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[PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform

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  [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform Duc Dang <dhdang@apm.com> - 2015-08-08 03:10 +0200
    Re: [PATCH v4 2/2] usb: Add support for ACPI identification to  xhci-platform Greg KH <gregkh@linuxfoundation.org> - 2015-08-08 03:30 +0200
      Re: [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform Duc Dang <dhdang@apm.com> - 2015-08-08 04:50 +0200
        [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA Duc Dang <dhdang@apm.com> - 2015-08-08 05:20 +0200
          [PATCH v5 2/2] usb: Add support for ACPI identification to xhci-platform Duc Dang <dhdang@apm.com> - 2015-08-08 05:20 +0200
          Re: [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32  bit DMA Russell King - ARM Linux <linux@arm.linux.org.uk> - 2015-08-08 11:30 +0200
            Re: [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32  bit DMA Duc Dang <dhdang@apm.com> - 2015-08-08 22:40 +0200
              Re: [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA Arnd Bergmann <arnd@arndb.de> - 2015-08-15 22:10 +0200
            [PATCH v6 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA Duc Dang <dhdang@apm.com> - 2015-08-10 09:40 +0200
              [PATCH v6 2/2] usb: Add support for ACPI identification to xhci-platform Duc Dang <dhdang@apm.com> - 2015-08-10 09:40 +0200
      Re: [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform Javier Martinez Canillas <javier@dowhile0.org> - 2015-08-08 07:50 +0200
        Re: [PATCH v4 2/2] usb: Add support for ACPI identification to  xhci-platform Greg KH <gregkh@linuxfoundation.org> - 2015-08-08 17:40 +0200
          Re: [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform Duc Dang <dhdang@apm.com> - 2015-08-08 18:50 +0200
          Re: [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform Javier Martinez Canillas <javier@dowhile0.org> - 2015-08-08 23:10 +0200

#1203123 — [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform

Provide the methods to let ACPI identify the need to use
xhci-platform. Change the Kconfig files so the
xhci-plat.o file is selectable during kernel config.

This has been tested on an ARM64 machine with platform XHCI, an
x86_64 machine with XHCI, and an x86_64 machine without XHCI.
There were no regressions or error messages on the machines
without platform XHCI.

[dhdang: regenerate the patch over 4.2-rc5]
Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
Signed-off-by: Duc Dang <dhdang@apm.com>

---
Changes from v3:
	Regenerate the patch over 4.2-rc5
	No code change

Changes from v2
	Replaced tristate with a boolean as the driver doesn't
		compile as a module
	Correct --help-- to ---help---

Changes from v1
	Renamed from "add support for APM X-Gene to xhci-platform"
	Removed changes to arm64/Kconfig
	Made CONFIG_USB_XHCI_PLATFORM a user selectable config option

 drivers/usb/host/Kconfig     |  7 ++++++-
 drivers/usb/host/xhci-plat.c | 11 +++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 8afc3c1..96231ee 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -32,7 +32,12 @@ config USB_XHCI_PCI
        default y
 
 config USB_XHCI_PLATFORM
-	tristate
+	tristate "xHCI platform driver support"
+	---help---
+	  Say 'Y' to enable the support for the xHCI host controller
+	  as a platform device. Many ARM SoCs provide USB this way.
+
+	  If unsure, say 'Y'.
 
 config USB_XHCI_MVEBU
 	tristate "xHCI support for Marvell Armada 375/38x"
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 5d03f8b..14b40d2 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -19,6 +19,7 @@
 #include <linux/usb/phy.h>
 #include <linux/slab.h>
 #include <linux/usb/xhci_pdriver.h>
+#include <linux/acpi.h>
 
 #include "xhci.h"
 #include "xhci-mvebu.h"
@@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
 MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
 #endif
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id usb_xhci_acpi_match[] = {
+	/* APM X-Gene USB Controller */
+	{ "PNP0D10", },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, usb_xhci_acpi_match);
+#endif
+
 static struct platform_driver usb_xhci_driver = {
 	.probe	= xhci_plat_probe,
 	.remove	= xhci_plat_remove,
@@ -269,6 +279,7 @@ static struct platform_driver usb_xhci_driver = {
 		.name = "xhci-hcd",
 		.pm = DEV_PM_OPS,
 		.of_match_table = of_match_ptr(usb_xhci_of_match),
+		.acpi_match_table = ACPI_PTR(usb_xhci_acpi_match),
 	},
 };
 MODULE_ALIAS("platform:xhci-hcd");
-- 
1.9.1

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#1203137 — Re: [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform

On Fri, Aug 07, 2015 at 06:03:36PM -0700, Duc Dang wrote:
> Provide the methods to let ACPI identify the need to use
> xhci-platform. Change the Kconfig files so the
> xhci-plat.o file is selectable during kernel config.
> 
> This has been tested on an ARM64 machine with platform XHCI, an
> x86_64 machine with XHCI, and an x86_64 machine without XHCI.
> There were no regressions or error messages on the machines
> without platform XHCI.
> 
> [dhdang: regenerate the patch over 4.2-rc5]
> Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
> Signed-off-by: Duc Dang <dhdang@apm.com>
> 
> ---
> Changes from v3:
> 	Regenerate the patch over 4.2-rc5
> 	No code change
> 
> Changes from v2
> 	Replaced tristate with a boolean as the driver doesn't
> 		compile as a module
> 	Correct --help-- to ---help---
> 
> Changes from v1
> 	Renamed from "add support for APM X-Gene to xhci-platform"
> 	Removed changes to arm64/Kconfig
> 	Made CONFIG_USB_XHCI_PLATFORM a user selectable config option
> 
>  drivers/usb/host/Kconfig     |  7 ++++++-
>  drivers/usb/host/xhci-plat.c | 11 +++++++++++
>  2 files changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
> index 8afc3c1..96231ee 100644
> --- a/drivers/usb/host/Kconfig
> +++ b/drivers/usb/host/Kconfig
> @@ -32,7 +32,12 @@ config USB_XHCI_PCI
>         default y
>  
>  config USB_XHCI_PLATFORM
> -	tristate
> +	tristate "xHCI platform driver support"
> +	---help---
> +	  Say 'Y' to enable the support for the xHCI host controller
> +	  as a platform device. Many ARM SoCs provide USB this way.
> +
> +	  If unsure, say 'Y'.
>  
>  config USB_XHCI_MVEBU
>  	tristate "xHCI support for Marvell Armada 375/38x"
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index 5d03f8b..14b40d2 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -19,6 +19,7 @@
>  #include <linux/usb/phy.h>
>  #include <linux/slab.h>
>  #include <linux/usb/xhci_pdriver.h>
> +#include <linux/acpi.h>
>  
>  #include "xhci.h"
>  #include "xhci-mvebu.h"
> @@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
>  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
>  #endif
>  
> +#ifdef CONFIG_ACPI

You shoudn't need this #ifdef, right?

thanks,

greg k-h
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#1203151

On Fri, Aug 7, 2015 at 6:29 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Fri, Aug 07, 2015 at 06:03:36PM -0700, Duc Dang wrote:
>> Provide the methods to let ACPI identify the need to use
>> xhci-platform. Change the Kconfig files so the
>> xhci-plat.o file is selectable during kernel config.
>>
>> This has been tested on an ARM64 machine with platform XHCI, an
>> x86_64 machine with XHCI, and an x86_64 machine without XHCI.
>> There were no regressions or error messages on the machines
>> without platform XHCI.
>>
>> [dhdang: regenerate the patch over 4.2-rc5]
>> Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
>> Signed-off-by: Duc Dang <dhdang@apm.com>
>>
>> ---
>> Changes from v3:
>>       Regenerate the patch over 4.2-rc5
>>       No code change
>>
>> Changes from v2
>>       Replaced tristate with a boolean as the driver doesn't
>>               compile as a module
>>       Correct --help-- to ---help---
>>
>> Changes from v1
>>       Renamed from "add support for APM X-Gene to xhci-platform"
>>       Removed changes to arm64/Kconfig
>>       Made CONFIG_USB_XHCI_PLATFORM a user selectable config option
>>
>>  drivers/usb/host/Kconfig     |  7 ++++++-
>>  drivers/usb/host/xhci-plat.c | 11 +++++++++++
>>  2 files changed, 17 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
>> index 8afc3c1..96231ee 100644
>> --- a/drivers/usb/host/Kconfig
>> +++ b/drivers/usb/host/Kconfig
>> @@ -32,7 +32,12 @@ config USB_XHCI_PCI
>>         default y
>>
>>  config USB_XHCI_PLATFORM
>> -     tristate
>> +     tristate "xHCI platform driver support"
>> +     ---help---
>> +       Say 'Y' to enable the support for the xHCI host controller
>> +       as a platform device. Many ARM SoCs provide USB this way.
>> +
>> +       If unsure, say 'Y'.
>>
>>  config USB_XHCI_MVEBU
>>       tristate "xHCI support for Marvell Armada 375/38x"
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index 5d03f8b..14b40d2 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>> @@ -19,6 +19,7 @@
>>  #include <linux/usb/phy.h>
>>  #include <linux/slab.h>
>>  #include <linux/usb/xhci_pdriver.h>
>> +#include <linux/acpi.h>
>>
>>  #include "xhci.h"
>>  #include "xhci-mvebu.h"
>> @@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
>>  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
>>  #endif
>>
>> +#ifdef CONFIG_ACPI
>
> You shoudn't need this #ifdef, right?

You are correct, Greg.

