Backport below changes for I2C QUP driver from v4.17: 0668bc44a426 i2c: qup: fix copyrights and update to SPDX identifier 7239872fb340 i2c: qup: fixed releasing dma without flush operation completion eb422b539c1f i2c: qup: minor code reorganization for use_dma 6d5f37f166bb i2c: qup: remove redundant variables for BAM SG count c5adc0fa63a9 i2c: qup: schedule EOT and FLUSH tags at the end of transfer 7e6c35fe602d i2c: qup: fix the transfer length for BAM RX EOT FLUSH tags 3f450d3eea14 i2c: qup: proper error handling for i2c error in BAM mode 08f15963bc75 i2c: qup: use the complete transfer length to choose DMA mode ecb6e1e5f435 i2c: qup: change completion timeout according to transfer length 6f2f0f6465ac i2c: qup: fix buffer overflow for multiple msg of maximum xfer len f7714b4e451b i2c: qup: send NACK for last read sub transfers fbfab1ab0658 i2c: qup: reorganization of driver code to remove polling for qup v1 7545c7dba169 i2c: qup: reorganization of driver code to remove polling for qup v2 This fixes various I2C issues observed on AP120C-AC board equipped with Atmel/Microchip AT97SC3205T TPM module. Tested-by: Christian Lamparter <chunkeey@gmail.com> Signed-off-by: Piotr Dymacz <pepe2k@gmail.com>
		
			
				
	
	
		
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From f7714b4e451bdcb7918b9aad14af22684ceac638 Mon Sep 17 00:00:00 2001
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From: Abhishek Sahu <absahu@codeaurora.org>
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Date: Mon, 12 Mar 2018 18:45:00 +0530
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Subject: [PATCH 11/13] i2c: qup: send NACK for last read sub transfers
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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According to I2c specification, “If a master-receiver sends a
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repeated START condition, it sends a not-acknowledge (A) just
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before the repeated START condition”. QUP v2 supports sending
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of NACK without stop with QUP_TAG_V2_DATARD_NACK so added the
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same.
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Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
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Reviewed-by: Austin Christ <austinwc@codeaurora.org>
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Reviewed-by: Andy Gross <andy.gross@linaro.org>
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Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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---
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 drivers/i2c/busses/i2c-qup.c | 5 ++++-
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 1 file changed, 4 insertions(+), 1 deletion(-)
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--- a/drivers/i2c/busses/i2c-qup.c
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+++ b/drivers/i2c/busses/i2c-qup.c
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@@ -104,6 +104,7 @@
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 #define QUP_TAG_V2_DATAWR              0x82
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 #define QUP_TAG_V2_DATAWR_STOP         0x83
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 #define QUP_TAG_V2_DATARD              0x85
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+#define QUP_TAG_V2_DATARD_NACK         0x86
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 #define QUP_TAG_V2_DATARD_STOP         0x87
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 /* Status, Error flags */
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@@ -606,7 +607,9 @@ static int qup_i2c_set_tags(u8 *tags, st
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 			tags[len++] = QUP_TAG_V2_DATAWR_STOP;
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 	} else {
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 		if (msg->flags & I2C_M_RD)
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-			tags[len++] = QUP_TAG_V2_DATARD;
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+			tags[len++] = qup->blk.pos == (qup->blk.count - 1) ?
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+				      QUP_TAG_V2_DATARD_NACK :
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+				      QUP_TAG_V2_DATARD;
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 		else
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 			tags[len++] = QUP_TAG_V2_DATAWR;
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 	}
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