| // 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/kernel.h> |
| #include <linux/types.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/pci.h> |
| #include "pciehp.h" |
| |
| /* The following routines constitute the bulk of the |
| hotplug controller logic |
| */ |
| |
| #define SAFE_REMOVAL true |
| #define SURPRISE_REMOVAL false |
| |
| static void set_slot_off(struct controller *ctrl) |
| { |
| /* turn off slot, turn on Amber LED, turn off Green LED if supported*/ |
| if (POWER_CTRL(ctrl)) { |
| pciehp_power_off_slot(ctrl); |
| |
| /* |
| * 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(ctrl); |
| pciehp_set_attention_status(ctrl, 1); |
| } |
| |
| /** |
| * board_added - Called after a board has been added to the system. |
| * @ctrl: PCIe hotplug controller where board is added |
| * |
| * Turns power on for the board. |
| * Configures board. |
| */ |
| static int board_added(struct controller *ctrl) |
| { |
| int retval = 0; |
| struct pci_bus *parent = ctrl->pcie->port->subordinate; |
| |
| if (POWER_CTRL(ctrl)) { |
| /* Power on slot */ |
| retval = pciehp_power_on_slot(ctrl); |
| if (retval) |
| return retval; |
| } |
| |
| pciehp_green_led_blink(ctrl); |
| |
| /* 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(ctrl)) { |
| ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl)); |
| retval = -EIO; |
| goto err_exit; |
| } |
| |
| retval = pciehp_configure_device(ctrl); |
| 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(ctrl); |
| pciehp_set_attention_status(ctrl, 0); |
| return 0; |
| |
| err_exit: |
| set_slot_off(ctrl); |
| return retval; |
| } |
| |
| /** |
| * remove_board - Turns off slot and LEDs |
| * @ctrl: PCIe hotplug controller where board is being removed |
| * @safe_removal: whether the board is safely removed (versus surprise removed) |
| */ |
| static void remove_board(struct controller *ctrl, bool safe_removal) |
| { |
| pciehp_unconfigure_device(ctrl, safe_removal); |
| |
| if (POWER_CTRL(ctrl)) { |
| pciehp_power_off_slot(ctrl); |
| |
| /* |
| * 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); |
| |
| /* Ignore link or presence changes caused by power off */ |
| atomic_and(~(PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC), |
| &ctrl->pending_events); |
| } |
| |
| /* turn off Green LED */ |
| pciehp_green_led_off(ctrl); |
| } |
| |
| static int pciehp_enable_slot(struct controller *ctrl); |
| static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal); |
| |
| 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 controller *ctrl = container_of(work, struct controller, |
| button_work.work); |
| |
| mutex_lock(&ctrl->state_lock); |
| switch (ctrl->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(&ctrl->state_lock); |
| } |
| |
| void pciehp_handle_button_press(struct controller *ctrl) |
| { |
| mutex_lock(&ctrl->state_lock); |
| switch (ctrl->state) { |
| case OFF_STATE: |
| case ON_STATE: |
| if (ctrl->state == ON_STATE) { |
| ctrl->state = BLINKINGOFF_STATE; |
| ctrl_info(ctrl, "Slot(%s): Powering off due to button press\n", |
| slot_name(ctrl)); |
| } else { |
| ctrl->state = BLINKINGON_STATE; |
| ctrl_info(ctrl, "Slot(%s) Powering on due to button press\n", |
| slot_name(ctrl)); |
| } |
| /* blink green LED and turn off amber */ |
| pciehp_green_led_blink(ctrl); |
| pciehp_set_attention_status(ctrl, 0); |
| schedule_delayed_work(&ctrl->button_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(ctrl)); |
| cancel_delayed_work(&ctrl->button_work); |
| if (ctrl->state == BLINKINGOFF_STATE) { |
| ctrl->state = ON_STATE; |
| pciehp_green_led_on(ctrl); |
| } else { |
| ctrl->state = OFF_STATE; |
| pciehp_green_led_off(ctrl); |
| } |
| pciehp_set_attention_status(ctrl, 0); |
| ctrl_info(ctrl, "Slot(%s): Action canceled due to button press\n", |
| slot_name(ctrl)); |
| break; |
| default: |
| ctrl_err(ctrl, "Slot(%s): Ignoring invalid state %#x\n", |
| slot_name(ctrl), ctrl->state); |
| break; |
| } |
| mutex_unlock(&ctrl->state_lock); |
| } |
| |
| void pciehp_handle_disable_request(struct controller *ctrl) |
| { |
| mutex_lock(&ctrl->state_lock); |
| switch (ctrl->state) { |
| case BLINKINGON_STATE: |
| case BLINKINGOFF_STATE: |
| cancel_delayed_work(&ctrl->button_work); |
| break; |
| } |
| ctrl->state = POWEROFF_STATE; |
| mutex_unlock(&ctrl->state_lock); |
| |
| ctrl->request_result = pciehp_disable_slot(ctrl, SAFE_REMOVAL); |
| } |
| |
| void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events) |
| { |
| bool present, link_active; |
| |
| /* |