I will post a new version that remove this #ifdef CONFIG_ACPI shortly

>
> thanks,
>
> greg k-h



-- 
Regards,
Duc Dang.
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#1203153 — [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA

The xhci platform driver needs to work on systems that
either only support 64-bit DMA or only support 32-bit DMA.
Attempt to set a coherent dma mask for 64-bit DMA, and
attempt again with 32-bit DMA if that fails.

[dhdang: Regenerate the patch over 4.2-rc5]
Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Duc Dang <dhdang@apm.com>

---
Changes from v4:
	None

Changes from v3:
        Re-generate the patch over 4.2-rc5
        No code change.

Changes from v2:
        None

Changes from v1:
        Consolidated to use dma_set_mask_and_coherent
        Got rid of the check against sizeof(dma_addr_t)

 drivers/usb/host/xhci-plat.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 890ad9d..5d03f8b 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -93,14 +93,14 @@ static int xhci_plat_probe(struct platform_device *pdev)
 	if (irq < 0)
 		return -ENODEV;
 
-	/* Initialize dma_mask and coherent_dma_mask to 32-bits */
-	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
-	if (ret)
-		return ret;
-	if (!pdev->dev.dma_mask)
-		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
-	else
-		dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
+	/* Try setting the coherent_dma_mask to 64 bits, then try 32 bits */
+	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (ret) {
+		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+		if (ret)
+			return ret;
+	}
+
 
 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 	if (!hcd)
-- 
1.9.1

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#1203155 — [PATCH v5 2/2] usb: Add support for ACPI identification to xhci-platform

Provide the methods to let ACPI identify the need to use
xhci-platform. Change the Kconfig files so the
xhci-plat.o file is selectable during kernel config.

This has been tested on an ARM64 machine with platform XHCI, an
x86_64 machine with XHCI, and an x86_64 machine without XHCI.
There were no regressions or error messages on the machines
without platform XHCI.

Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
Signed-off-by: Duc Dang <dhdang@apm.com>

---
Changes from v4:
	Remove #ifdef CONFIG_ACPI

Changes from v3:
        Regenerate the patch over 4.2-rc5
        No code change

Changes from v2
        Replaced tristate with a boolean as the driver doesn't
                compile as a module
        Correct --help-- to ---help---

Changes from v1
        Renamed from "add support for APM X-Gene to xhci-platform"
        Removed changes to arm64/Kconfig
        Made CONFIG_USB_XHCI_PLATFORM a user selectable config option

 drivers/usb/host/Kconfig     | 7 ++++++-
 drivers/usb/host/xhci-plat.c | 9 +++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 8afc3c1..96231ee 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -32,7 +32,12 @@ config USB_XHCI_PCI
        default y
 
 config USB_XHCI_PLATFORM
-	tristate
+	tristate "xHCI platform driver support"
+	---help---
+	  Say 'Y' to enable the support for the xHCI host controller
+	  as a platform device. Many ARM SoCs provide USB this way.
+
+	  If unsure, say 'Y'.
 
 config USB_XHCI_MVEBU
 	tristate "xHCI support for Marvell Armada 375/38x"
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 5d03f8b..bd282cd 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -19,6 +19,7 @@
 #include <linux/usb/phy.h>
 #include <linux/slab.h>
 #include <linux/usb/xhci_pdriver.h>
+#include <linux/acpi.h>
 
 #include "xhci.h"
 #include "xhci-mvebu.h"
@@ -262,6 +263,13 @@ static const struct of_device_id usb_xhci_of_match[] = {
 MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
 #endif
 
+static const struct acpi_device_id usb_xhci_acpi_match[] = {
+	/* APM X-Gene USB Controller */
+	{ "PNP0D10", },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, usb_xhci_acpi_match);
+
 static struct platform_driver usb_xhci_driver = {
 	.probe	= xhci_plat_probe,
 	.remove	= xhci_plat_remove,
@@ -269,6 +277,7 @@ static struct platform_driver usb_xhci_driver = {
 		.name = "xhci-hcd",
 		.pm = DEV_PM_OPS,
 		.of_match_table = of_match_ptr(usb_xhci_of_match),
+		.acpi_match_table = ACPI_PTR(usb_xhci_acpi_match),
 	},
 };
 MODULE_ALIAS("platform:xhci-hcd");
-- 
1.9.1

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#1203234 — Re: [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA

On Fri, Aug 07, 2015 at 08:18:48PM -0700, Duc Dang wrote:
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index 890ad9d..5d03f8b 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -93,14 +93,14 @@ static int xhci_plat_probe(struct platform_device *pdev)
>  	if (irq < 0)
>  		return -ENODEV;
>  
> -	/* Initialize dma_mask and coherent_dma_mask to 32-bits */
> -	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
> -	if (ret)
> -		return ret;
> -	if (!pdev->dev.dma_mask)
> -		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
> -	else
> -		dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
> +	/* Try setting the coherent_dma_mask to 64 bits, then try 32 bits */
> +	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> +	if (ret) {
> +		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> +		if (ret)
> +			return ret;
> +	}

Note that dma_set_mask_and_coherent() and the original code are not
equivalent because of this:

	if (!pdev->dev.dma_mask)
		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;

If we know that pdev->dev.dma_mask will always be initialised at this
point, then the above change is fine.  If not, it's introducing a
regression - dma_set_mask_and_coherent() will fail if pdev->dev.dma_mask
is NULL (depending on the architectures implementation of dma_set_mask()).

