[v2,11/13] i2c: qup: send NACK for last read sub transfers

Message ID	1520860502-14886-12-git-send-email-absahu@codeaurora.org
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Headers	show Return-Path: <linux-i2c-owner@vger.kernel.org> sender: absahu@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 6CFA0603AF; Mon, 12 Mar 2018 13:15:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 6CFA0603AF From: Abhishek Sahu <absahu@codeaurora.org> To: Andy Gross <andy.gross@linaro.org>, Wolfram Sang <wsa@the-dreams.de> Cc: David Brown <david.brown@linaro.org>, Sricharan R <sricharan@codeaurora.org>, Austin Christ <austinwc@codeaurora.org>, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Abhishek Sahu <absahu@codeaurora.org> Subject: [PATCH v2 11/13] i2c: qup: send NACK for last read sub transfers Date: Mon, 12 Mar 2018 18:45:00 +0530 Message-Id: <1520860502-14886-12-git-send-email-absahu@codeaurora.org> In-Reply-To: <1520860502-14886-1-git-send-email-absahu@codeaurora.org> References: <1520860502-14886-1-git-send-email-absahu@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk
Series	Major code reorganization to make all i2c transfers working \| expand [v2,00/13] Major code reorganization to make all i2c transfers working [v2,01/13] i2c: qup: fix copyrights and update to SPDX identifier [v2,02/13] i2c: qup: fixed releasing dma without flush operation completion [v2,03/13] i2c: qup: minor code reorganization for use_dma [v2,04/13] i2c: qup: remove redundant variables for BAM SG count [v2,05/13] i2c: qup: schedule EOT and FLUSH tags at the end of transfer [v2,06/13] i2c: qup: fix the transfer length for BAM RX EOT FLUSH tags [v2,07/13] i2c: qup: proper error handling for i2c error in BAM mode [v2,08/13] i2c: qup: use the complete transfer length to choose DMA mode [v2,09/13] i2c: qup: change completion timeout according to transfer length [v2,10/13] i2c: qup: fix buffer overflow for multiple msg of maximum xfer len [v2,11/13] i2c: qup: send NACK for last read sub transfers [v2,12/13] i2c: qup: reorganization of driver code to remove polling for qup v1 [v2,13/13] i2c: qup: reorganization of driver code to remove polling for qup v2

Message ID

1520860502-14886-12-git-send-email-absahu@codeaurora.org

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Accepted

Headers

DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 6CFA0603AF
From: Abhishek Sahu <absahu@codeaurora.org>
To: Andy Gross <andy.gross@linaro.org>, Wolfram Sang <wsa@the-dreams.de>
Cc: David Brown <david.brown@linaro.org>,
	Sricharan R <sricharan@codeaurora.org>,
	Austin Christ <austinwc@codeaurora.org>,
	linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org,
	linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org,
	Abhishek Sahu <absahu@codeaurora.org>
Subject: [PATCH v2 11/13] i2c: qup: send NACK for last read sub transfers
Date: Mon, 12 Mar 2018 18:45:00 +0530
Message-Id: <1520860502-14886-12-git-send-email-absahu@codeaurora.org>
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Series

Major code reorganization to make all i2c transfers working | expand

Commit Message

Abhishek Sahu March 12, 2018, 1:15 p.m. UTC

According to I2c specification, “If a master-receiver sends a
repeated START condition, it sends a not-acknowledge (A) just
before the repeated START condition”. QUP v2 supports sending
of NACK without stop with QUP_TAG_V2_DATARD_NACK so added the
same.

Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Reviewed-by: Austin Christ <austinwc@codeaurora.org>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
---

* Changes from v1: None

 drivers/i2c/busses/i2c-qup.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
index 5bb7ebe..4ebd922 100644
--- a/drivers/i2c/busses/i2c-qup.c
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -104,6 +104,7 @@ 
 #define QUP_TAG_V2_DATAWR              0x82
 #define QUP_TAG_V2_DATAWR_STOP         0x83
 #define QUP_TAG_V2_DATARD              0x85
+#define QUP_TAG_V2_DATARD_NACK         0x86
 #define QUP_TAG_V2_DATARD_STOP         0x87
 
 /* Status, Error flags */
@@ -606,7 +607,9 @@  static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
 			tags[len++] = QUP_TAG_V2_DATAWR_STOP;
 	} else {
 		if (msg->flags & I2C_M_RD)
-			tags[len++] = QUP_TAG_V2_DATARD;
+			tags[len++] = qup->blk.pos == (qup->blk.count - 1) ?
+				      QUP_TAG_V2_DATARD_NACK :
+				      QUP_TAG_V2_DATARD;
 		else
 			tags[len++] = QUP_TAG_V2_DATAWR;
 	}

[v2,11/13] i2c: qup: send NACK for last read sub transfers

Commit Message

Patch