[PATCH v2 16/22] wifi: ath12k: convert tasklet to BH workqueue for CE interrupts

[Raj Kumar Bhagat <quic_rajkbhag@xxxxxxxxxxx>]

Currently in Ath12k, tasklet is used to handle the BH context of CE
interrupts. However the tasklet is marked deprecated and has some
design flaws. To replace tasklets, BH workqueue support has been
added. BH workqueue behaves similarly to regular workqueues except
that the queued work items are executed in the BH context.

Hence, convert the tasklet to BH workqueue for handling CE interrupts
in the BH context.

Tested-on: IPQ5332 hw1.0 AHB WLAN.WBE.1.3.1-00130-QCAHKSWPL_SILICONZ-1
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.1.1-00210-QCAHKSWPL_SILICONZ-1

Signed-off-by: Raj Kumar Bhagat <quic_rajkbhag@xxxxxxxxxxx>
---
 drivers/net/wireless/ath/ath12k/ce.h  |  2 +-
 drivers/net/wireless/ath/ath12k/pci.c | 14 +++++++-------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/ce.h b/drivers/net/wireless/ath/ath12k/ce.h
index 9dd71056e1c5..75c9f8f1f7c6 100644
--- a/drivers/net/wireless/ath/ath12k/ce.h
+++ b/drivers/net/wireless/ath/ath12k/ce.h
@@ -159,7 +159,7 @@ struct ath12k_ce_pipe {
 	void (*send_cb)(struct ath12k_ce_pipe *pipe);
 	void (*recv_cb)(struct ath12k_base *ab, struct sk_buff *skb);
 
-	struct tasklet_struct intr_tq;
+	struct work_struct intr_wq;
 	struct ath12k_ce_ring *src_ring;
 	struct ath12k_ce_ring *dest_ring;
 	struct ath12k_ce_ring *status_ring;
diff --git a/drivers/net/wireless/ath/ath12k/pci.c b/drivers/net/wireless/ath/ath12k/pci.c
index 0c393bc30f92..9a50d813e9b4 100644
--- a/drivers/net/wireless/ath/ath12k/pci.c
+++ b/drivers/net/wireless/ath/ath12k/pci.c
@@ -425,9 +425,9 @@ static void ath12k_pci_sync_ce_irqs(struct ath12k_base *ab)
 	}
 }
 
-static void ath12k_pci_ce_tasklet(struct tasklet_struct *t)
+static void ath12k_pci_ce_workqueue(struct work_struct *work)
 {
-	struct ath12k_ce_pipe *ce_pipe = from_tasklet(ce_pipe, t, intr_tq);
+	struct ath12k_ce_pipe *ce_pipe = from_work(ce_pipe, work, intr_wq);
 	int irq_idx = ATH12K_PCI_IRQ_CE0_OFFSET + ce_pipe->pipe_num;
 
 	ath12k_ce_per_engine_service(ce_pipe->ab, ce_pipe->pipe_num);
@@ -449,7 +449,7 @@ static irqreturn_t ath12k_pci_ce_interrupt_handler(int irq, void *arg)
 
 	disable_irq_nosync(ab->irq_num[irq_idx]);
 
-	tasklet_schedule(&ce_pipe->intr_tq);
+	queue_work(system_bh_wq, &ce_pipe->intr_wq);
 
 	return IRQ_HANDLED;
 }
@@ -675,7 +675,7 @@ static int ath12k_pci_config_irq(struct ath12k_base *ab)
 
 		irq_idx = ATH12K_PCI_IRQ_CE0_OFFSET + i;
 
-		tasklet_setup(&ce_pipe->intr_tq, ath12k_pci_ce_tasklet);
+		INIT_WORK(&ce_pipe->intr_wq, ath12k_pci_ce_workqueue);
 
 		ret = request_irq(irq, ath12k_pci_ce_interrupt_handler,
 				  ab_pci->irq_flags, irq_name[irq_idx],
@@ -962,7 +962,7 @@ static void ath12k_pci_aspm_restore(struct ath12k_pci *ab_pci)
 						   PCI_EXP_LNKCTL_ASPMC);
 }
 
-static void ath12k_pci_kill_tasklets(struct ath12k_base *ab)
+static void ath12k_pci_cancel_workqueue(struct ath12k_base *ab)
 {
 	int i;
 
@@ -972,7 +972,7 @@ static void ath12k_pci_kill_tasklets(struct ath12k_base *ab)
 		if (ath12k_ce_get_attr_flags(ab, i) & CE_ATTR_DIS_INTR)
 			continue;
 
-		tasklet_kill(&ce_pipe->intr_tq);
+		cancel_work_sync(&ce_pipe->intr_wq);
 	}
 }
 
@@ -980,7 +980,7 @@ static void ath12k_pci_ce_irq_disable_sync(struct ath12k_base *ab)
 {
 	ath12k_pci_ce_irqs_disable(ab);
 	ath12k_pci_sync_ce_irqs(ab);
-	ath12k_pci_kill_tasklets(ab);
+	ath12k_pci_cancel_workqueue(ab);
 }
 
 int ath12k_pci_map_service_to_pipe(struct ath12k_base *ab, u16 service_id,
-- 
2.34.1