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Diffstat (limited to 'drivers/usb/musb/davinci.c')
-rw-r--r--drivers/usb/musb/davinci.c462
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;
+}
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