Thread (23 messages) flat view 23 messages, 2 authors, 2020-10-08
STALE2137d LANDED

Revision v4 of 4 in this series; landed in mainline as da8f58909e7e on 2020-10-08.

Revisions (4)
  1. v1 [diff vs current]
  2. v2 [diff vs current]
  3. v3 [diff vs current]
  4. v4 current

[PATCH v4 11/21] spi: dw: Unmask IRQs after enabling the chip

From: Serge Semin <hidden>
Date: 2020-10-07 23:56:06
Also in: linux-spi, lkml
Subsystem: spi subsystem, the rest · Maintainers: Mark Brown, Linus Torvalds

It's theoretically erroneous to enable IRQ before the chip is turned on.
If IRQ handler gets executed before the chip is enabled, then any data
written to the Tx FIFO will be just ignored.

I say "theoretically" because we haven't noticed any problem with that,
but let's fix it anyway just in case...

Signed-off-by: Serge Semin <redacted>
---
 drivers/spi/spi-dw-core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
index e7ffcfff6594..89e5428c8de6 100644
--- a/drivers/spi/spi-dw-core.c
+++ b/drivers/spi/spi-dw-core.c
@@ -376,8 +376,6 @@ static int dw_spi_transfer_one(struct spi_controller *master,
 			spi_enable_chip(dws, 1);
 			return ret;
 		}
-	} else {
-		dw_spi_irq_setup(dws);
 	}
 
 	spi_enable_chip(dws, 1);
@@ -385,6 +383,8 @@ static int dw_spi_transfer_one(struct spi_controller *master,
 	if (dws->dma_mapped)
 		return dws->dma_ops->dma_transfer(dws, transfer);
 
+	dw_spi_irq_setup(dws);
+
 	return 1;
 }
 
-- 
2.27.0
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