usb: phy: phy-gpio-vbus-usb: Convert to GPIO descriptors

Instead of using the legacy GPIO API and keeping track on
polarity inversion semantics in the driver, switch to use
GPIO descriptors for this driver and change all consumers
in the process.

This makes it possible to retire platform data completely:
the only remaining platform data member was "wakeup" which
was intended to make the vbus interrupt wakeup capable,
but was not set by any users and thus remained unused. VBUS
was not waking any devices up. Leave a comment about it so
later developers using the platform can consider setting it
to always enabled so plugging in USB wakes up the platform.

Cc: Daniel Mack <daniel@zonque.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Sylwester Nawrocki <snawrocki@kernel.org>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200123155013.93249-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 43 insertions, 53 deletions

diff --git a/drivers/usb/phy/phy-gpio-vbus-usb.c b/drivers/usb/phy/phy-gpio-vbus-usb.c
index 553e2573c74f..f13f5530746c 100644
--- a/drivers/usb/phy/phy-gpio-vbus-usb.c
+++ b/drivers/usb/phy/phy-gpio-vbus-usb.c
@@ -7,7 +7,7 @@
 
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/interrupt.h>
@@ -17,7 +17,6 @@
 #include <linux/regulator/consumer.h>
 
 #include <linux/usb/gadget.h>
-#include <linux/usb/gpio_vbus.h>
 #include <linux/usb/otg.h>
 
 
@@ -29,6 +28,8 @@
  * Needs to be loaded before the UDC driver that will use it.
  */
 struct gpio_vbus_data {
+	struct gpio_desc	*vbus_gpiod;
+	struct gpio_desc	*pullup_gpiod;
 	struct usb_phy		phy;
 	struct device          *dev;
 	struct regulator       *vbus_draw;
@@ -83,38 +84,30 @@ static void set_vbus_draw(struct gpio_vbus_data *gpio_vbus, unsigned mA)
 	gpio_vbus->mA = mA;
 }
 
-static int is_vbus_powered(struct gpio_vbus_mach_info *pdata)
+static int is_vbus_powered(struct gpio_vbus_data *gpio_vbus)
 {
-	int vbus;
-
-	vbus = gpio_get_value(pdata->gpio_vbus);
-	if (pdata->gpio_vbus_inverted)
-		vbus = !vbus;
-
-	return vbus;
+	return gpiod_get_value(gpio_vbus->vbus_gpiod);
 }
 
 static void gpio_vbus_work(struct work_struct *work)
 {
 	struct gpio_vbus_data *gpio_vbus =
 		container_of(work, struct gpio_vbus_data, work.work);
-	struct gpio_vbus_mach_info *pdata = dev_get_platdata(gpio_vbus->dev);
-	int gpio, status, vbus;
+	int status, vbus;
 
 	if (!gpio_vbus->phy.otg->gadget)
 		return;
 
-	vbus = is_vbus_powered(pdata);
+	vbus = is_vbus_powered(gpio_vbus);
 	if ((vbus ^ gpio_vbus->vbus) == 0)
 		return;
 	gpio_vbus->vbus = vbus;
 
 	/* Peripheral controllers which manage the pullup themselves won't have
-	 * gpio_pullup configured here.  If it's configured here, we'll do what
-	 * isp1301_omap::b_peripheral() does and enable the pullup here... although
-	 * that may complicate usb_gadget_{,dis}connect() support.
+	 * a pullup GPIO configured here.  If it's configured here, we'll do
+	 * what isp1301_omap::b_peripheral() does and enable the pullup here...
+	 * although that may complicate usb_gadget_{,dis}connect() support.
 	 */
-	gpio = pdata->gpio_pullup;
 
 	if (vbus) {
 		status = USB_EVENT_VBUS;
@@ -126,16 +119,16 @@ static void gpio_vbus_work(struct work_struct *work)
 		set_vbus_draw(gpio_vbus, 100);
 
 		/* optionally enable D+ pullup */
-		if (gpio_is_valid(gpio))
-			gpio_set_value(gpio, !pdata->gpio_pullup_inverted);
+		if (gpio_vbus->pullup_gpiod)
+			gpiod_set_value(gpio_vbus->pullup_gpiod, 1);
 
 		atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
 					   status, gpio_vbus->phy.otg->gadget);
 		usb_phy_set_event(&gpio_vbus->phy, USB_EVENT_ENUMERATED);
 	} else {
 		/* optionally disable D+ pullup */
-		if (gpio_is_valid(gpio))
-			gpio_set_value(gpio, pdata->gpio_pullup_inverted);
+		if (gpio_vbus->pullup_gpiod)
+			gpiod_set_value(gpio_vbus->pullup_gpiod, 0);
 
 		set_vbus_draw(gpio_vbus, 0);
 
