[PATCH v2] spi/ath79: add shutdown handler

[PATCH v2] spi/ath79: add shutdown handler

[Gabor Juhos]

The SPI controller of the AR7xxx/AR9xxx SoCs
have a special mode which allows the SoC to
directly read data from SPI flash chips. In
this mode, the content of the SPI flash chip
can be accessed via a memory mapped region.

During early init time, the kernel expects
that the flash chip is accessible through
that memory region because it reads board
specific values (e.g. MAC address, WiFi
calibration data) from the flash on various
boards.

This is working if the kernel is loaded
directly by the bootloader because that
leaves the SPI controller in the special
mode. However it is not working in a kexec'd
kernel because the SPI driver does not restore
the special mode during shutdown.

The patch adds a shutdown handler to fix this
issue.

Signed-off-by: Gabor Juhos <juhosg-p3rKhJxN3npAfugRpC6u6w@public.gmane.org>
---
Changes since v1:
 - call ath79_spi_remote(pdev) directly from ath79_spi_shutdown()
---
 drivers/spi/spi-ath79.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c
index 842acd8..e504b76 100644
--- a/drivers/spi/spi-ath79.c
+++ b/drivers/spi/spi-ath79.c
@@ -308,9 +308,15 @@ static int ath79_spi_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static void ath79_spi_shutdown(struct platform_device *pdev)
+{
+	ath79_spi_remove(pdev);
+}
+
 static struct platform_driver ath79_spi_driver = {
 	.probe		= ath79_spi_probe,
 	.remove		= ath79_spi_remove,
+	.shutdown	= ath79_spi_shutdown,
 	.driver		= {
 		.name	= DRV_NAME,
 		.owner	= THIS_MODULE,
-- 
1.7.10


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Re: [PATCH v2] spi/ath79: add shutdown handler

[Grant Likely]

On Tue,  5 Feb 2013 20:57:55 +0100, Gabor Juhos <juhosg-p3rKhJxN3npAfugRpC6u6w@public.gmane.org> wrote:
> The SPI controller of the AR7xxx/AR9xxx SoCs
> have a special mode which allows the SoC to
> directly read data from SPI flash chips. In
> this mode, the content of the SPI flash chip
> can be accessed via a memory mapped region.
> 
> During early init time, the kernel expects
> that the flash chip is accessible through
> that memory region because it reads board
> specific values (e.g. MAC address, WiFi
> calibration data) from the flash on various
> boards.
> 
> This is working if the kernel is loaded
> directly by the bootloader because that
> leaves the SPI controller in the special
> mode. However it is not working in a kexec'd
> kernel because the SPI driver does not restore
> the special mode during shutdown.
> 
> The patch adds a shutdown handler to fix this
> issue.
> 
> Signed-off-by: Gabor Juhos <juhosg-p3rKhJxN3npAfugRpC6u6w@public.gmane.org>

Applied, thanks.

g.

> ---
> Changes since v1:
>  - call ath79_spi_remote(pdev) directly from ath79_spi_shutdown()
> ---
>  drivers/spi/spi-ath79.c |    6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c
> index 842acd8..e504b76 100644
> --- a/drivers/spi/spi-ath79.c
> +++ b/drivers/spi/spi-ath79.c
> @@ -308,9 +308,15 @@ static int ath79_spi_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static void ath79_spi_shutdown(struct platform_device *pdev)
> +{
> +	ath79_spi_remove(pdev);
> +}
> +
>  static struct platform_driver ath79_spi_driver = {
>  	.probe		= ath79_spi_probe,
>  	.remove		= ath79_spi_remove,
> +	.shutdown	= ath79_spi_shutdown,
>  	.driver		= {
>  		.name	= DRV_NAME,
>  		.owner	= THIS_MODULE,
> -- 
> 1.7.10
> 

-- 
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.

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and get the hardware for free! Learn more.
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