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From: Peter Chen <peter.chen@nxp.com>
To: "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>
Cc: dl-linux-imx <linux-imx@nxp.com>,
	"robh+dt@kernel.org" <robh+dt@kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"frieder.schrempf@exceet.de" <frieder.schrempf@exceet.de>,
	"festevam@gmail.com" <festevam@gmail.com>,
	Peter Chen <peter.chen@nxp.com>
Subject: [v5,2/4] usb: chipidea: imx: add HSIC support
Date: Tue, 11 Dec 2018 02:08:57 +0000	[thread overview]
Message-ID: <20181211020624.9433-3-peter.chen@nxp.com> (raw)

To support imx HSIC, there are some special requirement:
- The HSIC pad is 1.2v, it may need to supply from external
- The data/strobe pin needs to be pulled down first, and after
  host mode is initialized, the strobe pin needs to be pulled up
- During the USB suspend/resume, special setting is needed

Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/chipidea/ci_hdrc_imx.c | 140 ++++++++++++++++++++++++++++++++-----
 drivers/usb/chipidea/ci_hdrc_imx.h |   9 ++-
 drivers/usb/chipidea/usbmisc_imx.c | 140 +++++++++++++++++++++++++++++++++++++
 3 files changed, 270 insertions(+), 19 deletions(-)

diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c b/drivers/usb/chipidea/ci_hdrc_imx.c
index 09b37c0d075d..56781c329db0 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.c
+++ b/drivers/usb/chipidea/ci_hdrc_imx.c
@@ -14,6 +14,7 @@
 #include <linux/usb/chipidea.h>
 #include <linux/usb/of.h>
 #include <linux/clk.h>
+#include <linux/pinctrl/consumer.h>
 
 #include "ci.h"
 #include "ci_hdrc_imx.h"
@@ -85,6 +86,9 @@ struct ci_hdrc_imx_data {
 	bool supports_runtime_pm;
 	bool override_phy_control;
 	bool in_lpm;
+	struct pinctrl *pinctrl;
+	struct pinctrl_state *pinctrl_hsic_active;
+	struct regulator *hsic_pad_regulator;
 	/* SoC before i.mx6 (except imx23/imx28) needs three clks */
 	bool need_three_clks;
 	struct clk *clk_ipg;
@@ -245,19 +249,49 @@ static void imx_disable_unprepare_clks(struct device *dev)
 	}
 }
 
+static int ci_hdrc_imx_notify_event(struct ci_hdrc *ci, unsigned int event)
+{
+	struct device *dev = ci->dev->parent;
+	struct ci_hdrc_imx_data *data = dev_get_drvdata(dev);
+	int ret = 0;
+
+	switch (event) {
+	case CI_HDRC_IMX_HSIC_ACTIVE_EVENT:
+		ret = pinctrl_select_state(data->pinctrl,
+				data->pinctrl_hsic_active);
+		if (ret)
+			dev_err(dev, "hsic_active select failed, err=%d\n",
+				ret);
+		break;
+	case CI_HDRC_IMX_HSIC_SUSPEND_EVENT:
+		ret = imx_usbmisc_hsic_set_connect(data->usbmisc_data);
+		if (ret)
+			dev_err(dev,
+				"hsic_set_connect failed, err=%d\n", ret);
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
 static int ci_hdrc_imx_probe(struct platform_device *pdev)
 {
 	struct ci_hdrc_imx_data *data;
 	struct ci_hdrc_platform_data pdata = {
 		.name		= dev_name(&pdev->dev),
 		.capoffset	= DEF_CAPOFFSET,
+		.notify_event	= ci_hdrc_imx_notify_event,
 	};
 	int ret;
 	const struct of_device_id *of_id;
 	const struct ci_hdrc_imx_platform_flag *imx_platform_flag;
 	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct pinctrl_state *pinctrl_hsic_idle;
 
-	of_id = of_match_device(ci_hdrc_imx_dt_ids, &pdev->dev);
+	of_id = of_match_device(ci_hdrc_imx_dt_ids, dev);
 	if (!of_id)
 		return -ENODEV;
 
@@ -268,19 +302,73 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	platform_set_drvdata(pdev, data);
-	data->usbmisc_data = usbmisc_get_init_data(&pdev->dev);
+	data->usbmisc_data = usbmisc_get_init_data(dev);
 	if (IS_ERR(data->usbmisc_data))
 		return PTR_ERR(data->usbmisc_data);
 
