pinctrl: mediatek: extend struct mtk_pin_field_calc to pinctrl-mtk-common-v2.c

This patch adds members sz_reg fixed in struct mtk_pin_field_calc

- The 'fixed' is used to represent the consecutive pins share the same
bits within the same register with the 1st pin so that it can largely
reduce the entry size a bit.

- The 'sz_reg' is used to indicate the range of bits we use in a register
  that may vary by SoC

The above changes make the code more generic and this is useful as there
might be other existing or future chips all use the same logic to access
their register set and then being a little more abstract could help in the
long run.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 11 insertions, 6 deletions

diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
index a74c3ffda67a..2a168043a6f0 100644
--- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
+++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
@@ -54,19 +54,24 @@ static int mtk_hw_pin_field_lookup(struct mtk_pinctrl *hw, int pin,
 		return -EINVAL;
 	}
 
-	/* Caculated bits as the overall offset the pin is located at */
-	bits = c->s_bit + (pin - c->s_pin) * (c->x_bits);
+	/* Calculated bits as the overall offset the pin is located at,
+	 * if c->fixed is held, that determines the all the pins in the
+	 * range use the same field with the s_pin.
+	 */
+	bits = c->fixed ? c->s_bit : c->s_bit + (pin - c->s_pin) * (c->x_bits);
 
-	/* Fill pfd from bits and 32-bit register applied is assumed */
-	pfd->offset = c->s_addr + c->x_addrs * (bits / 32);
-	pfd->bitpos = bits % 32;
+	/* Fill pfd from bits. For example 32-bit register applied is assumed
+	 * when c->sz_reg is equal to 32.
+	 */
+	pfd->offset = c->s_addr + c->x_addrs * (bits / c->sz_reg);
+	pfd->bitpos = bits % c->sz_reg;
 	pfd->mask = (1 << c->x_bits) - 1;
 
 	/* pfd->next is used for indicating that bit wrapping-around happens
 	 * which requires the manipulation for bit 0 starting in the next
 	 * register to form the complete field read/write.
 	 */
-	pfd->next = pfd->bitpos + c->x_bits - 1 > 31 ? c->x_addrs : 0;
+	pfd->next = pfd->bitpos + c->x_bits > c->sz_reg ? c->x_addrs : 0;
 
 	return 0;
 }