/*
* 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/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/nop-usb-xceiv.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 clk *phy_clk;
struct clk *clk;
};
#define glue_to_musb(g) platform_get_drvdata(g->musb)
/*
* 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->state));
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:
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 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->state == OTG_STATE_A_WAIT_BCON)) {
dev_dbg(musb->controller, "%s active, deleting timer\n",
usb_otg_state_string(musb->xceiv->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->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->platform_data;
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->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->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 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->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->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->platform_data;
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->platform_data;
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;
usb_nop_xceiv_register();
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->platform_data;
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);
usb_nop_xceiv_unregister();
return 0;
}
/* AM35x supports only 32bit read operation */
void musb_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 = {
.init = am35x_musb_init,
.exit = am35x_musb_exit,
.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 u64 am35x_dmamask = DMA_BIT_MASK(32);
static int am35x_probe(struct platform_device *pdev)
{
struct musb_hdrc_platform_data *pdata = pdev->dev.platform_data;
struct platform_device *musb;
struct am35x_glue *glue;
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;
}
musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
if (!musb) {
dev_err(&pdev->dev, "failed to allocate musb device\n");
goto err1;
}
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;
}
musb->dev.parent = &pdev->dev;
musb->dev.dma_mask = &am35x_dmamask;
musb->dev.coherent_dma_mask = am35x_dmamask;
glue->dev = &pdev->dev;
glue->musb = musb;
glue->phy_clk = phy_clk;
glue->clk = clk;
pdata->platform_ops = &am35x_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 err7;
}
ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
if (ret) {
dev_err(&pdev->dev, "failed to add platform_data\n");
goto err7;
}
ret = platform_device_add(musb);
if (ret) {
dev_err(&pdev->dev, "failed to register musb device\n");
goto err7;
}
return 0;
err7:
clk_disable(clk);
err6:
clk_disable(phy_clk);
err5:
clk_put(clk);
err4:
clk_put(phy_clk);
err3:
platform_device_put(musb);
err1:
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);
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->platform_data;
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->platform_data;
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;
}
static struct dev_pm_ops am35x_pm_ops = {
.suspend = am35x_suspend,
.resume = am35x_resume,
};
#define DEV_PM_OPS &am35x_pm_ops
#else
#define DEV_PM_OPS NULL
#endif
static struct platform_driver am35x_driver = {
.probe = am35x_probe,
.remove = am35x_remove,
.driver = {
.name = "musb-am35x",
.pm = DEV_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);