diff options
Diffstat (limited to 'drivers/usb/musb/davinci.c')
| -rw-r--r-- | drivers/usb/musb/davinci.c | 462 |
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 0000000..75baf18 --- /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; +} |
