linux/arch/arm/mach-pxa/pxa3xx-ulpi.c
Marek Vasut a754aea25e ARM: pxa: fix pxa3xx-u2d crash when ULPI not used
In case the pxa3xx-u2d driver isn't used, probing of ohci-pxa27x will cause an
ugly kernel crash (NULL pointer dereference in pxa3xx_u2d_start_hc(), because
struct u2d is NULL and clk_enable() call will crash the kernel, trying to access
it).

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
2010-10-08 16:21:18 +08:00

401 lines
8.4 KiB
C

/*
* linux/arch/arm/mach-pxa/pxa3xx-ulpi.c
*
* code specific to pxa3xx aka Monahans
*
* Copyright (C) 2010 CompuLab Ltd.
*
* 2010-13-07: Igor Grinberg <grinberg@compulab.co.il>
* initial version: pxa310 USB Host mode support
*
* This program 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.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/usb.h>
#include <linux/usb/otg.h>
#include <mach/hardware.h>
#include <mach/regs-u2d.h>
#include <mach/pxa3xx-u2d.h>
struct pxa3xx_u2d_ulpi {
struct clk *clk;
void __iomem *mmio_base;
struct otg_transceiver *otg;
unsigned int ulpi_mode;
};
static struct pxa3xx_u2d_ulpi *u2d;
static inline u32 u2d_readl(u32 reg)
{
return __raw_readl(u2d->mmio_base + reg);
}
static inline void u2d_writel(u32 reg, u32 val)
{
__raw_writel(val, u2d->mmio_base + reg);
}
#if defined(CONFIG_PXA310_ULPI)
enum u2d_ulpi_phy_mode {
SYNCH = 0,
CARKIT = (1 << 0),
SER_3PIN = (1 << 1),
SER_6PIN = (1 << 2),
LOWPOWER = (1 << 3),
};
static inline enum u2d_ulpi_phy_mode pxa310_ulpi_get_phymode(void)
{
return (u2d_readl(U2DOTGUSR) >> 28) & 0xF;
}
static int pxa310_ulpi_poll(void)
{
int timeout = 50000;
while (timeout--) {
if (!(u2d_readl(U2DOTGUCR) & U2DOTGUCR_RUN))
return 0;
cpu_relax();
}
pr_warning("%s: ULPI access timed out!\n", __func__);
return -ETIMEDOUT;
}
static int pxa310_ulpi_read(struct otg_transceiver *otg, u32 reg)
{
int err;
if (pxa310_ulpi_get_phymode() != SYNCH) {
pr_warning("%s: PHY is not in SYNCH mode!\n", __func__);
return -EBUSY;
}
u2d_writel(U2DOTGUCR, U2DOTGUCR_RUN | U2DOTGUCR_RNW | (reg << 16));
msleep(5);
err = pxa310_ulpi_poll();
if (err)
return err;
return u2d_readl(U2DOTGUCR) & U2DOTGUCR_RDATA;
}
static int pxa310_ulpi_write(struct otg_transceiver *otg, u32 val, u32 reg)
{
if (pxa310_ulpi_get_phymode() != SYNCH) {
pr_warning("%s: PHY is not in SYNCH mode!\n", __func__);
return -EBUSY;
}
u2d_writel(U2DOTGUCR, U2DOTGUCR_RUN | (reg << 16) | (val << 8));
msleep(5);
return pxa310_ulpi_poll();
}
struct otg_io_access_ops pxa310_ulpi_access_ops = {
.read = pxa310_ulpi_read,
.write = pxa310_ulpi_write,
};
static void pxa310_otg_transceiver_rtsm(void)
{
u32 u2dotgcr;
/* put PHY to sync mode */
u2dotgcr = u2d_readl(U2DOTGCR);
u2dotgcr |= U2DOTGCR_RTSM | U2DOTGCR_UTMID;
u2d_writel(U2DOTGCR, u2dotgcr);
msleep(10);
