From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D506EB64D7 for ; Tue, 20 Jun 2023 20:29:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230036AbjFTU3J (ORCPT ); Tue, 20 Jun 2023 16:29:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229843AbjFTU3F (ORCPT ); Tue, 20 Jun 2023 16:29:05 -0400 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D39910F8 for ; Tue, 20 Jun 2023 13:29:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1687292945; x=1718828945; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=xUASsq4735yNa0rqWKigSfGCKuX95XAU6zrjRbcxtJg=; b=UgOu7fBl1N79OCtXnX9nsFJQtQvF5bCBmbKZH5pzzVZeIY5SJTgfVcVw IgXWYtxUwr7LhOV7ze8b/j0SDxuAY2qKtVtzKxZE6HqcvmAXV/82ZVZMP LCCVSmzqlUf9RbnSZkKdp0ysgGtk5GExEsQO0t4NGBvsq65hsuuXj7HPG GwshaxDnQy8Oy1rd8E5eAj9RWIVUay4JwXVVMuJq/uAhYMw1oxPYwsT+M PEWx9+KLwSZU1z1X96dEjvhzvGtWwxVeCpOj8klNtQtS0sBEug61yITnA ZEoGV+tJgI6+el990s3JZZxRbPztw3745Lx2OteaUcm5trRusupKOSEcp w==; X-IronPort-AV: E=McAfee;i="6600,9927,10747"; a="389324644" X-IronPort-AV: E=Sophos;i="6.00,258,1681196400"; d="scan'208";a="389324644" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2023 13:29:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10747"; a="804077879" X-IronPort-AV: E=Sophos;i="6.00,258,1681196400"; d="scan'208";a="804077879" Received: from rhweight-mobl.amr.corp.intel.com (HELO rhweight-mobl.ra.intel.com) ([10.212.240.28]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jun 2023 13:29:04 -0700 From: Russ Weight To: broonie@kernel.org, gregkh@linuxfoundation.org, rafael@kernel.org, linux-kernel@vger.kernel.org Cc: yilun.xu@intel.com, matthew.gerlach@linux.intel.com, Russ Weight Subject: [PATCH 1/1] regmap: spi-avmm: Fix regmap_bus max_raw_write Date: Tue, 20 Jun 2023 13:28:24 -0700 Message-Id: <20230620202824.380313-1-russell.h.weight@intel.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The max_raw_write member of the regmap_spi_avmm_bus structure is defined as: .max_raw_write = SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT SPI_AVMM_VAL_SIZE == 4 and MAX_WRITE_CNT == 1 so this results in a maximum write transfer size of 4 bytes which provides only enough space to transfer the address of the target register. It provides no space for the value to be transferred. This bug became an issue (divide-by-zero in _regmap_raw_write()) after the following was accepted into mainline: commit 3981514180c9 ("regmap: Account for register length when chunking") Change max_raw_write to include space (4 additional bytes) for both the register address and value: .max_raw_write = SPI_AVMM_REG_SIZE + SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT Fixes: 7f9fb67358a2 ("regmap: add Intel SPI Slave to AVMM Bus Bridge support") Reviewed-by: Matthew Gerlach Signed-off-by: Russ Weight --- drivers/base/regmap/regmap-spi-avmm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/regmap/regmap-spi-avmm.c b/drivers/base/regmap/regmap-spi-avmm.c index 4c2b94b3e30b..6af692844c19 100644 --- a/drivers/base/regmap/regmap-spi-avmm.c +++ b/drivers/base/regmap/regmap-spi-avmm.c @@ -660,7 +660,7 @@ static const struct regmap_bus regmap_spi_avmm_bus = { .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, .val_format_endian_default = REGMAP_ENDIAN_NATIVE, .max_raw_read = SPI_AVMM_VAL_SIZE * MAX_READ_CNT, - .max_raw_write = SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT, + .max_raw_write = SPI_AVMM_REG_SIZE + SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT, .free_context = spi_avmm_bridge_ctx_free, }; -- 2.25.1