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// SPDX-License-Identifier: GPL-2.0+
/*
* PCI Express Hot Plug Controller Driver
*
* Copyright (C) 1995,2001 Compaq Computer Corporation
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2001 IBM Corp.
* Copyright (C) 2003-2004 Intel Corporation
*
* All rights reserved.
*
* Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/pci.h>
#include "../pci.h"
#include "pciehp.h"
/* The following routines constitute the bulk of the
hotplug controller logic
*/
static void set_slot_off(struct controller *ctrl, struct slot *pslot)
{
/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
if (POWER_CTRL(ctrl)) {
pciehp_power_off_slot(pslot);
/*
* After turning power off, we must wait for at least 1 second
* before taking any action that relies on power having been
* removed from the slot/adapter.
*/
msleep(1000);
}
pciehp_green_led_off(pslot);
pciehp_set_attention_status(pslot, 1);
}
/**
* board_added - Called after a board has been added to the system.
* @p_slot: &slot where board is added
*
* Turns power on for the board.
* Configures board.
*/
static int board_added(struct slot *p_slot)
{
int retval = 0;
struct controller *ctrl = p_slot->ctrl;
struct pci_bus *parent = ctrl->pcie->port->subordinate;
if (POWER_CTRL(ctrl)) {
/* Power on slot */
retval = pciehp_power_on_slot(p_slot);
if (retval)
return retval;
}
pciehp_green_led_blink(p_slot);
/* Check link training status */
retval = pciehp_check_link_status(ctrl);
if (retval) {
ctrl_err(ctrl, "Failed to check link status\n");
goto err_exit;
}
/* Check for a power fault */
if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(p_slot));
retval = -EIO;
goto err_exit;
}
retval = pciehp_configure_device(p_slot);
if (retval) {
if (retval != -EEXIST) {
ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
pci_domain_nr(parent), parent->number);
goto err_exit;
}
}
pciehp_green_led_on(p_slot);
pciehp_set_attention_status(p_slot, 0);
return 0;
err_exit:
set_slot_off(ctrl, p_slot);
return retval;
}
/**
* remove_board - Turns off slot and LEDs
* @p_slot: slot where board is being removed
*/
static void remove_board(struct slot *p_slot)
{
struct controller *ctrl = p_slot->ctrl;
pciehp_unconfigure_device(p_slot);
if (POWER_CTRL(ctrl)) {
pciehp_power_off_slot(p_slot);
/*
* After turning power off, we must wait for at least 1 second
* before taking any action that relies on power having been
* removed from the slot/adapter.
*/
msleep(1000);
}
/* turn off Green LED */
pciehp_green_led_off(p_slot);
}
static int pciehp_enable_slot(struct slot *slot);
static int pciehp_disable_slot(struct slot *slot);
void pciehp_request(struct controller *ctrl, int action)
{
atomic_or(action, &ctrl->pending_events);
if (!pciehp_poll_mode)
irq_wake_thread(ctrl->pcie->irq, ctrl);
}
void pciehp_queue_pushbutton_work(struct work_struct *work)
{
struct slot *p_slot = container_of(work, struct slot, work.work);
struct controller *ctrl = p_slot->ctrl;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case BLINKINGOFF_STATE:
pciehp_request(ctrl, DISABLE_SLOT);
break;
case BLINKINGON_STATE:
pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
break;
default:
break;
}
mutex_unlock(&p_slot->lock);
}
void pciehp_handle_button_press(struct slot *p_slot)
{
struct controller *ctrl = p_slot->ctrl;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case OFF_STATE:
case ON_STATE:
if (p_slot->state == ON_STATE) {
p_slot->state = BLINKINGOFF_STATE;
ctrl_info(ctrl, "Slot(%s): Powering off due to button press\n",
slot_name(p_slot));
} else {
p_slot->state = BLINKINGON_STATE;
ctrl_info(ctrl, "Slot(%s) Powering on due to button press\n",
slot_name(p_slot));
}
/* blink green LED and turn off amber */
pciehp_green_led_blink(p_slot);
pciehp_set_attention_status(p_slot, 0);
schedule_delayed_work(&p_slot->work, 5 * HZ);
break;
case BLINKINGOFF_STATE:
case BLINKINGON_STATE:
/*
* Cancel if we are still blinking; this means that we
* press the attention again before the 5 sec. limit
* expires to cancel hot-add or hot-remove
*/
ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(p_slot));
cancel_delayed_work(&p_slot->work);
if (p_slot->state == BLINKINGOFF_STATE) {
p_slot->state = ON_STATE;
pciehp_green_led_on(p_slot);
} else {
p_slot->state = OFF_STATE;
pciehp_green_led_off(p_slot);
}
pciehp_set_attention_status(p_slot, 0);
ctrl_info(ctrl, "Slot(%s): Action canceled due to button press\n",
slot_name(p_slot));
break;
default:
ctrl_err(ctrl, "Slot(%s): Ignoring invalid state %#x\n",
slot_name(p_slot), p_slot->state);
break;
}
mutex_unlock(&p_slot->lock);
}
void pciehp_handle_disable_request(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
mutex_lock(&slot->lock);
switch (slot->state) {
case BLINKINGON_STATE:
case BLINKINGOFF_STATE:
cancel_delayed_work(&slot->work);
break;
}
slot->state = POWEROFF_STATE;
mutex_unlock(&slot->lock);
ctrl->request_result = pciehp_disable_slot(slot);
}
void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events)
{
struct controller *ctrl = slot->ctrl;
bool link_active;
u8 present;
/*
* If the slot is on and presence or link has changed, turn it off.
* Even if it's occupied again, we cannot assume the card is the same.
