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linux/drivers/pci/hotplug/shpchp_ctrl.c
Lukas Wunner a7da21613c PCI: hotplug: Drop hotplug_slot_info 
Ever since the PCI hotplug core was introduced in 2002, drivers had to
allocate and register a struct hotplug_slot_info for every slot:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Apparently the idea was that drivers furnish the hotplug core with an
up-to-date card presence status, power status, latch status and
attention indicator status as well as notify the hotplug core of changes
thereof.  However only 4 out of 12 hotplug drivers bother to notify the
hotplug core with pci_hp_change_slot_info() and the hotplug core never
made any use of the information:  There is just a single macro in
pci_hotplug_core.c, GET_STATUS(), which uses the hotplug_slot_info if
the driver lacks the corresponding callback in hotplug_slot_ops.  The
macro is called when the user reads the attribute via sysfs.

Now, if the callback isn't defined, the attribute isn't exposed in sysfs
in the first place (see e.g. has_power_file()).  There are only two
situations when the hotplug_slot_info would actually be accessed:

* If the driver defines ->enable_slot or ->disable_slot but not
  ->get_power_status.

* If the driver defines ->set_attention_status but not
  ->get_attention_status.

There is no driver doing the former and just a single driver doing the
latter, namely pnv_php.c.  Amend it with a ->get_attention_status
callback.  With that, the hotplug_slot_info becomes completely unused by
the PCI hotplug core.  But a few drivers use it internally as a cache:

cpcihp uses it to cache the latch_status and adapter_status.
cpqhp uses it to cache the adapter_status.
pnv_php and rpaphp use it to cache the attention_status.
shpchp uses it to cache all four values.

Amend these drivers to cache the information in their private slot
struct.  shpchp's slot struct already contains members to cache the
power_status and adapter_status, so additional members are only needed
for the other two values.  In the case of cpqphp, the cached value is
only accessed in a single place, so instead of caching it, read the
current value from the hardware.

Caution:  acpiphp, cpci, cpqhp, shpchp, asus-wmi and eeepc-laptop
populate the hotplug_slot_info with initial values on probe.  That code
is herewith removed.  There is a theoretical chance that the code has
side effects without which the driver fails to function, e.g. if the
ACPI method to read the adapter status needs to be executed at least
once on probe.  That seems unlikely to me, still maintainers should
review the changes carefully for this possibility.

Rafael adds: "I'm not aware of any case in which it will break anything,
[...] but if that happens, it may be necessary to add the execution of
the control methods in question directly to the initialization part."

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>  # drivers/pci/hotplug/rpa*
Acked-by: Sebastian Ott <sebott@linux.ibm.com>        # drivers/pci/hotplug/s390*
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
2018-09-18 17:52:15 -05:00

