diff options
Diffstat (limited to 'drivers/usb/musb/am35x.c')
| -rw-r--r-- | drivers/usb/musb/am35x.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/drivers/usb/musb/am35x.c b/drivers/usb/musb/am35x.c new file mode 100644 index 00000000000..53962a0389e --- /dev/null +++ b/drivers/usb/musb/am35x.c @@ -0,0 +1,494 @@ +/* + * Texas Instruments AM35x "glue layer" + * + * Copyright (c) 2010, by Texas Instruments + * + * Based on the DA8xx "glue layer" code. + * Copyright (c) 2008-2009, MontaVista Software, Inc. <source@mvista.com> + * + * 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/init.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include <plat/control.h> +#include <plat/usb.h> + +#include "musb_core.h" + +/* + * AM35x specific definitions + */ +/* USB 2.0 OTG module registers */ +#define USB_REVISION_REG 0x00 +#define USB_CTRL_REG 0x04 +#define USB_STAT_REG 0x08 +#define USB_EMULATION_REG 0x0c +/* 0x10 Reserved */ +#define USB_AUTOREQ_REG 0x14 +#define USB_SRP_FIX_TIME_REG 0x18 +#define USB_TEARDOWN_REG 0x1c +#define EP_INTR_SRC_REG 0x20 +#define EP_INTR_SRC_SET_REG 0x24 +#define EP_INTR_SRC_CLEAR_REG 0x28 +#define EP_INTR_MASK_REG 0x2c +#define EP_INTR_MASK_SET_REG 0x30 +#define EP_INTR_MASK_CLEAR_REG 0x34 +#define EP_INTR_SRC_MASKED_REG 0x38 +#define CORE_INTR_SRC_REG 0x40 +#define CORE_INTR_SRC_SET_REG 0x44 +#define CORE_INTR_SRC_CLEAR_REG 0x48 +#define CORE_INTR_MASK_REG 0x4c +#define CORE_INTR_MASK_SET_REG 0x50 +#define CORE_INTR_MASK_CLEAR_REG 0x54 +#define CORE_INTR_SRC_MASKED_REG 0x58 +/* 0x5c Reserved */ +#define USB_END_OF_INTR_REG 0x60 + +/* Control register bits */ +#define AM35X_SOFT_RESET_MASK 1 + +/* USB interrupt register bits */ +#define AM35X_INTR_USB_SHIFT 16 +#define AM35X_INTR_USB_MASK (0x1ff << AM35X_INTR_USB_SHIFT) +#define AM35X_INTR_DRVVBUS 0x100 +#define AM35X_INTR_RX_SHIFT 16 +#define AM35X_INTR_TX_SHIFT 0 +#define AM35X_TX_EP_MASK 0xffff /* EP0 + 15 Tx EPs */ +#define AM35X_RX_EP_MASK 0xfffe /* 15 Rx EPs */ +#define AM35X_TX_INTR_MASK (AM35X_TX_EP_MASK << AM35X_INTR_TX_SHIFT) +#define AM35X_RX_INTR_MASK (AM35X_RX_EP_MASK << AM35X_INTR_RX_SHIFT) + +#define USB_MENTOR_CORE_OFFSET 0x400 + +static inline void phy_on(void) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(100); + u32 devconf2; + + /* + * Start the on-chip PHY and its PLL. + */ + devconf2 = omap_ctrl_readl(AM35XX_CONTROL_DEVCONF2); + + devconf2 &= ~(CONF2_RESET | CONF2_PHYPWRDN | CONF2_OTGPWRDN); + devconf2 |= CONF2_PHY_PLLON; + + omap_ctrl_writel(devconf2, AM35XX_CONTROL_DEVCONF2); + + DBG(1, "Waiting for PHY clock good...\n"); + while (!(omap_ctrl_readl(AM35XX_CONTROL_DEVCONF2) + & CONF2_PHYCLKGD)) { + cpu_relax(); + + if (time_after(jiffies, timeout)) { + DBG(1, "musb PHY clock good timed out\n"); + break; + } + } +} + +static inline void phy_off(void) +{ + u32 devconf2; + + /* + * Power down the on-chip PHY. + */ + devconf2 = omap_ctrl_readl(AM35XX_CONTROL_DEVCONF2); + + devconf2 &= ~CONF2_PHY_PLLON; + devconf2 |= CONF2_PHYPWRDN | CONF2_OTGPWRDN; + omap_ctrl_writel(devconf2, AM35XX_CONTROL_DEVCONF2); +} + +/* + * musb_platform_enable - enable interrupts + */ +void musb_platform_enable(struct musb *musb) +{ + void __iomem *reg_base = musb->ctrl_base; + u32 epmask; + + /* Workaround: setup IRQs through both register sets. */ + epmask = ((musb->epmask & AM35X_TX_EP_MASK) << AM35X_INTR_TX_SHIFT) | + ((musb->epmask & AM35X_RX_EP_MASK) << AM35X_INTR_RX_SHIFT); + + musb_writel(reg_base, EP_INTR_MASK_SET_REG, epmask); + musb_writel(reg_base, CORE_INTR_MASK_SET_REG, AM35X_INTR_USB_MASK); + + /* Force the DRVVBUS IRQ so we can start polling for ID change. */ + if (is_otg_enabled(musb)) + musb_writel(reg_base, CORE_INTR_SRC_SET_REG, + AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT); +} + +/* + * musb_platform_disable - disable HDRC and flush interrupts + */ +void musb_platform_disable(struct musb *musb) +{ + void __iomem *reg_base = musb->ctrl_base; + + musb_writel(reg_base, CORE_INTR_MASK_CLEAR_REG, AM35X_INTR_USB_MASK); + musb_writel(reg_base, EP_INTR_MASK_CLEAR_REG, + AM35X_TX_INTR_MASK | AM35X_RX_INTR_MASK); + musb_writeb(musb->mregs, MUSB_DEVCTL, 0); + musb_writel(reg_base, USB_END_OF_INTR_REG, 0); +} + +#ifdef CONFIG_USB_MUSB_HDRC_HCD +#define portstate(stmt) stmt +#else +#define portstate(stmt) +#endif + +static void am35x_set_vbus(struct musb *musb, int is_on) +{ + WARN_ON(is_on && is_peripheral_active(musb)); +} + +#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 AM35x'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_BCON: + devctl &= ~MUSB_DEVCTL_SESSION; + musb_writeb(musb->mregs, MUSB_DEVCTL, devctl); + + devctl = musb_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; + musb_writel(musb->ctrl_base, CORE_INTR_SRC_SET_REG, + MUSB_INTR_VBUSERROR << AM35X_INTR_USB_SHIFT); + break; + case OTG_STATE_B_IDLE: + if (!is_peripheral_enabled(musb)) + break; + + 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); +} + +void musb_platform_try_idle(struct musb *musb, unsigned long timeout) +{ + 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)) { + DBG(4, "%s active, deleting timer\n", otg_state_string(musb)); + del_timer(&otg_workaround); + last_timer = jiffies; + return; + } + + if (time_after(last_timer, timeout) && timer_pending(&otg_workaround)) { + DBG(4, "Longer idle timer already pending, ignoring...\n"); + return; + } + last_timer = timeout; + + DBG(4, "%s inactive, starting idle timer for %u ms\n", + otg_state_string(musb), jiffies_to_msecs(timeout - jiffies)); + mod_timer(&otg_workaround, timeout); +} + +static irqreturn_t am35x_interrupt(int irq, void *hci) +{ + struct musb *musb = hci; + void __iomem *reg_base = musb->ctrl_base; + unsigned long flags; + irqreturn_t ret = IRQ_NONE; + u32 epintr, usbintr, lvl_intr; + + spin_lock_irqsave(&musb->lock, flags); + + /* Get endpoint interrupts */ + epintr = musb_readl(reg_base, EP_INTR_SRC_MASKED_REG); + + if (epintr) { + musb_writel(reg_base, EP_INTR_SRC_CLEAR_REG, epintr); + + musb->int_rx = + (epintr & AM35X_RX_INTR_MASK) >> AM35X_INTR_RX_SHIFT; + musb->int_tx = + (epintr & AM35X_TX_INTR_MASK) >> AM35X_INTR_TX_SHIFT; + } + + /* Get usb core interrupts */ + usbintr = musb_readl(reg_base, CORE_INTR_SRC_MASKED_REG); + if (!usbintr && !epintr) + goto eoi; + + if (usbintr) { + musb_writel(reg_base, CORE_INTR_SRC_CLEAR_REG, usbintr); + + musb->int_usb = + (usbintr & AM35X_INTR_USB_MASK) >> AM35X_INTR_USB_SHIFT; + } + /* + * DRVVBUS IRQs are the only proxy we have (a very poor one!) for + * AM35x'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 & (AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT)) { + int drvvbus = musb_readl(reg_base, USB_STAT_REG); + void __iomem *mregs = musb->mregs; + u8 devctl = musb_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(&otg_workaround, jiffies + POLL_SECONDS * HZ); + WARNING("VBUS error workaround (delay coming)\n"); + } else if (is_host_enabled(musb) && drvvbus) { + 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 power-on within 100 ms. */ + DBG(2, "VBUS %s (%s)%s, devctl %02x\n", + drvvbus ? "on" : "off", + otg_state_string(musb), + 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) { + /* clear level interrupt */ + lvl_intr = omap_ctrl_readl(AM35XX_CONTROL_LVL_INTR_CLEAR); + lvl_intr |= AM35XX_USBOTGSS_INT_CLR; + omap_ctrl_writel(lvl_intr, AM35XX_CONTROL_LVL_INTR_CLEAR); + /* write EOI */ + musb_writel(reg_base, USB_END_OF_INTR_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 ret; +} + +int musb_platform_set_mode(struct musb *musb, u8 musb_mode) +{ + u32 devconf2 = omap_ctrl_readl(AM35XX_CONTROL_DEVCONF2); + + devconf2 &= ~CONF2_OTGMODE; + switch (musb_mode) { +#ifdef CONFIG_USB_MUSB_HDRC_HCD + case MUSB_HOST: /* Force VBUS valid, ID = 0 */ + devconf2 |= CONF2_FORCE_HOST; + break; +#endif +#ifdef CONFIG_USB_GADGET_MUSB_HDRC + case MUSB_PERIPHERAL: /* Force VBUS valid, ID = 1 */ + devconf2 |= CONF2_FORCE_DEVICE; + break; +#endif +#ifdef CONFIG_USB_MUSB_OTG + case MUSB_OTG: /* Don't override the VBUS/ID comparators */ + devconf2 |= CONF2_NO_OVERRIDE; + break; +#endif + default: + DBG(2, "Trying to set unsupported mode %u\n", musb_mode); + } + + omap_ctrl_writel(devconf2, AM35XX_CONTROL_DEVCONF2); + return 0; +} + +int __init musb_platform_init(struct musb *musb, void *board_data) +{ + void __iomem *reg_base = musb->ctrl_base; + u32 rev, lvl_intr, sw_reset; + int status; + + musb->mregs += USB_MENTOR_CORE_OFFSET; + + clk_enable(musb->clock); + DBG(2, "musb->clock=%lud\n", clk_get_rate(musb->clock)); + + musb->phy_clock = clk_get(musb->controller, "fck"); + if (IS_ERR(musb->phy_clock)) { + status = PTR_ERR(musb->phy_clock); + goto exit0; + } + clk_enable(musb->phy_clock); + DBG(2, "musb->phy_clock=%lud\n", clk_get_rate(musb->phy_clock)); + + /* Returns zero if e.g. not clocked */ + rev = musb_readl(reg_base, USB_REVISION_REG); + if (!rev) { + status = -ENODEV; + goto exit1; + } + + usb_nop_xceiv_register(); + musb->xceiv = otg_get_transceiver(); + if (!musb->xceiv) { + status = -ENODEV; + goto exit1; + } + + if (is_host_enabled(musb)) + setup_timer(&otg_workaround, otg_timer, (unsigned long) musb); + + musb->board_set_vbus = am35x_set_vbus; + + /* Global reset */ + sw_reset = omap_ctrl_readl(AM35XX_CONTROL_IP_SW_RESET); + + sw_reset |= AM35XX_USBOTGSS_SW_RST; + omap_ctrl_writel(sw_reset, AM35XX_CONTROL_IP_SW_RESET); + + sw_reset &= ~AM35XX_USBOTGSS_SW_RST; + omap_ctrl_writel(sw_reset, AM35XX_CONTROL_IP_SW_RESET); + + /* Reset the controller */ + musb_writel(reg_base, USB_CTRL_REG, AM35X_SOFT_RESET_MASK); + + /* Start the on-chip PHY and its PLL. */ + phy_on(); + + msleep(5); + + musb->isr = am35x_interrupt; + + /* clear level interrupt */ + lvl_intr = omap_ctrl_readl(AM35XX_CONTROL_LVL_INTR_CLEAR); + lvl_intr |= AM35XX_USBOTGSS_INT_CLR; + omap_ctrl_writel(lvl_intr, AM35XX_CONTROL_LVL_INTR_CLEAR); + return 0; +exit1: + clk_disable(musb->phy_clock); + clk_put(musb->phy_clock); +exit0: + clk_disable(musb->clock); + return status; +} + +int musb_platform_exit(struct musb *musb) +{ + if (is_host_enabled(musb)) + del_timer_sync(&otg_workaround); + + phy_off(); + + otg_put_transceiver(musb->xceiv); + usb_nop_xceiv_unregister(); + + clk_disable(musb->clock); + + clk_disable(musb->phy_clock); + clk_put(musb->phy_clock); + + return 0; +} + +#ifdef CONFIG_PM +void musb_platform_save_context(struct musb *musb, + struct musb_context_registers *musb_context) +{ + phy_off(); +} + +void musb_platform_restore_context(struct musb *musb, + struct musb_context_registers *musb_context) +{ + phy_on(); +} +#endif |