diff options
Diffstat (limited to 'kernel/drivers/usb/musb/am35x.c')
| -rw-r--r-- | kernel/drivers/usb/musb/am35x.c | 626 |
1 files changed, 626 insertions, 0 deletions
diff --git a/kernel/drivers/usb/musb/am35x.c b/kernel/drivers/usb/musb/am35x.c new file mode 100644 index 000000000..220fd4d3b --- /dev/null +++ b/kernel/drivers/usb/musb/am35x.c @@ -0,0 +1,626 @@ + +/* + * 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/module.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/usb/usb_phy_generic.h> +#include <linux/platform_data/usb-omap.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 + +struct am35x_glue { + struct device *dev; + struct platform_device *musb; + struct platform_device *phy; + struct clk *phy_clk; + struct clk *clk; +}; + +/* + * am35x_musb_enable - enable interrupts + */ +static void am35x_musb_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. */ + musb_writel(reg_base, CORE_INTR_SRC_SET_REG, + AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT); +} + +/* + * am35x_musb_disable - disable HDRC and flush interrupts + */ +static void am35x_musb_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); +} + +#define portstate(stmt) stmt + +static void am35x_musb_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); + dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl, + usb_otg_state_string(musb->xceiv->otg->state)); + + spin_lock_irqsave(&musb->lock, flags); + switch (musb->xceiv->otg->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->otg->state = OTG_STATE_B_IDLE; + MUSB_DEV_MODE(musb); + } else { + musb->xceiv->otg->state = OTG_STATE_A_IDLE; + MUSB_HST_MODE(musb); + } + break; + case OTG_STATE_A_WAIT_VFALL: + musb->xceiv->otg->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: + devctl = musb_readb(mregs, MUSB_DEVCTL); + if (devctl & MUSB_DEVCTL_BDEVICE) + mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ); + else + musb->xceiv->otg->state = OTG_STATE_A_IDLE; + break; + default: + break; + } + spin_unlock_irqrestore(&musb->lock, flags); +} + +static void am35x_musb_try_idle(struct musb *musb, unsigned long timeout) +{ + static unsigned long last_timer; + + 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->otg->state == OTG_STATE_A_WAIT_BCON)) { + dev_dbg(musb->controller, "%s active, deleting timer\n", + usb_otg_state_string(musb->xceiv->otg->state)); + del_timer(&otg_workaround); + last_timer = jiffies; + return; + } + + if (time_after(last_timer, timeout) && timer_pending(&otg_workaround)) { + dev_dbg(musb->controller, "Longer idle timer already pending, ignoring...\n"); + return; + } + last_timer = timeout; + + dev_dbg(musb->controller, "%s inactive, starting idle timer for %u ms\n", + usb_otg_state_string(musb->xceiv->otg->state), + jiffies_to_msecs(timeout - jiffies)); + mod_timer(&otg_workaround, timeout); +} + +static irqreturn_t am35x_musb_interrupt(int irq, void *hci) +{ + struct musb *musb = hci; + void __iomem *reg_base = musb->ctrl_base; + struct device *dev = musb->controller; + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); + struct omap_musb_board_data *data = plat->board_data; + struct usb_otg *otg = musb->xceiv->otg; + unsigned long flags; + irqreturn_t ret = IRQ_NONE; + u32 epintr, usbintr; + + 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 = 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->otg->state = OTG_STATE_A_WAIT_VFALL; + mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ); + WARNING("VBUS error workaround (delay coming)\n"); + } else if (drvvbus) { + MUSB_HST_MODE(musb); + otg->default_a = 1; + musb->xceiv->otg->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->otg->state = OTG_STATE_B_IDLE; + portstate(musb->port1_status &= ~USB_PORT_STAT_POWER); + } + + /* NOTE: this must complete power-on within 100 ms. */ + dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n", + drvvbus ? "on" : "off", + usb_otg_state_string(musb->xceiv->otg->state), + err ? " ERROR" : "", + devctl); + ret = IRQ_HANDLED; + } + + /* Drop spurious RX and TX if device is disconnected */ + if (musb->int_usb & MUSB_INTR_DISCONNECT) { + musb->int_tx = 0; + musb->int_rx = 0; + } + + 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 */ + if (data->clear_irq) + data->clear_irq(); + /* write EOI */ + musb_writel(reg_base, USB_END_OF_INTR_REG, 0); + } + + /* Poll for ID change */ + if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) + mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ); + + spin_unlock_irqrestore(&musb->lock, flags); + + return ret; +} + +static int am35x_musb_set_mode(struct musb *musb, u8 musb_mode) +{ + struct device *dev = musb->controller; + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); + struct omap_musb_board_data *data = plat->board_data; + int retval = 0; + + if (data->set_mode) + data->set_mode(musb_mode); + else + retval = -EIO; + + return retval; +} + +static int am35x_musb_init(struct musb *musb) +{ + struct device *dev = musb->controller; + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); + struct omap_musb_board_data *data = plat->board_data; + void __iomem *reg_base = musb->ctrl_base; + u32 rev; + + musb->mregs += USB_MENTOR_CORE_OFFSET; + + /* Returns zero if e.g. not clocked */ + rev = musb_readl(reg_base, USB_REVISION_REG); + if (!rev) + return -ENODEV; + + musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2); + if (IS_ERR_OR_NULL(musb->xceiv)) + return -EPROBE_DEFER; + + setup_timer(&otg_workaround, otg_timer, (unsigned long) musb); + + /* Reset the musb */ + if (data->reset) + data->reset(); + + /* Reset the controller */ + musb_writel(reg_base, USB_CTRL_REG, AM35X_SOFT_RESET_MASK); + + /* Start the on-chip PHY and its PLL. */ + if (data->set_phy_power) + data->set_phy_power(1); + + msleep(5); + + musb->isr = am35x_musb_interrupt; + + /* clear level interrupt */ + if (data->clear_irq) + data->clear_irq(); + + return 0; +} + +static int am35x_musb_exit(struct musb *musb) +{ + struct device *dev = musb->controller; + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); + struct omap_musb_board_data *data = plat->board_data; + + del_timer_sync(&otg_workaround); + + /* Shutdown the on-chip PHY and its PLL. */ + if (data->set_phy_power) + data->set_phy_power(0); + + usb_put_phy(musb->xceiv); + + return 0; +} + +/* AM35x supports only 32bit read operation */ +static void am35x_read_fifo(struct musb_hw_ep *hw_ep, u16 len, u8 *dst) +{ + void __iomem *fifo = hw_ep->fifo; + u32 val; + int i; + + /* Read for 32bit-aligned destination address */ + if (likely((0x03 & (unsigned long) dst) == 0) && len >= 4) { + readsl(fifo, dst, len >> 2); + dst += len & ~0x03; + len &= 0x03; + } + /* + * Now read the remaining 1 to 3 byte or complete length if + * unaligned address. + */ + if (len > 4) { + for (i = 0; i < (len >> 2); i++) { + *(u32 *) dst = musb_readl(fifo, 0); + dst += 4; + } + len &= 0x03; + } + if (len > 0) { + val = musb_readl(fifo, 0); + memcpy(dst, &val, len); + } +} + +static const struct musb_platform_ops am35x_ops = { + .quirks = MUSB_INDEXED_EP, + .init = am35x_musb_init, + .exit = am35x_musb_exit, + + .read_fifo = am35x_read_fifo, + .enable = am35x_musb_enable, + .disable = am35x_musb_disable, + + .set_mode = am35x_musb_set_mode, + .try_idle = am35x_musb_try_idle, + + .set_vbus = am35x_musb_set_vbus, +}; + +static const struct platform_device_info am35x_dev_info = { + .name = "musb-hdrc", + .id = PLATFORM_DEVID_AUTO, + .dma_mask = DMA_BIT_MASK(32), +}; + +static int am35x_probe(struct platform_device *pdev) +{ + struct musb_hdrc_platform_data *pdata = dev_get_platdata(&pdev->dev); + struct platform_device *musb; + struct am35x_glue *glue; + struct platform_device_info pinfo; + struct clk *phy_clk; + 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; + } + + phy_clk = clk_get(&pdev->dev, "fck"); + if (IS_ERR(phy_clk)) { + dev_err(&pdev->dev, "failed to get PHY clock\n"); + ret = PTR_ERR(phy_clk); + goto err3; + } + + clk = clk_get(&pdev->dev, "ick"); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "failed to get clock\n"); + ret = PTR_ERR(clk); + goto err4; + } + + ret = clk_enable(phy_clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable PHY clock\n"); + goto err5; + } + + ret = clk_enable(clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable clock\n"); + goto err6; + } + + glue->dev = &pdev->dev; + glue->phy_clk = phy_clk; + glue->clk = clk; + + pdata->platform_ops = &am35x_ops; + + glue->phy = usb_phy_generic_register(); + if (IS_ERR(glue->phy)) + goto err7; + platform_set_drvdata(pdev, glue); + + pinfo = am35x_dev_info; + pinfo.parent = &pdev->dev; + pinfo.res = pdev->resource; + pinfo.num_res = pdev->num_resources; + pinfo.data = pdata; + pinfo.size_data = sizeof(*pdata); + + glue->musb = musb = platform_device_register_full(&pinfo); + if (IS_ERR(musb)) { + ret = PTR_ERR(musb); + dev_err(&pdev->dev, "failed to register musb device: %d\n", ret); + goto err8; + } + + return 0; + +err8: + usb_phy_generic_unregister(glue->phy); + +err7: + clk_disable(clk); + +err6: + clk_disable(phy_clk); + +err5: + clk_put(clk); + +err4: + clk_put(phy_clk); + +err3: + kfree(glue); + +err0: + return ret; +} + +static int am35x_remove(struct platform_device *pdev) +{ + struct am35x_glue *glue = platform_get_drvdata(pdev); + + platform_device_unregister(glue->musb); + usb_phy_generic_unregister(glue->phy); + clk_disable(glue->clk); + clk_disable(glue->phy_clk); + clk_put(glue->clk); + clk_put(glue->phy_clk); + kfree(glue); + + return 0; +} + +#ifdef CONFIG_PM +static int am35x_suspend(struct device *dev) +{ + struct am35x_glue *glue = dev_get_drvdata(dev); + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); + struct omap_musb_board_data *data = plat->board_data; + + /* Shutdown the on-chip PHY and its PLL. */ + if (data->set_phy_power) + data->set_phy_power(0); + + clk_disable(glue->phy_clk); + clk_disable(glue->clk); + + return 0; +} + +static int am35x_resume(struct device *dev) +{ + struct am35x_glue *glue = dev_get_drvdata(dev); + struct musb_hdrc_platform_data *plat = dev_get_platdata(dev); + struct omap_musb_board_data *data = plat->board_data; + int ret; + + /* Start the on-chip PHY and its PLL. */ + if (data->set_phy_power) + data->set_phy_power(1); + + ret = clk_enable(glue->phy_clk); + if (ret) { + dev_err(dev, "failed to enable PHY clock\n"); + return ret; + } + + ret = clk_enable(glue->clk); + if (ret) { + dev_err(dev, "failed to enable clock\n"); + return ret; + } + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(am35x_pm_ops, am35x_suspend, am35x_resume); + +static struct platform_driver am35x_driver = { + .probe = am35x_probe, + .remove = am35x_remove, + .driver = { + .name = "musb-am35x", + .pm = &am35x_pm_ops, + }, +}; + +MODULE_DESCRIPTION("AM35x MUSB Glue Layer"); +MODULE_AUTHOR("Ajay Kumar Gupta <ajay.gupta@ti.com>"); +MODULE_LICENSE("GPL v2"); +module_platform_driver(am35x_driver); |