-	ret = imx_get_clks(&pdev->dev);
+	if (of_usb_get_phy_mode(dev->of_node) == USBPHY_INTERFACE_MODE_HSIC) {
+		pdata.flags |= CI_HDRC_IMX_IS_HSIC;
+		data->usbmisc_data->hsic = 1;
+		data->pinctrl = devm_pinctrl_get(dev);
+		if (IS_ERR(data->pinctrl)) {
+			dev_err(dev, "pinctrl get failed, err=%ld\n",
+					PTR_ERR(data->pinctrl));
+			return PTR_ERR(data->pinctrl);
+		}
+
+		pinctrl_hsic_idle = pinctrl_lookup_state(data->pinctrl, "idle");
+		if (IS_ERR(pinctrl_hsic_idle)) {
+			dev_err(dev,
+				"pinctrl_hsic_idle lookup failed, err=%ld\n",
+					PTR_ERR(pinctrl_hsic_idle));
+			return PTR_ERR(pinctrl_hsic_idle);
+		}
+
+		ret = pinctrl_select_state(data->pinctrl, pinctrl_hsic_idle);
+		if (ret) {
+			dev_err(dev, "hsic_idle select failed, err=%d\n", ret);
+			return ret;
+		}
+
+		data->pinctrl_hsic_active = pinctrl_lookup_state(data->pinctrl,
+								"active");
+		if (IS_ERR(data->pinctrl_hsic_active)) {
+			dev_err(dev,
+				"pinctrl_hsic_active lookup failed, err=%ld\n",
+					PTR_ERR(data->pinctrl_hsic_active));
+			return PTR_ERR(data->pinctrl_hsic_active);
+		}
+
+		data->hsic_pad_regulator = devm_regulator_get(dev, "hsic");
+		if (PTR_ERR(data->hsic_pad_regulator) == -EPROBE_DEFER) {
+			return -EPROBE_DEFER;
+		} else if (PTR_ERR(data->hsic_pad_regulator) == -ENODEV) {
+			/* no pad regualator is needed */
+			data->hsic_pad_regulator = NULL;
+		} else if (IS_ERR(data->hsic_pad_regulator)) {
+			dev_err(dev, "Get HSIC pad regulator error: %ld\n",
+					PTR_ERR(data->hsic_pad_regulator));
+			return PTR_ERR(data->hsic_pad_regulator);
+		}
+
+		if (data->hsic_pad_regulator) {
+			ret = regulator_enable(data->hsic_pad_regulator);
+			if (ret) {
+				dev_err(dev,
+					"Failed to enable HSIC pad regulator\n");
+				return ret;
+			}
+		}
+	}
+	ret = imx_get_clks(dev);
 	if (ret)
-		return ret;
+		goto disable_hsic_regulator;
 
-	ret = imx_prepare_enable_clks(&pdev->dev);
+	ret = imx_prepare_enable_clks(dev);
 	if (ret)
-		return ret;
+		goto disable_hsic_regulator;
 
-	data->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "fsl,usbphy", 0);
+	data->phy = devm_usb_get_phy_by_phandle(dev, "fsl,usbphy", 0);
 	if (IS_ERR(data->phy)) {
 		ret = PTR_ERR(data->phy);
 		/* Return -EINVAL if no usbphy is available */
@@ -305,40 +393,43 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev)
 
 	ret = imx_usbmisc_init(data->usbmisc_data);
 	if (ret) {
-		dev_err(&pdev->dev, "usbmisc init failed, ret=%d\n", ret);
+		dev_err(dev, "usbmisc init failed, ret=%d\n", ret);
 		goto err_clk;
 	}
 
-	data->ci_pdev = ci_hdrc_add_device(&pdev->dev,
+	data->ci_pdev = ci_hdrc_add_device(dev,
 				pdev->resource, pdev->num_resources,
 				&pdata);
 	if (IS_ERR(data->ci_pdev)) {
 		ret = PTR_ERR(data->ci_pdev);
 		if (ret != -EPROBE_DEFER)
-			dev_err(&pdev->dev,
-				"ci_hdrc_add_device failed, err=%d\n", ret);
+			dev_err(dev, "ci_hdrc_add_device failed, err=%d\n",
+					ret);
 		goto err_clk;
 	}
 
 	ret = imx_usbmisc_init_post(data->usbmisc_data);
 	if (ret) {
-		dev_err(&pdev->dev, "usbmisc post failed, ret=%d\n", ret);
+		dev_err(dev, "usbmisc post failed, ret=%d\n", ret);
 		goto disable_device;
 	}
 
 	if (data->supports_runtime_pm) {
-		pm_runtime_set_active(&pdev->dev);
-		pm_runtime_enable(&pdev->dev);
+		pm_runtime_set_active(dev);
+		pm_runtime_enable(dev);
 	}
 
