lkml.org 
[lkml]   [2016]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC][PATCH 2/2] usb: dwc2: Add a quirk to allow speed negotiation for Hisilicon Hi6220
Date
From: Chen Yu <chenyu56@huawei.com>

The Hi6220's usb controller is limited in that it does not
automatically autonegotiate the usb speed. Thus it requires a
quirk so that we can manually negotiate the best usb speed for
the attached device.

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: Mark Rutland <mark.rutland@arm.com>
Cc: John Youn <johnyoun@synopsys.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Chen Yu <chenyu56@huawei.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
arch/arm64/boot/dts/hisilicon/hi6220.dtsi | 1 +
drivers/usb/dwc2/core.h | 7 +++
drivers/usb/dwc2/hcd.c | 75 +++++++++++++++++++++++++++++++
drivers/usb/dwc2/platform.c | 3 ++
4 files changed, 86 insertions(+)

diff --git a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
index 17839db..2c8f435 100644
--- a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
+++ b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
@@ -752,6 +752,7 @@
g-np-tx-fifo-size = <128>;
g-tx-fifo-size = <128 128 128 128 128 128>;
interrupts = <0 77 0x4>;
+ hi6220,change_speed_quirk;
};

mailbox: mailbox@f7510000 {
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 2a21a04..24fea73 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -823,6 +823,10 @@ struct dwc2_hregs_backup {
* @frame_list_sz: Frame list size
* @desc_gen_cache: Kmem cache for generic descriptors
* @desc_hsisoc_cache: Kmem cache for hs isochronous descriptors
+ * @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.
+ * @device_count: Number of devices connect to root hub
*
* These are for peripheral mode:
*
@@ -951,6 +955,9 @@ struct dwc2_hsotg {
struct kmem_cache *desc_gen_cache;
struct kmem_cache *desc_hsisoc_cache;

+ int change_speed_quirk;
+ unsigned int device_count;
+
#ifdef DEBUG
u32 frrem_samples;
u64 frrem_accum;
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index b374e60..663033e 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -4868,6 +4868,75 @@ 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->core_params->speed == speed)
+ return;
+
+ hsotg->core_params->speed = speed;
+ queue_work(hsotg->wq_otg, &hsotg->wf_otg);
+}
+
+static int dwc2_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
+{
+ struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
+
+ if (!hsotg->change_speed_quirk)
+ return 1;
+
+ hsotg->device_count++;
+ dev_info(hsotg->dev, "Device count is %u after alloc dev\n",
+ hsotg->device_count);
+
+ return 1;
+}
+
+static void dwc2_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
+{
+ struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
+
+ if (!hsotg->change_speed_quirk)
+ return;
+
+ if (hsotg->device_count)
+ hsotg->device_count--;
+
+ dev_info(hsotg->dev, "Device count is %u after free dev\n",
+ hsotg->device_count);
+
+ if (hsotg->device_count == 1 && 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->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) {
+ 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 +5092,12 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq)
dev_warn(hsotg->dev, "can't set coherent DMA mask\n");
}

+ if (hsotg->change_speed_quirk) {
+ dwc2_hc_driver.alloc_dev = dwc2_alloc_dev;
+ 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;
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 8e1728b..21c328b 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -585,6 +585,9 @@ static int dwc2_driver_probe(struct platform_device *dev)
dev_dbg(&dev->dev, "mapped PA %08lx to VA %p\n",
(unsigned long)res->start, hsotg->regs);

+ hsotg->change_speed_quirk = device_property_read_bool(&dev->dev,
+ "hi6220,change_speed_quirk");
+
retval = dwc2_lowlevel_hw_init(hsotg);
if (retval)
return retval;
--
2.7.4
\
 
 \ /
  Last update: 2016-10-14 01:39    [W:0.067 / U:2.572 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site