/* setup OTG sync mode */
u2dotgcr = u2d_readl(U2DOTGCR);
u2dotgcr |= U2DOTGCR_ULAF;
u2dotgcr &= ~(U2DOTGCR_SMAF | U2DOTGCR_CKAF);
u2d_writel(U2DOTGCR, u2dotgcr);
}
static int pxa310_start_otg_host_transcvr(struct usb_bus *host)
{
int err;
pxa310_otg_transceiver_rtsm();
err = otg_init(u2d->otg);
if (err) {
pr_err("OTG transceiver init failed");
return err;
}
err = otg_set_vbus(u2d->otg, 1);
if (err) {
pr_err("OTG transceiver VBUS set failed");
return err;
}
err = otg_set_host(u2d->otg, host);
if (err)
pr_err("OTG transceiver Host mode set failed");
return err;
}
static int pxa310_start_otg_hc(struct usb_bus *host)
{
u32 u2dotgcr;
int err;
/* disable USB device controller */
u2d_writel(U2DCR, u2d_readl(U2DCR) & ~U2DCR_UDE);
u2d_writel(U2DOTGCR, u2d_readl(U2DOTGCR) | U2DOTGCR_UTMID);
u2d_writel(U2DOTGICR, u2d_readl(U2DOTGICR) & ~0x37F7F);
err = pxa310_start_otg_host_transcvr(host);
if (err)
return err;
/* set xceiver mode */
if (u2d->ulpi_mode & ULPI_IC_6PIN_SERIAL)
u2d_writel(U2DP3CR, u2d_readl(U2DP3CR) & ~U2DP3CR_P2SS);
else if (u2d->ulpi_mode & ULPI_IC_3PIN_SERIAL)
u2d_writel(U2DP3CR, u2d_readl(U2DP3CR) | U2DP3CR_P2SS);
/* start OTG host controller */
u2dotgcr = u2d_readl(U2DOTGCR) | U2DOTGCR_SMAF;
u2d_writel(U2DOTGCR, u2dotgcr & ~(U2DOTGCR_ULAF | U2DOTGCR_CKAF));
return 0;
}
static void pxa310_stop_otg_hc(void)
{
pxa310_otg_transceiver_rtsm();
otg_set_host(u2d->otg, NULL);
otg_set_vbus(u2d->otg, 0);
otg_shutdown(u2d->otg);
}
static void pxa310_u2d_setup_otg_hc(void)
{
u32 u2dotgcr;
u2dotgcr = u2d_readl(U2DOTGCR);
u2dotgcr |= U2DOTGCR_ULAF | U2DOTGCR_UTMID;
u2dotgcr &= ~(U2DOTGCR_SMAF | U2DOTGCR_CKAF);
u2d_writel(U2DOTGCR, u2dotgcr);
msleep(5);
u2d_writel(U2DOTGCR, u2dotgcr | U2DOTGCR_ULE);
msleep(5);
u2d_writel(U2DOTGICR, u2d_readl(U2DOTGICR) & ~0x37F7F);
}
static int pxa310_otg_init(struct pxa3xx_u2d_platform_data *pdata)
{
unsigned int ulpi_mode = ULPI_OTG_DRVVBUS;
if (pdata) {
if (pdata->ulpi_mode & ULPI_SER_6PIN)
ulpi_mode |= ULPI_IC_6PIN_SERIAL;
else if (pdata->ulpi_mode & ULPI_SER_3PIN)
ulpi_mode |= ULPI_IC_3PIN_SERIAL;
}
u2d->ulpi_mode = ulpi_mode;
u2d->otg = otg_ulpi_create(&pxa310_ulpi_access_ops, ulpi_mode);
if (!u2d->otg)
return -ENOMEM;
u2d->otg->io_priv = u2d->mmio_base;
return 0;
}
static void pxa310_otg_exit(void)
{
kfree(u2d->otg);
}
#else
static inline void pxa310_u2d_setup_otg_hc(void) {}
static inline int pxa310_start_otg_hc(struct usb_bus *host)
{
return 0;
}
static inline void pxa310_stop_otg_hc(void) {}
static inline int pxa310_otg_init(struct pxa3xx_u2d_platform_data *pdata)
{
return 0;
}
static inline void pxa310_otg_exit(void) {}
#endif /* CONFIG_PXA310_ULPI */
int pxa3xx_u2d_start_hc(struct usb_bus *host)
{
int err = 0;
/* In case the PXA3xx ULPI isn't used, do nothing. */