@@ -154,12 +147,11 @@ static void gpio_vbus_work(struct work_struct *work)
 static irqreturn_t gpio_vbus_irq(int irq, void *data)
 {
 	struct platform_device *pdev = data;
-	struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
 	struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
 	struct usb_otg *otg = gpio_vbus->phy.otg;
 
 	dev_dbg(&pdev->dev, "VBUS %s (gadget: %s)\n",
-		is_vbus_powered(pdata) ? "supplied" : "inactive",
+		is_vbus_powered(gpio_vbus) ? "supplied" : "inactive",
 		otg->gadget ? otg->gadget->name : "none");
 
 	if (otg->gadget)
@@ -175,22 +167,18 @@ static int gpio_vbus_set_peripheral(struct usb_otg *otg,
 					struct usb_gadget *gadget)
 {
 	struct gpio_vbus_data *gpio_vbus;
-	struct gpio_vbus_mach_info *pdata;
 	struct platform_device *pdev;
-	int gpio;
 
 	gpio_vbus = container_of(otg->usb_phy, struct gpio_vbus_data, phy);
 	pdev = to_platform_device(gpio_vbus->dev);
-	pdata = dev_get_platdata(gpio_vbus->dev);
-	gpio = pdata->gpio_pullup;
 
 	if (!gadget) {
 		dev_dbg(&pdev->dev, "unregistering gadget '%s'\n",
 			otg->gadget->name);
 
 		/* optionally disable D+ pullup */
-		if (gpio_is_valid(gpio))
-			gpio_set_value(gpio, pdata->gpio_pullup_inverted);
+		if (gpio_vbus->pullup_gpiod)
+			gpiod_set_value(gpio_vbus->pullup_gpiod, 0);
 
 		set_vbus_draw(gpio_vbus, 0);
 
@@ -242,16 +230,12 @@ static int gpio_vbus_set_suspend(struct usb_phy *phy, int suspend)
 
 static int gpio_vbus_probe(struct platform_device *pdev)
 {
-	struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
 	struct gpio_vbus_data *gpio_vbus;
 	struct resource *res;
-	int err, gpio, irq;
+	struct device *dev = &pdev->dev;
+	int err, irq;
 	unsigned long irqflags;
 
-	if (!pdata || !gpio_is_valid(pdata->gpio_vbus))
-		return -EINVAL;
-	gpio = pdata->gpio_vbus;
-
 	gpio_vbus = devm_kzalloc(&pdev->dev, sizeof(struct gpio_vbus_data),
 				 GFP_KERNEL);
 	if (!gpio_vbus)
@@ -273,37 +257,43 @@ static int gpio_vbus_probe(struct platform_device *pdev)
 	gpio_vbus->phy.otg->usb_phy = &gpio_vbus->phy;
 	gpio_vbus->phy.otg->set_peripheral = gpio_vbus_set_peripheral;
 
-	err = devm_gpio_request(&pdev->dev, gpio, "vbus_detect");
-	if (err) {
-		dev_err(&pdev->dev, "can't request vbus gpio %d, err: %d\n",
-			gpio, err);
+	/* Look up the VBUS sensing GPIO */
+	gpio_vbus->vbus_gpiod = devm_gpiod_get(dev, "vbus", GPIOD_IN);
+	if (IS_ERR(gpio_vbus->vbus_gpiod)) {
+		err = PTR_ERR(gpio_vbus->vbus_gpiod);
+		dev_err(&pdev->dev, "can't request vbus gpio, err: %d\n", err);
 		return err;
 	}
-	gpio_direction_input(gpio);
+	gpiod_set_consumer_name(gpio_vbus->vbus_gpiod, "vbus_detect");
 
 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (res) {
 		irq = res->start;
 		irqflags = (res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
 	} else {
-		irq = gpio_to_irq(gpio);
+		irq = gpiod_to_irq(gpio_vbus->vbus_gpiod);
 		irqflags = VBUS_IRQ_FLAGS;
 	}
 
 	gpio_vbus->irq = irq;
 
-	/* if data line pullup is in use, initialize it to "not pulling up" */
-	gpio = pdata->gpio_pullup;
-	if (gpio_is_valid(gpio)) {
-		err = devm_gpio_request(&pdev->dev, gpio, "udc_pullup");
-		if (err) {
-			dev_err(&pdev->dev,
-				"can't request pullup gpio %d, err: %d\n",
-				gpio, err);
-			return err;
-		}
-		gpio_direction_output(gpio, pdata->gpio_pullup_inverted);
+	/*
+	 * The VBUS sensing GPIO should have a pulldown, which will normally be
+	 * part of a resistor ladder turning a 4.0V-5.25V level on VBUS into a
+	 * value the GPIO detects as active. Some systems will use comparators.
+	 * Get the optional D+ or D- pullup GPIO. If the data line pullup is
+	 * in use, initialize it to "not pulling up"
+	 */
+	gpio_vbus->pullup_gpiod = devm_gpiod_get_optional(dev, "pullup",
+							  GPIOD_OUT_LOW);
+	if (IS_ERR(gpio_vbus->pullup_gpiod)) {
+		err = PTR_ERR(gpio_vbus->pullup_gpiod);
+		dev_err(&pdev->dev, "can't request pullup gpio, err: %d\n",
+			err);
+		return err;
 	}
+	if (gpio_vbus->pullup_gpiod)
+		gpiod_set_consumer_name(gpio_vbus->pullup_gpiod, "udc_pullup");
 
 	err = devm_request_irq(&pdev->dev, irq, gpio_vbus_irq, irqflags,
 			       "vbus_detect", pdev);
@@ -330,7 +320,7 @@ static int gpio_vbus_probe(struct platform_device *pdev)
 		return err;
 	}
 
-	device_init_wakeup(&pdev->dev, pdata->wakeup);
+	/* TODO: wakeup could be enabled here with device_init_wakeup(dev, 1) */
 
 	return 0;
 }