[PATCH v2] phy: renesas: rcar-gen3-usb2: Simplify ID/VBUS detection logic
From: Prabhakar
Date: Wed Mar 25 2026 - 07:36:56 EST
From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Read USB2_ADPCTRL once in rcar_gen3_check_id() instead of issuing
multiple MMIO reads, and derive both IDDIG and VBUSVALID from the same
value.
Drop the redundant !! operator, as assigning a masked u32 value to a
bool already performs the required normalization. Simplify the logic by
comparing the ID and VBUS status directly, which is equivalent to the
previous conditional but easier to follow.
Reported-by: Pavel Machek <pavel@xxxxxxxxxxxx>
Closes: https://lore.kernel.org/all/acJVCOdlchLiSe5n@xxxxxxxxxx/
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
---
v1->v2:
- Rebased on top of latest next-20260324
- Combined variable declarations and assignments and dropped
redundant !! operator
- Updated commit message
- Corrected the link for closes tag
---
drivers/phy/renesas/phy-rcar-gen3-usb2.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
index 79e820e2fe55..9a45d840efeb 100644
--- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
@@ -314,13 +314,11 @@ static void rcar_gen3_init_from_a_peri_to_a_host(struct rcar_gen3_chan *ch)
static bool rcar_gen3_check_id(struct rcar_gen3_chan *ch)
{
if (ch->phy_data->vblvl_ctrl) {
- bool vbus_valid;
- bool device;
+ u32 val = readl(ch->base + USB2_ADPCTRL);
+ bool vbus_valid = val & USB2_ADPCTRL_VBUSVALID;
+ bool device = val & USB2_ADPCTRL_IDDIG;
- device = !!(readl(ch->base + USB2_ADPCTRL) & USB2_ADPCTRL_IDDIG);
- vbus_valid = !!(readl(ch->base + USB2_ADPCTRL) & USB2_ADPCTRL_VBUSVALID);
-
- return vbus_valid ? device : !device;
+ return device == vbus_valid;
}
if (!ch->uses_otg_pins)
--
2.53.0