/*
 * otg.c - ChipIdea USB IP core OTG driver
 *
 * Copyright (C) 2013 Freescale Semiconductor, Inc.
 *
 * Author: Peter Chen
 *
 * 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.
 */

/*
 * This file mainly handles otgsc register, OTG fsm operations for HNP and SRP
 * are also included.
 */

#include <linux/usb/otg.h>
#include <linux/usb/gadget.h>
#include <linux/usb/chipidea.h>

#include "ci.h"
#include "bits.h"
#include "otg.h"
#include "otg_fsm.h"

/**
 * hw_read_otgsc returns otgsc register bits value.
 * @mask: bitfield mask
 */
u32 hw_read_otgsc(struct ci_hdrc *ci, u32 mask)
{
	struct ci_hdrc_cable *cable;
	u32 val = hw_read(ci, OP_OTGSC, mask);

	/*
	 * If using extcon framework for VBUS and/or ID signal
	 * detection overwrite OTGSC register value
	 */
	cable = &ci->platdata->vbus_extcon;
	if (!IS_ERR(cable->edev)) {
		if (cable->changed)
			val |= OTGSC_BSVIS;
		else
			val &= ~OTGSC_BSVIS;

		cable->changed = false;

		if (cable->state)
			val |= OTGSC_BSV;
		else
			val &= ~OTGSC_BSV;
	}

	cable = &ci->platdata->id_extcon;
	if (!IS_ERR(cable->edev)) {
		if (cable->changed)
			val |= OTGSC_IDIS;
		else
			val &= ~OTGSC_IDIS;

		cable->changed = false;

		if (cable->state)
			val |= OTGSC_ID;
		else
			val &= ~OTGSC_ID;
	}

	return val;
}

/**
 * hw_write_otgsc updates target bits of OTGSC register.
 * @mask: bitfield mask
 * @data: to be written
 */
void hw_write_otgsc(struct ci_hdrc *ci, u32 mask, u32 data)
{
	hw_write(ci, OP_OTGSC, mask | OTGSC_INT_STATUS_BITS, data);
}

/**
 * ci_otg_role - pick role based on ID pin state
 * @ci: the controller
 */
enum ci_role ci_otg_role(struct ci_hdrc *ci)
{
	enum ci_role role = hw_read_otgsc(ci, OTGSC_ID)
		? CI_ROLE_GADGET
		: CI_ROLE_HOST;

	return role;
}

void ci_handle_vbus_change(struct ci_hdrc *ci)
{
	if (!ci->is_otg)
		return;

	if (hw_read_otgsc(ci, OTGSC_BSV))
		usb_gadget_vbus_connect(&ci->gadget);
	else
		usb_gadget_vbus_disconnect(&ci->gadget);
}

#define CI_VBUS_STABLE_TIMEOUT_MS 5000
static void ci_handle_id_switch(struct ci_hdrc *ci)
{
	enum ci_role role = ci_otg_role(ci);

	if (role != ci->role) {
		dev_dbg(ci->dev, "switching from %s to %s\n",
			ci_role(ci)->name, ci->roles[role]->name);

		ci_role_stop(ci);

		if (role == CI_ROLE_GADGET)
			/* wait vbus lower than OTGSC_BSV */
			hw_wait_reg(ci, OP_OTGSC, OTGSC_BSV, 0,
					CI_VBUS_STABLE_TIMEOUT_MS);

		ci_role_start(ci, role);
	}
}
/**
 * ci_otg_work - perform otg (vbus/id) event handle
 * @work: work struct
 */
static void ci_otg_work(struct work_struct *work)
{
	struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);

	if (ci_otg_is_fsm_mode(ci) && !ci_otg_fsm_work(ci)) {
		enable_irq(ci->irq);
		return;
	}

	pm_runtime_get_sync(ci->dev);
	if (ci->id_event) {
		ci->id_event = false;
		ci_handle_id_switch(ci);
	} else if (ci->b_sess_valid_event) {
		ci->b_sess_valid_event = false;
		ci_handle_vbus_change(ci);
	} else
		dev_err(ci->dev, "unexpected event occurs at %s\n", __func__);
	pm_runtime_put_sync(ci->dev);

