mfd: omap: control: usb-phy: introduce the ctrl-module usb driver

Created a new platform driver for the platform device created by the
control module mfd core, wrt usb. This driver has API's to power on/off
the phy and the API's to write to musb mailbox.

(p.s. the mailbox for musb in omap4 is present in system control
module)

Change-Id: I3260e7e9b2091b75620b85ede5b2a09d097a9b37
[kishon@ti.com: wrote the original API's related to USB functions]
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Radhesh Fadnis <radhesh.fadnis@ti.com>

5 files changed, 197 insertions, 0 deletions

diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
index 1720ccc76ef9..b91614cc9db7 100644
--- a/drivers/usb/otg/Kconfig
+++ b/drivers/usb/otg/Kconfig
@@ -86,6 +86,19 @@ config TWL6030_USB
 	  are hooked to this driver through platform_data structure.
 	  The definition of internal PHY APIs are in the mach-omap2 layer.
 
+config OMAP4_USB_PHY
+	tristate "Texas Instruments OMAP4+ USB pin control driver"
+	depends on MFD_OMAP_CONTROL
+	help
+	  If you say yes here you get support for the Texas Instruments
+	  OMAP4+ USB pin control driver. The register set is part of system
+	  control module.
+
+	  USB phy in OMAP configures control module register for powering on
+	  the phy, configuring VBUSVALID, AVALID, IDDIG and SESSEND. For
+	  performing the above mentioned configuration, API's are added in
+	  by this children of the control module driver.
+
 config NOP_USB_XCEIV
 	tristate "NOP USB Transceiver Driver"
 	select USB_OTG_UTILS
diff --git a/drivers/usb/otg/Makefile b/drivers/usb/otg/Makefile
index b64b18e719a4..049238468082 100644
--- a/drivers/usb/otg/Makefile
+++ b/drivers/usb/otg/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_USB_GPIO_VBUS)	+= gpio_vbus.o
 obj-$(CONFIG_ISP1301_OMAP)	+= isp1301_omap.o
 obj-$(CONFIG_TWL4030_USB)	+= twl4030-usb.o
 obj-$(CONFIG_TWL6030_USB)	+= twl6030-usb.o
+obj-$(CONFIG_OMAP4_USB_PHY)	+= omap4-usb-phy.o
 obj-$(CONFIG_NOP_USB_XCEIV)	+= nop-usb-xceiv.o
 obj-$(CONFIG_USB_ULPI)		+= ulpi.o
 obj-$(CONFIG_USB_ULPI_VIEWPORT)	+= ulpi_viewport.o
diff --git a/drivers/usb/otg/omap4-usb-phy.c b/drivers/usb/otg/omap4-usb-phy.c
new file mode 100644
index 000000000000..4fb29fc9be47
--- /dev/null
+++ b/drivers/usb/otg/omap4-usb-phy.c
@@ -0,0 +1,129 @@
+/*
+ * OMAP4 system control module driver, USB control children
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Contact:
+ *    Kishon Vijay Abraham I <kishon@ti.com>
+ *    Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/omap_control.h>
+#include <linux/usb/omap4_usb_phy.h>
+
+/**
+ * omap4_usb_phy_power - power on/off the phy using control module reg
+ * @dev: struct device *
+ * @on: 0 or 1, based on powering on or off the PHY
+ *
+ * omap_usb2 can call this API to power on or off the PHY.
+ */
+int omap4_usb_phy_power(struct device *dev, int on)
+{
+	u32 val;
+	int ret;
+
+	if (on) {
+		ret = omap_control_readl(dev, CONTROL_DEV_CONF, &val);
+		if (!ret && (val & PHY_PD)) {
+			ret = omap_control_writel(dev, ~PHY_PD,
+						  CONTROL_DEV_CONF);
+			mdelay(200);
+		}
+	} else {
+		ret = omap_control_writel(dev, PHY_PD, CONTROL_DEV_CONF);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(omap4_usb_phy_power);
+
+/**
+ * omap4_usb_phy_mailbox - write to usb otg mailbox
+ * @dev: struct device *
+ * @val: the value to be written to the mailbox
+ *
+ * On detection of a device (ID pin is grounded), the phy should call this API
+ * to set AVALID, VBUSVALID and ID pin is grounded.
+ *
+ * When OMAP is connected to a host (OMAP in device mode), the phy should call
+ * this API to set AVALID, VBUSVALID and ID pin in high impedance.
+ *
+ * The phy should call this API, if OMAP is disconnected from host or device.
+ */
+int omap4_usb_phy_mailbox(struct device *dev, u32 val)
+{
+	return omap_control_writel(dev, val, CONTROL_USBOTGHS_CONTROL);
+}
+EXPORT_SYMBOL_GPL(omap4_usb_phy_mailbox);
+
+static int __devinit omap_usb_phy_probe(struct platform_device *pdev)
+{
+	struct omap_control *omap_control;
+
+	omap_control = dev_get_drvdata(pdev->dev.parent);
+	/* just for the sake */
+	if (!omap_control) {
+		dev_err(&pdev->dev, "no omap_control in our parent\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __devexit omap_usb_phy_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id of_omap_usb_phy_match[] = {
+	{ .compatible = "ti,omap4-usb-phy", },
+	{ },
+};
+
+static struct platform_driver omap_usb_phy_driver = {
+	.probe = omap_usb_phy_probe,
+	.remove = __devexit_p(omap_usb_phy_remove),
+	.driver = {
+			.name	= "omap4-usb-phy",
+			.owner	= THIS_MODULE,
+			.of_match_table	= of_omap_usb_phy_match,
+	},
+};
+
+static int __init omap_usb_phy_init(void)
+{
+	return platform_driver_register(&omap_usb_phy_driver);
+}
+postcore_initcall(omap_usb_phy_init);
+
+static void __exit omap_usb_phy_exit(void)
+{
+	platform_driver_unregister(&omap_usb_phy_driver);
+}
+module_exit(omap_usb_phy_exit);
+
+MODULE_DESCRIPTION("OMAP4+ USB-phy driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform: omap4-usb-phy");
+MODULE_AUTHOR("Texas Instrument Inc.");
diff --git a/include/linux/mfd/omap_control.h b/include/linux/mfd/omap_control.h
index b9198828fee0..0ad5dd36c0e6 100644
--- a/include/linux/mfd/omap_control.h
+++ b/include/linux/mfd/omap_control.h
@@ -22,6 +22,9 @@
 #ifndef __DRIVERS_OMAP_CONTROL_H
 #define __DRIVERS_OMAP_CONTROL_H
 