-	device_set_wakeup_capable(&pdev->dev, true);
+	device_set_wakeup_capable(dev, true);
 
 	return 0;
 
 disable_device:
 	ci_hdrc_remove_device(data->ci_pdev);
 err_clk:
-	imx_disable_unprepare_clks(&pdev->dev);
+	imx_disable_unprepare_clks(dev);
+disable_hsic_regulator:
+	if (data->hsic_pad_regulator)
+		ret = regulator_disable(data->hsic_pad_regulator);
 	return ret;
 }
 
@@ -355,6 +446,8 @@ static int ci_hdrc_imx_remove(struct platform_device *pdev)
 	if (data->override_phy_control)
 		usb_phy_shutdown(data->phy);
 	imx_disable_unprepare_clks(&pdev->dev);
+	if (data->hsic_pad_regulator)
+		regulator_disable(data->hsic_pad_regulator);
 
 	return 0;
 }
@@ -367,9 +460,16 @@ static void ci_hdrc_imx_shutdown(struct platform_device *pdev)
 static int __maybe_unused imx_controller_suspend(struct device *dev)
 {
 	struct ci_hdrc_imx_data *data = dev_get_drvdata(dev);
+	int ret = 0;
 
 	dev_dbg(dev, "at %s\n", __func__);
 
+	ret = imx_usbmisc_hsic_set_clk(data->usbmisc_data, false);
+	if (ret) {
+		dev_err(dev, "usbmisc hsic_set_clk failed, ret=%d\n", ret);
+		return ret;
+	}
+
 	imx_disable_unprepare_clks(dev);
 	data->in_lpm = true;
 
@@ -400,8 +500,16 @@ static int __maybe_unused imx_controller_resume(struct device *dev)
 		goto clk_disable;
 	}
 
+	ret = imx_usbmisc_hsic_set_clk(data->usbmisc_data, true);
+	if (ret) {
+		dev_err(dev, "usbmisc hsic_set_clk failed, ret=%d\n", ret);
+		goto hsic_set_clk_fail;
+	}
+
 	return 0;
 
+hsic_set_clk_fail:
+	imx_usbmisc_set_wakeup(data->usbmisc_data, true);
 clk_disable:
 	imx_disable_unprepare_clks(dev);
 	return ret;
diff --git a/drivers/usb/chipidea/ci_hdrc_imx.h b/drivers/usb/chipidea/ci_hdrc_imx.h
index 204275f47573..fcecab478934 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.h
+++ b/drivers/usb/chipidea/ci_hdrc_imx.h
@@ -14,10 +14,13 @@ struct imx_usbmisc_data {
 	unsigned int oc_polarity:1; /* over current polarity if oc enabled */
 	unsigned int evdo:1; /* set external vbus divider option */
 	unsigned int ulpi:1; /* connected to an ULPI phy */
+	unsigned int hsic:1; /* HSIC controlller */
 };
 
-int imx_usbmisc_init(struct imx_usbmisc_data *);
-int imx_usbmisc_init_post(struct imx_usbmisc_data *);
-int imx_usbmisc_set_wakeup(struct imx_usbmisc_data *, bool);
+int imx_usbmisc_init(struct imx_usbmisc_data *data);
+int imx_usbmisc_init_post(struct imx_usbmisc_data *data);
+int imx_usbmisc_set_wakeup(struct imx_usbmisc_data *data, bool enabled);
+int imx_usbmisc_hsic_set_connect(struct imx_usbmisc_data *data);
+int imx_usbmisc_hsic_set_clk(struct imx_usbmisc_data *data, bool on);
 
