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 [thread overview]
Message-ID: <1520860502-14886-12-git-send-email-absahu@codeaurora.org> (raw)
In-Reply-To: <1520860502-14886-1-git-send-email-absahu@codeaurora.org>
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;
}
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
next prev parent reply other threads:[~2018-03-12 13:15 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-12 13:14 [PATCH v2 00/13] Major code reorganization to make all i2c transfers working Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 01/13] i2c: qup: fix copyrights and update to SPDX identifier Abhishek Sahu
2018-03-17 20:33 ` Wolfram Sang
2018-03-19 6:21 ` Abhishek Sahu
2018-03-24 12:17 ` Wolfram Sang
2018-03-12 13:14 ` [PATCH v2 02/13] i2c: qup: fixed releasing dma without flush operation completion Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 03/13] i2c: qup: minor code reorganization for use_dma Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 04/13] i2c: qup: remove redundant variables for BAM SG count Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 05/13] i2c: qup: schedule EOT and FLUSH tags at the end of transfer Abhishek Sahu
2018-03-15 6:53 ` Sricharan R
2018-03-12 13:14 ` [PATCH v2 06/13] i2c: qup: fix the transfer length for BAM RX EOT FLUSH tags Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 07/13] i2c: qup: proper error handling for i2c error in BAM mode Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 08/13] i2c: qup: use the complete transfer length to choose DMA mode Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 09/13] i2c: qup: change completion timeout according to transfer length Abhishek Sahu
2018-03-12 13:14 ` [PATCH v2 10/13] i2c: qup: fix buffer overflow for multiple msg of maximum xfer len Abhishek Sahu
2018-03-12 13:15 ` Abhishek Sahu [this message]
2018-03-12 13:15 ` [PATCH v2 12/13] i2c: qup: reorganization of driver code to remove polling for qup v1 Abhishek Sahu
2018-03-13 7:28 ` Sricharan R
2018-03-12 13:15 ` [PATCH v2 13/13] i2c: qup: reorganization of driver code to remove polling for qup v2 Abhishek Sahu
2018-03-13 7:49 ` Sricharan R
2018-03-13 21:09 ` [PATCH v2 00/13] Major code reorganization to make all i2c transfers working Christ, Austin
2018-03-13 21:17 ` Wolfram Sang
2018-03-13 22:12 ` Christ, Austin
2018-03-15 12:46 ` Abhishek Sahu
2018-03-17 20:37 ` Wolfram Sang
2018-03-17 20:40 ` Wolfram Sang
2018-03-24 12:22 ` Wolfram Sang
2018-03-26 4:41 ` Abhishek Sahu
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