usb: musb: Add support for ti81xx platform

TI81XX platform has two musb interfaces and uses CPPI4.1 DMA engine.
It has builtin USB PHYs as AM35x. The current set of patches adds support
for one instance and only in PIO mode.

[ balbi@ti.com : make it compile and solve a "may be used
	uninitialized" warning ]

Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: Ravi Babu <ravibabu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

4 files changed, 722 insertions, 2 deletions

diff --git a/drivers/usb/musb/Kconfig b/drivers/usb/musb/Kconfig
index f70cab3beeec..126c220aa09a 100644
--- a/drivers/usb/musb/Kconfig
+++ b/drivers/usb/musb/Kconfig
@@ -8,6 +8,7 @@ config USB_MUSB_HDRC
 	tristate 'Inventra Highspeed Dual Role Controller (TI, ADI, ...)'
 	depends on USB && USB_GADGET
 	select NOP_USB_XCEIV if (ARCH_DAVINCI || MACH_OMAP3EVM || BLACKFIN)
+	select NOP_USB_XCEIV if SOC_OMAPTI81XX
 	select TWL4030_USB if MACH_OMAP_3430SDP
 	select TWL6030_USB if MACH_OMAP_4430SDP || MACH_OMAP4_PANDA
 	select USB_OTG_UTILS
@@ -54,6 +55,10 @@ config USB_MUSB_AM35X
 	tristate "AM35x"
 	depends on ARCH_OMAP
 
+config USB_MUSB_DSPS
+	tristate "TI DSPS platforms"
+	depends on SOC_OMAPTI81XX
+
 config USB_MUSB_BLACKFIN
 	tristate "Blackfin"
 	depends on (BF54x && !BF544) || (BF52x && ! BF522 && !BF523)
@@ -70,7 +75,8 @@ choice
 	default USB_INVENTRA_DMA if USB_MUSB_OMAP2PLUS || USB_MUSB_BLACKFIN
 	default USB_TI_CPPI_DMA if USB_MUSB_DAVINCI
 	default USB_TUSB_OMAP_DMA if USB_MUSB_TUSB6010
-	default MUSB_PIO_ONLY if USB_MUSB_TUSB6010 || USB_MUSB_DA8XX || USB_MUSB_AM35X
+	default MUSB_PIO_ONLY if USB_MUSB_TUSB6010 || USB_MUSB_DA8XX || USB_MUSB_AM35X \
+				|| USB_MUSB_DSPS
 	help
 	  Unfortunately, only one option can be enabled here. Ideally one
 	  should be able to build all these drivers into one kernel to
diff --git a/drivers/usb/musb/Makefile b/drivers/usb/musb/Makefile
index 88bfb9dee4bf..3b858715b5ea 100644
--- a/drivers/usb/musb/Makefile
+++ b/drivers/usb/musb/Makefile
@@ -13,6 +13,7 @@ musb_hdrc-$(CONFIG_DEBUG_FS)			+= musb_debugfs.o
 # Hardware Glue Layer
 obj-$(CONFIG_USB_MUSB_OMAP2PLUS)		+= omap2430.o
 obj-$(CONFIG_USB_MUSB_AM35X)			+= am35x.o
+obj-$(CONFIG_USB_MUSB_DSPS)			+= musb_dsps.o
 obj-$(CONFIG_USB_MUSB_TUSB6010)			+= tusb6010.o
 obj-$(CONFIG_USB_MUSB_DAVINCI)			+= davinci.o
 obj-$(CONFIG_USB_MUSB_DA8XX)			+= da8xx.o
diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 66aaccf04490..db3dff854b71 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -1034,7 +1034,9 @@ static void musb_shutdown(struct platform_device *pdev)
 	|| defined(CONFIG_USB_MUSB_OMAP2PLUS)		\
 	|| defined(CONFIG_USB_MUSB_OMAP2PLUS_MODULE)	\
 	|| defined(CONFIG_USB_MUSB_AM35X)		\
-	|| defined(CONFIG_USB_MUSB_AM35X_MODULE)
+	|| defined(CONFIG_USB_MUSB_AM35X_MODULE)	\
+	|| defined(CONFIG_USB_MUSB_DSPS)		\
+	|| defined(CONFIG_USB_MUSB_DSPS_MODULE)
 static ushort __devinitdata fifo_mode = 4;
 #elif defined(CONFIG_USB_MUSB_UX500)			\
 	|| defined(CONFIG_USB_MUSB_UX500_MODULE)
diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c
new file mode 100644
index 000000000000..23db42db761a
--- /dev/null
+++ b/drivers/usb/musb/musb_dsps.c
@@ -0,0 +1,711 @@
+/*
+ * Texas Instruments DSPS platforms "glue layer"
+ *
+ * Copyright (C) 2012, by Texas Instruments
+ *
+ * Based on the am35x "glue layer" code.
