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 BDF3113E204; Tue, 23 Jan 2024 01:06:34 +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=1705971994; cv=none; b=kunl2/WhpPkdPVbdFO0/zaPmABlOutdVsd7IFjF65lafJ+rfpSFwwSZjfU238JOeHtG9Z4/QHhGj1zQ8zGTtZVwNYcvGlApi/8I+jX5qtGrK8KsJ7UMHnYi2qLuhxUrUb3uszIaUx6U8dXX/rKz14jpyNEvsKeVNlgfjH+YUnUU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705971994; c=relaxed/simple; bh=NEmR8+tGgaUe+Zvo1EhU6y2pggOS5Y4kT50/9EMdNkM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RWdElkkIvrX/tSHVrGhX9hkzph3lSajVjkymS7brzYkimZlv9N67jIkf7UivwpUfFmLdGU/MrjRe7ZfrEubf7BV7lx7ve5AysXMfJnEuf0I7XheEKqfppGA94LOIXMffo2iREKEyrdQvYdF4lSyTNgWdn54eB7usZJNMb5mBWSY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bYrUixxL; 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="bYrUixxL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59E7BC433F1; Tue, 23 Jan 2024 01:06:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1705971994; bh=NEmR8+tGgaUe+Zvo1EhU6y2pggOS5Y4kT50/9EMdNkM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bYrUixxL+6ggjK7eJBWn8IFJIUU7fOBgOkTZlDLZAZBlSjMvDMnrOgkTQ8Tqv0vCR 1W+ONBwxeXq0OXez5iSE5f7kHD3nQGqXDFx7ofkOvEIOEbRIm6vEZpFj6+j8Zq8UEq ied+ae/vdOST4Kda+1y57x07zf8OSlHa5c7MTanA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marek Szyprowski , Chanho Park , Andi Shyti , Wolfram Sang , Sasha Levin Subject: [PATCH 5.10 285/286] i2c: s3c24xx: fix read transfers in polling mode Date: Mon, 22 Jan 2024 15:59:51 -0800 Message-ID: <20240122235743.030995138@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240122235732.009174833@linuxfoundation.org> References: <20240122235732.009174833@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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marek Szyprowski [ Upstream commit 0d9cf23ed55d7ba3ab26d617a3ae507863674c8f ] To properly handle read transfers in polling mode, no waiting for the ACK state is needed as it will never come. Just wait a bit to ensure start state is on the bus and continue processing next bytes. Fixes: 117053f77a5a ("i2c: s3c2410: Add polling mode support") Signed-off-by: Marek Szyprowski Reviewed-by: Chanho Park Reviewed-by: Andi Shyti Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-s3c2410.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index 05831848b7bf..687588834fc8 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -223,8 +223,17 @@ static bool is_ack(struct s3c24xx_i2c *i2c) int tries; for (tries = 50; tries; --tries) { - if (readl(i2c->regs + S3C2410_IICCON) - & S3C2410_IICCON_IRQPEND) { + unsigned long tmp = readl(i2c->regs + S3C2410_IICCON); + + if (!(tmp & S3C2410_IICCON_ACKEN)) { + /* + * Wait a bit for the bus to stabilize, + * delay estimated experimentally. + */ + usleep_range(100, 200); + return true; + } + if (tmp & S3C2410_IICCON_IRQPEND) { if (!(readl(i2c->regs + S3C2410_IICSTAT) & S3C2410_IICSTAT_LASTBIT)) return true; -- 2.43.0