708 lines
18 KiB
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// SPDX-License-Identifier: GPL-2.0+
/*
* Standard 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/pci.h>
#include "../pci.h"
#include "shpchp.h"
static void interrupt_event_handler(struct work_struct *work);
static int shpchp_enable_slot(struct slot *p_slot);
static int shpchp_disable_slot(struct slot *p_slot);
static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
{
struct event_info *info;
info = kmalloc(sizeof(*info), GFP_ATOMIC);
if (!info)
return -ENOMEM;
info->event_type = event_type;
info->p_slot = p_slot;
INIT_WORK(&info->work, interrupt_event_handler);
queue_work(p_slot->wq, &info->work);
return 0;
}
u8 shpchp_handle_attention_button(u8 hp_slot, struct controller *ctrl)
{
struct slot *p_slot;
u32 event_type;
/* Attention Button Change */
ctrl_dbg(ctrl, "Attention button interrupt received\n");
p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
/*
* Button pressed - See if need to TAKE ACTION!!!
*/
ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
event_type = INT_BUTTON_PRESS;
queue_interrupt_event(p_slot, event_type);
return 0;
}
u8 shpchp_handle_switch_change(u8 hp_slot, struct controller *ctrl)
{
struct slot *p_slot;
u8 getstatus;
u32 event_type;
/* Switch Change */
ctrl_dbg(ctrl, "Switch interrupt received\n");
p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
ctrl_dbg(ctrl, "Card present %x Power status %x\n",
p_slot->presence_save, p_slot->pwr_save);
if (getstatus) {
/*
* Switch opened
*/
ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
event_type = INT_SWITCH_OPEN;
if (p_slot->pwr_save && p_slot->presence_save) {
event_type = INT_POWER_FAULT;
ctrl_err(ctrl, "Surprise Removal of card\n");
}
} else {
/*
* Switch closed
*/
ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
event_type = INT_SWITCH_CLOSE;
}
queue_interrupt_event(p_slot, event_type);
return 1;
}
u8 shpchp_handle_presence_change(u8 hp_slot, struct controller *ctrl)
{
struct slot *p_slot;
u32 event_type;
/* Presence Change */
ctrl_dbg(ctrl, "Presence/Notify input change\n");
p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
/*
* Save the presence state
*/
p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
if (p_slot->presence_save) {
/*
* Card Present
*/
ctrl_info(ctrl, "Card present on Slot(%s)\n",
slot_name(p_slot));
event_type = INT_PRESENCE_ON;
} else {
/*
* Not Present
*/
ctrl_info(ctrl, "Card not present on Slot(%s)\n",
slot_name(p_slot));
event_type = INT_PRESENCE_OFF;
}
queue_interrupt_event(p_slot, event_type);
return 1;
}
u8 shpchp_handle_power_fault(u8 hp_slot, struct controller *ctrl)
{
struct slot *p_slot;
u32 event_type;
/* Power fault */
ctrl_dbg(ctrl, "Power fault interrupt received\n");
p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
if (!(p_slot->hpc_ops->query_power_fault(p_slot))) {
/*
* Power fault Cleared
*/
ctrl_info(ctrl, "Power fault cleared on Slot(%s)\n",
slot_name(p_slot));
p_slot->status = 0x00;
event_type = INT_POWER_FAULT_CLEAR;
} else {
/*
* Power fault
*/
ctrl_info(ctrl, "Power fault on Slot(%s)\n", slot_name(p_slot));
event_type = INT_POWER_FAULT;
/* set power fault status for this board */
p_slot->status = 0xFF;
ctrl_info(ctrl, "Power fault bit %x set\n", hp_slot);
}
queue_interrupt_event(p_slot, event_type);
return 1;
}
/* The following routines constitute the bulk of the
hotplug controller logic
*/
static int change_bus_speed(struct controller *ctrl, struct slot *p_slot,
enum pci_bus_speed speed)
{
int rc = 0;
ctrl_dbg(ctrl, "Change speed to %d\n", speed);
rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, speed);
if (rc) {
ctrl_err(ctrl, "%s: Issue of set bus speed mode command failed\n",
__func__);
return WRONG_BUS_FREQUENCY;
}
return rc;
}
static int fix_bus_speed(struct controller *ctrl, struct slot *pslot,
u8 flag, enum pci_bus_speed asp, enum pci_bus_speed bsp,
enum pci_bus_speed msp)
{
int rc = 0;
/*
* If other slots on the same bus are occupied, we cannot
* change the bus speed.