+ *
+ * This file is part of the Inventra Controller Driver for Linux.
+ *
+ * The Inventra Controller Driver for Linux 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.
+ *
+ * The Inventra Controller Driver for Linux 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 The Inventra Controller Driver for Linux ; if not,
+ * write to the Free Software Foundation, Inc., 59 Temple Place,
+ * Suite 330, Boston, MA  02111-1307  USA
+ *
+ * musb_dsps.c will be a common file for all the TI DSPS platforms
+ * such as dm64x, dm36x, dm35x, da8x, am35x and ti81x.
+ * For now only ti81x is using this and in future davinci.c, am35x.c
+ * da8xx.c would be merged to this file after testing.
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/pm_runtime.h>
+#include <linux/module.h>
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+
+#include <plat/usb.h>
+
+#include "musb_core.h"
+
+/**
+ * avoid using musb_readx()/musb_writex() as glue layer should not be
+ * dependent on musb core layer symbols.
+ */
+static inline u8 dsps_readb(const void __iomem *addr, unsigned offset)
+	{ return __raw_readb(addr + offset); }
+
+static inline u32 dsps_readl(const void __iomem *addr, unsigned offset)
+	{ return __raw_readl(addr + offset); }
+
+static inline void dsps_writeb(void __iomem *addr, unsigned offset, u8 data)
+	{ __raw_writeb(data, addr + offset); }
+
+static inline void dsps_writel(void __iomem *addr, unsigned offset, u32 data)
+	{ __raw_writel(data, addr + offset); }
+
+/**
+ * DSPS musb wrapper register offset.
+ * FIXME: This should be expanded to have all the wrapper registers from TI DSPS
+ * musb ips.
+ */
+struct dsps_musb_wrapper {
+	u16	revision;
+	u16	control;
+	u16	status;
+	u16	eoi;
+	u16	epintr_set;
+	u16	epintr_clear;
+	u16	epintr_status;
+	u16	coreintr_set;
+	u16	coreintr_clear;
+	u16	coreintr_status;
+	u16	phy_utmi;
+	u16	mode;
+
+	/* bit positions for control */
+	unsigned	reset:5;
+
+	/* bit positions for interrupt */
+	unsigned	usb_shift:5;
+	u32		usb_mask;
+	u32		usb_bitmap;
+	unsigned	drvvbus:5;
+
+	unsigned	txep_shift:5;
+	u32		txep_mask;
+	u32		txep_bitmap;
+
+	unsigned	rxep_shift:5;
+	u32		rxep_mask;
+	u32		rxep_bitmap;
+
+	/* bit positions for phy_utmi */
+	unsigned	otg_disable:5;
+
+	/* bit positions for mode */
+	unsigned	iddig:5;
+	/* miscellaneous stuff */
+	u32		musb_core_offset;
+	u8		poll_seconds;
+};
+
+/**
+ * DSPS glue structure.
