usb: dwc2: Avoid double-reset at boot time
In (usb: dwc2: reset dwc2 core before dwc2_get_hwparams()) we added an
extra reset to the probe path for the dwc2 USB controllers. This
allowed proper detection of parameters even if the firmware had already
used the USB part.
Unfortunately, this extra reset is quite slow and is affecting boot
speed. We can avoid the double-reset by skipping the extra reset that
would happen just after the one we added. Logic that explains why this
is safe:
* As of the CL mentioned above, we now always call dwc2_core_reset() in
dwc2_driver_probe() before dwc2_hcd_init().
* The only caller of dwc2_hcd_init() is dwc2_driver_probe(), so we're
guaranteed that dwc2_core_reset() was called before dwc2_hdc_init().
* dwc2_hdc_init() is the only caller that passes an irq other than -1 to
dwc2_core_init(). Thus if dwc2_core_init() is called with an irq
other than -1 we're guaranteed that dwc2_core_reset was called before
dwc2_core_init().
...this allows us to remove the dwc2_core_reset() in dwc2_core_init() if
irq is not < 0.
Note that since "irq" wasn't used in the function dwc2_core_init()
anyway and since select_phy was always set at exactly the same times we
could avoid the reset, we remove "irq" and rename "select_phy" to
"initial_setup" and adjust the callers accordingly.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index d1d855a..cbece3a 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -918,7 +918,7 @@
extern void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num);
extern void dwc2_flush_rx_fifo(struct dwc2_hsotg *hsotg);
-extern int dwc2_core_init(struct dwc2_hsotg *hsotg, bool select_phy, int irq);
+extern int dwc2_core_init(struct dwc2_hsotg *hsotg, bool initial_setup);
extern void dwc2_enable_global_interrupts(struct dwc2_hsotg *hcd);
extern void dwc2_disable_global_interrupts(struct dwc2_hsotg *hcd);