pinctrl: core: Handling pinmux and pinconf separately

mainline inclusion
from mainline-v5.13-rc1
commit b991f8c3
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60OLE
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b991f8c3622c8c9d01a1ada382682a731932e651

--------------------------------

Right now the handling order depends on how entries are coming which is
corresponding with order in DT. We have reached the case with DT overlays
where conf and mux descriptions are exchanged which ends up in sequence
that firmware has been asked to perform configuration before requesting the
pin.

The patch is enforcing the order that pin is requested all the time first
followed by pin configuration. This change will ensure that firmware gets
requests in the right order.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/cfbe01f791c2dd42a596cbda57e15599969b57aa.1615364211.git.michal.simek@xilinx.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NYuyao Lin <linyuyao1@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/pinctrl/core.c

@@ -1258,13 +1258,34 @@ static int pinctrl_commit_state(struct pinctrl *p, struct pinctrl_state *state)
 
 	p->state = NULL;
 
-	/* Apply all the settings for the new state */
+	/* Apply all the settings for the new state - pinmux first */
 	list_for_each_entry(setting, &state->settings, node) {
 		switch (setting->type) {
 		case PIN_MAP_TYPE_MUX_GROUP:
 			ret = pinmux_enable_setting(setting);
 			break;
 		case PIN_MAP_TYPE_CONFIGS_PIN:
+		case PIN_MAP_TYPE_CONFIGS_GROUP:
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+
+		if (ret < 0)
+			goto unapply_new_state;
+
+		/* Do not link hogs (circular dependency) */
+		if (p != setting->pctldev->p)
+			pinctrl_link_add(setting->pctldev, p->dev);
+	}
+
+	/* Apply all the settings for the new state - pinconf after */
+	list_for_each_entry(setting, &state->settings, node) {
+		switch (setting->type) {
+		case PIN_MAP_TYPE_MUX_GROUP:
+			break;
+		case PIN_MAP_TYPE_CONFIGS_PIN:
 		case PIN_MAP_TYPE_CONFIGS_GROUP:
 			ret = pinconf_apply_setting(setting);
 			break;