+ */
+struct dsps_glue {
+	struct device *dev;
+	struct platform_device *musb;	/* child musb pdev */
+	const struct dsps_musb_wrapper *wrp; /* wrapper register offsets */
+	struct timer_list timer;	/* otg_workaround timer */
+};
+
+/**
+ * dsps_musb_enable - enable interrupts
+ */
+static void dsps_musb_enable(struct musb *musb)
+{
+	struct device *dev = musb->controller;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+	const struct dsps_musb_wrapper *wrp = glue->wrp;
+	void __iomem *reg_base = musb->ctrl_base;
+	u32 epmask, coremask;
+
+	/* Workaround: setup IRQs through both register sets. */
+	epmask = ((musb->epmask & wrp->txep_mask) << wrp->txep_shift) |
+	       ((musb->epmask & wrp->rxep_mask) << wrp->rxep_shift);
+	coremask = (wrp->usb_bitmap & ~MUSB_INTR_SOF);
+
+	dsps_writel(reg_base, wrp->epintr_set, epmask);
+	dsps_writel(reg_base, wrp->coreintr_set, coremask);
+	/* Force the DRVVBUS IRQ so we can start polling for ID change. */
+	if (is_otg_enabled(musb))
+		dsps_writel(reg_base, wrp->coreintr_set,
+			    (1 << wrp->drvvbus) << wrp->usb_shift);
+}
+
+/**
+ * dsps_musb_disable - disable HDRC and flush interrupts
+ */
+static void dsps_musb_disable(struct musb *musb)
+{
+	struct device *dev = musb->controller;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+	const struct dsps_musb_wrapper *wrp = glue->wrp;
+	void __iomem *reg_base = musb->ctrl_base;
+
+	dsps_writel(reg_base, wrp->coreintr_clear, wrp->usb_bitmap);
+	dsps_writel(reg_base, wrp->epintr_clear,
+			 wrp->txep_bitmap | wrp->rxep_bitmap);
+	dsps_writeb(musb->mregs, MUSB_DEVCTL, 0);
+	dsps_writel(reg_base, wrp->eoi, 0);
+}
+
+static void otg_timer(unsigned long _musb)
+{
+	struct musb *musb = (void *)_musb;
+	void __iomem *mregs = musb->mregs;
+	struct device *dev = musb->controller;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+	const struct dsps_musb_wrapper *wrp = glue->wrp;
+	u8 devctl;
+	unsigned long flags;
+
+	/*
+	 * We poll because DSPS IP's won't expose several OTG-critical
+	 * status change events (from the transceiver) otherwise.
+	 */
+	devctl = dsps_readb(mregs, MUSB_DEVCTL);
+	dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl,
+				otg_state_string(musb->xceiv->state));
+
+	spin_lock_irqsave(&musb->lock, flags);
+	switch (musb->xceiv->state) {
+	case OTG_STATE_A_WAIT_BCON:
+		devctl &= ~MUSB_DEVCTL_SESSION;
+		dsps_writeb(musb->mregs, MUSB_DEVCTL, devctl);
+
+		devctl = dsps_readb(musb->mregs, MUSB_DEVCTL);
+		if (devctl & MUSB_DEVCTL_BDEVICE) {
+			musb->xceiv->state = OTG_STATE_B_IDLE;
+			MUSB_DEV_MODE(musb);
+		} else {
+			musb->xceiv->state = OTG_STATE_A_IDLE;
+			MUSB_HST_MODE(musb);
+		}
+		break;
+	case OTG_STATE_A_WAIT_VFALL:
+		musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
+		dsps_writel(musb->ctrl_base, wrp->coreintr_set,
+			    MUSB_INTR_VBUSERROR << wrp->usb_shift);
+		break;
+	case OTG_STATE_B_IDLE:
+		if (!is_peripheral_enabled(musb))
+			break;
+
+		devctl = dsps_readb(mregs, MUSB_DEVCTL);
+		if (devctl & MUSB_DEVCTL_BDEVICE)
+			mod_timer(&glue->timer,
+					jiffies + wrp->poll_seconds * HZ);
+		else
+			musb->xceiv->state = OTG_STATE_A_IDLE;
+		break;
+	default:
+		break;
+	}
+	spin_unlock_irqrestore(&musb->lock, flags);
+}
+
+static void dsps_musb_try_idle(struct musb *musb, unsigned long timeout)