Prefixing the above change with the two lines I mention above would
ensure equivalent behaviour.  Even if we do want to get rid of this,
I'd advise to do it as a separate patch after this change, which can
be independently reverted if there's problems with its removal.

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#1203364 — Re: [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA

On Sat, Aug 8, 2015 at 2:22 AM, Russell King - ARM Linux
<linux@arm.linux.org.uk> wrote:
> On Fri, Aug 07, 2015 at 08:18:48PM -0700, Duc Dang wrote:
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index 890ad9d..5d03f8b 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>> @@ -93,14 +93,14 @@ static int xhci_plat_probe(struct platform_device *pdev)
>>       if (irq < 0)
>>               return -ENODEV;
>>
>> -     /* Initialize dma_mask and coherent_dma_mask to 32-bits */
>> -     ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
>> -     if (ret)
>> -             return ret;
>> -     if (!pdev->dev.dma_mask)
>> -             pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
>> -     else
>> -             dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
>> +     /* Try setting the coherent_dma_mask to 64 bits, then try 32 bits */
>> +     ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
>> +     if (ret) {
>> +             ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
>> +             if (ret)
>> +                     return ret;
>> +     }
>
> Note that dma_set_mask_and_coherent() and the original code are not
> equivalent because of this:
>
>         if (!pdev->dev.dma_mask)
>                 pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
>
> If we know that pdev->dev.dma_mask will always be initialised at this
> point, then the above change is fine.  If not, it's introducing a
> regression - dma_set_mask_and_coherent() will fail if pdev->dev.dma_mask
> is NULL (depending on the architectures implementation of dma_set_mask()).
>
> Prefixing the above change with the two lines I mention above would
> ensure equivalent behaviour.  Even if we do want to get rid of this,
> I'd advise to do it as a separate patch after this change, which can
> be independently reverted if there's problems with its removal.
>
Hi Russell,

I will add the 2 lines you mentioned back to next version of the
patch. It is safer to do it that way as I do not see
pdev->dev.dma_mask gets initialized before the call
dma_set_mask_and_coherent  inside this xhci_plat.c file.

> --
> FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
> according to speedtest.net.

-- 
Regards,
Duc Dang.
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#1208151 — Re: [PATCH v5 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA

On Saturday 08 August 2015 13:31:02 Duc Dang wrote:
> >
> > If we know that pdev->dev.dma_mask will always be initialised at this
> > point, then the above change is fine.  If not, it's introducing a
> > regression - dma_set_mask_and_coherent() will fail if pdev->dev.dma_mask
> > is NULL (depending on the architectures implementation of dma_set_mask()).
> >
> > Prefixing the above change with the two lines I mention above would
> > ensure equivalent behaviour.  Even if we do want to get rid of this,
> > I'd advise to do it as a separate patch after this change, which can
> > be independently reverted if there's problems with its removal.
> >
> Hi Russell,
> 
> I will add the 2 lines you mentioned back to next version of the
> patch. It is safer to do it that way as I do not see
> pdev->dev.dma_mask gets initialized before the call
> dma_set_mask_and_coherent  inside this xhci_plat.c file.

It would be good to add a WARN_ON() to the case where dma_mask
is a NULL pointer at the least. That way, we will at least
find out if there are some broken platforms that do not correctly
initialize the mask pointer.

	Arnd
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#1203860 — [PATCH v6 1/2] usb: make xhci platform driver use 64 bit or 32 bit DMA

The xhci platform driver needs to work on systems that
either only support 64-bit DMA or only support 32-bit DMA.
Attempt to set a coherent dma mask for 64-bit DMA, and
attempt again with 32-bit DMA if that fails.

[dhdang: regenerate the patch over 4.2-rc5 and address new comments]
Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Duc Dang <dhdang@apm.com>

---
Changes from v5:
	-Change comment
	-Assign dma_mask to coherent_dma_mask if dma_mask is NULL
	to make sure dma_set_mask_and_coherent does not	fail prematurely.

Changes from v4:
        -None

Changes from v3:
        -Re-generate the patch over 4.2-rc5
        -No code change.