+#define	CONTROL_DEV_CONF		0x00000300
+#define	CONTROL_USBOTGHS_CONTROL	0x0000033C
+
 /**
  * struct system control module - scm device structure
  * @dev: device pointer
diff --git a/include/linux/usb/omap4_usb_phy.h b/include/linux/usb/omap4_usb_phy.h
new file mode 100644
index 000000000000..218ce93b39ea
--- /dev/null
+++ b/include/linux/usb/omap4_usb_phy.h
@@ -0,0 +1,51 @@
+/*
+ * OMAP4 USB-phy
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Contact:
+ *    Kishon Vijay Abraham I <kishon@ti.com>
+ *    Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#ifndef __OMAP4_USB_PHY_H
+#define __OMAP4_USB_PHY_H
+
+#define	PHY_PD				0x1
+#define	AVALID				BIT(0)
+#define	BVALID				BIT(1)
+#define	VBUSVALID			BIT(2)
+#define	SESSEND				BIT(3)
+#define	IDDIG				BIT(4)
+
+/* USB-PHY helpers */
+#if (defined(CONFIG_OMAP4_USB_PHY)) || (defined(CONFIG_OMAP4_USB_PHY_MODULE))
+extern int omap4_usb_phy_mailbox(struct device *dev, u32 val);
+extern int omap4_usb_phy_power(struct device *dev, int on);
+#else
+static int omap4_usb_phy_mailbox(struct device *dev, u32 val)
+{
+	return 0;
+}
+static int omap4_usb_phy_power(struct device *dev, int on)
+{
+	return 0;
+}
+#endif
+
+#endif