usb: chipidea: Add dynamic pinctrl selection

Some hardware implementations require to configure pins differently
according to the USB role (host/device), this can be an update of the
pins routing or a simple GPIO value change.

This patch introduces new optional "host" and "device" pinctrls.
If these pinctrls are defined by the device, they are respectively
selected on host/device role start.

If a default pinctrl exist, it is restored on host/device role stop.
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>

drivers/usb/chipidea/core.c

@@ -53,6 +53,7 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb/otg.h>
@@ -723,6 +724,24 @@ static int ci_get_platdata(struct device *dev,
 		else
 			cable->connected = false;
 	}
+
+	platdata->pctl = devm_pinctrl_get(dev);
+	if (!IS_ERR(platdata->pctl)) {
+		struct pinctrl_state *p;
+
+		p = pinctrl_lookup_state(platdata->pctl, "default");
+		if (!IS_ERR(p))
+			platdata->pins_default = p;
+
+		p = pinctrl_lookup_state(platdata->pctl, "host");
+		if (!IS_ERR(p))
+			platdata->pins_host = p;
+
+		p = pinctrl_lookup_state(platdata->pctl, "device");
+		if (!IS_ERR(p))
+			platdata->pins_device = p;
+	}
+
 	return 0;
 }
 

drivers/usb/chipidea/host.c

@@ -13,6 +13,7 @@
 #include <linux/usb/hcd.h>
 #include <linux/usb/chipidea.h>
 #include <linux/regulator/consumer.h>
+#include <linux/pinctrl/consumer.h>
 
 #include "../host/ehci.h"
 
@@ -153,6 +154,10 @@ static int host_start(struct ci_hdrc *ci)
 		}
 	}
 
+	if (ci->platdata->pins_host)
+		pinctrl_select_state(ci->platdata->pctl,
+				     ci->platdata->pins_host);
+
 	ret = usb_add_hcd(hcd, 0, 0);
 	if (ret) {
 		goto disable_reg;
@@ -197,6 +202,10 @@ static void host_stop(struct ci_hdrc *ci)
 	}
 	ci->hcd = NULL;
 	ci->otg.host = NULL;
+
+	if (ci->platdata->pins_host && ci->platdata->pins_default)
+		pinctrl_select_state(ci->platdata->pctl,
+				     ci->platdata->pins_default);
 }
 
 

drivers/usb/chipidea/udc.c

@@ -15,6 +15,7 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb/otg-fsm.h>
@@ -1965,6 +1966,10 @@ void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
 
 static int udc_id_switch_for_device(struct ci_hdrc *ci)
 {
+	if (ci->platdata->pins_device)
+		pinctrl_select_state(ci->platdata->pctl,
+				     ci->platdata->pins_device);
+
 	if (ci->is_otg)
 		/* Clear and enable BSV irq */
 		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
@@ -1983,6 +1988,10 @@ static void udc_id_switch_for_host(struct ci_hdrc *ci)
 		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
 
 	ci->vbus_active = 0;
+
+	if (ci->platdata->pins_device && ci->platdata->pins_default)
+		pinctrl_select_state(ci->platdata->pctl,
+				     ci->platdata->pins_default);
 }
 
 /**

include/linux/usb/chipidea.h

@@ -77,6 +77,12 @@ struct ci_hdrc_platform_data {
 	struct ci_hdrc_cable		vbus_extcon;
 	struct ci_hdrc_cable		id_extcon;
 	u32			phy_clkgate_delay_us;
+
+	/* pins */
+	struct pinctrl *pctl;
+	struct pinctrl_state *pins_default;
+	struct pinctrl_state *pins_host;
+	struct pinctrl_state *pins_device;
 };
 
 /* Default offset of capability registers */