基于设备树的TQ2440的中断（2）

下面以按键中断为例看看基于设备数的中断的用法：

设备树：

    tq2440_key {
        compatible = "tq2440,key";
        interrupt-parent = <&gpf>;
        interrupts = < IRQ_TYPE_EDGE_FALLING>, < IRQ_TYPE_EDGE_FALLING>;
        key_3 = <&gpf  GPIO_ACTIVE_HIGH>;
        key_4 = <&gpf  GPIO_ACTIVE_HIGH>;
        key_8 = <&gpg  GPIO_ACTIVE_HIGH>;
    };

驱动：

 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
 #include <linux/of.h>
 #include <linux/of_gpio.h>
 #include <linux/interrupt.h>
 
 static irqreturn_t tq2440_key_isr(int irq, void *dev_id)
 {
     printk("%s enter, irq: %d, %s\n", __func__, irq, (char *)dev_id);
     return IRQ_HANDLED;
 }
 
 static int tq2440_key_probe(struct platform_device *pdev) {
     struct device *dev = &pdev->dev;
     int irq_gpio = -;
     int irq = -;
 
     printk("%s enter.\n", __func__);
 
     if (!dev->of_node) {
         dev_err(dev, "no platform data.\n");
         return -EINVAL;
     }
 
     irq = platform_get_irq(pdev, );
     printk("%s: get irq %d\n", __func__, irq);
     devm_request_any_context_irq(dev, irq,
         tq2440_key_isr, IRQF_TRIGGER_FALLING, "key-1", "key-1");
 
     irq = platform_get_irq(pdev, );
     printk("%s: get irq %d\n", __func__, irq);
     devm_request_any_context_irq(dev, irq,
         tq2440_key_isr, IRQF_TRIGGER_FALLING, "key-2", "key-2");
 
     irq_gpio = of_get_named_gpio(dev->of_node, "key_3", );
     irq = gpio_to_irq(irq_gpio);
     printk("%s: gpio: %d ---> irq (%d)\n", __func__, irq_gpio, irq);
     devm_request_any_context_irq(dev, irq,
         tq2440_key_isr, IRQF_TRIGGER_FALLING, "key-3", "key-3");
 
     irq_gpio = of_get_named_gpio(dev->of_node, "key_4", );
     irq = gpio_to_irq(irq_gpio);
     printk("%s: gpio: %d ---> irq (%d)\n", __func__, irq_gpio, irq);
     devm_request_any_context_irq(dev, irq,
         tq2440_key_isr, IRQF_TRIGGER_FALLING, "key-4", "key-4");
 
     irq_gpio = of_get_named_gpio(dev->of_node, "key_8", );
     irq = gpio_to_irq(irq_gpio);
     printk("%s: gpio: %d ---> irq (%d)\n", __func__, irq_gpio, irq);
     devm_request_any_context_irq(dev, irq,
         tq2440_key_isr, IRQF_TRIGGER_FALLING, "key-8", "key-8");
 
     return ;
 }
 
 static int tq2440_key_remove(struct platform_device *pdev) {
 
     printk("%s enter.\n", __func__);
 
     return ;
 }
 
 static const struct of_device_id tq2440_key_dt_ids[] = {
     { .compatible = "tq2440,key", },
     {},
 };
 
 MODULE_DEVICE_TABLE(of, tq2440_key_dt_ids);
 
 static struct platform_driver tq2440_key_driver = {
     .driver        = {
         .name    = "tq2440_key",
         .of_match_table    = of_match_ptr(tq2440_key_dt_ids),
     },
     .probe        = tq2440_key_probe,
     .remove        = tq2440_key_remove,
 };
 
 static int __init tq2440_key_init(void)
 {
     int ret;
 
     ret = platform_driver_register(&tq2440_key_driver);
     if (ret)
         printk(KERN_ERR "tq2440_key: probe failed: %d\n", ret);
 
     return ret;
 }
 module_init(tq2440_key_init);
 
 static void __exit tq2440_key_exit(void)
 {
     platform_driver_unregister(&tq2440_key_driver);
 }
 module_exit(tq2440_key_exit);
 
 MODULE_LICENSE("GPL");

启动后，加载驱动，可以看看/proc/interrupts：

[root@tq2440 mnt]# cat /proc/interrupts
           CPU0
  :          s3c-eint    Edge      eth0
  :                 s3c    Edge      s3c2410-rtc tick
 :             s3c   Edge      samsung_time_irq
 15:            s3c2410-eint0_3    Edge      key-
 :           s3c2410-eint0_3    Edge      key-
 :           s3c2410-eint0_3    Edge      key-
 :            s3c-eint    Edge      key-
 :            s3c-eint    Edge      key-
 :                 s3c   Edge      ohci_hcd:usb1
 :                 s3c   Edge      .i2c
 :                 s3c   Edge      s3c2410-rtc alarm
 :          s3c-level   Level     .serial
 :         s3c-level   Level     .serial
 :            s3c-level   Edge      .watchdog

