[PATCH v1 1/2] dmaengine: tegra-apb: Don't save/restore IRQ flags in interrupt handler

From: Dmitry Osipenko
Date: Thu Mar 19 2020 - 16:53:28 EST


The interrupt is already disabled while interrupt handler is running, and
thus, there is no need to save/restore the IRQ flags within the spinlock.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/dma/tegra20-apb-dma.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 4e295d121be6..26f427e02369 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -672,10 +672,9 @@ static void tegra_dma_tasklet(unsigned long data)
static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
{
struct tegra_dma_channel *tdc = dev_id;
- unsigned long flags;
u32 status;

- spin_lock_irqsave(&tdc->lock, flags);
+ spin_lock(&tdc->lock);

trace_tegra_dma_isr(&tdc->dma_chan, irq);
status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS);
@@ -683,11 +682,11 @@ static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
tdc->isr_handler(tdc, false);
tasklet_schedule(&tdc->tasklet);
- spin_unlock_irqrestore(&tdc->lock, flags);
+ spin_unlock(&tdc->lock);
return IRQ_HANDLED;
}

- spin_unlock_irqrestore(&tdc->lock, flags);
+ spin_unlock(&tdc->lock);
dev_info(tdc2dev(tdc), "Interrupt already served status 0x%08x\n",
status);

--
2.25.1