[PATCH v2 1/2] usb: phy: add a new driver for usb3 phy

Kishon Vijay Abraham I kishon at ti.com
Fri Sep 28 00:04:07 EST 2012


Added a driver for usb3 phy that handles the interaction between usb phy
device and dwc3 controller.

This also includes device tree support for usb3 phy driver and
the documentation with device tree binding information is updated.

Currently writing to control module register is taken care in this
driver which will be removed once the control module driver is in place.

Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
Signed-off-by: Felipe Balbi <balbi at ti.com>
Signed-off-by: Moiz Sonasath <m-sonasath at ti.com>
---
 Documentation/devicetree/bindings/usb/usb-phy.txt |   18 +
 drivers/usb/phy/Kconfig                           |    9 +
 drivers/usb/phy/Makefile                          |    1 +
 drivers/usb/phy/omap-usb3.c                       |  412 +++++++++++++++++++++
 include/linux/usb/omap_usb.h                      |   33 ++
 5 files changed, 473 insertions(+)
 create mode 100644 drivers/usb/phy/omap-usb3.c

diff --git a/Documentation/devicetree/bindings/usb/usb-phy.txt b/Documentation/devicetree/bindings/usb/usb-phy.txt
index 80d4148..7c5fd89 100644
--- a/Documentation/devicetree/bindings/usb/usb-phy.txt
+++ b/Documentation/devicetree/bindings/usb/usb-phy.txt
@@ -15,3 +15,21 @@ usb2phy at 4a0ad080 {
 	reg = <0x4a0ad080 0x58>,
 	      <0x4a002300 0x4>;
 };
+
+OMAP USB3 PHY
+
+Required properties:
+ - compatible: Should be "ti,omap-usb3"
+ - reg : Address and length of the register set for the device. Also
+add the address of control module phy power register until a driver for
+control module is added
+
+This is usually a subnode of ocp2scp to which it is connected.
+
+usb3phy at 4a084400 {
+	compatible = "ti,omap-usb3";
+	reg = <0x0x4a084400 0x80>,
+	      <0x4a084800 0x64>,
+	      <0x4a084c00 0x40>,
+	      <0x4a002370 0x4>;
+};
diff --git a/drivers/usb/phy/Kconfig b/drivers/usb/phy/Kconfig
index 63c339b..353dc0c 100644
--- a/drivers/usb/phy/Kconfig
+++ b/drivers/usb/phy/Kconfig
@@ -13,6 +13,15 @@ config OMAP_USB2
 	  The USB OTG controller communicates with the comparator using this
 	  driver.
 
+config OMAP_USB3
+	tristate "OMAP USB3 PHY Driver"
+	select USB_OTG_UTILS
+	help
+	  Enable this to support the USB3 PHY that is part of SOC. This
+	  driver takes care of all the PHY functionality apart from comparator.
+	  The USB OTG controller communicates with the comparator using this
+	  driver.
+
 config USB_ISP1301
 	tristate "NXP ISP1301 USB transceiver support"
 	depends on USB || USB_GADGET
diff --git a/drivers/usb/phy/Makefile b/drivers/usb/phy/Makefile
index b069f29..973b1e6 100644
--- a/drivers/usb/phy/Makefile
+++ b/drivers/usb/phy/Makefile
@@ -5,6 +5,7 @@
 ccflags-$(CONFIG_USB_DEBUG) := -DDEBUG
 
