From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 2CD733DABE3 for ; Thu, 21 May 2026 14:25:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779373560; cv=none; b=KQ0UFQdPJTrp3fbufrVAKpdZESGKnUSr4W+1M4BqZsrdi+ITsZCiPkeU7KvGgGOdKtDwO5Hzc47Vj/Pd7lZUeBAw/nVTgnYNmlc+mxL7lhTHgKZq2/ohsnELd0O3QvlVzmDuBAgFuR4y3iurlYKiUo3jCdX9lK8LP56JxqpSwEI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779373560; c=relaxed/simple; bh=RF7QLC3dpWqeqNwGYR5zwtThAKA0r6Qruqj6ngg8fj0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=B5U6jF3sPTuCCT1hh4JC8sgfVNHdXFnR7ZDOOdWknZZ5YZiHXIf7YEiXG2S6201TeaYD5NXqmuEP28GZQwhNaDvikUnsn4dgntGtoGAjSYdRCmnsyKKpS+VJRF94qghH/qW+l25NvIGTP4IH9yvVUH9GW99ehQ/sThm9oS9kKd4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=HWOBlGud; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=hYEs2aSy; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="HWOBlGud"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="hYEs2aSy" Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 64L99u2P3772827 for ; Thu, 21 May 2026 14:25:58 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= wweDli+iXKrm5zb1x2Qf7TwrvyD4/BWIqGgm65k1Jrw=; b=HWOBlGudAts5tl4O sVdGxaX2/w4NJN5QrH20IfQUAOIm2H5kCoEJmkaXtcWREgMrgU6itwagvqctb5KC e0m7E1rMafipgMuaeaMUZ6Rg8TB0oapFFto0yU8ZkGkTlrds7cPyhwDIH9O2zfu4 AOkUrqG/Z9AoEA6YdGAB0LNxp7DbE4s2XBF+SjALJjImkVedGDW5Q6fKgjZugHvp vEGhwum0nU+1l9S18i3no/5dyxDjgGvOXuRHldL4q3KykeLpOpOcYWCLWAlCSTAx VesChHOSehl7LgIRz4LybwNpkKkbi9WL+vSCCkmokahgSyOGyIMgf9rzw8cPeUiS v4BtWg== Received: from mail-ua1-f71.google.com (mail-ua1-f71.google.com [209.85.222.71]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4e9ma43n7w-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Thu, 21 May 2026 14:25:58 +0000 (GMT) Received: by mail-ua1-f71.google.com with SMTP id a1e0cc1a2514c-95fc647f356so10061658241.3 for ; Thu, 21 May 2026 07:25:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1779373557; x=1779978357; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=wweDli+iXKrm5zb1x2Qf7TwrvyD4/BWIqGgm65k1Jrw=; b=hYEs2aSy/RH1DFZlEC0rEQCKJJ0Q9Tkzb9ZbTn63bHqQ+BeA8tR1v2dFPt0H6w5an0 tjMYPSmzfhz+G62sZArFlQUnWoeHg96tfkNEFDbPf0+PZpmSVZkBynnSUVTry0lP5Xw/ DhWo59X0FY+7uSjl4iOHtYS84AI7z5fNSaYVdPOCXHylJ+dIKksbTqggEhqGgJzV9IBe XT8wvqLNGrPsMfiVW03ruIssIyLYOEscYiCxRTd8hZrDDfxuVr/bsy0n244Ojj1GSM6S UAKaZOVZXeKaXoj43ZqT4c3jZQM+87E7xrDBhu8DfH2hjslEU+rBGVU2DQ8/WqlPUibe GIZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779373557; x=1779978357; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=wweDli+iXKrm5zb1x2Qf7TwrvyD4/BWIqGgm65k1Jrw=; b=BAa9cowRLMvUCS4hC6/Rp/34/Vat4yN8qWw/8SoXAzp6/LsRtSfYGnBh7Q9oQeWqyj q5p84Qg+dht6/mJB9gugN9ziTQsdsLoiMLJx9yWP0tLHG70l8n8J6iqWVUF3S/iVMn0L zlm6iNz81YzDGb7a6Yp/kTcAPcOL970nAlQ4zzKl23uHhGqu7oWM8e3csWd4E0NfaUWz tNgtx9w6ij8PvOi5UOywE8eGFw+O2IMmUpS873CF1H6Yz/olLBVx1dxejElaSF3BjnoL m8JrNAM9+KwP71NoftUCj/sjAEmrUwTCcZQKgbF76NzCJJZ4iKBvZyhBBNFA7dQpYgOb QHhg== X-Gm-Message-State: AOJu0Yx6qYT2jYA/MUSNTvGRxIbHx0NMbUnzjeQVKjuLBJn2ZAOl4sLQ mliHsURkc7PX3nzFaoYCfWBQ3yxuu6FCEsmNEXKgtTNQ2oMkV+614KXQ4n8tSr4W+JZOsm8l2Lx lPGH6foIhVKVlNjTqOFvg4PgmXFQJNA+zcBWOEnrx47VNRLAP1PbQYo5TRwY4I5sldv4= X-Gm-Gg: Acq92OHz3tAY+KbRgpjqz6XKR0LERjAMpyz9mrNRZo5WKX/kl/AXVrmA8PZQgsVvSfU