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From: Tudor Ambarus <tudor.ambarus@microchip.com>
To: <broonie@kernel.org>
Cc: <nicolas.ferre@microchip.com>, <alexandre.belloni@bootlin.com>,
	<ludovic.desroches@microchip.com>, <linux-spi@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>,
	"Tudor Ambarus" <tudor.ambarus@microchip.com>
Subject: [PATCH] spi: atmel-quadspi: Disable the QSPI IP at suspend()
Date: Wed, 10 Feb 2021 15:54:28 +0200	[thread overview]
Message-ID: <20210210135428.204134-1-tudor.ambarus@microchip.com> (raw)

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


WARNING: multiple messages have this Message-ID (diff)
From: Tudor Ambarus <tudor.ambarus@microchip.com>
To: <broonie@kernel.org>
Cc: alexandre.belloni@bootlin.com,
	Tudor Ambarus <tudor.ambarus@microchip.com>,
	linux-kernel@vger.kernel.org, ludovic.desroches@microchip.com,
	linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: [PATCH] spi: atmel-quadspi: Disable the QSPI IP at suspend()
Date: Wed, 10 Feb 2021 15:54:28 +0200	[thread overview]
Message-ID: <20210210135428.204134-1-tudor.ambarus@microchip.com> (raw)

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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             reply	other threads:[~2021-02-10 13:58 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-10 13:54 Tudor Ambarus [this message]
2021-02-10 13:54 ` [PATCH] spi: atmel-quadspi: Disable the QSPI IP at suspend() Tudor Ambarus
2021-02-11 15:39 ` Mark Brown
2021-02-11 15:39   ` Mark Brown

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