pinctrl: sh-pfc: Add helper to handle bias lookup table

On some SoC there are no simple mapping of pins to bias register bits
and a lookup table is needed. This logic is already implemented in some
SoC specific drivers that could benefit from a generic implementation.

Add helpers to deal with the lookup which later can be used by the SoC
specific drivers. The logic used to lookup are different from the one it
aims to replace, this is intentional. This new method reduces the memory
consumption at the cost of increased CPU usage and fix a bug where a
WARN() would incorrectly be triggered if the register offset is 0.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/pinctrl/sh-pfc/sh_pfc.h b/drivers/pinctrl/sh-pfc/sh_pfc.h
index 2345421103db..9556c172e3d2 100644
--- a/drivers/pinctrl/sh-pfc/sh_pfc.h
+++ b/drivers/pinctrl/sh-pfc/sh_pfc.h
@@ -189,6 +189,12 @@ struct sh_pfc_window {
 	unsigned long size;
 };
 
+struct sh_pfc_bias_info {
+	u16 pin;
+	u16 reg : 11;
+	u16 bit : 5;
+};
+
 struct sh_pfc_pin_range;
 
 struct sh_pfc {