linux/drivers/usb/musb/musb_virthub.c
Paul Cercueil a6d45ea063 usb: musb: Allow running without CONFIG_USB_PHY
Modify the core so that musb->xceiv is never deferenced without being
checked first.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20221026182657.146630-4-paul@crapouillou.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-09 12:39:13 +01:00

440 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* MUSB OTG driver virtual root hub support
*
* Copyright 2005 Mentor Graphics Corporation
* Copyright (C) 2005-2006 by Texas Instruments
* Copyright (C) 2006-2007 Nokia Corporation
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/timer.h>
#include <asm/unaligned.h>
#include "musb_core.h"
void musb_host_finish_resume(struct work_struct *work)
{
struct musb *musb;
unsigned long flags;
u8 power;
musb = container_of(work, struct musb, finish_resume_work.work);
spin_lock_irqsave(&musb->lock, flags);
power = musb_readb(musb->mregs, MUSB_POWER);
power &= ~MUSB_POWER_RESUME;
musb_dbg(musb, "root port resume stopped, power %02x", power);
musb_writeb(musb->mregs, MUSB_POWER, power);
/*
* ISSUE: DaVinci (RTL 1.300) disconnects after
* resume of high speed peripherals (but not full
* speed ones).
*/
musb->is_active = 1;
musb->port1_status &= ~(USB_PORT_STAT_SUSPEND | MUSB_PORT_STAT_RESUME);
musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
usb_hcd_poll_rh_status(musb->hcd);
/* NOTE: it might really be A_WAIT_BCON ... */
musb_set_state(musb, OTG_STATE_A_HOST);
spin_unlock_irqrestore(&musb->lock, flags);
}
int musb_port_suspend(struct musb *musb, bool do_suspend)
{
u8 power;
void __iomem *mbase = musb->mregs;
if (!is_host_active(musb))
return 0;
/* NOTE: this doesn't necessarily put PHY into low power mode,
* turning off its clock; that's a function of PHY integration and
* MUSB_POWER_ENSUSPEND. PHY may need a clock (sigh) to detect
* SE0 changing to connect (J) or wakeup (K) states.
*/
power = musb_readb(mbase, MUSB_POWER);
if (do_suspend) {
int retries = 10000;
if (power & MUSB_POWER_RESUME)
return -EBUSY;
if (!(power & MUSB_POWER_SUSPENDM)) {
power |= MUSB_POWER_SUSPENDM;
musb_writeb(mbase, MUSB_POWER, power);
/* Needed for OPT A tests */
power = musb_readb(mbase, MUSB_POWER);
while (power & MUSB_POWER_SUSPENDM) {
power = musb_readb(mbase, MUSB_POWER);
if (retries-- < 1)
break;
}
}
musb_dbg(musb, "Root port suspended, power %02x", power);
musb->port1_status |= USB_PORT_STAT_SUSPEND;
switch (musb_get_state(musb)) {
case OTG_STATE_A_HOST:
musb_set_state(musb, OTG_STATE_A_SUSPEND);
musb->is_active = musb->xceiv &&
musb->xceiv->otg->host->b_hnp_enable;
if (musb->is_active)
mod_timer(&musb->otg_timer, jiffies
+ msecs_to_jiffies(
OTG_TIME_A_AIDL_BDIS));
musb_platform_try_idle(musb, 0);
break;
case OTG_STATE_B_HOST:
musb_set_state(musb, OTG_STATE_B_WAIT_ACON);
musb->is_active = musb->xceiv &&
musb->xceiv->otg->host->b_hnp_enable;
musb_platform_try_idle(musb, 0);
break;
default:
musb_dbg(musb, "bogus rh suspend? %s",
musb_otg_state_string(musb));
}
} else if (power & MUSB_POWER_SUSPENDM) {
power &= ~MUSB_POWER_SUSPENDM;
power |= MUSB_POWER_RESUME;
musb_writeb(mbase, MUSB_POWER, power);
musb_dbg(musb, "Root port resuming, power %02x", power);
musb->port1_status |= MUSB_PORT_STAT_RESUME;
schedule_delayed_work(&musb->finish_resume_work,
msecs_to_jiffies(USB_RESUME_TIMEOUT));
}
return 0;
}
void musb_port_reset(struct musb *musb, bool do_reset)
{
u8 power;
void __iomem *mbase = musb->mregs;
if (musb_get_state(musb) == OTG_STATE_B_IDLE) {
musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
musb->port1_status &= ~USB_PORT_STAT_RESET;
return;
}
if (!is_host_active(musb))
return;
/* NOTE: caller guarantees it will turn off the reset when
* the appropriate amount of time has passed
*/
power = musb_readb(mbase, MUSB_POWER);
if (do_reset) {
/*
* If RESUME is set, we must make sure it stays minimum 20 ms.
