pinctrl: pinmux: Don't free pins requested by other devices in pinmux_disable_setting.

One peripheral may share part of its pins with the 2nd
peripheral and the other pins with the 3rd. If it requests all pins
when part of them has already be requested and owned by the 2nd
peripheral, this request fails and pinmux_disable_setting() is called.
The pinmux_disable_setting() frees all pins of the first peripheral
without checking if the pin is owned by itself or the 2nd, which
results in the malfunction of the 2nd peripheral driver.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinmux.c

@@ -482,13 +482,13 @@ void pinmux_disable_setting(struct pinctrl_setting const *setting)
 				 pins[i]);
 			continue;
 		}
-		desc->mux_setting = NULL;
+		if (desc->mux_setting == &(setting->data.mux)) {
+			desc->mux_setting = NULL;
+			/* And release the pin */
+			pin_free(pctldev, pins[i], NULL);
+		}
 	}
 
-	/* And release the pins */
-	for (i = 0; i < num_pins; i++)
-		pin_free(pctldev, pins[i], NULL);
-
 	if (ops->disable)
 		ops->disable(pctldev, setting->data.mux.func, setting->data.mux.group);
 }