下面是加载驱动的时候时的log：

<7>[   29.155953] tq2440_key_probe enter.
<7>[   29.156100] tq2440_key_probe: get irq 15
<7>[   29.156350] tq2440_key_probe: get irq 17
<7>[   29.156546] tq2440_key_probe: gpio: 86 ---> irq (18)
<7>[   29.156803] tq2440_key_probe: gpio: 88 ---> irq (19)
<7>[   29.157061] tq2440_key_probe: gpio: 92 ---> irq (20)

按键的时候会看到下面的log：

<7>[  350.161506] tq2440_key_isr enter, irq: 17, key-2
<7>[  354.624168] tq2440_key_isr enter, irq: 18, key-3
<7>[  355.301634] tq2440_key_isr enter, irq: 19, key-4
<7>[  357.053889] tq2440_key_isr enter, irq: 15, key-1
<7>[  368.231196] tq2440_key_isr enter, irq: 20, key-8

可以在中断处理函数中将调用栈打印出来：

EINT0_3中断对应的log：

<7>[  483.595441] [<bf008044>] (tq2440_key_isr [interrupts_demo]) from [<c00447d8>] (__handle_irq_event_percpu+0x3c/0x130)
<7>[  483.595481] [<c00447d8>] (__handle_irq_event_percpu) from [<c00448e8>] (handle_irq_event_percpu+0x1c/0x54)
<7>[  483.595521] [<c00448e8>] (handle_irq_event_percpu) from [<c0044948>] (handle_irq_event+0x28/0x3c)
<7>[  483.595558] [<c0044948>] (handle_irq_event) from [<c00476a8>] (handle_edge_irq+0xbc/0x190)
<7>[  483.595586] [<c00476a8>] (handle_edge_irq) from [<c0043fd8>] (generic_handle_irq+0x2c/0x40)
<7>[  483.595621] [<c0043fd8>] (generic_handle_irq) from [<c00441ac>] (__handle_domain_irq+0x6c/0xcc)
<7>[  483.595653] [<c00441ac>] (__handle_domain_irq) from [<c0009444>] (s3c24xx_handle_irq+0x6c/0x12c)
<7>[  483.595681] [<c0009444>] (s3c24xx_handle_irq) from [<c000e5fc>] (__irq_svc+0x5c/0x78)

EINT4：

<7>[  594.735684] [<bf008044>] (tq2440_key_isr [interrupts_demo]) from [<c00447d8>] (__handle_irq_event_percpu+0x3c/0x130)
<7>[  594.735725] [<c00447d8>] (__handle_irq_event_percpu) from [<c00448e8>] (handle_irq_event_percpu+0x1c/0x54)
<7>[  594.735764] [<c00448e8>] (handle_irq_event_percpu) from [<c0044948>] (handle_irq_event+0x28/0x3c)
<7>[  594.735801] [<c0044948>] (handle_irq_event) from [<c00476a8>] (handle_edge_irq+0xbc/0x190)
<7>[  594.735832] [<c00476a8>] (handle_edge_irq) from [<c0043fd8>] (generic_handle_irq+0x2c/0x40)
<7>[  594.735878] [<c0043fd8>] (generic_handle_irq) from [<c02490f4>] (s3c24xx_demux_eint4_7+0xa4/0x120)
<7>[  594.735916] [<c02490f4>] (s3c24xx_demux_eint4_7) from [<c00441ac>] (__handle_domain_irq+0x6c/0xcc)
<7>[  594.735946] [<c00441ac>] (__handle_domain_irq) from [<c0009444>] (s3c24xx_handle_irq+0x6c/0x12c)
<7>[  594.735975] [<c0009444>] (s3c24xx_handle_irq) from [<c000e5fc>] (__irq_svc+0x5c/0x78)

EINT8：

<7>[  652.506024] [<bf008044>] (tq2440_key_isr [interrupts_demo]) from [<c00447d8>] (__handle_irq_event_percpu+0x3c/0x130)
<7>[  652.506065] [<c00447d8>] (__handle_irq_event_percpu) from [<c00448e8>] (handle_irq_event_percpu+0x1c/0x54)
<7>[  652.506106] [<c00448e8>] (handle_irq_event_percpu) from [<c0044948>] (handle_irq_event+0x28/0x3c)
<7>[  652.506142] [<c0044948>] (handle_irq_event) from [<c00476a8>] (handle_edge_irq+0xbc/0x190)
<7>[  652.506171] [<c00476a8>] (handle_edge_irq) from [<c0043fd8>] (generic_handle_irq+0x2c/0x40)
<7>[  652.506219] [<c0043fd8>] (generic_handle_irq) from [<c0249224>] (s3c24xx_demux_eint8_23+0xb4/0x130)
<7>[  652.506258] [<c0249224>] (s3c24xx_demux_eint8_23) from [<c00441ac>] (__handle_domain_irq+0x6c/0xcc)
<7>[  652.506287] [<c00441ac>] (__handle_domain_irq) from [<c0009444>] (s3c24xx_handle_irq+0x6c/0x12c)
<7>[  652.506316] [<c0009444>] (s3c24xx_handle_irq) from [<c000e5fc>] (__irq_svc+0x5c/0x78)

完。