 obj-$(CONFIG_OMAP_USB2)			+= omap-usb2.o
+obj-$(CONFIG_OMAP_USB3)			+= omap-usb3.o
 obj-$(CONFIG_USB_ISP1301)		+= isp1301.o
 obj-$(CONFIG_MV_U3D_PHY)		+= mv_u3d_phy.o
 obj-$(CONFIG_USB_EHCI_TEGRA)	+= tegra_usb_phy.o
diff --git a/drivers/usb/phy/omap-usb3.c b/drivers/usb/phy/omap-usb3.c
new file mode 100644
index 0000000..cecfbd4
--- /dev/null
+++ b/drivers/usb/phy/omap-usb3.c
@@ -0,0 +1,412 @@
+/*
+ * omap-usb3 - USB PHY, talking to dwc3 controller in OMAP.
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Author: Kishon Vijay Abraham I <kishon at ti.com>
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/usb/omap_usb.h>
+#include <linux/of.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/pm_runtime.h>
+#include <linux/delay.h>
+
+#define	NUM_SYS_CLKS		5
+#define	PLL_STATUS		0x00000004
+#define	PLL_GO			0x00000008
+#define	PLL_CONFIGURATION1	0x0000000C
+#define	PLL_CONFIGURATION2	0x00000010
+#define	PLL_CONFIGURATION3	0x00000014
+#define	PLL_CONFIGURATION4	0x00000020
+
+#define	PLL_REGM_MASK		0x001FFE00
+#define	PLL_REGM_SHIFT		0x9
+#define	PLL_REGM_F_MASK		0x0003FFFF
+#define	PLL_REGM_F_SHIFT	0x0
+#define	PLL_REGN_MASK		0x000001FE
+#define	PLL_REGN_SHIFT		0x1
+#define	PLL_SELFREQDCO_MASK	0x0000000E
+#define	PLL_SELFREQDCO_SHIFT	0x1
+#define	PLL_SD_MASK		0x0003FC00
+#define	PLL_SD_SHIFT		0x9
+#define	SET_PLL_GO		0x1
+#define	PLL_TICOPWDN		0x10000
+#define	PLL_LOCK		0x2
+#define	PLL_IDLE		0x1
+
+/*
+ * This is an Empirical value that works, need to confirm the actual
+ * value required for the USB3PHY_PLL_CONFIGURATION2.PLL_IDLE status
+ * to be correctly reflected in the USB3PHY_PLL_STATUS register.
+ */
+# define PLL_IDLE_TIME  100;
+
+enum sys_clk_rate {
+	CLK_RATE_UNDEFINED = -1,
+	CLK_RATE_12MHZ,
+	CLK_RATE_16MHZ,
+	CLK_RATE_19MHZ,
+	CLK_RATE_26MHZ,
+	CLK_RATE_38MHZ
+};
+
+static struct usb_dpll_params omap_usb3_dpll_params[NUM_SYS_CLKS] = {
+	{1250, 5, 4, 20, 0},		/* 12 MHz */
+	{3125, 20, 4, 20, 0},		/* 16.8 MHz */
+	{1172, 8, 4, 20, 65537},	/* 19.2 MHz */
+	{1250, 12, 4, 20, 0},		/* 26 MHz */
+	{3125, 47, 4, 20, 92843},	/* 38.4 MHz */
+};
+
+/**
+ * omap5_usb_phy_power - power on/off the serializer using control module
+ * @phy: struct omap_usb *
+ * @on: 0 to off and 1 to on based on powering on or off the PHY
+ *
+ * omap_usb3 can call this API to power on or off the PHY.
+ *
+ * XXX: Remove this function once control module driver gets merged
+ */
+static int omap5_usb_phy_power(struct omap_usb *phy, bool on)
+{
+	u32 val;
+	unsigned long rate;
+	struct clk *sys_clk;
+
+	sys_clk = clk_get(NULL, "sys_clkin");
+	if (IS_ERR(sys_clk)) {
+		pr_err("%s: unable to get sys_clkin\n", __func__);
+		return -EINVAL;
+	}
+
+	rate = clk_get_rate(sys_clk);
+	rate = rate/1000000;
+	clk_put(sys_clk);
+
+	val = readl(phy->control_dev);
+
+	if (on) {
+		val &= ~(USB_PWRCTL_CLK_CMD_MASK | USB_PWRCTL_CLK_FREQ_MASK);
+		val |= USB3_PHY_TX_RX_POWERON << USB_PWRCTL_CLK_CMD_SHIFT;
+		val |= rate << USB_PWRCTL_CLK_FREQ_SHIFT;
+	} else {
+		val &= ~USB_PWRCTL_CLK_CMD_MASK;
+		val |= USB3_PHY_TX_RX_POWEROFF << USB_PWRCTL_CLK_CMD_SHIFT;
+	}
+
+	writel(val, phy->control_dev);
+
+	return 0;
+}
+
+static int omap_usb3_suspend(struct usb_phy *x, int suspend)
+{
+	struct omap_usb *phy = phy_to_omapusb(x);
+	int	val, ret;
+	int timeout = PLL_IDLE_TIME;
+
+	if (suspend && !phy->is_suspended) {
+		val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
+		val |= PLL_IDLE;
+		omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
+
+		do {
+			val = omap_usb_readl(phy->pll_ctrl_base, PLL_STATUS);
+			if (val & PLL_TICOPWDN)
+				break;