+{
+	struct device *dev = musb->controller;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+	static unsigned long last_timer;
+
+	if (!is_otg_enabled(musb))
+		return;
+
+	if (timeout == 0)
+		timeout = jiffies + msecs_to_jiffies(3);
+
+	/* Never idle if active, or when VBUS timeout is not set as host */
+	if (musb->is_active || (musb->a_wait_bcon == 0 &&
+				musb->xceiv->state == OTG_STATE_A_WAIT_BCON)) {
+		dev_dbg(musb->controller, "%s active, deleting timer\n",
+				otg_state_string(musb->xceiv->state));
+		del_timer(&glue->timer);
+		last_timer = jiffies;
+		return;
+	}
+
+	if (time_after(last_timer, timeout) && timer_pending(&glue->timer)) {
+		dev_dbg(musb->controller,
+			"Longer idle timer already pending, ignoring...\n");
+		return;
+	}
+	last_timer = timeout;
+
+	dev_dbg(musb->controller, "%s inactive, starting idle timer for %u ms\n",
+		otg_state_string(musb->xceiv->state),
+			jiffies_to_msecs(timeout - jiffies));
+	mod_timer(&glue->timer, timeout);
+}
+
+static irqreturn_t dsps_interrupt(int irq, void *hci)
+{
+	struct musb  *musb = hci;
+	void __iomem *reg_base = musb->ctrl_base;
+	struct device *dev = musb->controller;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+	const struct dsps_musb_wrapper *wrp = glue->wrp;
+	unsigned long flags;
+	irqreturn_t ret = IRQ_NONE;
+	u32 epintr, usbintr;
+
+	spin_lock_irqsave(&musb->lock, flags);
+
+	/* Get endpoint interrupts */
+	epintr = dsps_readl(reg_base, wrp->epintr_status);
+	musb->int_rx = (epintr & wrp->rxep_bitmap) >> wrp->rxep_shift;
+	musb->int_tx = (epintr & wrp->txep_bitmap) >> wrp->txep_shift;
+
+	if (epintr)
+		dsps_writel(reg_base, wrp->epintr_status, epintr);
+
+	/* Get usb core interrupts */
+	usbintr = dsps_readl(reg_base, wrp->coreintr_status);
+	if (!usbintr && !epintr)
+		goto eoi;
+
+	musb->int_usb =	(usbintr & wrp->usb_bitmap) >> wrp->usb_shift;
+	if (usbintr)
+		dsps_writel(reg_base, wrp->coreintr_status, usbintr);
+
+	dev_dbg(musb->controller, "usbintr (%x) epintr(%x)\n",
+			usbintr, epintr);
+	/*
+	 * DRVVBUS IRQs are the only proxy we have (a very poor one!) for
+	 * DSPS IP's missing ID change IRQ.  We need an ID change IRQ to
+	 * switch appropriately between halves of the OTG state machine.
+	 * Managing DEVCTL.SESSION per Mentor docs requires that we know its
+	 * value but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
+	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
+	 */
+	if ((usbintr & MUSB_INTR_BABBLE) && is_host_enabled(musb))
+		pr_info("CAUTION: musb: Babble Interrupt Occured\n");
+
+	if (usbintr & ((1 << wrp->drvvbus) << wrp->usb_shift)) {
+		int drvvbus = dsps_readl(reg_base, wrp->status);
+		void __iomem *mregs = musb->mregs;
+		u8 devctl = dsps_readb(mregs, MUSB_DEVCTL);
+		int err;
+
+		err = is_host_enabled(musb) && (musb->int_usb &
+						MUSB_INTR_VBUSERROR);
+		if (err) {
+			/*
+			 * The Mentor core doesn't debounce VBUS as needed
+			 * to cope with device connect current spikes. This
+			 * means it's not uncommon for bus-powered devices
+			 * to get VBUS errors during enumeration.
+			 *
+			 * This is a workaround, but newer RTL from Mentor
+			 * seems to allow a better one: "re"-starting sessions
+			 * without waiting for VBUS to stop registering in
+			 * devctl.