 #endif /* __DRIVER_USB_CHIPIDEA_CI_HDRC_IMX_H */
diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index def80ff547e4..43a15a6e86f5 100644
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -64,10 +64,22 @@
 #define MX6_BM_OVER_CUR_DIS		BIT(7)
 #define MX6_BM_OVER_CUR_POLARITY	BIT(8)
 #define MX6_BM_WAKEUP_ENABLE		BIT(10)
+#define MX6_BM_UTMI_ON_CLOCK		BIT(13)
 #define MX6_BM_ID_WAKEUP		BIT(16)
 #define MX6_BM_VBUS_WAKEUP		BIT(17)
 #define MX6SX_BM_DPDM_WAKEUP_EN		BIT(29)
 #define MX6_BM_WAKEUP_INTR		BIT(31)
+
+#define MX6_USB_HSIC_CTRL_OFFSET	0x10
+/* Send resume signal without 480Mhz PHY clock */
+#define MX6SX_BM_HSIC_AUTO_RESUME	BIT(23)
+/* set before portsc.suspendM = 1 */
+#define MX6_BM_HSIC_DEV_CONN		BIT(21)
+/* HSIC enable */
+#define MX6_BM_HSIC_EN			BIT(12)
+/* Force HSIC module 480M clock on, even when in Host is in suspend mode */
+#define MX6_BM_HSIC_CLK_ON		BIT(11)
+
 #define MX6_USB_OTG1_PHY_CTRL		0x18
 /* For imx6dql, it is host-only controller, for later imx6, it is otg's */
 #define MX6_USB_OTG2_PHY_CTRL		0x1c
@@ -94,6 +106,10 @@ struct usbmisc_ops {
 	int (*post)(struct imx_usbmisc_data *data);
 	/* It's called when we need to enable/disable usb wakeup */
 	int (*set_wakeup)(struct imx_usbmisc_data *data, bool enabled);
+	/* It's called before setting portsc.suspendM */
+	int (*hsic_set_connect)(struct imx_usbmisc_data *data);
+	/* It's called during suspend/resume */
+	int (*hsic_set_clk)(struct imx_usbmisc_data *data, bool enabled);
 };
 
 struct imx_usbmisc {
@@ -353,6 +369,18 @@ static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
 	writel(reg | MX6_BM_NON_BURST_SETTING,
 			usbmisc->base + data->index * 4);
 
+	/* For HSIC controller */
+	if (data->hsic) {
+		reg = readl(usbmisc->base + data->index * 4);
+		writel(reg | MX6_BM_UTMI_ON_CLOCK,
+			usbmisc->base + data->index * 4);
+		reg = readl(usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET
+			+ (data->index - 2) * 4);
+		reg |= MX6_BM_HSIC_EN | MX6_BM_HSIC_CLK_ON;
+		writel(reg, usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET
+			+ (data->index - 2) * 4);
+	}
+
 	spin_unlock_irqrestore(&usbmisc->lock, flags);
 
 	usbmisc_imx6q_set_wakeup(data, false);
@@ -360,6 +388,79 @@ static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
 	return 0;
 }
 
+static int usbmisc_imx6_hsic_get_reg_offset(struct imx_usbmisc_data *data)
+{
+	int offset, ret = 0;
+
+	if (data->index == 2 || data->index == 3) {
+		offset = (data->index - 2) * 4;
+	} else if (data->index == 0) {
+		/*
+		 * For SoCs like i.MX7D and later, each USB controller has
+		 * its own non-core register region. For SoCs before i.MX7D,
+		 * the first two USB controllers are non-HSIC controllers.
+		 */
+		offset = 0;
+	} else {
+		dev_err(data->dev, "index is error for usbmisc\n");
+		ret = -EINVAL;
+	}
+
+	return ret ? ret : offset;
+}
+
+static int usbmisc_imx6_hsic_set_connect(struct imx_usbmisc_data *data)
+{
+	unsigned long flags;
+	u32 val;
+	struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
+	int offset;
+
+	spin_lock_irqsave(&usbmisc->lock, flags);
+	offset = usbmisc_imx6_hsic_get_reg_offset(data);
+	if (offset < 0) {
+		spin_unlock_irqrestore(&usbmisc->lock, flags);
+		return offset;
+	}
+
+	val = readl(usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET + offset);
+	if (!(val & MX6_BM_HSIC_DEV_CONN))
+		writel(val | MX6_BM_HSIC_DEV_CONN,
+			usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET + offset);
+
+	spin_unlock_irqrestore(&usbmisc->lock, flags);
+
+	return 0;
+}
+
+static int usbmisc_imx6_hsic_set_clk(struct imx_usbmisc_data *data, bool on)
+{
+	unsigned long flags;
+	u32 val;
+	struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
+	int offset;
+
+	spin_lock_irqsave(&usbmisc->lock, flags);
+	offset = usbmisc_imx6_hsic_get_reg_offset(data);
+	if (offset < 0) {
+		spin_unlock_irqrestore(&usbmisc->lock, flags);
+		return offset;
+	}
+
+	val = readl(usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET + offset);
+	val |= MX6_BM_HSIC_EN | MX6_BM_HSIC_CLK_ON;
+	if (on)
+		val |= MX6_BM_HSIC_CLK_ON;
+	else
+		val &= ~MX6_BM_HSIC_CLK_ON;
+
+	writel(val, usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET + offset);
+	spin_unlock_irqrestore(&usbmisc->lock, flags);
+
+	return 0;
+}
+
+
 static int usbmisc_imx6sx_init(struct imx_usbmisc_data *data)
 {
 	void __iomem *reg = NULL;
@@ -385,6 +486,13 @@ static int usbmisc_imx6sx_init(struct imx_usbmisc_data *data)
 		spin_unlock_irqrestore(&usbmisc->lock, flags);
 	}
 
