The sunxi_pconf_reg helper introduced in the last patch gives us the
chance to rework sunxi_pconf_group_set to have it match the structure
of sunxi_pconf_(group_)get and make it easier to understand.

For each config to set, it:

    1. checks if the parameter is supported.
    2. checks if the argument is within limits.
    3. converts argument to the register value.
    4. writes to the register with spinlock held.

As a result the function now blocks unsupported config parameters,
instead of silently ignoring them.

Signed-off-by: Chen-Yu Tsai <redacted>
---
 drivers/pinctrl/sunxi/pinctrl-sunxi.c | 65 +++++++++++++++++++----------------
 drivers/pinctrl/sunxi/pinctrl-sunxi.h |  1 -
 2 files changed, 35 insertions(+), 31 deletions(-)

diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.c b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
index 236272a2339d..1f02c4cd55c7 100644
--- a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
+++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.c

@@ -364,23 +364,27 @@ static int sunxi_pconf_group_set(struct pinctrl_dev *pctldev,
 {
 	struct sunxi_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
 	struct sunxi_pinctrl_group *g = &pctl->groups[group];
-	unsigned long flags;
 	unsigned pin = g->pin - pctl->desc->pin_base;
-	u32 val, mask;
-	u16 strength;
-	u8 dlevel;
 	int i;
 
-	spin_lock_irqsave(&pctl->lock, flags);
-
 	for (i = 0; i < num_configs; i++) {
-		switch (pinconf_to_config_param(configs[i])) {
+		enum pin_config_param param;
+		unsigned long flags;
+		u32 offset, shift, mask, val;
+		u16 arg;
+		int ret;
+
+		param = pinconf_to_config_param(configs[i]);
+		arg = pinconf_to_config_argument(configs[i]);
+
+		ret = sunxi_pconf_reg(pin, param, &offset, &shift, &mask);
+		if (ret < 0)
+			return ret;
+
+		switch (param) {
 		case PIN_CONFIG_DRIVE_STRENGTH:
-			strength = pinconf_to_config_argument(configs[i]);
-			if (strength > 40) {
-				spin_unlock_irqrestore(&pctl->lock, flags);
+			if (arg < 10 || arg > 40)