*/
if (flag) {
if (asp < bsp) {
ctrl_err(ctrl, "Speed of bus %x and adapter %x mismatch\n",
bsp, asp);
rc = WRONG_BUS_FREQUENCY;
}
return rc;
}
if (asp < msp) {
if (bsp != asp)
rc = change_bus_speed(ctrl, pslot, asp);
} else {
if (bsp != msp)
rc = change_bus_speed(ctrl, pslot, msp);
}
return rc;
}
/**
* board_added - Called after a board has been added to the system.
* @p_slot: target &slot
*
* Turns power on for the board.
* Configures board.
*/
static int board_added(struct slot *p_slot)
{
u8 hp_slot;
u8 slots_not_empty = 0;
int rc = 0;
enum pci_bus_speed asp, bsp, msp;
struct controller *ctrl = p_slot->ctrl;
struct pci_bus *parent = ctrl->pci_dev->subordinate;
hp_slot = p_slot->device - ctrl->slot_device_offset;
ctrl_dbg(ctrl, "%s: p_slot->device, slot_offset, hp_slot = %d, %d ,%d\n",
__func__, p_slot->device, ctrl->slot_device_offset, hp_slot);
/* Power on slot without connecting to bus */
rc = p_slot->hpc_ops->power_on_slot(p_slot);
if (rc) {
ctrl_err(ctrl, "Failed to power on slot\n");
return -1;
}
if ((ctrl->pci_dev->vendor == 0x8086) && (ctrl->pci_dev->device == 0x0332)) {
rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, PCI_SPEED_33MHz);
if (rc) {
ctrl_err(ctrl, "%s: Issue of set bus speed mode command failed\n",
__func__);
return WRONG_BUS_FREQUENCY;
}
/* turn on board, blink green LED, turn off Amber LED */
rc = p_slot->hpc_ops->slot_enable(p_slot);
if (rc) {
ctrl_err(ctrl, "Issue of Slot Enable command failed\n");
return rc;
}
}
rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &asp);
if (rc) {
ctrl_err(ctrl, "Can't get adapter speed or bus mode mismatch\n");
return WRONG_BUS_FREQUENCY;
}
bsp = ctrl->pci_dev->subordinate->cur_bus_speed;
msp = ctrl->pci_dev->subordinate->max_bus_speed;
/* Check if there are other slots or devices on the same bus */
if (!list_empty(&ctrl->pci_dev->subordinate->devices))
slots_not_empty = 1;
ctrl_dbg(ctrl, "%s: slots_not_empty %d, adapter_speed %d, bus_speed %d, max_bus_speed %d\n",
__func__, slots_not_empty, asp,
bsp, msp);
rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, asp, bsp, msp);
if (rc)
return rc;
/* turn on board, blink green LED, turn off Amber LED */
rc = p_slot->hpc_ops->slot_enable(p_slot);
if (rc) {
ctrl_err(ctrl, "Issue of Slot Enable command failed\n");
return rc;
}
/* Wait for ~1 second */
msleep(1000);
ctrl_dbg(ctrl, "%s: slot status = %x\n", __func__, p_slot->status);
/* Check for a power fault */
if (p_slot->status == 0xFF) {
/* power fault occurred, but it was benign */
ctrl_dbg(ctrl, "%s: Power fault\n", __func__);
rc = POWER_FAILURE;
p_slot->status = 0;
goto err_exit;
}
if (shpchp_configure_device(p_slot)) {
ctrl_err(ctrl, "Cannot add device at %04x:%02x:%02x\n",
pci_domain_nr(parent), p_slot->bus, p_slot->device);
goto err_exit;
}
p_slot->status = 0;
p_slot->is_a_board = 0x01;
p_slot->pwr_save = 1;
p_slot->hpc_ops->green_led_on(p_slot);
return 0;
err_exit:
/* turn off slot, turn on Amber LED, turn off Green LED */
rc = p_slot->hpc_ops->slot_disable(p_slot);
if (rc) {
ctrl_err(ctrl, "%s: Issue of Slot Disable command failed\n",
__func__);
return rc;
}
return(rc);
}
/**
* remove_board - Turns off slot and LEDs
* @p_slot: target &slot
*/
static int remove_board(struct slot *p_slot)
{
struct controller *ctrl = p_slot->ctrl;
u8 hp_slot;
int rc;
if (shpchp_unconfigure_device(p_slot))
return(1);
hp_slot = p_slot->device - ctrl->slot_device_offset;
p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
ctrl_dbg(ctrl, "%s: hp_slot = %d\n", __func__, hp_slot);
/* Change status to shutdown */
if (p_slot->is_a_board)
p_slot->status = 0x01;
/* turn off slot, turn on Amber LED, turn off Green LED */
rc = p_slot->hpc_ops->slot_disable(p_slot);
if (rc) {
ctrl_err(ctrl, "%s: Issue of Slot Disable command failed\n",
__func__);
return rc;
}
rc = p_slot->hpc_ops->set_attention_status(p_slot, 0);
if (rc) {
ctrl_err(ctrl, "Issue of Set Attention command failed\n");
return rc;
}
p_slot->pwr_save = 0;
p_slot->is_a_board = 0;
return 0;
}