yU1NDzvVpFaSMSQFkGN/bkD2FGncWJE5eIZuzYoyQWhbZRMLEOaKMIvLXc2erMNyjKnPBqLVLmu 6h8FgNGloBHxVTWw+Sr9Gkz892bTKCGze3FCycoejjEOHBc08F9qhvWsldW81uVMXxifpainYmN xYTHtVAOTiiLHOQkObiVHLQw275NoBUaIIeJb33gqfoMqmUOJMXTMrQd4hgC5f3EA4cz/pL2QxP BVSdV+SZaTesHi+9489bzxa/zFoF0SK3UsxUnuGRCtXXLBQcmWXIg7D+I0ajHYP9JF9tIZTbk9A PvnYRmK4fdg6d2Kp3Lud2nsLKXRmdvRK+PlnrqaMn8mO0bfmoMss= X-Received: by 2002:a05:6102:ccf:b0:631:ff40:22b2 with SMTP id ada2fe7eead31-6738d46a283mr1958436137.2.1779373557322; Thu, 21 May 2026 07:25:57 -0700 (PDT) X-Received: by 2002:a05:6102:ccf:b0:631:ff40:22b2 with SMTP id ada2fe7eead31-6738d46a283mr1958390137.2.1779373556733; Thu, 21 May 2026 07:25:56 -0700 (PDT) Received: from brgl-qcom.local ([2a01:cb1d:dc:7e00:bb10:ae82:b7c3:d15a]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4903c9abbadsm30441925e9.8.2026.05.21.07.25.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 May 2026 07:25:56 -0700 (PDT) From: Bartosz Golaszewski Date: Thu, 21 May 2026 16:25:36 +0200 Subject: [PATCH v4 03/10] nvmem: return -EOPNOTSUPP to in-kernel users on missing callbacks Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260521-nvmem-unbind-v4-3-7fa136759491@oss.qualcomm.com> References: <20260521-nvmem-unbind-v4-0-7fa136759491@oss.qualcomm.com> In-Reply-To: <20260521-nvmem-unbind-v4-0-7fa136759491@oss.qualcomm.com> To: Srinivas Kandagatla , Bartosz Golaszewski , Johan Hovold , Loic Poulain Cc: linux-kernel@vger.kernel.org, brgl@kernel.org, Bartosz Golaszewski X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=2819; i=bartosz.golaszewski@oss.qualcomm.com; h=from:subject:message-id; bh=RF7QLC3dpWqeqNwGYR5zwtThAKA0r6Qruqj6ngg8fj0=; b=owEBbQKS/ZANAwAKAQWdLsv/NoTDAcsmYgBqDxXm9SuT/kxxmyGbqJLojGWnPgZR7hepU20qF jgNLIIPCjuJAjMEAAEKAB0WIQSR5RMt5bVGHXuiZfwFnS7L/zaEwwUCag8V5gAKCRAFnS7L/zaE w0D4EACiUxM+Ex7odgYBj/7v1Od31kypiK1paptnkogfn+RF0BJyYLjJowS4e6Y+/rCMj0hd1z5 rpkrfBPR5krjAgxkiURYJJXkz2QPGlzcgeO4Eh4sLhaogpeW8Puuvew9QtyhCzmgkoG3qus1TQz mUvgR9IVQQYqlI9YXHTADoSH084nSTGW+DgDN4cPmnVPcuUvgO0lIKsxsncO8bPot9vjWyZH3s7 hjZdZ+k4dGuqX7W5HcmX1oRtEiI3jia12n8dj7kp7RBZqdpHlbt6zQrPF24vR9YVJTDfYYnrBlr WuVDeCNi3rHWukFYVnD8jh/BGk2bGt4sVzwRzjV2a2fuaxepX3z+TodEKrKPKOm1ItQup4Vwsgm Yl1W+EfZZTgqfda+qxyrQ+HFzHfRqj2UE02VhfTwcX+bmDeOJMQJmEwSFsL0vLKP4QuHGNqRQLb wSKLTAHmD9xAXzGxrwIwCgUlyXPCLlCveTSFAH1Fdhx8B+yhw63GWsVCPKi/b8K8jFDo2n3Bsg7 ZyKHoGgGXL6f/HlsvoyseQMIltJH6b8f7Y/cT04WcZ/3AGwKkSorq2AtQa8Y4HrCQ3+OPwwH+pm okuMEQt6ro2kutElP2ka/wTn9vQS8Nv4Xju8Tjs0f/zMy3Bp9GkZZjp6nxtyAPLCbclWospWdUI B+jZ/R4o9ew+kTA== X-Developer-Key: i=bartosz.golaszewski@oss.qualcomm.com; a=openpgp; fpr=169DEB6C0BC3C46013D2C79F11A72EA01471D772 X-Authority-Analysis: v=2.4 cv=K9kS2SWI c=1 sm=1 tr=0 ts=6a0f15f6 cx=c_pps a=KB4UBwrhAZV1kjiGHFQexw==:117 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=NGcC8JguVDcA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=DJpcGTmdVt4CTyJn9g5Z:22 a=EUspDBNiAAAA:8 a=fMUuWMZ6TpuTS4Z4e9kA:9 a=QEXdDO2ut3YA:10 a=o1xkdb1NAhiiM49bd1HK:22 X-Proofpoint-GUID: DdxYHDvpbWbjeOJJYXH28Nz1hNW_C0J3 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTIxMDE0NCBTYWx0ZWRfX5HbqhYkb6LRA wG2WCyLVuaSZsJHMEc7F4xAugMTuw3qy1eJJPfwGNWrRTgQyefqfam2nOzfGDbLArtpqsW8f6HJ AkS+ZX/C7VvuqX8mVcD7oyLGD1ITpny4vvSYGDKyOL640jTyFnSzluGV6RrLnhQlQ96Ph/dpFZH 23YmICI7eAMFlERROsceIwWOQuf49JIwrWu4B3B4WY3MnwDHCgPwSGoarAy1KEuNu5VYVkkYsW2 Kl9a314nnRKElJGPKFAk6BZeFtxdBIAsDIUNmDESw3YjNUHKzj6mm/Z0bLvVsWLhYoYQIaCLWVp jAl0IBvmEYOnSfjg/4TkK/WkOUGWwNVr6q9ov6RYFQoeBq9hbr0rUr1lEmu2hsXh1l7OlsZZ7eY 1liCAju0wE84e6HdIdtvArzgF21yg/x/3tcjrJqnI5afDsy0V2wLj5to6zG6iEOLya65Tn/xBUz 6cF+Xu1ZP92SyQn2/Qg== X-Proofpoint-ORIG-GUID: DdxYHDvpbWbjeOJJYXH28Nz1hNW_C0J3 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-05-21_02,2026-05-18_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 phishscore=0 bulkscore=0 adultscore=0 priorityscore=1501 impostorscore=0 malwarescore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2605130000 definitions=main-2605210144 __nvmem_reg_read/write() currently return -EINVAL if the relevant callback is not present. User-space helpers again check the presence of the callbacks to see if they should return -EPERM. Ahead of adding SRCU synchronization: change the error code returned to in-kernel users to -EOPNOTSUPP which is more indicative of the actual reason for the failure. Remove the checks from the sysfs attribute callbacks as these are not visible without the required callbacks. Signed-off-by: Bartosz Golaszewski --- drivers/nvmem/core.c | 37 +++++++++++++++++++------------------ 1 file changed, 19 insertions(+), 18 deletions(-) diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index e871181751f3c2739154b3cff27ef9b90032e607..06d7f3d819084579434370cd12c6b263abff196e 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -55,10 +55,10 @@ static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, void *val, size_t bytes) { - if (nvmem->reg_read) - return nvmem->reg_read(nvmem->priv, offset, val, bytes); + if (!nvmem->reg_read) + return -EOPNOTSUPP; - return -EINVAL; + return nvmem->reg_read(nvmem->priv, offset, val, bytes); } static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, @@ -66,14 +66,14 @@ static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, { int ret; - if (nvmem->reg_write) { - gpiod_set_value_cansleep(nvmem->wp_gpio, 0); - ret = nvmem->reg_write(nvmem->priv, offset, val, bytes); - gpiod_set_value_cansleep(nvmem->wp_gpio, 1); - return ret; - } + if (!nvmem->reg_write) + return -EOPNOTSUPP; + + gpiod_set_value_cansleep(nvmem->wp_gpio, 0); + ret = nvmem->reg_write(nvmem->priv, offset, val, bytes); + gpiod_set_value_cansleep(nvmem->wp_gpio, 1); - return -EINVAL; + return ret; } static int nvmem_access_with_keepouts(struct nvmem_device *nvmem, @@ -231,13 +231,12 @@ static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj, count = round_down(count, nvmem->word_size); - if (!nvmem->reg_read) - return -EPERM; - rc = nvmem_reg_read(nvmem, pos, buf, count); - - if (rc) + if (rc) { + if (rc == -EOPNOTSUPP) + return -EPERM; return rc; + } return count; } @@ -264,13 +263,15 @@ static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj, count = round_down(count, nvmem->word_size); - if (!nvmem->reg_write || nvmem->read_only) + if (nvmem->read_only) return -EPERM; rc = nvmem_reg_write(nvmem, pos, buf, count); - - if (rc) + if (rc) { + if (rc == -EOPNOTSUPP) + return -EPERM; return rc; + } return count; } -- 2.47.3