b0:423:6b7:55de with SMTP id 5b1f17b1804b1-42306b75a55mr18140005e9.6.1718373866025; Fri, 14 Jun 2024 07:04:26 -0700 (PDT) Received: from gpeter-l.lan ([2a0d:3344:2e8:8510::3aa]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-422f5f33ccesm61310525e9.3.2024.06.14.07.04.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Jun 2024 07:04:25 -0700 (PDT) From: Peter Griffin To: lee@kernel.org, arnd@arndb.de, krzk@kernel.org, alim.akhtar@samsung.com Cc: linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, tudor.ambarus@linaro.org, andre.draszik@linaro.org, saravanak@google.com, willmcvicker@google.com, semen.protsenko@linaro.org, kernel-team@android.com, Peter Griffin Subject: [PATCH 1/2] mfd: syscon: add of_syscon_register_regmap() API Date: Fri, 14 Jun 2024 15:04:20 +0100 Message-ID: <20240614140421.3172674-2-peter.griffin@linaro.org> X-Mailer: git-send-email 2.45.2.627.g7a2c4fd464-goog In-Reply-To: <20240614140421.3172674-1-peter.griffin@linaro.org> References: <20240614140421.3172674-1-peter.griffin@linaro.org> 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 Content-Type: text/plain; charset="utf-8" The of_syscon_register_regmap() API allows an externally created regmap to be registered with syscon. This regmap can then be returned to client drivers using the syscon_regmap_lookup_by_phandle() APIs. The API is used by platforms where mmio access to the syscon registers is not possible, and a underlying soc driver like exynos-pmu provides a SoC specific regmap that can issue a SMC or hypervisor call to write the register. This approach keeps the SoC complexities out of syscon, but allows common drivers such as syscon-poweroff, syscon-reboot and friends that are used by many SoCs already to be re-used. Signed-off-by: Peter Griffin Reviewed-by: Arnd Bergmann Reviewed-by: Sam Protsenko Tested-by: Andr=C3=A9 Draszik --- drivers/mfd/syscon.c | 48 ++++++++++++++++++++++++++++++++++++++ include/linux/mfd/syscon.h | 8 +++++++ 2 files changed, 56 insertions(+) diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index 7d0e91164cba..44991da3ea23 100644 --- a/drivers/mfd/syscon.c +++ b/drivers/mfd/syscon.c @@ -192,6 +192,54 @@ static struct regmap *device_node_get_regmap(struct de= vice_node *np, return syscon->regmap; } =20 +/** + * of_syscon_register_regmap() - Register regmap for specified device node + * @np: Device tree node + * @regmap: Pointer to regmap object + * + * Register an externally created regmap object with syscon for the specif= ied + * device tree node. This regmap can then be returned to client drivers us= ing + * the syscon_regmap_lookup_by_phandle() API. + * + * Return: 0 on success, negative error code on failure. + */ +int of_syscon_register_regmap(struct device_node *np, struct regmap *regma= p) +{ + struct syscon *entry, *syscon =3D NULL; + + if (!np || !regmap) + return -EINVAL; + + /* check if syscon entry already exists */ + spin_lock(&syscon_list_slock); + + list_for_each_entry(entry, &syscon_list, list) + if (entry->np =3D=3D np) { + syscon =3D entry; + break; + } + + spin_unlock(&syscon_list_slock); + + if (syscon) + return -EEXIST; + + syscon =3D kzalloc(sizeof(*syscon), GFP_KERNEL); + if (!syscon) + return -ENOMEM; + + syscon->regmap =3D regmap; + syscon->np =3D np; + + /* register the regmap in syscon list */ + spin_lock(&syscon_list_slock); + list_add_tail(&syscon->list, &syscon_list); + spin_unlock(&syscon_list_slock); + + return 0; +} +EXPORT_SYMBOL_GPL(of_syscon_register_regmap); + struct regmap *device_node_to_regmap(struct device_node *np) { return device_node_get_regmap(np, false); diff --git a/include/linux/mfd/syscon.h b/include/linux/mfd/syscon.h index c315903f6dab..aad9c6b50463 100644 --- a/include/linux/mfd/syscon.h +++ b/include/linux/mfd/syscon.h @@ -28,6 +28,8 @@ struct regmap *syscon_regmap_lookup_by_phandle_args(struc= t device_node *np, unsigned int *out_args); struct regmap *syscon_regmap_lookup_by_phandle_optional(struct device_node= *np, const char *property); +int of_syscon_register_regmap(struct device_node *np, + struct regmap *regmap); #else static inline struct regmap *device_node_to_regmap(struct device_node *np) { @@ -67,6 +69,12 @@ static inline struct regmap *syscon_regmap_lookup_by_pha= ndle_optional( return NULL; } =20 +static inline int of_syscon_register_regmap(struct device_node *np, + struct regmap *regmap) +{ + return -EOPNOTSUPP; +} + #endif =20 #endif /* __LINUX_MFD_SYSCON_H__ */ --=20 2.45.2.627.g7a2c4fd464-goog