diff options
Diffstat (limited to 'drivers/usb/musb/davinci.c')
| -rw-r--r-- | drivers/usb/musb/davinci.c | 635 |
1 files changed, 635 insertions, 0 deletions
diff --git a/drivers/usb/musb/davinci.c b/drivers/usb/musb/davinci.c new file mode 100644 index 00000000..9d63ba4d --- /dev/null +++ b/drivers/usb/musb/davinci.c @@ -0,0 +1,635 @@ +/* + * 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/init.h> +#include <linux/list.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/gpio.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> + +#include <mach/cputype.h> +#include <mach/hardware.h> + +#include <asm/mach-types.h> + +#include "musb_core.h" + +#ifdef CONFIG_MACH_DAVINCI_EVM +#define GPIO_nVBUS_DRV 160 +#endif + +#include "davinci.h" +#include "cppi_dma.h" + + +#define USB_PHY_CTRL IO_ADDRESS(USBPHY_CTL_PADDR) +#define DM355_DEEPSLEEP IO_ADDRESS(DM355_DEEPSLEEP_PADDR) + +struct davinci_glue { + struct device *dev; + struct platform_device *musb; + struct clk *clk; +}; + +/* 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) +{ + u32 phy_ctrl = __raw_readl(USB_PHY_CTRL); + + /* power everything up; start the on-chip PHY and its PLL */ + phy_ctrl &= ~(USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN); + phy_ctrl |= USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON; + __raw_writel(phy_ctrl, USB_PHY_CTRL); + + /* wait for PLL to lock before proceeding */ + while ((__raw_readl(USB_PHY_CTRL) & USBPHY_PHYCLKGD) == 0) + cpu_relax(); +} + +static inline void phy_off(void) +{ + u32 phy_ctrl = __raw_readl(USB_PHY_CTRL); + + /* powerdown the on-chip PHY, its PLL, and the OTG block */ + phy_ctrl &= ~(USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON); + phy_ctrl |= USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN; + __raw_writel(phy_ctrl, USB_PHY_CTRL); +} + +static int dma_off = 1; + +static void davinci_musb_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 + */ +static void davinci_musb_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"); +} + + +#define portstate(stmt) stmt + +/* + * VBUS SWITCHING IS BOARD-SPECIFIC ... at least for the DM6446 EVM, + * which doesn't wire DRVVBUS to the FET that switches it. Unclear + * if that's a problem with the DM6446 chip or just with that board. + * + * In either case, the DM355 EVM automates DRVVBUS the normal way, + * when J10 is out, and TI documents it as handling OTG. + */ + +#ifdef CONFIG_MACH_DAVINCI_EVM + +static int vbus_state = -1; + +/* 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) +{ + gpio_set_value_cansleep(GPIO_nVBUS_DRV, vbus_state); + vbus_state = !vbus_state; +} + +#endif /* EVM */ + +static void davinci_musb_source_power(struct musb *musb, int is_on, int immediate) +{ +#ifdef CONFIG_MACH_DAVINCI_EVM + if (is_on) + is_on = 1; + + if (vbus_state == is_on) + return; + vbus_state = !is_on; /* 0/1 vs "-1 == unknown/init" */ + + if (machine_is_davinci_evm()) { + static DECLARE_WORK(evm_vbus_work, evm_deferred_drvvbus); + + if (immediate) + gpio_set_value_cansleep(GPIO_nVBUS_DRV, vbus_state); + else + schedule_work(&evm_vbus_work); + } + if (immediate) + vbus_state = is_on; +#endif +} + +static void davinci_musb_set_vbus(struct musb *musb, int is_on) +{ + WARN_ON(is_on && is_peripheral_active(musb)); + davinci_musb_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); + 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_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_musb_interrupt(int irq, void *__hci) +{ + unsigned long flags; + irqreturn_t retval = IRQ_NONE; + struct musb *musb = __hci; + struct usb_otg *otg = musb->xceiv->otg; + void __iomem *tibase = musb->ctrl_base; + struct cppi *cppi; + 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 associated 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. + */ + cppi = container_of(musb->dma_controller, struct cppi, controller); + if (is_cppi_enabled() && musb->dma_controller && !cppi->irq) + retval = cppi_interrupt(irq, __hci); + + /* 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); + dev_dbg(musb->controller, "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_HST_MODE(musb); + otg->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); + otg->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 + * (OTG_TIME_A_WAIT_VRISE) but we don't check for that. + */ + davinci_musb_source_power(musb, drvvbus, 0); + dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n", + drvvbus ? "on" : "off", + otg_state_string(musb->xceiv->state), + 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); + + return retval; +} + +static int davinci_musb_set_mode(struct musb *musb, u8 mode) +{ + /* EVM can't do this (right?) */ + return -EIO; +} + +static int davinci_musb_init(struct musb *musb) +{ + void __iomem *tibase = musb->ctrl_base; + u32 revision; + + usb_nop_xceiv_register(); + musb->xceiv = usb_get_transceiver(); + if (!musb->xceiv) + goto