| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|
| 2 | /* |
|---|
| 3 | * Copyright IBM Corp. 2001,2008 |
|---|
| 4 | * |
|---|
| 5 | * This file contains the IRQ specific code for hvc_console |
|---|
| 6 | * |
|---|
| 7 | */ |
|---|
| 8 | |
|---|
| 9 | #include <linux/interrupt.h> |
|---|
| 10 | |
|---|
| 11 | #include "hvc_console.h" |
|---|
| 12 | |
|---|
| 13 | static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance) |
|---|
| 14 | { |
|---|
| 15 | /* if hvc_poll request a repoll, then kick the hvcd thread */ |
|---|
| 16 | if (hvc_poll(hp: dev_instance)) |
|---|
| 17 | hvc_kick(); |
|---|
| 18 | |
|---|
| 19 | /* |
|---|
| 20 | * We're safe to always return IRQ_HANDLED as the hvcd thread will |
|---|
| 21 | * iterate through each hvc_struct. |
|---|
| 22 | */ |
|---|
| 23 | return IRQ_HANDLED; |
|---|
| 24 | } |
|---|
| 25 | |
|---|
| 26 | /* |
|---|
| 27 | * For IRQ based systems these callbacks can be used |
|---|
| 28 | */ |
|---|
| 29 | int notifier_add_irq(struct hvc_struct *hp, int irq) |
|---|
| 30 | { |
|---|
| 31 | int rc; |
|---|
| 32 | |
|---|
| 33 | if (!irq) { |
|---|
| 34 | hp->irq_requested = 0; |
|---|
| 35 | return 0; |
|---|
| 36 | } |
|---|
| 37 | rc = request_irq(irq, handler: hvc_handle_interrupt, flags: hp->flags, |
|---|
| 38 | name: "hvc_console" , dev: hp); |
|---|
| 39 | if (!rc) |
|---|
| 40 | hp->irq_requested = 1; |
|---|
| 41 | return rc; |
|---|
| 42 | } |
|---|
| 43 | |
|---|
| 44 | void notifier_del_irq(struct hvc_struct *hp, int irq) |
|---|
| 45 | { |
|---|
| 46 | if (!hp->irq_requested) |
|---|
| 47 | return; |
|---|
| 48 | free_irq(irq, hp); |
|---|
| 49 | hp->irq_requested = 0; |
|---|
| 50 | } |
|---|
| 51 | |
|---|
| 52 | void notifier_hangup_irq(struct hvc_struct *hp, int irq) |
|---|
| 53 | { |
|---|
| 54 | notifier_del_irq(hp, irq); |
|---|
| 55 | } |
|---|
| 56 | |
|---|