Changes from v2:
        -None

Changes from v1:
        -Consolidated to use dma_set_mask_and_coherent
        -Got rid of the check against sizeof(dma_addr_t)

 drivers/usb/host/xhci-plat.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 890ad9d..5d1b84b 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -93,14 +93,18 @@ static int xhci_plat_probe(struct platform_device *pdev)
 	if (irq < 0)
 		return -ENODEV;
 
-	/* Initialize dma_mask and coherent_dma_mask to 32-bits */
-	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
-	if (ret)
-		return ret;
+	/*
+	 * Try setting dma_mask and coherent_dma_mask to 64 bits,
+	 * then try 32 bits
+	 */
 	if (!pdev->dev.dma_mask)
 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
-	else
-		dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
+	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (ret) {
+		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+		if (ret)
+			return ret;
+	}
 
 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 	if (!hcd)
-- 
1.9.1

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#1203861 — [PATCH v6 2/2] usb: Add support for ACPI identification to xhci-platform

Provide the methods to let ACPI identify the need to use
xhci-platform. Change the Kconfig files so the
xhci-plat.o file is selectable during kernel config.

This has been tested on an ARM64 machine with platform XHCI, an
x86_64 machine with XHCI, and an x86_64 machine without XHCI.
There were no regressions or error messages on the machines
without platform XHCI.

[dhdang: regenerate the patch over 4.2-rc5 and address new comments]
Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
Signed-off-by: Duc Dang <dhdang@apm.com>

---
Change from v5:
	Change comment to "XHCI-compliant USB Controller" as
	"PNP0D10" ID is not X-Gene specific

Changes from v4:
        Remove #ifdef CONFIG_ACPI

Changes from v3:
        Regenerate the patch over 4.2-rc5
        No code change

Changes from v2
        Replaced tristate with a boolean as the driver doesn't
                compile as a module
        Correct --help-- to ---help---

Changes from v1
        Renamed from "add support for APM X-Gene to xhci-platform"
        Removed changes to arm64/Kconfig
        Made CONFIG_USB_XHCI_PLATFORM a user selectable config option

 drivers/usb/host/Kconfig     | 7 ++++++-
 drivers/usb/host/xhci-plat.c | 9 +++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 8afc3c1..96231ee 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -32,7 +32,12 @@ config USB_XHCI_PCI
        default y
 
 config USB_XHCI_PLATFORM
-	tristate
+	tristate "xHCI platform driver support"
+	---help---
+	  Say 'Y' to enable the support for the xHCI host controller
+	  as a platform device. Many ARM SoCs provide USB this way.
+
+	  If unsure, say 'Y'.
 
 config USB_XHCI_MVEBU
 	tristate "xHCI support for Marvell Armada 375/38x"
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 5d1b84b..7ec2d31 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -19,6 +19,7 @@
 #include <linux/usb/phy.h>
 #include <linux/slab.h>
 #include <linux/usb/xhci_pdriver.h>
+#include <linux/acpi.h>
 
 #include "xhci.h"
 #include "xhci-mvebu.h"
@@ -266,6 +267,13 @@ static const struct of_device_id usb_xhci_of_match[] = {
 MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
 #endif
 
+static const struct acpi_device_id usb_xhci_acpi_match[] = {
+	/* XHCI-compliant USB Controller */
+	{ "PNP0D10", },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, usb_xhci_acpi_match);
+
 static struct platform_driver usb_xhci_driver = {
 	.probe	= xhci_plat_probe,
 	.remove	= xhci_plat_remove,
@@ -273,6 +281,7 @@ static struct platform_driver usb_xhci_driver = {
 		.name = "xhci-hcd",
 		.pm = DEV_PM_OPS,
 		.of_match_table = of_match_ptr(usb_xhci_of_match),
+		.acpi_match_table = ACPI_PTR(usb_xhci_acpi_match),
 	},
 };
 MODULE_ALIAS("platform:xhci-hcd");
-- 
1.9.1