+			 */
+			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
+			musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
+			mod_timer(&glue->timer,
+					jiffies + wrp->poll_seconds * HZ);
+			WARNING("VBUS error workaround (delay coming)\n");
+		} else if (is_host_enabled(musb) && drvvbus) {
+			musb->is_active = 1;
+			MUSB_HST_MODE(musb);
+			musb->xceiv->otg->default_a = 1;
+			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
+			del_timer(&glue->timer);
+		} else {
+			musb->is_active = 0;
+			MUSB_DEV_MODE(musb);
+			musb->xceiv->otg->default_a = 0;
+			musb->xceiv->state = OTG_STATE_B_IDLE;
+		}
+
+		/* NOTE: this must complete power-on within 100 ms. */
+		dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n",
+				drvvbus ? "on" : "off",
+				otg_state_string(musb->xceiv->state),
+				err ? " ERROR" : "",
+				devctl);
+		ret = IRQ_HANDLED;
+	}
+
+	if (musb->int_tx || musb->int_rx || musb->int_usb)
+		ret |= musb_interrupt(musb);
+
+ eoi:
+	/* EOI needs to be written for the IRQ to be re-asserted. */
+	if (ret == IRQ_HANDLED || epintr || usbintr)
+		dsps_writel(reg_base, wrp->eoi, 1);
+
+	/* Poll for ID change */
+	if (is_otg_enabled(musb) && musb->xceiv->state == OTG_STATE_B_IDLE)
+		mod_timer(&glue->timer, jiffies + wrp->poll_seconds * HZ);
+
+	spin_unlock_irqrestore(&musb->lock, flags);
+
+	return ret;
+}
+
+static int dsps_musb_init(struct musb *musb)
+{
+	struct device *dev = musb->controller;
+	struct musb_hdrc_platform_data *plat = dev->platform_data;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+	const struct dsps_musb_wrapper *wrp = glue->wrp;
+	struct omap_musb_board_data *data = plat->board_data;
+	void __iomem *reg_base = musb->ctrl_base;
+	u32 rev, val;
+	int status;
+
+	/* mentor core register starts at offset of 0x400 from musb base */
+	musb->mregs += wrp->musb_core_offset;
+
+	/* NOP driver needs change if supporting dual instance */
+	usb_nop_xceiv_register();
+	musb->xceiv = usb_get_transceiver();
+	if (!musb->xceiv)
+		return -ENODEV;
+
+	/* Returns zero if e.g. not clocked */
+	rev = dsps_readl(reg_base, wrp->revision);
+	if (!rev) {
+		status = -ENODEV;
+		goto err0;
+	}
+
+	if (is_host_enabled(musb))
+		setup_timer(&glue->timer, otg_timer, (unsigned long) musb);
+
+	/* Reset the musb */
+	dsps_writel(reg_base, wrp->control, (1 << wrp->reset));
+
+	/* Start the on-chip PHY and its PLL. */
+	if (data->set_phy_power)
+		data->set_phy_power(1);
+
+	musb->isr = dsps_interrupt;
+
+	/* reset the otgdisable bit, needed for host mode to work */
+	val = dsps_readl(reg_base, wrp->phy_utmi);
+	val &= ~(1 << wrp->otg_disable);
+	dsps_writel(musb->ctrl_base, wrp->phy_utmi, val);
+
+	/* clear level interrupt */
+	dsps_writel(reg_base, wrp->eoi, 0);
+
+	return 0;
+err0:
+	usb_put_transceiver(musb->xceiv);
+	usb_nop_xceiv_unregister();
+	return status;
+}
+
+static int dsps_musb_exit(struct musb *musb)
+{
+	struct device *dev = musb->controller;
+	struct musb_hdrc_platform_data *plat = dev->platform_data;
+	struct omap_musb_board_data *data = plat->board_data;
+	struct platform_device *pdev = to_platform_device(dev->parent);
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+
+	if (is_host_enabled(musb))
+		del_timer_sync(&glue->timer);
+
+	/* Shutdown the on-chip PHY and its PLL. */
+	if (data->set_phy_power)
+		data->set_phy_power(0);
+