struct pushbutton_work_info {
struct slot *p_slot;
struct work_struct work;
};
/**
* shpchp_pushbutton_thread - handle pushbutton events
* @work: &struct work_struct to be handled
*
* Scheduled procedure to handle blocking stuff for the pushbuttons.
* Handles all pending events and exits.
*/
static void shpchp_pushbutton_thread(struct work_struct *work)
{
struct pushbutton_work_info *info =
container_of(work, struct pushbutton_work_info, work);
struct slot *p_slot = info->p_slot;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case POWEROFF_STATE:
mutex_unlock(&p_slot->lock);
shpchp_disable_slot(p_slot);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
break;
case POWERON_STATE:
mutex_unlock(&p_slot->lock);
if (shpchp_enable_slot(p_slot))
p_slot->hpc_ops->green_led_off(p_slot);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
break;
default:
break;
}
mutex_unlock(&p_slot->lock);
kfree(info);
}
void shpchp_queue_pushbutton_work(struct work_struct *work)
{
struct slot *p_slot = container_of(work, struct slot, work.work);
struct pushbutton_work_info *info;
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
__func__);
return;
}
info->p_slot = p_slot;
INIT_WORK(&info->work, shpchp_pushbutton_thread);
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case BLINKINGOFF_STATE:
p_slot->state = POWEROFF_STATE;
break;
case BLINKINGON_STATE:
p_slot->state = POWERON_STATE;
break;
default:
kfree(info);
goto out;
}
queue_work(p_slot->wq, &info->work);
out:
mutex_unlock(&p_slot->lock);
}
static void update_slot_info(struct slot *slot)
{
slot->hpc_ops->get_power_status(slot, &slot->pwr_save);
slot->hpc_ops->get_attention_status(slot, &slot->attention_save);
slot->hpc_ops->get_latch_status(slot, &slot->latch_save);
slot->hpc_ops->get_adapter_status(slot, &slot->presence_save);
}
/*
* Note: This function must be called with slot->lock held
*/
static void handle_button_press_event(struct slot *p_slot)
{
u8 getstatus;
struct controller *ctrl = p_slot->ctrl;
switch (p_slot->state) {
case STATIC_STATE:
p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
if (getstatus) {
p_slot->state = BLINKINGOFF_STATE;
ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
slot_name(p_slot));
} else {
p_slot->state = BLINKINGON_STATE;
ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
slot_name(p_slot));
}
/* blink green LED and turn off amber */
p_slot->hpc_ops->green_led_blink(p_slot);
p_slot->hpc_ops->set_attention_status(p_slot, 0);
queue_delayed_work(p_slot->wq, &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, "Button cancel on Slot(%s)\n",
slot_name(p_slot));
cancel_delayed_work(&p_slot->work);
if (p_slot->state == BLINKINGOFF_STATE)
p_slot->hpc_ops->green_led_on(p_slot);
else
p_slot->hpc_ops->green_led_off(p_slot);
p_slot->hpc_ops->set_attention_status(p_slot, 0);
ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
slot_name(p_slot));
p_slot->state = STATIC_STATE;
break;
case POWEROFF_STATE:
case POWERON_STATE:
/*
* Ignore if the slot is on power-on or power-off state;
* this means that the previous attention button action
* to hot-add or hot-remove is undergoing
*/
ctrl_info(ctrl, "Button ignore on Slot(%s)\n",
slot_name(p_slot));
update_slot_info(p_slot);
break;
default:
ctrl_warn(ctrl, "Not a valid state\n");
break;
}
}
static void interrupt_event_handler(struct work_struct *work)
{
struct event_info *info = container_of(work, struct event_info, work);
struct slot *p_slot = info->p_slot;
mutex_lock(&p_slot->lock);
switch (info->event_type) {
case INT_BUTTON_PRESS:
handle_button_press_event(p_slot);
break;
case INT_POWER_FAULT:
ctrl_dbg(p_slot->ctrl, "%s: Power fault\n", __func__);
p_slot->hpc_ops->set_attention_status(p_slot, 1);
p_slot->hpc_ops->green_led_off(p_slot);
break;
default:
update_slot_info(p_slot);
break;
}
mutex_unlock(&p_slot->lock);
kfree(info);
}
static int shpchp_enable_slot (struct slot *p_slot)
{
u8 getstatus = 0;
int rc, retval = -ENODEV;
struct controller *ctrl = p_slot->ctrl;
