PCI: pciehp: Unify controller and slot structs

pciehp was originally introduced together with shpchp in a single
commit, c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI Express hot-plug
drivers"):
https://git.kernel.org/tglx/history/c/c16b4b14d980

shpchp supports up to 31 slots per controller, hence uses separate slot
and controller structs.  pciehp has a 1:1 relationship between slot and
controller and therefore never required this separation.  Nevertheless,
because much of the code had been copy-pasted between the two drivers,
pciehp likewise uses separate structs to this very day.

The artificial separation of data structures adds unnecessary complexity
and bloat to pciehp and requires constantly chasing pointers at runtime.

Simplify the driver by merging struct slot into struct controller.
Merge the slot constructor pcie_init_slot() and the destructor
pcie_cleanup_slot() into the controller counterparts.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 35 insertions, 79 deletions

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index d6cd4fbc72da..fa3759c4ab02 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -40,7 +40,7 @@ static inline int pciehp_request_irq(struct controller *ctrl)
 	if (pciehp_poll_mode) {
 		ctrl->poll_thread = kthread_run(&pciehp_poll, ctrl,
 						"pciehp_poll-%s",
-						slot_name(ctrl->slot));
+						slot_name(ctrl));
 		return PTR_ERR_OR_ZERO(ctrl->poll_thread);
 	}
 
@@ -315,8 +315,8 @@ static int pciehp_link_enable(struct controller *ctrl)
 int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 				    u8 *status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct controller *ctrl = hotplug_slot->private;
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
 
 	pci_config_pm_runtime_get(pdev);
@@ -328,8 +328,7 @@ int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 
 int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct controller *ctrl = slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
 
@@ -357,9 +356,8 @@ int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
 	return 0;
 }
 
-void pciehp_get_power_status(struct slot *slot, u8 *status)
+void pciehp_get_power_status(struct controller *ctrl, u8 *status)
 {
-	struct controller *ctrl = slot->ctrl;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
 
@@ -380,9 +378,9 @@ void pciehp_get_power_status(struct slot *slot, u8 *status)
 	}
 }
 
-void pciehp_get_latch_status(struct slot *slot, u8 *status)
+void pciehp_get_latch_status(struct controller *ctrl, u8 *status)
 {
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 
 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
@@ -412,9 +410,9 @@ bool pciehp_card_present_or_link_active(struct controller *ctrl)
 	return pciehp_card_present(ctrl) || pciehp_check_link_active(ctrl);
 }
 
-int pciehp_query_power_fault(struct slot *slot)
+int pciehp_query_power_fault(struct controller *ctrl)
 {
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 
 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
@@ -424,8 +422,7 @@ int pciehp_query_power_fault(struct slot *slot)
 int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 				    u8 status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct controller *ctrl = slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 
 	pci_config_pm_runtime_get(pdev);
@@ -435,9 +432,8 @@ int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 	return 0;
 }
 
-void pciehp_set_attention_status(struct slot *slot, u8 value)
+void pciehp_set_attention_status(struct controller *ctrl, u8 value)
 {
-	struct controller *ctrl = slot->ctrl;
 	u16 slot_cmd;
 
 	if (!ATTN_LED(ctrl))
@@ -461,10 +457,8 @@ void pciehp_set_attention_status(struct slot *slot, u8 value)
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
 }
 
-void pciehp_green_led_on(struct slot *slot)
+void pciehp_green_led_on(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	if (!PWR_LED(ctrl))
 		return;
 
@@ -475,10 +469,8 @@ void pciehp_green_led_on(struct slot *slot)
 		 PCI_EXP_SLTCTL_PWR_IND_ON);
 }
 
-void pciehp_green_led_off(struct slot *slot)
+void pciehp_green_led_off(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	if (!PWR_LED(ctrl))
 		return;
 
@@ -489,10 +481,8 @@ void pciehp_green_led_off(struct slot *slot)
 		 PCI_EXP_SLTCTL_PWR_IND_OFF);
 }
 
-void pciehp_green_led_blink(struct slot *slot)
+void pciehp_green_led_blink(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	if (!PWR_LED(ctrl))
 		return;
 
@@ -503,9 +493,8 @@ void pciehp_green_led_blink(struct slot *slot)
 		 PCI_EXP_SLTCTL_PWR_IND_BLINK);
 }
 
-int pciehp_power_on_slot(struct slot *slot)
+int pciehp_power_on_slot(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 	int retval;
@@ -529,10 +518,8 @@ int pciehp_power_on_slot(struct slot *slot)
 	return retval;
 }
 
-void pciehp_power_off_slot(struct slot *slot)
+void pciehp_power_off_slot(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
@@ -630,7 +617,6 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id)
 {
 	struct controller *ctrl = (struct controller *)dev_id;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
-	struct slot *slot = ctrl->slot;
 	irqreturn_t ret;
 	u32 events;
 
