[12/20] phy: rcar-gen3-usb2: add sysfs for usb role swap

diff --git a/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2 b/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2
new file mode 100644
index 0000000..6212697
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-platform-phy-rcar-gen3-usb2
@@ -0,0 +1,15 @@ 
+What:		/sys/devices/platform/<phy-name>/role
+Date:		October 2016
+KernelVersion:	4.10
+Contact:	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
+Description:
+		This file can be read and write.
+		The file can show/change the phy mode for role swap of usb.
+
+		Write the following strings to change the mode:
+		 "host" - switching mode from peripheral to host.
+		 "peripheral" - switching mode from host to peripheral.
+
+		Read the file, then it shows the following strings:
+		 "host" - The mode is host now.
+		 "peripheral" - The mode is peripheral now.
diff --git a/drivers/phy/phy-rcar-gen3-usb2.c b/drivers/phy/phy-rcar-gen3-usb2.c
index 3d97ead..c63da1b 100644
--- a/drivers/phy/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/phy-rcar-gen3-usb2.c
@@ -70,6 +70,7 @@ 
 #define USB2_LINECTRL1_DP_RPD		BIT(18)
 #define USB2_LINECTRL1_DMRPD_EN		BIT(17)
 #define USB2_LINECTRL1_DM_RPD		BIT(16)
+#define USB2_LINECTRL1_OPMODE_NODRV	BIT(6)
 
 /* ADPCTRL */
 #define USB2_ADPCTRL_OTGSESSVLD		BIT(20)
@@ -161,6 +162,43 @@  static void rcar_gen3_init_for_peri(struct rcar_gen3_chan *ch)
 	schedule_work(&ch->work);
 }
 
+static void rcar_gen3_init_for_b_host(struct rcar_gen3_chan *ch)
+{
+	void __iomem *usb2_base = ch->base;
+	u32 val;
+
+	val = readl(usb2_base + USB2_LINECTRL1);
+	writel(val | USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1);
+
+	rcar_gen3_set_linectrl(ch, 1, 1);
+	rcar_gen3_set_host_mode(ch, 1);
+	rcar_gen3_enable_vbus_ctrl(ch, 0);
+
+	val = readl(usb2_base + USB2_LINECTRL1);
+	writel(val & ~USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1);
+}
+
+static void rcar_gen3_init_for_a_peri(struct rcar_gen3_chan *ch)
+{
+	rcar_gen3_set_linectrl(ch, 0, 1);
+	rcar_gen3_set_host_mode(ch, 0);
+	rcar_gen3_enable_vbus_ctrl(ch, 1);
+}
+
+static void rcar_gen3_init_from_a_peri_to_a_host(struct rcar_gen3_chan *ch)
+{
+	void __iomem *usb2_base = ch->base;
+	u32 val;
+
+	val = readl(usb2_base + USB2_OBINTEN);
+	writel(val & ~USB2_OBINT_BITS, usb2_base + USB2_OBINTEN);
+
+	rcar_gen3_enable_vbus_ctrl(ch, 0);
+	rcar_gen3_init_for_host(ch);
+
+	writel(val | USB2_OBINT_BITS, usb2_base + USB2_OBINTEN);
+}
+
 static bool rcar_gen3_check_id(struct rcar_gen3_chan *ch)
 {
 	return !!(readl(ch->base + USB2_ADPCTRL) & USB2_ADPCTRL_IDDIG);
@@ -174,6 +212,65 @@  static void rcar_gen3_device_recognition(struct rcar_gen3_chan *ch)
 		rcar_gen3_init_for_peri(ch);
 }
 
+static bool rcar_gen3_is_host(struct rcar_gen3_chan *ch)
+{
+	return !(readl(ch->base + USB2_COMMCTRL) & USB2_COMMCTRL_OTG_PERI);
+}
+
+static ssize_t role_store(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct rcar_gen3_chan *ch = dev_get_drvdata(dev);
+	bool is_b_device, is_host, new_mode_is_host;
+
+	if (!ch->has_otg || !ch->phy->init_count)
+		return -EIO;
+
+	/*
+	 * is_b_device: true is B-Device. false is A-Device.
+	 * If {new_mode_}is_host: true is Host mode. false is Peripheral mode.
+	 */
+	is_b_device = rcar_gen3_check_id(ch);
+	is_host = rcar_gen3_is_host(ch);
+	if (!strncmp(buf, "host", strlen("host")))
+		new_mode_is_host = true;
+	else if (!strncmp(buf, "peripheral", strlen("peripheral")))
+		new_mode_is_host = false;
+	else
+		return -EINVAL;
+
+	/* If current and new mode is the same, this returns the error */
+	if (is_host == new_mode_is_host)
+		return -EINVAL;
+
+	if (new_mode_is_host) {		/* And is_host must be false */
+		if (!is_b_device)	/* A-Peripheral */
+			rcar_gen3_init_from_a_peri_to_a_host(ch);
+		else			/* B-Peripheral */
+			rcar_gen3_init_for_b_host(ch);
+	} else {			/* And is_host must be true */
+		if (!is_b_device)	/* A-Host */
+			rcar_gen3_init_for_a_peri(ch);
+		else			/* B-Host */
+			rcar_gen3_init_for_peri(ch);
+	}
+
+	return count;
+}
+
+static ssize_t role_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct rcar_gen3_chan *ch = dev_get_drvdata(dev);
+
+	if (!ch->has_otg || !ch->phy->init_count)
+		return -EIO;
+
+	return sprintf(buf, "%s\n", rcar_gen3_is_host(ch) ? "host" :
+							    "peripheral");
+}
+static DEVICE_ATTR_RW(role);
+
 static void rcar_gen3_init_otg(struct rcar_gen3_chan *ch)
 {
 	void __iomem *usb2_base = ch->base;
@@ -351,21 +448,40 @@  static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
 		channel->vbus = NULL;
 	}
 
+	platform_set_drvdata(pdev, channel);
 	phy_set_drvdata(channel->phy, channel);
 
 	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
-	if (IS_ERR(provider))
+	if (IS_ERR(provider)) {
 		dev_err(dev, "Failed to register PHY provider\n");
+	} else if (channel->has_otg) {
+		int ret;
+
+		ret = device_create_file(dev, &dev_attr_role);
+		if (ret < 0)
+			return ret;
+	}
 
 	return PTR_ERR_OR_ZERO(provider);
 }
 
+static int rcar_gen3_phy_usb2_remove(struct platform_device *pdev)
+{
+	struct rcar_gen3_chan *channel = platform_get_drvdata(pdev);
+
+	if (channel->has_otg)
+		device_remove_file(&pdev->dev, &dev_attr_role);
+
+	return 0;
+};
+
 static struct platform_driver rcar_gen3_phy_usb2_driver = {
 	.driver = {
 		.name		= "phy_rcar_gen3_usb2",
 		.of_match_table	= rcar_gen3_phy_usb2_match_table,
 	},
 	.probe	= rcar_gen3_phy_usb2_probe,
+	.remove = rcar_gen3_phy_usb2_remove,
 };
 module_platform_driver(rcar_gen3_phy_usb2_driver);