Re: [RFC][PATCH v2 08/13] usb: otg: hub: Notify OTG fsm when A device sets b_hnp_enable

From: Peter Chen
Date: Thu Apr 16 2015 - 22:31:13 EST


On Tue, Apr 14, 2015 at 01:41:55PM +0300, Roger Quadros wrote:
> This is the a_set_b_hnp_enable flag in the OTG state machine
> diagram and must be set when the A-Host has successfully set
> the b_hnp_enable feature of the OTG-B-Peripheral attached to it.
>
> When this bit changes we kick our OTG FSM to make note of the
> change and act accordingly.
>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
> drivers/usb/core/hub.c | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index d7c3d5a..ab0d498 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -22,6 +22,7 @@
> #include <linux/usb/hcd.h>
> #include <linux/usb/otg.h>
> #include <linux/usb/quirks.h>
> +#include <linux/usb/usb-otg.h>
> #include <linux/workqueue.h>
> #include <linux/mutex.h>
> #include <linux/random.h>
> @@ -2270,6 +2271,9 @@ static int usb_enumerate_device_otg(struct usb_device *udev)
> "can't set HNP mode: %d\n",
> err);
> bus->b_hnp_enable = 0;
> + } else {
> + /* notify OTG fsm about a_set_b_hnp_enable */
> + usb_otg_kick_fsm(udev->bus->controller);
> }
> }
> }
> @@ -4244,8 +4248,13 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
> */
> if (!hdev->parent) {
> delay = HUB_ROOT_RESET_TIME;
> - if (port1 == hdev->bus->otg_port)
> + if (port1 == hdev->bus->otg_port) {
> hdev->bus->b_hnp_enable = 0;
> +#ifdef CONFIG_USB_OTG
> + /* notify OTG fsm about a_set_b_hnp_enable change */
> + usb_otg_kick_fsm(hdev->bus->controller);
> +#endif
> + }
> }
>
> /* Some low speed devices have problems with the quick delay, so */
> --
> 2.1.0
>

Since the fsm has already kicked, the only thing we need is update
fsm.a_set_b_hnp_enable, but this flag is missing at current fsm
structure.

--

Best Regards,
Peter Chen
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