unregister; + + musb->mregs += DAVINCI_BASE_OFFSET; + + /* returns zero if e.g. not clocked */ + revision = musb_readl(tibase, DAVINCI_USB_VERSION_REG); + if (revision == 0) + goto fail; + + if (is_host_enabled(musb)) + setup_timer(&otg_workaround, otg_timer, (unsigned long) musb); + + davinci_musb_source_power(musb, 0, 1); + + /* dm355 EVM swaps D+/D- for signal integrity, and + * is clocked from the main 24 MHz crystal. + */ + if (machine_is_davinci_dm355_evm()) { + u32 phy_ctrl = __raw_readl(USB_PHY_CTRL); + + phy_ctrl &= ~(3 << 9); + phy_ctrl |= USBPHY_DATAPOL; + __raw_writel(phy_ctrl, USB_PHY_CTRL); + } + + /* On dm355, the default-A state machine needs DRVVBUS control. + * If we won't be a host, there's no need to turn it on. + */ + if (cpu_is_davinci_dm355()) { + u32 deepsleep = __raw_readl(DM355_DEEPSLEEP); + + if (is_host_enabled(musb)) { + deepsleep &= ~DRVVBUS_OVERRIDE; + } else { + deepsleep &= ~DRVVBUS_FORCE; + deepsleep |= DRVVBUS_OVERRIDE; + } + __raw_writel(deepsleep, DM355_DEEPSLEEP); + } + + /* 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(USB_PHY_CTRL), + musb_readb(tibase, DAVINCI_USB_CTRL_REG)); + + musb->isr = davinci_musb_interrupt; + return 0; + +fail: + usb_put_transceiver(musb->xceiv); +unregister: + usb_nop_xceiv_unregister(); + return -ENODEV; +} + +static int davinci_musb_exit(struct musb *musb) +{ + if (is_host_enabled(musb)) + del_timer_sync(&otg_workaround); + + /* force VBUS off */ + if (cpu_is_davinci_dm355()) { + u32 deepsleep = __raw_readl(DM355_DEEPSLEEP); + + deepsleep &= ~DRVVBUS_FORCE; + deepsleep |= DRVVBUS_OVERRIDE; + __raw_writel(deepsleep, DM355_DEEPSLEEP); + } + + davinci_musb_source_power(musb, 0 /*off*/, 1); + + /* delay, to avoid problems with module reload */ + if (is_host_enabled(musb) && musb->xceiv->otg->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; + dev_dbg(musb->controller, "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) + dev_dbg(musb->controller, "VBUS off timeout (devctl %02x)\n", devctl); + } + + phy_off(); + + usb_put_transceiver(musb->xceiv); + usb_nop_xceiv_unregister(); + + return 0; +} + +static const struct musb_platform_ops davinci_ops = { + .init = davinci_musb_init, + .exit = davinci_musb_exit, + + .enable = davinci_musb_enable, + .disable = davinci_musb_disable, + + .set_mode = davinci_musb_set_mode, + + .set_vbus = davinci_musb_set_vbus, +}; + +static u64 davinci_dmamask = DMA_BIT_MASK(32); + +static int __devinit davinci_probe(struct platform_device *pdev) +{ + struct musb_hdrc_platform_data *pdata = pdev->dev.platform_data; + struct platform_device *musb; + struct davinci_glue *glue; + struct clk *clk; + + int ret = -ENOMEM; + + glue = kzalloc(sizeof(*glue), GFP_KERNEL); + if (!glue) { + dev_err(&pdev->dev, "failed to allocate glue context\n"); + goto err0; + } + + musb = platform_device_alloc("musb-hdrc", -1); + if (!musb) { + dev_err(&pdev->dev, "failed to allocate musb device\n"); + goto err1; + } + + clk = clk_get(&pdev->dev, "usb"); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "failed to get clock\n"); + ret = PTR_ERR(clk); + goto err2; + } + + ret = clk_enable(clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable clock\n"); + goto err3; + } + + musb->dev.parent = &pdev->dev; + musb->dev.dma_mask = &davinci_dmamask; + musb->dev.coherent_dma_mask = davinci_dmamask; + + glue->dev = &pdev->dev; + glue->musb = musb; + glue->clk = clk; + + pdata->platform_ops = &davinci_ops; + + platform_set_drvdata(pdev, glue); + + ret = platform_device_add_resources(musb, pdev->resource, + pdev->num_resources); + if (ret) { + dev_err(&pdev->dev, "failed to add resources\n"); + goto err4; + } + + ret = platform_device_add_data(musb, pdata, sizeof(*pdata)); + if (ret) { + dev_err(&pdev->dev, "failed to add platform_data\n"); + goto err4; + } + + ret = platform_device_add(musb); + if (ret) { + dev_err(&pdev->dev, "failed to register musb device\n"); + goto err4; + } + + return 0; + +err4: + clk_disable(clk); + +err3: + clk_put(clk); + +err2: + platform_device_put(musb); + +err1: + kfree(glue); + +err0: + return ret; +} + +static int __devexit davinci_remove(struct platform_device *pdev) +{ + struct davinci_glue *glue = platform_get_drvdata(pdev); + + platform_device_del(glue->musb); + platform_device_put(glue->musb); + clk_disable(glue->clk); + clk_put(glue->clk); + kfree(glue); + + return 0; +} + +static struct platform_driver davinci_driver = { + .probe = davinci_probe, + .remove = __devexit_p(davinci_remove), + .driver = { + .name = "musb-davinci", + }, +}; + +MODULE_DESCRIPTION("DaVinci MUSB Glue Layer"); +MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>"); +MODULE_LICENSE("GPL v2"); + +static int __init davinci_init(void) +{ + return platform_driver_register(&davinci_driver); +} +module_init(davinci_init); + +static void __exit davinci_exit(void) +{ + platform_driver_unregister(&davinci_driver); +} +module_exit(davinci_exit); |