ipq806x: add v4.9 support

[openwrt/openwrt.git] / target / linux / ipq806x / patches-4.9 / 0010-spi-qup-properly-detect-extra-interrupts.patch

diff --git a/target/linux/ipq806x/patches-4.9/0010-spi-qup-properly-detect-extra-interrupts.patch b/target/linux/ipq806x/patches-4.9/0010-spi-qup-properly-detect-extra-interrupts.patch
new file mode 100644 (file)
index 0000000..74ef25a
--- /dev/null
+++ b/target/linux/ipq806x/patches-4.9/0010-spi-qup-properly-detect-extra-interrupts.patch
@@ -0,0 +1,61 @@
+From 543618f5388d487ba88e3d5304c161fc3ccf61d1 Mon Sep 17 00:00:00 2001
+From: Matthew McClintock <mmcclint@codeaurora.org>
+Date: Thu, 10 Mar 2016 16:44:55 -0600
+Subject: [PATCH 10/37] 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.
+
+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
+@@ -507,6 +507,7 @@ 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;
+@@ -565,16 +566,19 @@ 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;
+@@ -767,7 +771,6 @@ 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);