* Then we must clear RESUME and wait a bit to let musb start
* generating SOFs. If we don't do this, OPT HS A 6.8 tests
* fail with "Error! Did not receive an SOF before suspend
* detected".
*/
if (power & MUSB_POWER_RESUME) {
long remain = (unsigned long) musb->rh_timer - jiffies;
if (musb->rh_timer > 0 && remain > 0) {
/* take into account the minimum delay after resume */
schedule_delayed_work(
&musb->deassert_reset_work, remain);
return;
}
musb_writeb(mbase, MUSB_POWER,
power & ~MUSB_POWER_RESUME);
/* Give the core 1 ms to clear MUSB_POWER_RESUME */
schedule_delayed_work(&musb->deassert_reset_work,
msecs_to_jiffies(1));
return;
}
power &= 0xf0;
musb_writeb(mbase, MUSB_POWER,
power | MUSB_POWER_RESET);
musb->port1_status |= USB_PORT_STAT_RESET;
musb->port1_status &= ~USB_PORT_STAT_ENABLE;
schedule_delayed_work(&musb->deassert_reset_work,
msecs_to_jiffies(50));
} else {
musb_dbg(musb, "root port reset stopped");
musb_platform_pre_root_reset_end(musb);
musb_writeb(mbase, MUSB_POWER,
power & ~MUSB_POWER_RESET);
musb_platform_post_root_reset_end(musb);
power = musb_readb(mbase, MUSB_POWER);
if (power & MUSB_POWER_HSMODE) {
musb_dbg(musb, "high-speed device connected");
musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
}
musb->port1_status &= ~USB_PORT_STAT_RESET;
musb->port1_status |= USB_PORT_STAT_ENABLE
| (USB_PORT_STAT_C_RESET << 16)
| (USB_PORT_STAT_C_ENABLE << 16);
usb_hcd_poll_rh_status(musb->hcd);
musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
}
}
void musb_root_disconnect(struct musb *musb)
{
musb->port1_status = USB_PORT_STAT_POWER
| (USB_PORT_STAT_C_CONNECTION << 16);
usb_hcd_poll_rh_status(musb->hcd);
musb->is_active = 0;
switch (musb_get_state(musb)) {
case OTG_STATE_A_SUSPEND:
if (musb->xceiv && musb->xceiv->otg->host->b_hnp_enable) {
musb_set_state(musb, OTG_STATE_A_PERIPHERAL);
musb->g.is_a_peripheral = 1;
break;
}
fallthrough;
case OTG_STATE_A_HOST:
musb_set_state(musb, OTG_STATE_A_WAIT_BCON);
musb->is_active = 0;
break;
case OTG_STATE_A_WAIT_VFALL:
musb_set_state(musb, OTG_STATE_B_IDLE);
break;
default:
musb_dbg(musb, "host disconnect (%s)",
musb_otg_state_string(musb));
}
}
EXPORT_SYMBOL_GPL(musb_root_disconnect);
/*---------------------------------------------------------------------*/
/* Caller may or may not hold musb->lock */
int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
{
struct musb *musb = hcd_to_musb(hcd);
int retval = 0;
/* called in_irq() via usb_hcd_poll_rh_status() */
if (musb->port1_status & 0xffff0000) {
*buf = 0x02;
retval = 1;
}
return retval;
}
static int musb_has_gadget(struct musb *musb)
{
/*
* In host-only mode we start a connection right away. In OTG mode
* we have to wait until we loaded a gadget. We don't really need a
* gadget if we operate as a host but we should not start a session
* as a device without a gadget or else we explode.