+			udelay(1);
+		} while (--timeout);
+
+		omap5_usb_phy_power(phy, 0);
+		pm_runtime_put_sync(phy->dev);
+
+		phy->is_suspended	= 1;
+	} else if (!suspend && phy->is_suspended) {
+		phy->is_suspended	= 0;
+		ret = pm_runtime_get_sync(phy->dev);
+		if (ret < 0) {
+			dev_err(phy->dev, "get_sync failed with err %d\n",
+									ret);
+			return ret;
+		}
+
+		val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
+		val &= ~PLL_IDLE;
+		omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
+
+		do {
+			val = omap_usb_readl(phy->pll_ctrl_base, PLL_STATUS);
+			if (!(val & PLL_TICOPWDN))
+				break;
+			udelay(1);
+		} while (--timeout);
+	}
+
+	return 0;
+}
+
+static inline enum sys_clk_rate __get_sys_clk_index(unsigned long rate)
+{
+	switch (rate) {
+	case 12000000:
+		return CLK_RATE_12MHZ;
+	case 16800000:
+		return CLK_RATE_16MHZ;
+	case 19200000:
+		return CLK_RATE_19MHZ;
+	case 26000000:
+		return CLK_RATE_26MHZ;
+	case 38400000:
+		return CLK_RATE_38MHZ;
+	default:
+		return CLK_RATE_UNDEFINED;
+	}
+}
+
+static void omap_usb_dpll_relock(struct omap_usb *phy)
+{
+	u32		val;
+	unsigned long	timeout;
+
+	omap_usb_writel(phy->pll_ctrl_base, PLL_GO, SET_PLL_GO);
+
+	timeout = jiffies + msecs_to_jiffies(20);
+	do {
+		val = omap_usb_readl(phy->pll_ctrl_base, PLL_STATUS);
+		if (val & PLL_LOCK)
+			break;
+	} while (!WARN_ON(time_after(jiffies, timeout)));
+}
+
+static int omap_usb_dpll_lock(struct omap_usb *phy)
+{
+	u32			val;
+	struct clk		*sys_clk;
+	unsigned long		rate;
+	enum sys_clk_rate	clk_index;
+
+	sys_clk	= clk_get(NULL, "sys_clkin");
+	if (IS_ERR(sys_clk)) {
+		pr_err("unable to get sys_clkin\n");
+		return PTR_ERR(sys_clk);
+	}
+
+	rate		= clk_get_rate(sys_clk);
+	clk_index	= __get_sys_clk_index(rate);
+
+	if (clk_index == CLK_RATE_UNDEFINED) {
+		pr_err("dpll cannot be locked for sys clk freq:%luHz\n", rate);
+		return -EINVAL;
+	}
+	clk_put(sys_clk);
+
+	val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
+	val &= ~PLL_REGN_MASK;
+	val |= omap_usb3_dpll_params[clk_index].n << PLL_REGN_SHIFT;
+	omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
+
+	val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
+	val &= ~PLL_SELFREQDCO_MASK;
+	val |= omap_usb3_dpll_params[clk_index].freq << PLL_SELFREQDCO_SHIFT;
+	omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
+
+	val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
+	val &= ~PLL_REGM_MASK;
+	val |= omap_usb3_dpll_params[clk_index].m << PLL_REGM_SHIFT;
+	omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
+
+	val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION4);
+	val &= ~PLL_REGM_F_MASK;
+	val |= omap_usb3_dpll_params[clk_index].mf << PLL_REGM_F_SHIFT;
+	omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION4, val);
+
+	val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION3);
+	val &= ~PLL_SD_MASK;
+	val |= omap_usb3_dpll_params[clk_index].sd << PLL_SD_SHIFT;
+	omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION3, val);
+
+	omap_usb_dpll_relock(phy);
+
+	return 0;
+}
+
+static int omap_usb3_init(struct usb_phy *x)
+{
+	struct omap_usb	*phy = phy_to_omapusb(x);
+
+	omap_usb_dpll_lock(phy);
+	omap5_usb_phy_power(phy, 1);
+
+	return 0;
+}
+
+static int __devinit omap_usb3_probe(struct platform_device *pdev)
+{
+	struct omap_usb			*phy;
+	struct resource			*res;
+
+	phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
+	if (!phy) {
+		dev_err(&pdev->dev, "unable to alloc mem for OMAP USB3 PHY\n");
+		return -ENOMEM;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (!res) {
