pinctrl: sunxi: Support I/O bias voltage setting on H6

H6 SoC has a "pio group withstand voltage mode" register (datasheet
description), that needs to be used to select either 1.8V or 3.3V I/O mode,
based on what voltage is powering the respective pin banks and is thus used
for I/O signals.

Add support for configuring this register according to the voltage of the
pin bank regulator (if enabled).

This is similar to the support for I/O bias voltage setting patch for A80
and the same concerns apply. See:

  commit 402bfb3c1352 ("Support I/O bias voltage setting on A80")

Signed-off-by: Ondrej Jirman <megous@megous.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.c b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
index 98c4de5f4019..0cbca30b75dc 100644
--- a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
+++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
@@ -614,6 +614,8 @@ static int sunxi_pinctrl_set_io_bias_cfg(struct sunxi_pinctrl *pctl,
 					 unsigned pin,
 					 struct regulator *supply)
 {
+	unsigned short bank = pin / PINS_PER_BANK;
+	unsigned long flags;
 	u32 val, reg;
 	int uV;
 
@@ -651,6 +653,15 @@ static int sunxi_pinctrl_set_io_bias_cfg(struct sunxi_pinctrl *pctl,
 		reg &= ~IO_BIAS_MASK;
 		writel(reg | val, pctl->membase + sunxi_grp_config_reg(pin));
 		return 0;
+	case BIAS_VOLTAGE_PIO_POW_MODE_SEL:
+		val = uV <= 1800000 ? 1 : 0;
+
+		raw_spin_lock_irqsave(&pctl->lock, flags);
+		reg = readl(pctl->membase + PIO_POW_MOD_SEL_REG);
+		reg &= ~(1 << bank);
+		writel(reg | val << bank, pctl->membase + PIO_POW_MOD_SEL_REG);
+		raw_spin_unlock_irqrestore(&pctl->lock, flags);
+		return 0;
 	default:
 		return -EINVAL;
 	}