usb: musb: Fix idling after host mode by increasing autosuspend delay

Looks like at least 2430 glue won't idle reliably with the 200 ms
autosuspend delay. This causes deeper idle states being blocked for
the whole SoC when disconnecting OTG A cable.

Increasing the delay to 500 ms seems to idle both MUSB and the PHY
reliably. This is probably because of time needed by the hardware
based negotiation between MUSB and the PHY.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 39fd95833eb8317b63f4f1e1a781f611bfcda5cd..460176c43e84a6fed668c4f0fde02ba96a3ec33e 100644 (file)
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2028,9 +2028,15 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
        musb_readl = musb_default_readl;
        musb_writel = musb_default_writel;
 
-       /* We need musb_read/write functions initialized for PM */
+       /*
+        * We need musb_read/write functions initialized for PM.
+        * Note that at least 2430 glue needs autosuspend delay
+        * somewhere above 300 ms for the hardware to idle properly
+        * after disconnecting the cable in host mode. Let's use
+        * 500 ms for some margin.
+        */
        pm_runtime_use_autosuspend(musb->controller);
-       pm_runtime_set_autosuspend_delay(musb->controller, 200);
+       pm_runtime_set_autosuspend_delay(musb->controller, 500);
        pm_runtime_enable(musb->controller);
 
        /* The musb_platform_init() call: