USB: Add MUSB and TUSB support

This patch adds support for MUSB and TUSB controllers
integrated into omap2430 and davinci. It also adds support
for external tusb6010 controller.

Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 462 insertions, 0 deletions

diff --git a/drivers/usb/musb/davinci.c b/drivers/usb/musb/davinci.c
new file mode 100644
index 000000000000..75baf181a8cd
--- /dev/null
+++ b/drivers/usb/musb/davinci.c
@@ -0,0 +1,462 @@
+/*
+ * Copyright (C) 2005-2006 by Texas Instruments
+ *
+ * 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
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <asm/arch/hardware.h>
+#include <asm/arch/memory.h>
+#include <asm/arch/gpio.h>
+#include <asm/mach-types.h>
+
+#include "musb_core.h"
+
+#ifdef CONFIG_MACH_DAVINCI_EVM
+#include <asm/arch/i2c-client.h>
+#endif
+
+#include "davinci.h"
+#include "cppi_dma.h"
+
+
+/* REVISIT (PM) we should be able to keep the PHY in low power mode most
+ * of the time (24 MHZ oscillator and PLL off, etc) by setting POWER.D0
+ * and, when in host mode, autosuspending idle root ports... PHYPLLON
+ * (overriding SUSPENDM?) then likely needs to stay off.
+ */
+
+static inline void phy_on(void)
+{
+	/* start the on-chip PHY and its PLL */
+	__raw_writel(USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON,
+			(void __force __iomem *) IO_ADDRESS(USBPHY_CTL_PADDR));
+	while ((__raw_readl((void __force __iomem *)
+				IO_ADDRESS(USBPHY_CTL_PADDR))
+			& USBPHY_PHYCLKGD) == 0)
+		cpu_relax();
+}
+
+static inline void phy_off(void)
+{
+	/* powerdown the on-chip PHY and its oscillator */
+	__raw_writel(USBPHY_OSCPDWN | USBPHY_PHYPDWN, (void __force __iomem *)
+			IO_ADDRESS(USBPHY_CTL_PADDR));
+}
+
+static int dma_off = 1;
+
+void musb_platform_enable(struct musb *musb)
+{
+	u32	tmp, old, val;
+
+	/* workaround:  setup irqs through both register sets */
+	tmp = (musb->epmask & DAVINCI_USB_TX_ENDPTS_MASK)
+			<< DAVINCI_USB_TXINT_SHIFT;
+	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
+	old = tmp;
+	tmp = (musb->epmask & (0xfffe & DAVINCI_USB_RX_ENDPTS_MASK))
+			<< DAVINCI_USB_RXINT_SHIFT;
+	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
+	tmp |= old;
+
+	val = ~MUSB_INTR_SOF;
+	tmp |= ((val & 0x01ff) << DAVINCI_USB_USBINT_SHIFT);
+	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
+
+	if (is_dma_capable() && !dma_off)
+		printk(KERN_WARNING "%s %s: dma not reactivated\n",
+				__FILE__, __func__);
+	else
+		dma_off = 0;
+
+	/* force a DRVVBUS irq so we can start polling for ID change */
+	if (is_otg_enabled(musb))
+		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
+			DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT);
+}
+
+/*
+ * Disable the HDRC and flush interrupts
+ */
+void musb_platform_disable(struct musb *musb)
+{
+	/* because we don't set CTRLR.UINT, "important" to:
+	 *  - not read/write INTRUSB/INTRUSBE
+	 *  - (except during initial setup, as workaround)
+	 *  - use INTSETR/INTCLRR instead
+	 */
+	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_CLR_REG,
+			  DAVINCI_USB_USBINT_MASK
+			| DAVINCI_USB_TXINT_MASK
+			| DAVINCI_USB_RXINT_MASK);
+	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
+	musb_writel(musb->ctrl_base, DAVINCI_USB_EOI_REG, 0);
+
+	if (is_dma_capable() && !dma_off)
+		WARNING("dma still active\n");
+}
+
+
+/* REVISIT it's not clear whether DaVinci can support full OTG.  */
+
+static int vbus_state = -1;
+
+#ifdef CONFIG_USB_MUSB_HDRC_HCD
+#define	portstate(stmt)		stmt
+#else
+#define	portstate(stmt)
+#endif
+
+
+/* VBUS SWITCHING IS BOARD-SPECIFIC */
+
+#ifdef CONFIG_MACH_DAVINCI_EVM
+#ifndef CONFIG_MACH_DAVINCI_EVM_OTG
+
+/* I2C operations are always synchronous, and require a task context.