@@ -656,16 +642,16 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id)
 	/* Check Attention Button Pressed */
 	if (events & PCI_EXP_SLTSTA_ABP) {
 		ctrl_info(ctrl, "Slot(%s): Attention button pressed\n",
-			  slot_name(slot));
-		pciehp_handle_button_press(slot);
+			  slot_name(ctrl));
+		pciehp_handle_button_press(ctrl);
 	}
 
 	/* Check Power Fault Detected */
 	if ((events & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
 		ctrl->power_fault_detected = 1;
-		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(slot));
-		pciehp_set_attention_status(slot, 1);
-		pciehp_green_led_off(slot);
+		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
+		pciehp_set_attention_status(ctrl, 1);
+		pciehp_green_led_off(ctrl);
 	}
 
 	/*
@@ -674,9 +660,9 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id)
 	 */
 	down_read(&ctrl->reset_lock);
 	if (events & DISABLE_SLOT)
-		pciehp_handle_disable_request(slot);
+		pciehp_handle_disable_request(ctrl);
 	else if (events & (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC))
-		pciehp_handle_presence_or_link_change(slot, events);
+		pciehp_handle_presence_or_link_change(ctrl, events);
 	up_read(&ctrl->reset_lock);
 
 	pci_config_pm_runtime_put(pdev);
@@ -772,8 +758,7 @@ void pcie_clear_hotplug_events(struct controller *ctrl)
  */
 int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct controller *ctrl = slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 stat_mask = 0, ctrl_mask = 0;
 	int rc;
@@ -823,34 +808,6 @@ void pcie_shutdown_notification(struct controller *ctrl)
 	}
 }
 
-static int pcie_init_slot(struct controller *ctrl)
-{
-	struct pci_bus *subordinate = ctrl_dev(ctrl)->subordinate;
-	struct slot *slot;
-
-	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
-	if (!slot)
-		return -ENOMEM;
-
-	down_read(&pci_bus_sem);
-	slot->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE;
-	up_read(&pci_bus_sem);
-
-	slot->ctrl = ctrl;
-	mutex_init(&slot->lock);
-	INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
-	ctrl->slot = slot;
-	return 0;
-}
-
-static void pcie_cleanup_slot(struct controller *ctrl)
-{
-	struct slot *slot = ctrl->slot;
-
-	cancel_delayed_work_sync(&slot->work);
-	kfree(slot);
-}
-
 static inline void dbg_ctrl(struct controller *ctrl)
 {
 	struct pci_dev *pdev = ctrl->pcie->port;
@@ -874,10 +831,11 @@ struct controller *pcie_init(struct pcie_device *dev)
 	u32 slot_cap, link_cap;
 	u8 poweron;
 	struct pci_dev *pdev = dev->port;
+	struct pci_bus *subordinate = pdev->subordinate;
 
 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 	if (!ctrl)
-		goto abort;
+		return NULL;
 
 	ctrl->pcie = dev;
 	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
@@ -894,11 +852,17 @@ struct controller *pcie_init(struct pcie_device *dev)
 
 	ctrl->slot_cap = slot_cap;
 	mutex_init(&ctrl->ctrl_lock);
+	mutex_init(&ctrl->lock);
 	init_rwsem(&ctrl->reset_lock);
 	init_waitqueue_head(&ctrl->requester);
 	init_waitqueue_head(&ctrl->queue);
+	INIT_DELAYED_WORK(&ctrl->work, pciehp_queue_pushbutton_work);
 	dbg_ctrl(ctrl);
 
+	down_read(&pci_bus_sem);
+	ctrl->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE;
+	up_read(&pci_bus_sem);
+
 	/* Check if Data Link Layer Link Active Reporting is implemented */
 	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
 	if (link_cap & PCI_EXP_LNKCAP_DLLLARC)
@@ -924,32 +888,24 @@ struct controller *pcie_init(struct pcie_device *dev)
 		FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC),
 		pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : "");
 
-	if (pcie_init_slot(ctrl))
-		goto abort_ctrl;
-
 	/*
 	 * If empty slot's power status is on, turn power off.  The IRQ isn't
 	 * requested yet, so avoid triggering a notification with this command.
 	 */
 	if (POWER_CTRL(ctrl)) {
-		pciehp_get_power_status(ctrl->slot, &poweron);
+		pciehp_get_power_status(ctrl, &poweron);
 		if (!pciehp_card_present_or_link_active(ctrl) && poweron) {
 			pcie_disable_notification(ctrl);
-			pciehp_power_off_slot(ctrl->slot);
+			pciehp_power_off_slot(ctrl);
 		}
 	}
 
 	return ctrl;
-
-abort_ctrl:
-	kfree(ctrl);
-abort:
-	return NULL;
 }
 
 void pciehp_release_ctrl(struct controller *ctrl)
 {
-	pcie_cleanup_slot(ctrl);
+	cancel_delayed_work_sync(&ctrl->work);
 	kfree(ctrl);
 }