[v1,2/9] usb: chipidea: udc: Support SKB alignment quirk

Message ID 719de7513f42948f5f75742c31f4cc09582411fd.1499273075.git.digetx@gmail.com
State Superseded
Headers show

Commit Message

Dmitry Osipenko July 5, 2017, 5:19 p.m.
NVIDIA Tegra20 UDC can't cope with unaligned DMA and require a USB gadget
quirk that avoids SKB buffer alignment to be set in order to make Ethernet
Gadget working. Later Tegra generations do not require that quirk. Let's
add a new platform data flag that allows to enable USB gadget quirk for
platforms that require it.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/usb/chipidea/udc.c   | 3 +++
 include/linux/usb/chipidea.h | 1 +
 2 files changed, 4 insertions(+)

Comments

Peter Chen July 6, 2017, 1:13 a.m. | #1
On Wed, Jul 05, 2017 at 08:19:51PM +0300, Dmitry Osipenko wrote:
> NVIDIA Tegra20 UDC can't cope with unaligned DMA and require a USB gadget
> quirk that avoids SKB buffer alignment to be set in order to make Ethernet
> Gadget working. Later Tegra generations do not require that quirk. Let's
> add a new platform data flag that allows to enable USB gadget quirk for
> platforms that require it.
> 
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>  drivers/usb/chipidea/udc.c   | 3 +++
>  include/linux/usb/chipidea.h | 1 +
>  2 files changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> index d68b125796f9..404f10513339 100644
> --- a/drivers/usb/chipidea/udc.c
> +++ b/drivers/usb/chipidea/udc.c
> @@ -1899,6 +1899,9 @@ static int udc_start(struct ci_hdrc *ci)
>  	ci->gadget.name         = ci->platdata->name;
>  	ci->gadget.otg_caps	= otg_caps;
>  
> +	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA)
> +		ci->gadget.quirk_avoids_skb_reserve = 1;
> +
>  	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
>  						otg_caps->adp_support))
>  		ci->gadget.is_otg = 1;
> diff --git a/include/linux/usb/chipidea.h b/include/linux/usb/chipidea.h
> index c5fdfcf99828..d725cff7268d 100644
> --- a/include/linux/usb/chipidea.h
> +++ b/include/linux/usb/chipidea.h
> @@ -58,6 +58,7 @@ struct ci_hdrc_platform_data {
>  #define CI_HDRC_OVERRIDE_TX_BURST	BIT(10)
>  #define CI_HDRC_OVERRIDE_RX_BURST	BIT(11)
>  #define CI_HDRC_OVERRIDE_PHY_CONTROL	BIT(12) /* Glue layer manages phy */
> +#define CI_HDRC_REQUIRES_ALIGNED_DMA	BIT(13)
>  	enum usb_dr_mode	dr_mode;
>  #define CI_HDRC_CONTROLLER_RESET_EVENT		0
>  #define CI_HDRC_CONTROLLER_STOPPED_EVENT	1

Acked-by: Peter Chen <peter.chen@nxp.com>

Patch

diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index d68b125796f9..404f10513339 100644
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -1899,6 +1899,9 @@  static int udc_start(struct ci_hdrc *ci)
 	ci->gadget.name         = ci->platdata->name;
 	ci->gadget.otg_caps	= otg_caps;
 
+	if (ci->platdata->flags & CI_HDRC_REQUIRES_ALIGNED_DMA)
+		ci->gadget.quirk_avoids_skb_reserve = 1;
+
 	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
 						otg_caps->adp_support))
 		ci->gadget.is_otg = 1;
diff --git a/include/linux/usb/chipidea.h b/include/linux/usb/chipidea.h
index c5fdfcf99828..d725cff7268d 100644
--- a/include/linux/usb/chipidea.h
+++ b/include/linux/usb/chipidea.h
@@ -58,6 +58,7 @@  struct ci_hdrc_platform_data {
 #define CI_HDRC_OVERRIDE_TX_BURST	BIT(10)
 #define CI_HDRC_OVERRIDE_RX_BURST	BIT(11)
 #define CI_HDRC_OVERRIDE_PHY_CONTROL	BIT(12) /* Glue layer manages phy */
+#define CI_HDRC_REQUIRES_ALIGNED_DMA	BIT(13)
 	enum usb_dr_mode	dr_mode;
 #define CI_HDRC_CONTROLLER_RESET_EVENT		0
 #define CI_HDRC_CONTROLLER_STOPPED_EVENT	1