+ * With unloaded systems, using the shared workqueue seems to suffice
+ * to satisfy the 100msec A_WAIT_VRISE timeout...
+ */
+static void evm_deferred_drvvbus(struct work_struct *ignored)
+{
+	davinci_i2c_expander_op(0x3a, USB_DRVVBUS, vbus_state);
+	vbus_state = !vbus_state;
+}
+static DECLARE_WORK(evm_vbus_work, evm_deferred_drvvbus);
+
+#endif	/* modified board */
+#endif	/* EVM */
+
+static void davinci_source_power(struct musb *musb, int is_on, int immediate)
+{
+	if (is_on)
+		is_on = 1;
+
+	if (vbus_state == is_on)
+		return;
+	vbus_state = !is_on;		/* 0/1 vs "-1 == unknown/init" */
+
+#ifdef CONFIG_MACH_DAVINCI_EVM
+	if (machine_is_davinci_evm()) {
+#ifdef CONFIG_MACH_DAVINCI_EVM_OTG
+		/* modified EVM board switching VBUS with GPIO(6) not I2C
+		 * NOTE:  PINMUX0.RGB888 (bit23) must be clear
+		 */
+		if (is_on)
+			gpio_set(GPIO(6));
+		else
+			gpio_clear(GPIO(6));
+		immediate = 1;
+#else
+		if (immediate)
+			davinci_i2c_expander_op(0x3a, USB_DRVVBUS, !is_on);
+		else
+			schedule_work(&evm_vbus_work);
+#endif
+	}
+#endif
+	if (immediate)
+		vbus_state = is_on;
+}
+
+static void davinci_set_vbus(struct musb *musb, int is_on)
+{
+	WARN_ON(is_on && is_peripheral_active(musb));
+	davinci_source_power(musb, is_on, 0);
+}
+
+
+#define	POLL_SECONDS	2
+
+static struct timer_list otg_workaround;
+
+static void otg_timer(unsigned long _musb)
+{
+	struct musb		*musb = (void *)_musb;
+	void __iomem		*mregs = musb->mregs;
+	u8			devctl;
+	unsigned long		flags;
+
+	/* We poll because DaVinci's won't expose several OTG-critical
+	* status change events (from the transceiver) otherwise.
+	 */
+	devctl = musb_readb(mregs, MUSB_DEVCTL);
+	DBG(7, "poll devctl %02x (%s)\n", devctl, otg_state_string(musb));
+
+	spin_lock_irqsave(&musb->lock, flags);
+	switch (musb->xceiv.state) {
+	case OTG_STATE_A_WAIT_VFALL:
+		/* Wait till VBUS falls below SessionEnd (~0.2V); the 1.3 RTL
+		 * seems to mis-handle session "start" otherwise (or in our
+		 * case "recover"), in routine "VBUS was valid by the time
+		 * VBUSERR got reported during enumeration" cases.
+		 */
+		if (devctl & MUSB_DEVCTL_VBUS) {
+			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
+			break;
+		}
+		musb->xceiv.state = OTG_STATE_A_WAIT_VRISE;
+		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
+			MUSB_INTR_VBUSERROR << DAVINCI_USB_USBINT_SHIFT);
+		break;
+	case OTG_STATE_B_IDLE:
+		if (!is_peripheral_enabled(musb))
+			break;
+
+		/* There's no ID-changed IRQ, so we have no good way to tell
+		 * when to switch to the A-Default state machine (by setting
+		 * the DEVCTL.SESSION flag).
+		 *
+		 * Workaround:  whenever we're in B_IDLE, try setting the
+		 * session flag every few seconds.  If it works, ID was
+		 * grounded and we're now in the A-Default state machine.