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#1203176

Hello Greg,

On Sat, Aug 8, 2015 at 3:29 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Fri, Aug 07, 2015 at 06:03:36PM -0700, Duc Dang wrote:
>> Provide the methods to let ACPI identify the need to use
>> xhci-platform. Change the Kconfig files so the
>> xhci-plat.o file is selectable during kernel config.
>>
>> This has been tested on an ARM64 machine with platform XHCI, an
>> x86_64 machine with XHCI, and an x86_64 machine without XHCI.
>> There were no regressions or error messages on the machines
>> without platform XHCI.
>>
>> [dhdang: regenerate the patch over 4.2-rc5]
>> Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
>> Signed-off-by: Duc Dang <dhdang@apm.com>
>>
>> ---
>> Changes from v3:
>>       Regenerate the patch over 4.2-rc5
>>       No code change
>>
>> Changes from v2
>>       Replaced tristate with a boolean as the driver doesn't
>>               compile as a module
>>       Correct --help-- to ---help---
>>
>> Changes from v1
>>       Renamed from "add support for APM X-Gene to xhci-platform"
>>       Removed changes to arm64/Kconfig
>>       Made CONFIG_USB_XHCI_PLATFORM a user selectable config option
>>
>>  drivers/usb/host/Kconfig     |  7 ++++++-
>>  drivers/usb/host/xhci-plat.c | 11 +++++++++++
>>  2 files changed, 17 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
>> index 8afc3c1..96231ee 100644
>> --- a/drivers/usb/host/Kconfig
>> +++ b/drivers/usb/host/Kconfig
>> @@ -32,7 +32,12 @@ config USB_XHCI_PCI
>>         default y
>>
>>  config USB_XHCI_PLATFORM
>> -     tristate
>> +     tristate "xHCI platform driver support"
>> +     ---help---
>> +       Say 'Y' to enable the support for the xHCI host controller
>> +       as a platform device. Many ARM SoCs provide USB this way.
>> +
>> +       If unsure, say 'Y'.
>>
>>  config USB_XHCI_MVEBU
>>       tristate "xHCI support for Marvell Armada 375/38x"
>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> index 5d03f8b..14b40d2 100644
>> --- a/drivers/usb/host/xhci-plat.c
>> +++ b/drivers/usb/host/xhci-plat.c
>> @@ -19,6 +19,7 @@
>>  #include <linux/usb/phy.h>
>>  #include <linux/slab.h>
>>  #include <linux/usb/xhci_pdriver.h>
>> +#include <linux/acpi.h>
>>
>>  #include "xhci.h"
>>  #include "xhci-mvebu.h"
>> @@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
>>  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
>>  #endif
>>
>> +#ifdef CONFIG_ACPI
>
> You shoudn't need this #ifdef, right?
>

Why it is not needed?

The driver does .acpi_match_table = ACPI_PTR(usb_xhci_acpi_match) and
ACPI_PTR() is NULL if CONFIG_ACPI is not enabled. Which can happen
AFAIU since the driver also supports OF. So without the #ifdef guards,
.acpi_match_table = NULL and the struct acpi_device_id
usb_xhci_acpi_match[] will be built but not used.

Or am I missing something?

> thanks,
>
> greg k-h
>

Best regards,
Javier
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#1203285 — Re: [PATCH v4 2/2] usb: Add support for ACPI identification to xhci-platform

On Sat, Aug 08, 2015 at 07:43:40AM +0200, Javier Martinez Canillas wrote:
> Hello Greg,
> 
> On Sat, Aug 8, 2015 at 3:29 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> > On Fri, Aug 07, 2015 at 06:03:36PM -0700, Duc Dang wrote:
> >> Provide the methods to let ACPI identify the need to use
> >> xhci-platform. Change the Kconfig files so the
> >> xhci-plat.o file is selectable during kernel config.
> >>
> >> This has been tested on an ARM64 machine with platform XHCI, an
> >> x86_64 machine with XHCI, and an x86_64 machine without XHCI.
> >> There were no regressions or error messages on the machines
> >> without platform XHCI.
> >>
> >> [dhdang: regenerate the patch over 4.2-rc5]
> >> Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
> >> Signed-off-by: Duc Dang <dhdang@apm.com>
> >>
> >> ---
> >> Changes from v3:
> >>       Regenerate the patch over 4.2-rc5
> >>       No code change
> >>
> >> Changes from v2
> >>       Replaced tristate with a boolean as the driver doesn't
> >>               compile as a module
> >>       Correct --help-- to ---help---
> >>
> >> Changes from v1
> >>       Renamed from "add support for APM X-Gene to xhci-platform"
> >>       Removed changes to arm64/Kconfig
> >>       Made CONFIG_USB_XHCI_PLATFORM a user selectable config option
> >>
> >>  drivers/usb/host/Kconfig     |  7 ++++++-
> >>  drivers/usb/host/xhci-plat.c | 11 +++++++++++
> >>  2 files changed, 17 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
> >> index 8afc3c1..96231ee 100644
> >> --- a/drivers/usb/host/Kconfig
> >> +++ b/drivers/usb/host/Kconfig
> >> @@ -32,7 +32,12 @@ config USB_XHCI_PCI
> >>         default y
> >>
> >>  config USB_XHCI_PLATFORM
> >> -     tristate
> >> +     tristate "xHCI platform driver support"
> >> +     ---help---
> >> +       Say 'Y' to enable the support for the xHCI host controller
> >> +       as a platform device. Many ARM SoCs provide USB this way.
> >> +
> >> +       If unsure, say 'Y'.
> >>
> >>  config USB_XHCI_MVEBU
> >>       tristate "xHCI support for Marvell Armada 375/38x"
> >> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> >> index 5d03f8b..14b40d2 100644
> >> --- a/drivers/usb/host/xhci-plat.c
> >> +++ b/drivers/usb/host/xhci-plat.c
> >> @@ -19,6 +19,7 @@
> >>  #include <linux/usb/phy.h>
> >>  #include <linux/slab.h>
> >>  #include <linux/usb/xhci_pdriver.h>
> >> +#include <linux/acpi.h>
> >>
> >>  #include "xhci.h"
> >>  #include "xhci-mvebu.h"
> >> @@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
> >>  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
> >>  #endif
> >>
> >> +#ifdef CONFIG_ACPI
> >
> > You shoudn't need this #ifdef, right?
> >
> 
> Why it is not needed?