+	/* NOP driver needs change if supporting dual instance */
+	usb_put_transceiver(musb->xceiv);
+	usb_nop_xceiv_unregister();
+
+	return 0;
+}
+
+static struct musb_platform_ops dsps_ops = {
+	.init		= dsps_musb_init,
+	.exit		= dsps_musb_exit,
+
+	.enable		= dsps_musb_enable,
+	.disable	= dsps_musb_disable,
+
+	.try_idle	= dsps_musb_try_idle,
+};
+
+static u64 musb_dmamask = DMA_BIT_MASK(32);
+
+static int __devinit dsps_create_musb_pdev(struct dsps_glue *glue, u8 id)
+{
+	struct device *dev = glue->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct musb_hdrc_platform_data  *pdata = dev->platform_data;
+	struct platform_device	*musb;
+	struct resource *res;
+	struct resource	resources[2];
+	char res_name[10];
+	int ret;
+
+	/* get memory resource */
+	sprintf(res_name, "musb%d", id);
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, res_name);
+	if (!res) {
+		dev_err(dev, "%s get mem resource failed\n", res_name);
+		ret = -ENODEV;
+		goto err0;
+	}
+	res->parent = NULL;
+	resources[0] = *res;
+
+	/* get irq resource */
+	sprintf(res_name, "musb%d-irq", id);
+	res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, res_name);
+	if (!res) {
+		dev_err(dev, "%s get irq resource failed\n", res_name);
+		ret = -ENODEV;
+		goto err0;
+	}
+	strcpy((u8 *)res->name, "mc");
+	res->parent = NULL;
+	resources[1] = *res;
+
+	/* allocate the child platform device */
+	musb = platform_device_alloc("musb-hdrc", -1);
+	if (!musb) {
+		dev_err(dev, "failed to allocate musb device\n");
+		ret = -ENOMEM;
+		goto err0;
+	}
+
+	musb->dev.parent		= dev;
+	musb->dev.dma_mask		= &musb_dmamask;
+	musb->dev.coherent_dma_mask	= musb_dmamask;
+
+	glue->musb			= musb;
+
+	pdata->platform_ops		= &dsps_ops;
+
+	ret = platform_device_add_resources(musb, resources, 2);
+	if (ret) {
+		dev_err(dev, "failed to add resources\n");
+		goto err1;
+	}
+
+	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
+	if (ret) {
+		dev_err(dev, "failed to add platform_data\n");
+		goto err1;
+	}
+
+	ret = platform_device_add(musb);
+	if (ret) {
+		dev_err(dev, "failed to register musb device\n");
+		goto err1;
+	}
+
+	return 0;
+
+err1:
+	platform_device_put(musb);
+err0:
+	return ret;
+}
+
+static void __devexit dsps_delete_musb_pdev(struct dsps_glue *glue)
+{
+	platform_device_del(glue->musb);
+	platform_device_put(glue->musb);
+}
+
+static int __devinit dsps_probe(struct platform_device *pdev)
+{
+	const struct platform_device_id *id = platform_get_device_id(pdev);
+	const struct dsps_musb_wrapper *wrp =
+				(struct dsps_musb_wrapper *)id->driver_data;
+	struct dsps_glue *glue;
+	struct resource *iomem;
+	int ret;
+
+	/* allocate glue */
+	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
+	if (!glue) {
+		dev_err(&pdev->dev, "unable to allocate glue memory\n");
+		ret = -ENOMEM;
+		goto err0;
+	}
+
+	/* get memory resource */
+	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!iomem) {
+		dev_err(&pdev->dev, "failed to get usbss mem resourse\n");
+		ret = -ENODEV;
+		goto err1;
+	}
+
+	glue->dev = &pdev->dev;
+
+	glue->wrp = kmemdup(wrp, sizeof(*wrp), GFP_KERNEL);
+	if (!glue->wrp) {
+		dev_err(&pdev->dev, "failed to duplicate wrapper struct memory\n");
+		ret = -ENOMEM;
+		goto err1;
+	}
+	platform_set_drvdata(pdev, glue);
+
+	/* create the child platform device for first instances of musb */
+	ret = dsps_create_musb_pdev(glue, 0);
