diff options
Diffstat (limited to 'target/linux/ipq806x/patches-4.4/714-spi-qup-properly-detect-extra-interrupts.patch')
| -rw-r--r-- | target/linux/ipq806x/patches-4.4/714-spi-qup-properly-detect-extra-interrupts.patch | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-4.4/714-spi-qup-properly-detect-extra-interrupts.patch b/target/linux/ipq806x/patches-4.4/714-spi-qup-properly-detect-extra-interrupts.patch new file mode 100644 index 0000000000..d8a9b31462 --- /dev/null +++ b/target/linux/ipq806x/patches-4.4/714-spi-qup-properly-detect-extra-interrupts.patch @@ -0,0 +1,67 @@ +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(-) + +diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c +index e487416..45e30c7 100644 +--- a/drivers/spi/spi-qup.c ++++ b/drivers/spi/spi-qup.c +@@ -509,6 +509,7 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) + 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 irq, void *dev_id) + 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 spi_master *master, + 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); +-- +2.7.2 + |