+		 *
+		 * NOTE setting the session flag is _supposed_ to trigger
+		 * SRP, but clearly it doesn't.
+		 */
+		musb_writeb(mregs, MUSB_DEVCTL,
+				devctl | MUSB_DEVCTL_SESSION);
+		devctl = musb_readb(mregs, MUSB_DEVCTL);
+		if (devctl & MUSB_DEVCTL_BDEVICE)
+			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
+		else
+			musb->xceiv.state = OTG_STATE_A_IDLE;
+		break;
+	default:
+		break;
+	}
+	spin_unlock_irqrestore(&musb->lock, flags);
+}
+
+static irqreturn_t davinci_interrupt(int irq, void *__hci)
+{
+	unsigned long	flags;
+	irqreturn_t	retval = IRQ_NONE;
+	struct musb	*musb = __hci;
+	void __iomem	*tibase = musb->ctrl_base;
+	u32		tmp;
+
+	spin_lock_irqsave(&musb->lock, flags);
+
+	/* NOTE: DaVinci shadows the Mentor IRQs.  Don't manage them through
+	 * the Mentor registers (except for setup), use the TI ones and EOI.
+	 *
+	 * Docs describe irq "vector" registers asociated with the CPPI and
+	 * USB EOI registers.  These hold a bitmask corresponding to the
+	 * current IRQ, not an irq handler address.  Would using those bits
+	 * resolve some of the races observed in this dispatch code??
+	 */
+
+	/* CPPI interrupts share the same IRQ line, but have their own
+	 * mask, state, "vector", and EOI registers.
+	 */
+	if (is_cppi_enabled()) {
+		u32 cppi_tx = musb_readl(tibase, DAVINCI_TXCPPI_MASKED_REG);
+		u32 cppi_rx = musb_readl(tibase, DAVINCI_RXCPPI_MASKED_REG);
+
+		if (cppi_tx || cppi_rx) {
+			DBG(4, "CPPI IRQ t%x r%x\n", cppi_tx, cppi_rx);
+			cppi_completion(musb, cppi_rx, cppi_tx);
+			retval = IRQ_HANDLED;
+		}
+	}
+
+	/* ack and handle non-CPPI interrupts */
+	tmp = musb_readl(tibase, DAVINCI_USB_INT_SRC_MASKED_REG);
+	musb_writel(tibase, DAVINCI_USB_INT_SRC_CLR_REG, tmp);
+	DBG(4, "IRQ %08x\n", tmp);
+
+	musb->int_rx = (tmp & DAVINCI_USB_RXINT_MASK)
+			>> DAVINCI_USB_RXINT_SHIFT;
+	musb->int_tx = (tmp & DAVINCI_USB_TXINT_MASK)
+			>> DAVINCI_USB_TXINT_SHIFT;
+	musb->int_usb = (tmp & DAVINCI_USB_USBINT_MASK)
+			>> DAVINCI_USB_USBINT_SHIFT;
+
+	/* DRVVBUS irqs are the only proxy we have (a very poor one!) for
+	 * DaVinci'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 we know its
+	 * value, but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
+	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
+	 */
+	if (tmp & (DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT)) {
+		int	drvvbus = musb_readl(tibase, DAVINCI_USB_STAT_REG);
+		void __iomem *mregs = musb->mregs;
+		u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
+		int	err = musb->int_usb & MUSB_INTR_VBUSERROR;
+
+		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 (on EVM, a **long** time) for VBUS
+			 * to stop registering in devctl.
