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Diffstat (limited to 'target/linux/ipq40xx/patches-4.14/088-0011-i2c-qup-send-NACK-for-last-read-sub-transfers.patch')
-rw-r--r--target/linux/ipq40xx/patches-4.14/088-0011-i2c-qup-send-NACK-for-last-read-sub-transfers.patch43
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;
+ }