diff mbox

[6/6] spi/ath79: add shutdown handler

Message ID 1356601349-23617-7-git-send-email-juhosg@openwrt.org (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Gabor Juhos Dec. 27, 2012, 9:42 a.m. UTC
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@openwrt.org>
---
 drivers/spi/spi-ath79.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

Comments

Grant Likely Feb. 5, 2013, 1:02 p.m. UTC | #1
On Thu, 27 Dec 2012 10:42:29 +0100, Gabor Juhos <juhosg@openwrt.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@openwrt.org>
> ---
>  drivers/spi/spi-ath79.c |   12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c
> index 842acd8..73e491e 100644
> --- a/drivers/spi/spi-ath79.c
> +++ b/drivers/spi/spi-ath79.c
> @@ -293,7 +293,7 @@ err_put_master:
>  	return ret;
>  }
>  
> -static int ath79_spi_remove(struct platform_device *pdev)
> +static void __ath79_spi_remove(struct platform_device *pdev)
>  {
>  	struct ath79_spi *sp = platform_get_drvdata(pdev);
>  
> @@ -304,13 +304,23 @@ static int ath79_spi_remove(struct platform_device *pdev)
>  	iounmap(sp->base);
>  	platform_set_drvdata(pdev, NULL);
>  	spi_master_put(sp->bitbang.master);
> +}
>  
> +static int ath79_spi_remove(struct platform_device *pdev)
> +{
> +	__ath79_spi_remove(pdev);
>  	return 0;
>  }
>  
> +static void ath79_spi_shutdown(struct platform_device *pdev)
> +{
> +	__ath79_spi_remove(pdev);
> +}

Just call ath79_spi_remote(pdev) directly from ath79_spi_shutdown(). No
need for the extra hook and __ version of the original function.

g.


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Gabor Juhos Feb. 5, 2013, 7:53 p.m. UTC | #2
2013.02.05. 14:02 keltezéssel, Grant Likely írta:

>> -static int ath79_spi_remove(struct platform_device *pdev)
>> +static void __ath79_spi_remove(struct platform_device *pdev)
>>  {
>>  	struct ath79_spi *sp = platform_get_drvdata(pdev);
>>  
>> @@ -304,13 +304,23 @@ static int ath79_spi_remove(struct platform_device *pdev)
>>  	iounmap(sp->base);
>>  	platform_set_drvdata(pdev, NULL);
>>  	spi_master_put(sp->bitbang.master);
>> +}
>>  
>> +static int ath79_spi_remove(struct platform_device *pdev)
>> +{
>> +	__ath79_spi_remove(pdev);
>>  	return 0;
>>  }
>>  
>> +static void ath79_spi_shutdown(struct platform_device *pdev)
>> +{
>> +	__ath79_spi_remove(pdev);
>> +}
> 
> Just call ath79_spi_remote(pdev) directly from ath79_spi_shutdown(). No
> need for the extra hook and __ version of the original function.

Ok, I will send a modified patch.

Thanks,
Gabor

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diff mbox

Patch

diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c
index 842acd8..73e491e 100644
--- a/drivers/spi/spi-ath79.c
+++ b/drivers/spi/spi-ath79.c
@@ -293,7 +293,7 @@  err_put_master:
 	return ret;
 }
 
-static int ath79_spi_remove(struct platform_device *pdev)
+static void __ath79_spi_remove(struct platform_device *pdev)
 {
 	struct ath79_spi *sp = platform_get_drvdata(pdev);
 
@@ -304,13 +304,23 @@  static int ath79_spi_remove(struct platform_device *pdev)
 	iounmap(sp->base);
 	platform_set_drvdata(pdev, NULL);
 	spi_master_put(sp->bitbang.master);
+}
 
+static int ath79_spi_remove(struct platform_device *pdev)
+{
+	__ath79_spi_remove(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,