*/
mutex_lock(&slot->lock);
switch (slot->state) {
case BLINKINGOFF_STATE:
cancel_delayed_work(&slot->work);
/* fall through */
case ON_STATE:
slot->state = POWEROFF_STATE;
mutex_unlock(&slot->lock);
if (events & PCI_EXP_SLTSTA_DLLSC)
ctrl_info(ctrl, "Slot(%s): Link Down\n",
slot_name(slot));
if (events & PCI_EXP_SLTSTA_PDC)
ctrl_info(ctrl, "Slot(%s): Card not present\n",
slot_name(slot));
pciehp_disable_slot(slot);
break;
default:
mutex_unlock(&slot->lock);
break;
}
/* Turn the slot on if it's occupied or link is up */
mutex_lock(&slot->lock);
pciehp_get_adapter_status(slot, &present);
link_active = pciehp_check_link_active(ctrl);
if (!present && !link_active) {
mutex_unlock(&slot->lock);
return;
}
switch (slot->state) {
case BLINKINGON_STATE:
cancel_delayed_work(&slot->work);
/* fall through */
case OFF_STATE:
slot->state = POWERON_STATE;
mutex_unlock(&slot->lock);
if (present)
ctrl_info(ctrl, "Slot(%s): Card present\n",
slot_name(slot));
if (link_active)
ctrl_info(ctrl, "Slot(%s): Link Up\n",
slot_name(slot));
ctrl->request_result = pciehp_enable_slot(slot);
break;
default:
mutex_unlock(&slot->lock);
break;
}
}
static int __pciehp_enable_slot(struct slot *p_slot)
{
u8 getstatus = 0;
struct controller *ctrl = p_slot->ctrl;
pciehp_get_adapter_status(p_slot, &getstatus);
if (!getstatus) {
ctrl_info(ctrl, "Slot(%s): No adapter\n", slot_name(p_slot));
return -ENODEV;
}
if (MRL_SENS(p_slot->ctrl)) {
pciehp_get_latch_status(p_slot, &getstatus);
if (getstatus) {
ctrl_info(ctrl, "Slot(%s): Latch open\n",
slot_name(p_slot));
return -ENODEV;
}
}
if (POWER_CTRL(p_slot->ctrl)) {
pciehp_get_power_status(p_slot, &getstatus);
if (getstatus) {
ctrl_info(ctrl, "Slot(%s): Already enabled\n",
slot_name(p_slot));
return 0;
}
}
return board_added(p_slot);
}
static int pciehp_enable_slot(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
int ret;
pm_runtime_get_sync(&ctrl->pcie->port->dev);
ret = __pciehp_enable_slot(slot);
if (ret && ATTN_BUTTN(ctrl))
pciehp_green_led_off(slot); /* may be blinking */
pm_runtime_put(&ctrl->pcie->port->dev);
mutex_lock(&slot->lock);
slot->state = ret ? OFF_STATE : ON_STATE;
mutex_unlock(&slot->lock);
return ret;
}
static int __pciehp_disable_slot(struct slot *p_slot)
{
u8 getstatus = 0;
struct controller *ctrl = p_slot->ctrl;
if (POWER_CTRL(p_slot->ctrl)) {
pciehp_get_power_status(p_slot, &getstatus);
if (!getstatus) {
ctrl_info(ctrl, "Slot(%s): Already disabled\n",
slot_name(p_slot));
return -EINVAL;
}
}
remove_board(p_slot);
return 0;
}
static int pciehp_disable_slot(struct slot *slot)
{
struct controller *ctrl = slot->ctrl;
int ret;
pm_runtime_get_sync(&ctrl->pcie->port->dev);
ret = __pciehp_disable_slot(slot);
pm_runtime_put(&ctrl->pcie->port->dev);
mutex_lock(&slot->lock);
slot->state = OFF_STATE;
mutex_unlock(&slot->lock);
return ret;
}
int pciehp_sysfs_enable_slot(struct slot *p_slot)
{
struct controller *ctrl = p_slot->ctrl;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case BLINKINGON_STATE:
case OFF_STATE:
mutex_unlock(&p_slot->lock);
/*
* The IRQ thread becomes a no-op if the user pulls out the
* card before the thread wakes up, so initialize to -ENODEV.
*/
ctrl->request_result = -ENODEV;
pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
wait_event(ctrl->requester,
!atomic_read(&ctrl->pending_events));
return ctrl->request_result;
case POWERON_STATE:
ctrl_info(ctrl, "Slot(%s): Already in powering on state\n",
slot_name(p_slot));
break;
case BLINKINGOFF_STATE:
case ON_STATE:
case POWEROFF_STATE:
ctrl_info(ctrl, "Slot(%s): Already enabled\n",
slot_name(p_slot));
break;
default:
ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
slot_name(p_slot), p_slot->state);
break;
}
mutex_unlock(&p_slot->lock);
return -ENODEV;
}
int pciehp_sysfs_disable_slot(struct slot *p_slot)
{
struct controller *ctrl = p_slot->ctrl;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case BLINKINGOFF_STATE:
case ON_STATE:
mutex_unlock(&p_slot->lock);
pciehp_request(ctrl, DISABLE_SLOT);
wait_event(ctrl->requester,
!atomic_read(&ctrl->pending_events));
return ctrl->request_result;
case POWEROFF_STATE:
ctrl_info(ctrl, "Slot(%s): Already in powering off state\n",
slot_name(p_slot));
break;
case BLINKINGON_STATE:
case OFF_STATE:
case POWERON_STATE:
ctrl_info(ctrl, "Slot(%s): Already disabled\n",
slot_name(p_slot));
break;
default:
ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
slot_name(p_slot), p_slot->state);
break;
}
mutex_unlock(&p_slot->lock);
return -ENODEV;
}