/* Check to see if (latch closed, card present, power off) */
mutex_lock(&p_slot->ctrl->crit_sect);
rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
if (rc || !getstatus) {
ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
goto out;
}
rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
if (rc || getstatus) {
ctrl_info(ctrl, "Latch open on slot(%s)\n", slot_name(p_slot));
goto out;
}
rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
if (rc || getstatus) {
ctrl_info(ctrl, "Already enabled on slot(%s)\n",
slot_name(p_slot));
goto out;
}
p_slot->is_a_board = 1;
/* We have to save the presence info for these slots */
p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
p_slot->hpc_ops->get_power_status(p_slot, &(p_slot->pwr_save));
ctrl_dbg(ctrl, "%s: p_slot->pwr_save %x\n", __func__, p_slot->pwr_save);
p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
if ((p_slot->ctrl->pci_dev->vendor == PCI_VENDOR_ID_AMD &&
p_slot->ctrl->pci_dev->device == PCI_DEVICE_ID_AMD_POGO_7458)
&& p_slot->ctrl->num_slots == 1) {
/* handle AMD POGO errata; this must be done before enable */
amd_pogo_errata_save_misc_reg(p_slot);
retval = board_added(p_slot);
/* handle AMD POGO errata; this must be done after enable */
amd_pogo_errata_restore_misc_reg(p_slot);
} else
retval = board_added(p_slot);
if (retval) {
p_slot->hpc_ops->get_adapter_status(p_slot,
&(p_slot->presence_save));
p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
}
update_slot_info(p_slot);
out:
mutex_unlock(&p_slot->ctrl->crit_sect);
return retval;
}
static int shpchp_disable_slot (struct slot *p_slot)
{
u8 getstatus = 0;
int rc, retval = -ENODEV;
struct controller *ctrl = p_slot->ctrl;
if (!p_slot->ctrl)
return -ENODEV;
/* Check to see if (latch closed, card present, power on) */
mutex_lock(&p_slot->ctrl->crit_sect);
rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
if (rc || !getstatus) {
ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
goto out;
}
rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
if (rc || getstatus) {
ctrl_info(ctrl, "Latch open on slot(%s)\n", slot_name(p_slot));
goto out;
}
rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
if (rc || !getstatus) {
ctrl_info(ctrl, "Already disabled on slot(%s)\n",
slot_name(p_slot));
goto out;
}
retval = remove_board(p_slot);
update_slot_info(p_slot);
out:
mutex_unlock(&p_slot->ctrl->crit_sect);
return retval;
}
int shpchp_sysfs_enable_slot(struct slot *p_slot)
{
int retval = -ENODEV;
struct controller *ctrl = p_slot->ctrl;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case BLINKINGON_STATE:
cancel_delayed_work(&p_slot->work);
/* fall through */
case STATIC_STATE:
p_slot->state = POWERON_STATE;
mutex_unlock(&p_slot->lock);
retval = shpchp_enable_slot(p_slot);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
break;
case POWERON_STATE:
ctrl_info(ctrl, "Slot %s is already in powering on state\n",
slot_name(p_slot));
break;
case BLINKINGOFF_STATE:
case POWEROFF_STATE:
ctrl_info(ctrl, "Already enabled on slot %s\n",
slot_name(p_slot));
break;
default:
ctrl_err(ctrl, "Not a valid state on slot %s\n",
slot_name(p_slot));
break;
}
mutex_unlock(&p_slot->lock);
return retval;
}
int shpchp_sysfs_disable_slot(struct slot *p_slot)
{
int retval = -ENODEV;
struct controller *ctrl = p_slot->ctrl;
mutex_lock(&p_slot->lock);
switch (p_slot->state) {
case BLINKINGOFF_STATE:
cancel_delayed_work(&p_slot->work);
/* fall through */
case STATIC_STATE:
p_slot->state = POWEROFF_STATE;
mutex_unlock(&p_slot->lock);
retval = shpchp_disable_slot(p_slot);
mutex_lock(&p_slot->lock);
p_slot->state = STATIC_STATE;
break;
case POWEROFF_STATE:
ctrl_info(ctrl, "Slot %s is already in powering off state\n",
slot_name(p_slot));
break;
case BLINKINGON_STATE:
case POWERON_STATE:
ctrl_info(ctrl, "Already disabled on slot %s\n",
slot_name(p_slot));
break;
default:
ctrl_err(ctrl, "Not a valid state on slot %s\n",
slot_name(p_slot));
break;
}
mutex_unlock(&p_slot->lock);
return retval;
}
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