Why is it needed?

> The driver does .acpi_match_table = ACPI_PTR(usb_xhci_acpi_match) and
> ACPI_PTR() is NULL if CONFIG_ACPI is not enabled. Which can happen
> AFAIU since the driver also supports OF. So without the #ifdef guards,
> .acpi_match_table = NULL and the struct acpi_device_id
> usb_xhci_acpi_match[] will be built but not used.

Which is just fine, right?

> Or am I missing something?

Don't put #ifdef in .c files if at all possible is the kernel style
rules.

thanks,

greg k-h
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#1203322

On Sat, Aug 8, 2015 at 8:37 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Sat, Aug 08, 2015 at 07:43:40AM +0200, Javier Martinez Canillas wrote:
>> Hello Greg,
>>
>> On Sat, Aug 8, 2015 at 3:29 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
>> > On Fri, Aug 07, 2015 at 06:03:36PM -0700, Duc Dang wrote:
>> >> Provide the methods to let ACPI identify the need to use
>> >> xhci-platform. Change the Kconfig files so the
>> >> xhci-plat.o file is selectable during kernel config.
>> >>
>> >> This has been tested on an ARM64 machine with platform XHCI, an
>> >> x86_64 machine with XHCI, and an x86_64 machine without XHCI.
>> >> There were no regressions or error messages on the machines
>> >> without platform XHCI.
>> >>
>> >> [dhdang: regenerate the patch over 4.2-rc5]
>> >> Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
>> >> Signed-off-by: Duc Dang <dhdang@apm.com>
>> >>
>> >> ---
>> >> Changes from v3:
>> >>       Regenerate the patch over 4.2-rc5
>> >>       No code change
>> >>
>> >> Changes from v2
>> >>       Replaced tristate with a boolean as the driver doesn't
>> >>               compile as a module
>> >>       Correct --help-- to ---help---
>> >>
>> >> Changes from v1
>> >>       Renamed from "add support for APM X-Gene to xhci-platform"
>> >>       Removed changes to arm64/Kconfig
>> >>       Made CONFIG_USB_XHCI_PLATFORM a user selectable config option
>> >>
>> >>  drivers/usb/host/Kconfig     |  7 ++++++-
>> >>  drivers/usb/host/xhci-plat.c | 11 +++++++++++
>> >>  2 files changed, 17 insertions(+), 1 deletion(-)
>> >>
>> >> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
>> >> index 8afc3c1..96231ee 100644
>> >> --- a/drivers/usb/host/Kconfig
>> >> +++ b/drivers/usb/host/Kconfig
>> >> @@ -32,7 +32,12 @@ config USB_XHCI_PCI
>> >>         default y
>> >>
>> >>  config USB_XHCI_PLATFORM
>> >> -     tristate
>> >> +     tristate "xHCI platform driver support"
>> >> +     ---help---
>> >> +       Say 'Y' to enable the support for the xHCI host controller
>> >> +       as a platform device. Many ARM SoCs provide USB this way.
>> >> +
>> >> +       If unsure, say 'Y'.
>> >>
>> >>  config USB_XHCI_MVEBU
>> >>       tristate "xHCI support for Marvell Armada 375/38x"
>> >> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> >> index 5d03f8b..14b40d2 100644
>> >> --- a/drivers/usb/host/xhci-plat.c
>> >> +++ b/drivers/usb/host/xhci-plat.c
>> >> @@ -19,6 +19,7 @@
>> >>  #include <linux/usb/phy.h>
>> >>  #include <linux/slab.h>
>> >>  #include <linux/usb/xhci_pdriver.h>
>> >> +#include <linux/acpi.h>
>> >>
>> >>  #include "xhci.h"
>> >>  #include "xhci-mvebu.h"
>> >> @@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
>> >>  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
>> >>  #endif
>> >>
>> >> +#ifdef CONFIG_ACPI
>> >
>> > You shoudn't need this #ifdef, right?
>> >
>>
>> Why it is not needed?
>
> Why is it needed?
>
>> The driver does .acpi_match_table = ACPI_PTR(usb_xhci_acpi_match) and
>> ACPI_PTR() is NULL if CONFIG_ACPI is not enabled. Which can happen
>> AFAIU since the driver also supports OF. So without the #ifdef guards,
>> .acpi_match_table = NULL and the struct acpi_device_id
>> usb_xhci_acpi_match[] will be built but not used.
>
> Which is just fine, right?
>
>> Or am I missing something?
>
> Don't put #ifdef in .c files if at all possible is the kernel style
> rules.