+	/* For HSIC controller */
+	if (data->hsic) {
+		val = readl(usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET);
+		val |= MX6SX_BM_HSIC_AUTO_RESUME;
+		writel(val, usbmisc->base + MX6_USB_HSIC_CTRL_OFFSET);
+	}
+
 	return 0;
 }
 
@@ -454,6 +562,7 @@ static int usbmisc_imx7d_init(struct imx_usbmisc_data *data)
 	reg &= ~MX7D_USB_VBUS_WAKEUP_SOURCE_MASK;
 	writel(reg | MX7D_USB_VBUS_WAKEUP_SOURCE_BVALID,
 		 usbmisc->base + MX7D_USBNC_USB_CTRL2);
+
 	spin_unlock_irqrestore(&usbmisc->lock, flags);
 
 	usbmisc_imx7d_set_wakeup(data, false);
@@ -481,6 +590,8 @@ static const struct usbmisc_ops imx53_usbmisc_ops = {
 static const struct usbmisc_ops imx6q_usbmisc_ops = {
 	.set_wakeup = usbmisc_imx6q_set_wakeup,
 	.init = usbmisc_imx6q_init,
+	.hsic_set_connect = usbmisc_imx6_hsic_set_connect,
+	.hsic_set_clk   = usbmisc_imx6_hsic_set_clk,
 };
 
 static const struct usbmisc_ops vf610_usbmisc_ops = {
@@ -490,6 +601,8 @@ static const struct usbmisc_ops vf610_usbmisc_ops = {
 static const struct usbmisc_ops imx6sx_usbmisc_ops = {
 	.set_wakeup = usbmisc_imx6q_set_wakeup,
 	.init = usbmisc_imx6sx_init,
+	.hsic_set_connect = usbmisc_imx6_hsic_set_connect,
+	.hsic_set_clk = usbmisc_imx6_hsic_set_clk,
 };
 
 static const struct usbmisc_ops imx7d_usbmisc_ops = {
@@ -546,6 +659,33 @@ int imx_usbmisc_set_wakeup(struct imx_usbmisc_data *data, bool enabled)
 }
 EXPORT_SYMBOL_GPL(imx_usbmisc_set_wakeup);
 
+int imx_usbmisc_hsic_set_connect(struct imx_usbmisc_data *data)
+{
+	struct imx_usbmisc *usbmisc;
+
+	if (!data)
+		return 0;
+
+	usbmisc = dev_get_drvdata(data->dev);
+	if (!usbmisc->ops->hsic_set_connect || !data->hsic)
+		return 0;
+	return usbmisc->ops->hsic_set_connect(data);
+}
+EXPORT_SYMBOL_GPL(imx_usbmisc_hsic_set_connect);
+
+int imx_usbmisc_hsic_set_clk(struct imx_usbmisc_data *data, bool on)
+{
+	struct imx_usbmisc *usbmisc;
+
+	if (!data)
+		return 0;
+
+	usbmisc = dev_get_drvdata(data->dev);
+	if (!usbmisc->ops->hsic_set_clk || !data->hsic)
+		return 0;
+	return usbmisc->ops->hsic_set_clk(data, on);
+}
+EXPORT_SYMBOL_GPL(imx_usbmisc_hsic_set_clk);
 static const struct of_device_id usbmisc_imx_dt_ids[] = {
 	{
 		.compatible = "fsl,imx25-usbmisc",

             reply	other threads:[~2018-12-11  2:08 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-11  2:08 Peter Chen [this message]
2019-09-13  9:47 ` [v5,2/4] usb: chipidea: imx: add HSIC support André Draszik
2019-09-16  2:31   ` Peter Chen

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