*/
#ifdef CONFIG_USB_MUSB_HOST
return 1;
#else
return musb->port_mode == MUSB_HOST;
#endif
}
int musb_hub_control(
struct usb_hcd *hcd,
u16 typeReq,
u16 wValue,
u16 wIndex,
char *buf,
u16 wLength)
{
struct musb *musb = hcd_to_musb(hcd);
u32 temp;
int retval = 0;
unsigned long flags;
bool start_musb = false;
spin_lock_irqsave(&musb->lock, flags);
if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
spin_unlock_irqrestore(&musb->lock, flags);
return -ESHUTDOWN;
}
/* hub features: always zero, setting is a NOP
* port features: reported, sometimes updated when host is active
* no indicators
*/
switch (typeReq) {
case ClearHubFeature:
case SetHubFeature:
switch (wValue) {
case C_HUB_OVER_CURRENT:
case C_HUB_LOCAL_POWER:
break;
default:
goto error;
}
break;
case ClearPortFeature:
if ((wIndex & 0xff) != 1)
goto error;
switch (wValue) {
case USB_PORT_FEAT_ENABLE:
break;
case USB_PORT_FEAT_SUSPEND:
musb_port_suspend(musb, false);
break;
case USB_PORT_FEAT_POWER:
if (!hcd->self.is_b_host)
musb_platform_set_vbus(musb, 0);
break;
case USB_PORT_FEAT_C_CONNECTION:
case USB_PORT_FEAT_C_ENABLE:
case USB_PORT_FEAT_C_OVER_CURRENT:
case USB_PORT_FEAT_C_RESET:
case USB_PORT_FEAT_C_SUSPEND:
break;
default:
goto error;
}
musb_dbg(musb, "clear feature %d", wValue);
musb->port1_status &= ~(1 << wValue);
break;
case GetHubDescriptor:
{
struct usb_hub_descriptor *desc = (void *)buf;
desc->bDescLength = 9;
desc->bDescriptorType = USB_DT_HUB;
desc->bNbrPorts = 1;
desc->wHubCharacteristics = cpu_to_le16(
HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
| HUB_CHAR_NO_OCPM /* no overcurrent reporting */
);
desc->bPwrOn2PwrGood = 5; /* msec/2 */
desc->bHubContrCurrent = 0;
/* workaround bogus struct definition */
desc->u.hs.DeviceRemovable[0] = 0x02; /* port 1 */
desc->u.hs.DeviceRemovable[1] = 0xff;
}
break;
case GetHubStatus:
temp = 0;
*(__le32 *) buf = cpu_to_le32(temp);
break;
case GetPortStatus:
if (wIndex != 1)
goto error;
put_unaligned(cpu_to_le32(musb->port1_status
& ~MUSB_PORT_STAT_RESUME),
(__le32 *) buf);
/* port change status is more interesting */
musb_dbg(musb, "port status %08x", musb->port1_status);
break;
case SetPortFeature:
if ((wIndex & 0xff) != 1)
goto error;
switch (wValue) {
case USB_PORT_FEAT_POWER:
/* NOTE: this controller has a strange state machine
* that involves "requesting sessions" according to
* magic side effects from incompletely-described
* rules about startup...
*
* This call is what really starts the host mode; be
* very careful about side effects if you reorder any
* initialization logic, e.g. for OTG, or change any
* logic relating to VBUS power-up.
*/
if (!hcd->self.is_b_host && musb_has_gadget(musb))
start_musb = true;
break;
case USB_PORT_FEAT_RESET:
musb_port_reset(musb, true);
break;
case USB_PORT_FEAT_SUSPEND:
musb_port_suspend(musb, true);
break;
case USB_PORT_FEAT_TEST:
if (unlikely(is_host_active(musb)))
goto error;
wIndex >>= 8;
switch (wIndex) {
case USB_TEST_J:
pr_debug("USB_TEST_J\n");
temp = MUSB_TEST_J;
break;
case USB_TEST_K:
pr_debug("USB_TEST_K\n");
temp = MUSB_TEST_K;
break;
case USB_TEST_SE0_NAK:
pr_debug("USB_TEST_SE0_NAK\n");
temp = MUSB_TEST_SE0_NAK;
break;
case USB_TEST_PACKET:
pr_debug("USB_TEST_PACKET\n");
temp = MUSB_TEST_PACKET;
musb_load_testpacket(musb);
break;
case USB_TEST_FORCE_ENABLE:
pr_debug("USB_TEST_FORCE_ENABLE\n");
temp = MUSB_TEST_FORCE_HOST
| MUSB_TEST_FORCE_HS;
musb_writeb(musb->mregs, MUSB_DEVCTL,
MUSB_DEVCTL_SESSION);
break;
case 6:
pr_debug("TEST_FIFO_ACCESS\n");
temp = MUSB_TEST_FIFO_ACCESS;
break;
default:
goto error;
}
musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
break;
default:
goto error;
}
musb_dbg(musb, "set feature %d", wValue);
musb->port1_status |= 1 << wValue;
break;
default:
error:
/* "protocol stall" on error */
retval = -EPIPE;
}
spin_unlock_irqrestore(&musb->lock, flags);
if (start_musb)
musb_start(musb);
return retval;
}