We initiate dwc2 usb controller in BIOS, when kernel driver
start-up we should reset AHB hclk domain to reset all AHB
interface registers to default. Without this the FIFO value
setting might be incorrect because calculating FIFO size need the
power-on value of GRXFSIZ/GNPTXFSIZ/HPTXFSIZ registers.
This patch could avoid warnning massage like in rk3288 platform:
[ 2.074764] dwc2 ff580000.usb: 256 invalid for
host_perio_tx_fifo_size. Check HW configuration.
Signed-off-by: Yunzhi Li <lyz@xxxxxxxxxxxxxx>
---
drivers/usb/dwc2/platform.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 9093530..3da21ab 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -42,6 +42,7 @@
#include <linux/of_device.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
+#include <linux/reset.h>
#include <linux/usb/of.h>
@@ -165,6 +166,7 @@ static int dwc2_driver_probe(struct platform_device *dev)
struct resource *res;
struct phy *phy;
struct usb_phy *uphy;
+ struct reset_control *rst;
int retval;
int irq;
@@ -189,6 +191,16 @@ static int dwc2_driver_probe(struct platform_device *dev)
hsotg->dev = &dev->dev;
+ /* AHB hclk domain reset, set all AHB interface registers to default */
+ rst = devm_reset_control_get_optional(&dev->dev, "ahb_reset");
+ if (IS_ERR(rst)) {
+ dev_dbg(&dev->dev, "Can't get dwc2 AHB reset\n");
+ } else {
+ reset_control_assert(rst);
+ udelay(5);
+ reset_control_deassert(rst);
+ }
+
/*
* Use reasonable defaults so platforms don't have to provide these.
*/
--
2.0.0
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
