USB: dwc3: gadget: Reset device core before setting Run/stop bit
When cable is disconnected, SW does device initiated disconnect
by clearing run/stop bit in DCTL register. When software wants to
reconnect to host, it has to do soft reset USB core and then
do device reinitialization.
By default max burst size for for control endpoints are initialized
to zero. This leads to setting burst size to non zero value for
control endpoints as part of reenabling endpoint 0 and 1 which results
in command queued for ep0 out getting timed out. Hence fix this by
initializing burst size to one in udc_start() API.
CRs-Fixed: 494807
Change-Id: I0a23ae8bc80932f9f66f792a1149ad5d8ac7d4a2
Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index bb2879b..db6fec9 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -264,7 +264,7 @@
*
* Returns 0 on success otherwise negative errno.
*/
-static int dwc3_event_buffers_setup(struct dwc3 *dwc)
+int dwc3_event_buffers_setup(struct dwc3 *dwc)
{
struct dwc3_event_buffer *evt;
int n;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 5db7420..2064c13 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -920,6 +920,7 @@
void dwc3_gadget_restart(struct dwc3 *dwc);
void dwc3_post_host_reset_core_init(struct dwc3 *dwc);
+int dwc3_event_buffers_setup(struct dwc3 *dwc);
extern int dwc3_get_device_id(void);
extern void dwc3_put_device_id(int id);
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 63698de..acda980 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -43,6 +43,7 @@
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
+#include <linux/ratelimit.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/list.h>
@@ -1487,10 +1488,12 @@
return 0;
}
+#define DWC3_SOFT_RESET_TIMEOUT 10 /* 10 msec */
static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on)
{
u32 reg;
u32 timeout = 500;
+ ktime_t start, diff;
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
if (is_on) {
@@ -1501,6 +1504,29 @@
if (dwc->revision >= DWC3_REVISION_194A)
reg &= ~DWC3_DCTL_KEEP_CONNECT;
+
+ start = ktime_get();
+ /* issue device SoftReset */
+ dwc3_writel(dwc->regs, DWC3_DCTL, reg | DWC3_DCTL_CSFTRST);
+ do {
+ reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+ if (!(reg & DWC3_DCTL_CSFTRST))
+ break;
+
+ diff = ktime_sub(ktime_get(), start);
+ /* poll for max. 10ms */
+ if (ktime_to_ms(diff) > DWC3_SOFT_RESET_TIMEOUT) {
+ printk_ratelimited(KERN_ERR
+ "%s:core Reset Timed Out\n", __func__);
+ break;
+ }
+ cpu_relax();
+ } while (true);
+
+
+ dwc3_event_buffers_setup(dwc);
+ dwc3_gadget_restart(dwc);
+ reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg |= DWC3_DCTL_RUN_STOP;
} else {
reg &= ~DWC3_DCTL_RUN_STOP;
@@ -1754,6 +1780,7 @@
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
dep = dwc->eps[0];
+ dep->endpoint.maxburst = 1;
ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false);
if (ret) {
dev_err(dwc->dev, "failed to enable %s\n", dep->name);
@@ -1761,6 +1788,7 @@
}
dep = dwc->eps[1];
+ dep->endpoint.maxburst = 1;
ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false);
if (ret) {
dev_err(dwc->dev, "failed to enable %s\n", dep->name);