	enable_irq(ci->irq);
}


/**
 * ci_hdrc_otg_init - initialize otg struct
 * ci: the controller
 */
int ci_hdrc_otg_init(struct ci_hdrc *ci)
{
	INIT_WORK(&ci->work, ci_otg_work);
	ci->wq = create_freezable_workqueue("ci_otg");
	if (!ci->wq) {
		dev_err(ci->dev, "can't create workqueue\n");
		return -ENODEV;
	}

	if (ci_otg_is_fsm_mode(ci))
		return ci_hdrc_otg_fsm_init(ci);

	return 0;
}

/**
 * ci_hdrc_otg_destroy - destroy otg struct
 * ci: the controller
 */
void ci_hdrc_otg_destroy(struct ci_hdrc *ci)
{
	if (ci->wq) {
		flush_workqueue(ci->wq);
		destroy_workqueue(ci->wq);
	}
	/* Disable all OTG irq and clear status */
	hw_write_otgsc(ci, OTGSC_INT_EN_BITS | OTGSC_INT_STATUS_BITS,
						OTGSC_INT_STATUS_BITS);
	if (ci_otg_is_fsm_mode(ci))
		ci_hdrc_otg_fsm_remove(ci);
}
class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2017-01-30 14:28:22 -0800</td></tr>
<tr><th>committer</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2017-01-30 14:28:22 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/fs/xfs/xfs_trace.c?id=54791b276b4000b307339f269d3bf7db877d536f'>54791b276b4000b307339f269d3bf7db877d536f</a> (<a href='/cgit.cgi/linux/net-next.git/patch/fs/xfs/xfs_trace.c?id=54791b276b4000b307339f269d3bf7db877d536f'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=54791b276b4000b307339f269d3bf7db877d536f'>1c2616bd373ce5ea28aac2a53e32f5b5834901ce</a> /<a href='/cgit.cgi/linux/net-next.git/tree/fs/xfs/xfs_trace.c?id=54791b276b4000b307339f269d3bf7db877d536f'>fs/xfs/xfs_trace.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/fs/xfs/xfs_trace.c?id=5d0e7705774dd412a465896d08d59a81a345c1e4'>5d0e7705774dd412a465896d08d59a81a345c1e4</a> (<a href='/cgit.cgi/linux/net-next.git/diff/fs/xfs/xfs_trace.c?id=54791b276b4000b307339f269d3bf7db877d536f&amp;id2=5d0e7705774dd412a465896d08d59a81a345c1e4'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/fs/xfs/xfs_trace.c?id=047487241ff59374fded8c477f21453681f5995c'>047487241ff59374fded8c477f21453681f5995c</a> (<a href='/cgit.cgi/linux/net-next.git/diff/fs/xfs/xfs_trace.c?id=54791b276b4000b307339f269d3bf7db877d536f&amp;id2=047487241ff59374fded8c477f21453681f5995c'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'sparc64-non-resumable-user-error-recovery'</div><div class='commit-msg'>Liam R. Howlett says:

====================
sparc64: Recover from userspace non-resumable PIO &amp; MEM errors

A non-resumable error from userspace is able to cause a kernel panic or trap
loop due to the setup and handling of the queued traps once in the kernel.
This patch series addresses both of these issues.

The queues are fixed by simply zeroing the memory before use.

PIO errors from userspace will result in a SIGBUS being sent to the user
process.

The MEM errors form userspace will result in a SIGKILL and also cause the
offending pages to be claimed so they are no longer used in future tasks.
SIGKILL is used to ensure that the process does not try to coredump and result
in an attempt to read the memory again from within kernel space.  Although
there is a HV call to scrub the memory (mem_scrub), there is no easy way to
guarantee that the real memory address(es) are not used by other tasks.
Clearing the error with mem_scrub would zero the memory and cause the other
processes to proceed with bad data.

The handling of other non-resumable errors remain unchanged and will cause a
panic.
====================

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=54791b276b4000b307339f269d3bf7db877d536f'>Diffstat</a> (limited to 'fs/xfs/xfs_trace.c')</div><table summary='diffstat' class='diffstat'>