I tested booting with both device tree and ACPI with the new code that
has #ifdef CONFIG_ACPI removed and USB works fine with my X-Gene Arm64
platform.

>
> thanks,
>
> greg k-h



-- 
Regards,
Duc Dang.
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#1203373

Hello Greg,

On Sat, Aug 8, 2015 at 5:37 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Sat, Aug 08, 2015 at 07:43:40AM +0200, Javier Martinez Canillas wrote:
>> Hello Greg,
>>
>> On Sat, Aug 8, 2015 at 3:29 AM, Greg KH <gregkh@linuxfoundation.org> wrote:
>> > On Fri, Aug 07, 2015 at 06:03:36PM -0700, Duc Dang wrote:
>> >> Provide the methods to let ACPI identify the need to use
>> >> xhci-platform. Change the Kconfig files so the
>> >> xhci-plat.o file is selectable during kernel config.
>> >>
>> >> This has been tested on an ARM64 machine with platform XHCI, an
>> >> x86_64 machine with XHCI, and an x86_64 machine without XHCI.
>> >> There were no regressions or error messages on the machines
>> >> without platform XHCI.
>> >>
>> >> [dhdang: regenerate the patch over 4.2-rc5]
>> >> Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>
>> >> Signed-off-by: Duc Dang <dhdang@apm.com>
>> >>
>> >> ---
>> >> Changes from v3:
>> >>       Regenerate the patch over 4.2-rc5
>> >>       No code change
>> >>
>> >> Changes from v2
>> >>       Replaced tristate with a boolean as the driver doesn't
>> >>               compile as a module
>> >>       Correct --help-- to ---help---
>> >>
>> >> Changes from v1
>> >>       Renamed from "add support for APM X-Gene to xhci-platform"
>> >>       Removed changes to arm64/Kconfig
>> >>       Made CONFIG_USB_XHCI_PLATFORM a user selectable config option
>> >>
>> >>  drivers/usb/host/Kconfig     |  7 ++++++-
>> >>  drivers/usb/host/xhci-plat.c | 11 +++++++++++
>> >>  2 files changed, 17 insertions(+), 1 deletion(-)
>> >>
>> >> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
>> >> index 8afc3c1..96231ee 100644
>> >> --- a/drivers/usb/host/Kconfig
>> >> +++ b/drivers/usb/host/Kconfig
>> >> @@ -32,7 +32,12 @@ config USB_XHCI_PCI
>> >>         default y
>> >>
>> >>  config USB_XHCI_PLATFORM
>> >> -     tristate
>> >> +     tristate "xHCI platform driver support"
>> >> +     ---help---
>> >> +       Say 'Y' to enable the support for the xHCI host controller
>> >> +       as a platform device. Many ARM SoCs provide USB this way.
>> >> +
>> >> +       If unsure, say 'Y'.
>> >>
>> >>  config USB_XHCI_MVEBU
>> >>       tristate "xHCI support for Marvell Armada 375/38x"
>> >> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
>> >> index 5d03f8b..14b40d2 100644
>> >> --- a/drivers/usb/host/xhci-plat.c
>> >> +++ b/drivers/usb/host/xhci-plat.c
>> >> @@ -19,6 +19,7 @@
>> >>  #include <linux/usb/phy.h>
>> >>  #include <linux/slab.h>
>> >>  #include <linux/usb/xhci_pdriver.h>
>> >> +#include <linux/acpi.h>
>> >>
>> >>  #include "xhci.h"
>> >>  #include "xhci-mvebu.h"
>> >> @@ -262,6 +263,15 @@ static const struct of_device_id usb_xhci_of_match[] = {
>> >>  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
>> >>  #endif
>> >>
>> >> +#ifdef CONFIG_ACPI
>> >
>> > You shoudn't need this #ifdef, right?
>> >
>>
>> Why it is not needed?
>
> Why is it needed?
>

As explained, to have avoid having an unused variable.

>> The driver does .acpi_match_table = ACPI_PTR(usb_xhci_acpi_match) and
>> ACPI_PTR() is NULL if CONFIG_ACPI is not enabled. Which can happen
>> AFAIU since the driver also supports OF. So without the #ifdef guards,
>> .acpi_match_table = NULL and the struct acpi_device_id
>> usb_xhci_acpi_match[] will be built but not used.
>
> Which is just fine, right?
>

I've seen people having different opinions about this specific case
(using #ifdef guards for ACPI, OF, etc match tables definition),
that's why I asked.

>> Or am I missing something?
>
> Don't put #ifdef in .c files if at all possible is the kernel style
> rules.
>

I know but as you said the rule is to not have #ifdef if possible. But
I understand now that for you this case doesn't justify the #ifdefery.

> thanks,
>
> greg k-h

Best regards,
Javier
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