| * 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(&ctrl->state_lock); |
| switch (ctrl->state) { |
| case BLINKINGOFF_STATE: |
| cancel_delayed_work(&ctrl->button_work); |
| /* fall through */ |
| case ON_STATE: |
| ctrl->state = POWEROFF_STATE; |
| mutex_unlock(&ctrl->state_lock); |
| if (events & PCI_EXP_SLTSTA_DLLSC) |
| ctrl_info(ctrl, "Slot(%s): Link Down\n", |
| slot_name(ctrl)); |
| if (events & PCI_EXP_SLTSTA_PDC) |
| ctrl_info(ctrl, "Slot(%s): Card not present\n", |
| slot_name(ctrl)); |
| pciehp_disable_slot(ctrl, SURPRISE_REMOVAL); |
| break; |
| default: |
| mutex_unlock(&ctrl->state_lock); |
| break; |
| } |
| |
| /* Turn the slot on if it's occupied or link is up */ |
| mutex_lock(&ctrl->state_lock); |
| present = pciehp_card_present(ctrl); |
| link_active = pciehp_check_link_active(ctrl); |
| if (!present && !link_active) { |
| mutex_unlock(&ctrl->state_lock); |
| return; |
| } |
| |
| switch (ctrl->state) { |
| case BLINKINGON_STATE: |
| cancel_delayed_work(&ctrl->button_work); |
| /* fall through */ |
| case OFF_STATE: |
| ctrl->state = POWERON_STATE; |
| mutex_unlock(&ctrl->state_lock); |
| if (present) |
| ctrl_info(ctrl, "Slot(%s): Card present\n", |
| slot_name(ctrl)); |
| if (link_active) |
| ctrl_info(ctrl, "Slot(%s): Link Up\n", |
| slot_name(ctrl)); |
| ctrl->request_result = pciehp_enable_slot(ctrl); |
| break; |
| default: |
| mutex_unlock(&ctrl->state_lock); |
| break; |
| } |
| } |
| |
| static int __pciehp_enable_slot(struct controller *ctrl) |
| { |
| u8 getstatus = 0; |
| |
| if (MRL_SENS(ctrl)) { |
| pciehp_get_latch_status(ctrl, &getstatus); |
| if (getstatus) { |
| ctrl_info(ctrl, "Slot(%s): Latch open\n", |
| slot_name(ctrl)); |
| return -ENODEV; |
| } |
| } |
| |
| if (POWER_CTRL(ctrl)) { |
| pciehp_get_power_status(ctrl, &getstatus); |
| if (getstatus) { |
| ctrl_info(ctrl, "Slot(%s): Already enabled\n", |
| slot_name(ctrl)); |
| return 0; |
| } |
| } |
| |
| return board_added(ctrl); |
| } |
| |
| static int pciehp_enable_slot(struct controller *ctrl) |
| { |
| int ret; |
| |
| pm_runtime_get_sync(&ctrl->pcie->port->dev); |
| ret = __pciehp_enable_slot(ctrl); |
| if (ret && ATTN_BUTTN(ctrl)) |
| pciehp_green_led_off(ctrl); /* may be blinking */ |
| pm_runtime_put(&ctrl->pcie->port->dev); |
| |
| mutex_lock(&ctrl->state_lock); |
| ctrl->state = ret ? OFF_STATE : ON_STATE; |
| mutex_unlock(&ctrl->state_lock); |
| |
| return ret; |
| } |
| |
| static int __pciehp_disable_slot(struct controller *ctrl, bool safe_removal) |
| { |
| u8 getstatus = 0; |
| |
| if (POWER_CTRL(ctrl)) { |
| pciehp_get_power_status(ctrl, &getstatus); |
| if (!getstatus) { |
| ctrl_info(ctrl, "Slot(%s): Already disabled\n", |
| slot_name(ctrl)); |
| return -EINVAL; |
| } |
| } |
| |
| remove_board(ctrl, safe_removal); |
| return 0; |
| } |
| |
| static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal) |
| { |
| int ret; |
| |
| pm_runtime_get_sync(&ctrl->pcie->port->dev); |
| ret = __pciehp_disable_slot(ctrl, safe_removal); |
| pm_runtime_put(&ctrl->pcie->port->dev); |
| |
| mutex_lock(&ctrl->state_lock); |
| ctrl->state = OFF_STATE; |
| mutex_unlock(&ctrl->state_lock); |
| |
| return ret; |
| } |
| |
| int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot) |
| { |
| struct controller *ctrl = to_ctrl(hotplug_slot); |
| |
| mutex_lock(&ctrl->state_lock); |
| switch (ctrl->state) { |
| case BLINKINGON_STATE: |
| case OFF_STATE: |
| mutex_unlock(&ctrl->state_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(ctrl)); |
| break; |
| case BLINKINGOFF_STATE: |
| case ON_STATE: |
| case POWEROFF_STATE: |
| ctrl_info(ctrl, "Slot(%s): Already enabled\n", |
| slot_name(ctrl)); |
| break; |
| default: |
| ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n", |
| slot_name(ctrl), ctrl->state); |
| break; |
| } |
| mutex_unlock(&ctrl->state_lock); |
| |
| return -ENODEV; |
| } |
| |
| int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot) |
| { |
| struct controller *ctrl = to_ctrl(hotplug_slot); |
| |
| mutex_lock(&ctrl->state_lock); |
| switch (ctrl->state) { |
| case BLINKINGOFF_STATE: |
| case ON_STATE: |
| mutex_unlock(&ctrl->state_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(ctrl)); |
| break; |
| case BLINKINGON_STATE: |
| case OFF_STATE: |
| case POWERON_STATE: |
| ctrl_info(ctrl, "Slot(%s): Already disabled\n", |
| slot_name(ctrl)); |
| break; |
| default: |
| ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n", |
| slot_name(ctrl), ctrl->state); |
| break; |
| } |
| mutex_unlock(&ctrl->state_lock); |
| |
| return -ENODEV; |
| } |