openwrt/target/linux/ipq806x/patches-4.4/714-spi-qup-properly-detect-extra-interrupts.patch
Stijn Tintel 8072264b96 kernel: update kernel 4.4 to version 4.4.19
Refresh patches for all targets that support kernel 4.4.
Compile-tested on all targets that use kernel 4.4 and aren't marked broken.
Runtime-tested on ar71xx, octeon and x86/64.

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
2016-08-23 10:51:17 +03:00

63 lines
2.1 KiB
Diff

From b69e5e855aaae2dd9f7fc6f4a40af8e6e0cf98ee Mon Sep 17 00:00:00 2001
From: Matthew McClintock <mmcclint@codeaurora.org>
Date: Thu, 10 Mar 2016 16:44:55 -0600
Subject: [PATCH] spi: qup: properly detect extra interrupts
It's possible for a SPI transaction to complete and get another
interrupt and have it processed on the same spi_transfer before the
transfer_one can set it to NULL.
This masks unexpected interrupts, so let's set the spi_transfer to
NULL in the interrupt once the transaction is done. So we can
properly detect these bad interrupts and print warning messages.
Change-Id: I0e70ed59fb50e5c48a72a38f74bd178b17c9f24d
Signed-off-by: Matthew McClintock <mmcclint@codeaurora.org>
---
drivers/spi/spi-qup.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -509,6 +509,7 @@ static irqreturn_t spi_qup_qup_irq(int i
u32 opflags, qup_err, spi_err;
unsigned long flags;
int error = 0;
+ bool done = 0;
spin_lock_irqsave(&controller->lock, flags);
xfer = controller->xfer;
@@ -567,16 +568,19 @@ static irqreturn_t spi_qup_qup_irq(int i
spi_qup_write(controller, xfer);
}
- spin_lock_irqsave(&controller->lock, flags);
- controller->error = error;
- controller->xfer = xfer;
- spin_unlock_irqrestore(&controller->lock, flags);
-
/* re-read opflags as flags may have changed due to actions above */
opflags = readl_relaxed(controller->base + QUP_OPERATIONAL);
if ((controller->rx_bytes == xfer->len &&
(opflags & QUP_OP_MAX_INPUT_DONE_FLAG)) || error)
+ done = true;
+
+ spin_lock_irqsave(&controller->lock, flags);
+ controller->error = error;
+ controller->xfer = done ? NULL : xfer;
+ spin_unlock_irqrestore(&controller->lock, flags);
+
+ if (done)
complete(&controller->done);
return IRQ_HANDLED;
@@ -769,7 +773,6 @@ static int spi_qup_transfer_one(struct s
exit:
spi_qup_set_state(controller, QUP_STATE_RESET);
spin_lock_irqsave(&controller->lock, flags);
- controller->xfer = NULL;
if (!ret)
ret = controller->error;
spin_unlock_irqrestore(&controller->lock, flags);