+		dev_err(&pdev->dev, "unable to get base address of pll_ctrl\n");
+		return -ENODEV;
+	}
+
+	phy->pll_ctrl_base = devm_request_and_ioremap(&pdev->dev, res);
+	if (!phy->pll_ctrl_base) {
+		dev_err(&pdev->dev, "ioremap of pll_ctrl failed\n");
+		return -ENOMEM;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+	if (!res) {
+		dev_err(&pdev->dev,
+			"unable to get address of control phy power\n");
+		return -ENODEV;
+	}
+
+	phy->control_dev = devm_request_and_ioremap(&pdev->dev, res);
+	if (!phy->control_dev) {
+		dev_err(&pdev->dev, "ioremap of control_dev failed\n");
+		return -ENOMEM;
+	}
+
+	phy->dev		= &pdev->dev;
+
+	phy->phy.dev		= phy->dev;
+	phy->phy.label		= "omap-usb3";
+	phy->phy.init		= omap_usb3_init;
+	phy->phy.set_suspend	= omap_usb3_suspend;
+
+	phy->is_suspended	= 1;
+	omap5_usb_phy_power(phy, 0);
+
+	phy->wkupclk = devm_clk_get(phy->dev, "usb_phy_cm_clk32k");
+	if (IS_ERR(phy->wkupclk)) {
+		dev_err(&pdev->dev, "unable to get usb_phy_cm_clk32k\n");
+		return PTR_ERR(phy->wkupclk);
+	}
+	clk_prepare(phy->wkupclk);
+
+	phy->optclk = devm_clk_get(phy->dev, "usb_otg_ss_refclk960m");
+	if (IS_ERR(phy->optclk)) {
+		dev_err(&pdev->dev, "unable to get usb_otg_ss_refclk960m\n");
+		return PTR_ERR(phy->optclk);
+	}
+	clk_prepare(phy->optclk);
+
+	usb_add_phy(&phy->phy, USB_PHY_TYPE_USB3);
+
+	platform_set_drvdata(pdev, phy);
+
+	pm_runtime_enable(phy->dev);
+
+	return 0;
+}
+
+static int __devexit omap_usb3_remove(struct platform_device *pdev)
+{
+	struct omap_usb *phy = platform_get_drvdata(pdev);
+
+	clk_unprepare(phy->wkupclk);
+	clk_unprepare(phy->optclk);
+	usb_remove_phy(&phy->phy);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_RUNTIME
+
+static int omap_usb3_runtime_suspend(struct device *dev)
+{
+	struct platform_device	*pdev = to_platform_device(dev);
+	struct omap_usb	*phy = platform_get_drvdata(pdev);
+
+	clk_disable(phy->wkupclk);
+	clk_disable(phy->optclk);
+
+	return 0;
+}
+
+static int omap_usb3_runtime_resume(struct device *dev)
+{
+	u32 ret = 0;
+	struct platform_device	*pdev = to_platform_device(dev);
+	struct omap_usb	*phy = platform_get_drvdata(pdev);
+
+	ret = clk_enable(phy->optclk);
+	if (ret) {
+		dev_err(phy->dev, "Failed to enable optclk %d\n", ret);
+		goto err1;
+	}
+
+	ret = clk_enable(phy->wkupclk);
+	if (ret) {
+		dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
+		goto err2;
+	}
+
+	return 0;
+
+err2:
+	clk_disable(phy->optclk);
+
+err1:
+	return ret;
+}
+
+static const struct dev_pm_ops omap_usb3_pm_ops = {
+	SET_RUNTIME_PM_OPS(omap_usb3_runtime_suspend, omap_usb3_runtime_resume,
+		NULL)
+};
+
+#define DEV_PM_OPS     (&omap_usb3_pm_ops)
+#else
+#define DEV_PM_OPS     NULL
+#endif
+
+#ifdef CONFIG_OF
+static const struct of_device_id omap_usb3_id_table[] = {
+	{ .compatible = "ti,omap-usb3" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, omap_usb3_id_table);
+#endif
+
+static struct platform_driver omap_usb3_driver = {
+	.probe		= omap_usb3_probe,
+	.remove		= __devexit_p(omap_usb3_remove),
+	.driver		= {
+		.name	= "omap-usb3",
+		.owner	= THIS_MODULE,
+		.pm	= DEV_PM_OPS,
+		.of_match_table = of_match_ptr(omap_usb3_id_table),
+	},
+};
+
+module_platform_driver(omap_usb3_driver);
+
+MODULE_ALIAS("platform: omap_usb3");
+MODULE_AUTHOR("Texas Instruments Inc.");
+MODULE_DESCRIPTION("OMAP USB3 phy driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/usb/omap_usb.h b/include/linux/usb/omap_usb.h
index 0ea17f8..6947528 100644
--- a/include/linux/usb/omap_usb.h
+++ b/include/linux/usb/omap_usb.h
@@ -19,19 +19,41 @@
 #ifndef __DRIVERS_OMAP_USB2_H
 #define __DRIVERS_OMAP_USB2_H
 