+	if (ret != 0) {
+		dev_err(&pdev->dev, "failed to create child pdev\n");
+		goto err2;
+	}
+
+	/* enable the usbss clocks */
+	pm_runtime_enable(&pdev->dev);
+
+	ret = pm_runtime_get_sync(&pdev->dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pm_runtime_get_sync FAILED");
+		goto err3;
+	}
+
+	return 0;
+
+err3:
+	pm_runtime_disable(&pdev->dev);
+err2:
+	kfree(glue->wrp);
+err1:
+	kfree(glue);
+err0:
+	return ret;
+}
+static int __devexit dsps_remove(struct platform_device *pdev)
+{
+	struct dsps_glue *glue = platform_get_drvdata(pdev);
+
+	/* delete the child platform device */
+	dsps_delete_musb_pdev(glue);
+
+	/* disable usbss clocks */
+	pm_runtime_put(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	kfree(glue->wrp);
+	kfree(glue);
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dsps_suspend(struct device *dev)
+{
+	struct musb_hdrc_platform_data *plat = dev->platform_data;
+	struct omap_musb_board_data *data = plat->board_data;
+
+	/* Shutdown the on-chip PHY and its PLL. */
+	if (data->set_phy_power)
+		data->set_phy_power(0);
+
+	return 0;
+}
+
+static int dsps_resume(struct device *dev)
+{
+	struct musb_hdrc_platform_data *plat = dev->platform_data;
+	struct omap_musb_board_data *data = plat->board_data;
+
+	/* Start the on-chip PHY and its PLL. */
+	if (data->set_phy_power)
+		data->set_phy_power(1);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(dsps_pm_ops, dsps_suspend, dsps_resume);
+
+static const struct dsps_musb_wrapper ti81xx_driver_data __devinitconst = {
+	.revision		= 0x00,
+	.control		= 0x14,
+	.status			= 0x18,
+	.eoi			= 0x24,
+	.epintr_set		= 0x38,
+	.epintr_clear		= 0x40,
+	.epintr_status		= 0x30,
+	.coreintr_set		= 0x3c,
+	.coreintr_clear		= 0x44,
+	.coreintr_status	= 0x34,
+	.phy_utmi		= 0xe0,
+	.mode			= 0xe8,
+	.reset			= 0,
+	.otg_disable		= 21,
+	.iddig			= 8,
+	.usb_shift		= 0,
+	.usb_mask		= 0x1ff,
+	.usb_bitmap		= (0x1ff << 0),
+	.drvvbus		= 8,
+	.txep_shift		= 0,
+	.txep_mask		= 0xffff,
+	.txep_bitmap		= (0xffff << 0),
+	.rxep_shift		= 16,
+	.rxep_mask		= 0xfffe,
+	.rxep_bitmap		= (0xfffe << 16),
+	.musb_core_offset	= 0x400,
+	.poll_seconds		= 2,
+};
+
+static const struct platform_device_id musb_dsps_id_table[] __devinitconst = {
+	{
+		.name	= "musb-ti81xx",
+		.driver_data	= (kernel_ulong_t) &ti81xx_driver_data,
+	},
+	{  },	/* Terminating Entry */
+};
+MODULE_DEVICE_TABLE(platform, musb_dsps_id_table);
+
+static const struct of_device_id musb_dsps_of_match[] __devinitconst = {
+	{ .compatible = "musb-ti81xx", },
+	{ .compatible = "ti,ti81xx-musb", },
+	{ .compatible = "ti,am335x-musb", },
+	{  },
+};
+MODULE_DEVICE_TABLE(of, musb_dsps_of_match);
+
+static struct platform_driver dsps_usbss_driver = {
+	.probe		= dsps_probe,
+	.remove         = __devexit_p(dsps_remove),
+	.driver         = {
+		.name   = "musb-dsps",
+		.pm	= &dsps_pm_ops,
+		.of_match_table	= musb_dsps_of_match,
+	},
+	.id_table	= musb_dsps_id_table,
+};
+
+MODULE_DESCRIPTION("TI DSPS MUSB Glue Layer");
+MODULE_AUTHOR("Ravi B <ravibabu@ti.com>");
+MODULE_AUTHOR("Ajay Kumar Gupta <ajay.gupta@ti.com>");
+MODULE_LICENSE("GPL v2");
+
+static int __init dsps_init(void)
+{
+	return platform_driver_register(&dsps_usbss_driver);
+}
+subsys_initcall(dsps_init);
+
+static void __exit dsps_exit(void)
+{
+	platform_driver_unregister(&dsps_usbss_driver);
+}
+module_exit(dsps_exit);