ipq40xx: backport I2C QUP driver changes from 4.17

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>

1 files changed, 43 insertions, 0 deletions

diff --git a/target/linux/ipq40xx/patches-4.14/088-0011-i2c-qup-send-NACK-for-last-read-sub-transfers.patch b/target/linux/ipq40xx/patches-4.14/088-0011-i2c-qup-send-NACK-for-last-read-sub-transfers.patch
new file mode 100644
index 0000000000..82973829f1
--- /dev/null
+++ b/target/linux/ipq40xx/patches-4.14/088-0011-i2c-qup-send-NACK-for-last-read-sub-transfers.patch
@@ -0,0 +1,43 @@
+From f7714b4e451bdcb7918b9aad14af22684ceac638 Mon Sep 17 00:00:00 2001
+From: Abhishek Sahu <absahu@codeaurora.org>
+Date: Mon, 12 Mar 2018 18:45:00 +0530
+Subject: [PATCH 11/13] i2c: qup: send NACK for last read sub transfers
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+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>
+Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
+---
+ drivers/i2c/busses/i2c-qup.c | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+--- 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, st
+ 			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;
+ 	}