pinctrl: microchip sgpio: use reset driver

On lan966x platform when the switch gets reseted then also the sgpio
gets reseted. The fix for this is to extend also the sgpio driver to
call the reset driver which will be reseted only once by the first
driver that is probed.

Signed-off-by: Horatiu Vultur <[e-mail]>
Reviewed-by: Steen Hegelund <[e-mail]>
Reviewed-by: Philipp Zabel <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/pinctrl-microchip-sgpio.c

···
 #include <linux/pinctrl/pinmux.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
+#include <linux/reset.h>
 
 #include "core.h"
 #include "pinconf.h"
···
 	int div_clock = 0, ret, port, i, nbanks;
 	struct device *dev = &pdev->dev;
 	struct fwnode_handle *fwnode;
+	struct reset_control *reset;
 	struct sgpio_priv *priv;
 	struct clk *clk;
 	u32 val;
···
 		return -ENOMEM;
 
 	priv->dev = dev;
+
+	reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");
+	if (IS_ERR(reset))
+		return dev_err_probe(dev, PTR_ERR(reset), "Failed to get reset\n");
+	reset_control_reset(reset);
 
 	clk = devm_clk_get(dev, NULL);
 	if (IS_ERR(clk))