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* [PATCH] spi: atmel-quadspi: Disable the QSPI IP at suspend()
@ 2021-02-10 13:54 Tudor Ambarus
  2021-02-11 15:39 ` Mark Brown
  0 siblings, 1 reply; 2+ messages in thread
From: Tudor Ambarus @ 2021-02-10 13:54 UTC (permalink / raw)
  To: broonie
  Cc: nicolas.ferre, alexandre.belloni, ludovic.desroches, linux-spi,
	linux-arm-kernel, linux-kernel, Tudor Ambarus

It is safer to disable the QSPI IP at suspend, in order to avoid
possible impact of glitches on the internal FSMs. This is a theoretical
fix, there were no problems seen as of now. Tested on sama5d2 and
sam9x60 versions of the IP.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 drivers/spi/atmel-quadspi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c
index 10bc5390ab91..95d4fa32c299 100644
--- a/drivers/spi/atmel-quadspi.c
+++ b/drivers/spi/atmel-quadspi.c
@@ -657,6 +657,7 @@ static int __maybe_unused atmel_qspi_suspend(struct device *dev)
 	struct spi_controller *ctrl = dev_get_drvdata(dev);
 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
 
+	atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR);
 	clk_disable_unprepare(aq->qspick);
 	clk_disable_unprepare(aq->pclk);
 
-- 
2.25.1


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2021-02-10 13:54 [PATCH] spi: atmel-quadspi: Disable the QSPI IP at suspend() Tudor Ambarus
2021-02-11 15:39 ` Mark Brown

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