From: Eugeniu Rosca <erosca@xxxxxxxxxxxxxx>
Commit [1] enabled the possibility of checking the DVST (Device State
Transition) bit of INTSTS0 (Interrupt Status Register 0) and calling
the irq_dev_state() handler if the DVST bit is set. But neither
commit [1] nor commit [2] actually enabled the DVSE (Device State
Transition Interrupt Enable) bit in the INTENB0 (Interrupt Enable
Register 0). As a consequence, irq_dev_state() handler is getting
called as a side effect of other (non-DVSE) interrupts being fired,
which definitely can't be relied upon, if DVST notifications are of
any value.
Why this doesn't hurt is because usbhsg_irq_dev_state() currently
doesn't do much except of a dev_dbg(). Once more work is added to
the handler (e.g. detecting device "Suspended" state and notifying
other USB gadget components about it), enabling DVSE becomes a hard
requirement. Do it in a standalone commit for better visibility and
clear explanation.
[1] f1407d5 ("usb: renesas_usbhs: Add Renesas USBHS common code")
[2] 2f98382 ("usb: renesas_usbhs: Add Renesas USBHS Gadget")
Signed-off-by: Eugeniu Rosca <erosca@xxxxxxxxxxxxxx>
---
v2: No change
v1: https://patchwork.kernel.org/patch/10581479/
drivers/usb/renesas_usbhs/mod.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/renesas_usbhs/mod.c b/drivers/usb/renesas_usbhs/mod.c
index 7475c4f64724..87e08b1512ad 100644
--- a/drivers/usb/renesas_usbhs/mod.c
+++ b/drivers/usb/renesas_usbhs/mod.c
@@ -349,10 +349,6 @@ void usbhs_irq_callback_update(struct usbhs_priv *priv, struct usbhs_mod *mod)
* usbhs_interrupt
*/
- /*
- * it don't enable DVSE (intenb0) here
- * but "mod->irq_dev_state" will be called.
- */
if (info->irq_vbus)
intenb0 |= VBSE;
@@ -363,6 +359,9 @@ void usbhs_irq_callback_update(struct usbhs_priv *priv, struct usbhs_mod *mod)
if (mod->irq_ctrl_stage)
intenb0 |= CTRE;
+ if (mod->irq_dev_state)
+ intenb0 |= DVSE;
+
if (mod->irq_empty && mod->irq_bempsts) {
usbhs_write(priv, BEMPENB, mod->irq_bempsts);
intenb0 |= BEMPE;
--
2.7.4