+			 */
+			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
+			musb->xceiv.state = OTG_STATE_A_WAIT_VFALL;
+			mod_timer(&otg_workaround, jiffies + 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.default_a = 1;
+			musb->xceiv.state = OTG_STATE_A_WAIT_VRISE;
+			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
+			del_timer(&otg_workaround);
+		} else {
+			musb->is_active = 0;
+			MUSB_DEV_MODE(musb);
+			musb->xceiv.default_a = 0;
+			musb->xceiv.state = OTG_STATE_B_IDLE;
+			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
+		}
+
+		/* NOTE:  this must complete poweron within 100 msec */
+		davinci_source_power(musb, drvvbus, 0);
+		DBG(2, "VBUS %s (%s)%s, devctl %02x\n",
+				drvvbus ? "on" : "off",
+				otg_state_string(musb),
+				err ? " ERROR" : "",
+				devctl);
+		retval = IRQ_HANDLED;
+	}
+
+	if (musb->int_tx || musb->int_rx || musb->int_usb)
+		retval |= musb_interrupt(musb);
+
+	/* irq stays asserted until EOI is written */
+	musb_writel(tibase, DAVINCI_USB_EOI_REG, 0);
+
+	/* poll for ID change */
+	if (is_otg_enabled(musb)
+			&& musb->xceiv.state == OTG_STATE_B_IDLE)
+		mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
+
+	spin_unlock_irqrestore(&musb->lock, flags);
+
+	/* REVISIT we sometimes get unhandled IRQs
+	 * (e.g. ep0).  not clear why...
+	 */
+	if (retval != IRQ_HANDLED)
+		DBG(5, "unhandled? %08x\n", tmp);
+	return IRQ_HANDLED;
+}
+
+int __init musb_platform_init(struct musb *musb)
+{
+	void __iomem	*tibase = musb->ctrl_base;
+	u32		revision;
+
+	musb->mregs += DAVINCI_BASE_OFFSET;
+#if 0
+	/* REVISIT there's something odd about clocking, this
+	 * didn't appear do the job ...
+	 */
+	musb->clock = clk_get(pDevice, "usb");
+	if (IS_ERR(musb->clock))
+		return PTR_ERR(musb->clock);
+
+	status = clk_enable(musb->clock);
+	if (status < 0)
+		return -ENODEV;
+#endif
+
+	/* returns zero if e.g. not clocked */
+	revision = musb_readl(tibase, DAVINCI_USB_VERSION_REG);
+	if (revision == 0)
+		return -ENODEV;
+
+	if (is_host_enabled(musb))
+		setup_timer(&otg_workaround, otg_timer, (unsigned long) musb);
+
+	musb->board_set_vbus = davinci_set_vbus;
+	davinci_source_power(musb, 0, 1);
+
+	/* reset the controller */
+	musb_writel(tibase, DAVINCI_USB_CTRL_REG, 0x1);
+
+	/* start the on-chip PHY and its PLL */
+	phy_on();
+
+	msleep(5);
+
+	/* NOTE:  irqs are in mixed mode, not bypass to pure-musb */
+	pr_debug("DaVinci OTG revision %08x phy %03x control %02x\n",
+		revision, __raw_readl((void __force __iomem *)
+				IO_ADDRESS(USBPHY_CTL_PADDR)),
+		musb_readb(tibase, DAVINCI_USB_CTRL_REG));
+
+	musb->isr = davinci_interrupt;
+	return 0;
+}
+
+int musb_platform_exit(struct musb *musb)
+{
+	if (is_host_enabled(musb))
+		del_timer_sync(&otg_workaround);
+
+	davinci_source_power(musb, 0 /*off*/, 1);
+
+	/* delay, to avoid problems with module reload */
+	if (is_host_enabled(musb) && musb->xceiv.default_a) {
+		int	maxdelay = 30;
+		u8	devctl, warn = 0;
+
+		/* if there's no peripheral connected, this can take a
+		 * long time to fall, especially on EVM with huge C133.
+		 */
+		do {
+			devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
+			if (!(devctl & MUSB_DEVCTL_VBUS))
+				break;
+			if ((devctl & MUSB_DEVCTL_VBUS) != warn) {
+				warn = devctl & MUSB_DEVCTL_VBUS;
+				DBG(1, "VBUS %d\n",
+					warn >> MUSB_DEVCTL_VBUS_SHIFT);
+			}
+			msleep(1000);
+			maxdelay--;
+		} while (maxdelay > 0);
+
+		/* in OTG mode, another host might be connected */
+		if (devctl & MUSB_DEVCTL_VBUS)
+			DBG(1, "VBUS off timeout (devctl %02x)\n", devctl);
+	}
+
+	phy_off();
+	return 0;
+}