+#include <linux/io.h>
 #include <linux/usb/otg.h>
 
+struct usb_dpll_params {
+	u16	m;
+	u8	n;
+	u8	freq:3;
+	u8	sd;
+	u32	mf;
+};
+
 struct omap_usb {
 	struct usb_phy		phy;
 	struct phy_companion	*comparator;
+	void __iomem		*pll_ctrl_base;
 	struct device		*dev;
 	u32 __iomem		*control_dev;
 	struct clk		*wkupclk;
+	struct clk		*optclk;
 	u8			is_suspended:1;
 };
 
 #define	PHY_PD	0x1
 
+#define	CONTROL_PHY_POWER_USB		0x00000370
+
+#define	USB_PWRCTL_CLK_CMD_MASK		0x003FC000
+#define	USB_PWRCTL_CLK_CMD_SHIFT	0xE
+
+#define	USB_PWRCTL_CLK_FREQ_MASK	0xFFC00000
+#define	USB_PWRCTL_CLK_FREQ_SHIFT	0x16
+
+#define	USB3_PHY_TX_RX_POWERON		0x3
+#define	USB3_PHY_TX_RX_POWEROFF		0x0
+
 #define	phy_to_omapusb(x)	container_of((x), struct omap_usb, phy)
 
 #if defined(CONFIG_OMAP_USB2) || defined(CONFIG_OMAP_USB2_MODULE)
@@ -43,4 +65,15 @@ static inline int omap_usb2_set_comparator(struct phy_companion *comparator)
 }
 #endif
 
+static inline u32 omap_usb_readl(const void __iomem *addr, unsigned offset)
+{
+	return __raw_readl(addr + offset);
+}
+
+static inline void omap_usb_writel(const void __iomem *addr, unsigned offset,
+								u32 data)
+{
+	__raw_writel(data, addr + offset);
+}
+
 #endif /* __DRIVERS_OMAP_USB_H */
-- 
1.7.9.5



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