Commit ca8b0332 authored by Chen Yu's avatar Chen Yu Committed by Felipe Balbi
Browse files

usb: dwc2: Add a quirk to allow speed negotiation for Hisilicon Hi6220 



The Hi6220's usb controller is limited in that it does not
support "Split Transactions", so it does not support communicating
with low-speed and full-speed devices behind a high-speed hub.

Thus it requires a quirk so that we can manually drop the usb
speed when low/full-speed are attached, and bump back to high
speed when they are removed.

Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Guodong Xu <guodong.xu@linaro.org>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: John Youn <johnyoun@synopsys.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Chen Yu <chenyu56@huawei.com>
Cc: Vardan Mikayelyan <mvardan@synopsys.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: default avatarChen Yu <chenyu56@huawei.com>
[jstultz: Reworked to simplify the patch, and made
 commit log to be more specific about the issue]
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarJohn Youn <johnyoun@synopsys.com>
Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
parent 9156a7ef

drivers/usb/dwc2/core.h

+7 −0
Original line number Diff line number Diff line
@@ -444,6 +444,11 @@ enum dwc2_ep0_state { 
 *			in DWORDS with possible values from from

 *			16-32768 (default: 256, 256, 256, 256, 768,

 *			768, 768, 768, 0, 0, 0, 0, 0, 0, 0).

 * @change_speed_quirk: Change speed configuration to DWC2_SPEED_PARAM_FULL

 *                      while full&low speed device connect. And change speed

 *                      back to DWC2_SPEED_PARAM_HIGH while device is gone.

 *			0 - No (default)

 *			1 - Yes

 *

 * The following parameters may be specified when starting the module. These

 * parameters define how the DWC_otg controller should be configured. A
@@ -501,6 +506,8 @@ struct dwc2_core_params { 
	u32 g_rx_fifo_size;

	u32 g_np_tx_fifo_size;

	u32 g_tx_fifo_size[MAX_EPS_CHANNELS];



	bool change_speed_quirk;

};



/**

drivers/usb/dwc2/hcd.c

+60 −0
Original line number Diff line number Diff line
@@ -4868,6 +4868,61 @@ static void _dwc2_hcd_clear_tt_buffer_complete(struct usb_hcd *hcd, 
	spin_unlock_irqrestore(&hsotg->lock, flags);

}



/*

 * HPRT0_SPD_HIGH_SPEED: high speed

 * HPRT0_SPD_FULL_SPEED: full speed

 */

static void dwc2_change_bus_speed(struct usb_hcd *hcd, int speed)

{

	struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);



	if (hsotg->params.speed == speed)

		return;



	hsotg->params.speed = speed;

	queue_work(hsotg->wq_otg, &hsotg->wf_otg);

}



static void dwc2_free_dev(struct usb_hcd *hcd, struct usb_device *udev)

{

	struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);



	if (!hsotg->params.change_speed_quirk)

		return;



	/*

	 * On removal, set speed to default high-speed.

	 */

	if (udev->parent && udev->parent->speed > USB_SPEED_UNKNOWN &&

	    udev->parent->speed < USB_SPEED_HIGH) {

		dev_info(hsotg->dev, "Set speed to default high-speed\n");

		dwc2_change_bus_speed(hcd, HPRT0_SPD_HIGH_SPEED);

	}

}



static int dwc2_reset_device(struct usb_hcd *hcd, struct usb_device *udev)

{

	struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);



	if (!hsotg->params.change_speed_quirk)

		return 0;



	if (udev->speed == USB_SPEED_HIGH) {

		dev_info(hsotg->dev, "Set speed to high-speed\n");

		dwc2_change_bus_speed(hcd, HPRT0_SPD_HIGH_SPEED);

	} else if ((udev->speed == USB_SPEED_FULL ||

				udev->speed == USB_SPEED_LOW)) {

		/*

		 * Change speed setting to full-speed if there's

		 * a full-speed or low-speed device plugged in.

		 */

		dev_info(hsotg->dev, "Set speed to full-speed\n");

		dwc2_change_bus_speed(hcd, HPRT0_SPD_FULL_SPEED);

	}



	return 0;

}



static struct hc_driver dwc2_hc_driver = {

	.description = "dwc2_hsotg",

	.product_desc = "DWC OTG Controller",
@@ -5023,6 +5078,11 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq) 
			dev_warn(hsotg->dev, "can't set coherent DMA mask\n");

	}



	if (hsotg->params.change_speed_quirk) {

		dwc2_hc_driver.free_dev = dwc2_free_dev;

		dwc2_hc_driver.reset_device = dwc2_reset_device;

	}



	hcd = usb_create_hcd(&dwc2_hc_driver, hsotg->dev, dev_name(hsotg->dev));

	if (!hcd)

		goto error1;

drivers/usb/dwc2/params.c

+1 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ static void dwc2_set_his_params(struct dwc2_hsotg *hsotg) 
	p->ahbcfg = GAHBCFG_HBSTLEN_INCR16 <<

		GAHBCFG_HBSTLEN_SHIFT;

	p->uframe_sched = false;

	p->change_speed_quirk = true;

}



static void dwc2_set_rk_params(struct dwc2_hsotg *hsotg)

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