if (!u2d)
return 0;
clk_enable(u2d->clk);
if (cpu_is_pxa310()) {
pxa310_u2d_setup_otg_hc();
err = pxa310_start_otg_hc(host);
}
return err;
}
void pxa3xx_u2d_stop_hc(struct usb_bus *host)
{
/* In case the PXA3xx ULPI isn't used, do nothing. */
if (!u2d)
return;
if (cpu_is_pxa310())
pxa310_stop_otg_hc();
clk_disable(u2d->clk);
}
static int pxa3xx_u2d_probe(struct platform_device *pdev)
{
struct pxa3xx_u2d_platform_data *pdata = pdev->dev.platform_data;
struct resource *r;
int err;
u2d = kzalloc(sizeof(struct pxa3xx_u2d_ulpi), GFP_KERNEL);
if (!u2d) {
dev_err(&pdev->dev, "failed to allocate memory\n");
return -ENOMEM;
}
u2d->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(u2d->clk)) {
dev_err(&pdev->dev, "failed to get u2d clock\n");
err = PTR_ERR(u2d->clk);
goto err_free_mem;
}
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!r) {
dev_err(&pdev->dev, "no IO memory resource defined\n");
err = -ENODEV;
goto err_put_clk;
}
r = request_mem_region(r->start, resource_size(r), pdev->name);
if (!r) {
dev_err(&pdev->dev, "failed to request memory resource\n");
err = -EBUSY;
goto err_put_clk;
}
u2d->mmio_base = ioremap(r->start, resource_size(r));
if (!u2d->mmio_base) {
dev_err(&pdev->dev, "ioremap() failed\n");
err = -ENODEV;
goto err_free_res;
}
if (pdata->init) {
err = pdata->init(&pdev->dev);
if (err)
goto err_free_io;
}
/* Only PXA310 U2D has OTG functionality */
if (cpu_is_pxa310()) {
err = pxa310_otg_init(pdata);
if (err)
goto err_free_plat;
}
platform_set_drvdata(pdev, &u2d);
return 0;
err_free_plat:
if (pdata->exit)
pdata->exit(&pdev->dev);
err_free_io:
iounmap(u2d->mmio_base);
err_free_res:
release_mem_region(r->start, resource_size(r));
err_put_clk:
clk_put(u2d->clk);
err_free_mem:
kfree(u2d);
return err;
}
static int pxa3xx_u2d_remove(struct platform_device *pdev)
{
struct pxa3xx_u2d_platform_data *pdata = pdev->dev.platform_data;
struct resource *r;
if (cpu_is_pxa310()) {
pxa310_stop_otg_hc();
pxa310_otg_exit();
}
if (pdata->exit)
pdata->exit(&pdev->dev);
platform_set_drvdata(pdev, NULL);
iounmap(u2d->mmio_base);
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(r->start, resource_size(r));
clk_put(u2d->clk);
kfree(u2d);
return 0;
}
static struct platform_driver pxa3xx_u2d_ulpi_driver = {
.driver = {
.name = "pxa3xx-u2d",
.owner = THIS_MODULE,
},
.probe = pxa3xx_u2d_probe,
.remove = pxa3xx_u2d_remove,
};
static int pxa3xx_u2d_ulpi_init(void)
{
return platform_driver_register(&pxa3xx_u2d_ulpi_driver);
}
module_init(pxa3xx_u2d_ulpi_init);
static void __exit pxa3xx_u2d_ulpi_exit(void)
{
platform_driver_unregister(&pxa3xx_u2d_ulpi_driver);
}
module_exit(pxa3xx_u2d_ulpi_exit);
MODULE_DESCRIPTION("PXA3xx U2D ULPI driver");
MODULE_AUTHOR("Igor Grinberg");
MODULE_LICENSE("GPL v2");