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 22003B641; Tue, 16 Jul 2024 15:40:56 +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=1721144456; cv=none; b=FNcqTzt6JGL4joRapKoQqpAo8L2WCoHD5lCXSDcfEqU/ljh3iMVDhDNqGTlTSKq19/bV5uwKqZ8mNxjBFU/PXgeJHP0Bq4C8ldj/5ZIl3p5XZigsvLuxFlHtPRX7rduwjze57r6vR4BE+zmdkQfmghV15mOuPk5UjI8wQ8FBNqI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144456; c=relaxed/simple; bh=6cOGXXeICmr4F/t3XQKGMfyymWyHNdIA818gghA7pLE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VoPjAtdKllTBeZKALh60XLw4aLWGD4IMXMo5iN2Gl7eNvk6e+L5VuSbzI+e8PpDDZm59p5rCJMnXftknVZATomPUYVv/pcZjMFMs3uwODi4CJX7NgO/KK9IagIExYRLsNpEgyHme80j5PpHYwux0lGDB/Wi/kZxK5SInQk0QxqY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=s9O4e7yc; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="s9O4e7yc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9946AC116B1; Tue, 16 Jul 2024 15:40:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721144456; bh=6cOGXXeICmr4F/t3XQKGMfyymWyHNdIA818gghA7pLE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s9O4e7yc8zWCNIwQetcmd0YQ3maRm2BYEs/p2kVVbEJbrgLgE0endib6YeWYRqwNN GJNIU+f9VKUBoamzkAw6hiKI0o0UurZUlRa3bOQCdH6+SdcL6AaIfFPZrYt7NpAK3u hZQZn/GOY/wLUQHYUyExteb/ZMR36W63K7B4rqd4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dirk Behme , Geert Uytterhoeven , Wolfram Sang , Andi Shyti , Sasha Levin Subject: [PATCH 5.4 78/78] i2c: rcar: bring hardware to known state when probing Date: Tue, 16 Jul 2024 17:31:50 +0200 Message-ID: <20240716152743.659406897@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716152740.626160410@linuxfoundation.org> References: <20240716152740.626160410@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wolfram Sang [ Upstream commit 4e36c0f20cb1c74c7bd7ea31ba432c1c4a989031 ] When probing, the hardware is not brought into a known state. This may be a problem when a hypervisor restarts Linux without resetting the hardware, leaving an old state running. Make sure the hardware gets initialized, especially interrupts should be cleared and disabled. Reported-by: Dirk Behme Reported-by: Geert Uytterhoeven Closes: https://lore.kernel.org/r/20240702045535.2000393-1-dirk.behme@de.bosch.com Fixes: 6ccbe607132b ("i2c: add Renesas R-Car I2C driver") Signed-off-by: Wolfram Sang Signed-off-by: Andi Shyti Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-rcar.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index d0c4b3019e41e..1327f29f1e93b 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -218,6 +218,14 @@ static void rcar_i2c_init(struct rcar_i2c_priv *priv) } +static void rcar_i2c_reset_slave(struct rcar_i2c_priv *priv) +{ + rcar_i2c_write(priv, ICSIER, 0); + rcar_i2c_write(priv, ICSSR, 0); + rcar_i2c_write(priv, ICSCR, SDBS); + rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ +} + static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv) { int i; @@ -863,11 +871,8 @@ static int rcar_unreg_slave(struct i2c_client *slave) /* ensure no irq is running before clearing ptr */ disable_irq(priv->irq); - rcar_i2c_write(priv, ICSIER, 0); - rcar_i2c_write(priv, ICSSR, 0); + rcar_i2c_reset_slave(priv); enable_irq(priv->irq); - rcar_i2c_write(priv, ICSCR, SDBS); - rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ priv->slave = NULL; @@ -973,7 +978,9 @@ static int rcar_i2c_probe(struct platform_device *pdev) if (ret < 0) goto out_pm_put; - rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ + /* Bring hardware to known state */ + rcar_i2c_init(priv); + rcar_i2c_reset_slave(priv); if (priv->devtype == I2C_RCAR_GEN3) { priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL); -- 2.43.0