ALSA: line6: pod: Rewrite complex timer & work combo with a delayed work

The POD driver had a complex staged startup procedure using both timer
and work.  This patch simplifies it via a single delayed work with the
reduced stages.

Now basically only two intermediate stages:
- POD_STARTUP_VERSIONREQ:
  requesting the version information and the process_message callback
  triggers the next stage,
- POD_STARTUP_SETUP:
  registering the actual card object.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/line6/pod.c b/sound/usb/line6/pod.c
index ce45b6dab651718b6da3ee24f169063d2cadae85..995e6ccc81229a9167f5881cc048150d7a873d26 100644 (file)
--- a/sound/usb/line6/pod.c
+++ b/sound/usb/line6/pod.c
@@ -39,11 +39,9 @@
        Stages of POD startup procedure
 */
 enum {
-       POD_STARTUP_INIT = 1,
        POD_STARTUP_VERSIONREQ,
-       POD_STARTUP_WORKQUEUE,
        POD_STARTUP_SETUP,
-       POD_STARTUP_LAST = POD_STARTUP_SETUP - 1
+       POD_STARTUP_DONE,
 };
 
 enum {
@@ -63,12 +61,6 @@ struct usb_line6_pod {
        /* Instrument monitor level */
        int monitor_level;
 
-       /* Timer for device initialization */
-       struct timer_list startup_timer;
-
-       /* Work handler for device initialization */
-       struct work_struct startup_work;
-
        /* Current progress in startup procedure */
        int startup_progress;
 
@@ -173,10 +165,6 @@ static const char pod_version_header[] = {
        0xf2, 0x7e, 0x7f, 0x06, 0x02
 };
 
-/* forward declarations: */
-static void pod_startup2(struct timer_list *t);
-static void pod_startup3(struct usb_line6_pod *pod);
-
 static char *pod_alloc_sysex_buffer(struct usb_line6_pod *pod, int code,
                                    int size)
 {
@@ -196,7 +184,10 @@ static void line6_pod_process_message(struct usb_line6 *line6)
                pod->firmware_version = buf[13] * 100 + buf[14] * 10 + buf[15];
                pod->device_id = ((int)buf[8] << 16) | ((int)buf[9] << 8) |
                                 (int) buf[10];
-               pod_startup3(pod);
+               if (pod->startup_progress == POD_STARTUP_VERSIONREQ) {
+                       pod->startup_progress = POD_STARTUP_SETUP;
+                       schedule_delayed_work(&line6->startup_work, 0);
+               }
                return;
        }
 
@@ -281,47 +272,27 @@ static ssize_t device_id_show(struct device *dev,
        context). After the last one has finished, the device is ready to use.
 */
 
-static void pod_startup1(struct usb_line6_pod *pod)
-{
-       CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_INIT);
-
-       /* delay startup procedure: */
-       line6_start_timer(&pod->startup_timer, POD_STARTUP_DELAY, pod_startup2);
-}
-
-static void pod_startup2(struct timer_list *t)
+static void pod_startup(struct usb_line6 *line6)
 {
-       struct usb_line6_pod *pod = from_timer(pod, t, startup_timer);
-       struct usb_line6 *line6 = &pod->line6;
-
-       CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_VERSIONREQ);
-
-       /* request firmware version: */
-       line6_version_request_async(line6);
-}
-
-static void pod_startup3(struct usb_line6_pod *pod)
-{
-       CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_WORKQUEUE);
-
-       /* schedule work for global work queue: */
-       schedule_work(&pod->startup_work);
-}
-
-static void pod_startup4(struct work_struct *work)
-{
-       struct usb_line6_pod *pod =
-           container_of(work, struct usb_line6_pod, startup_work);
-       struct usb_line6 *line6 = &pod->line6;
-
-       CHECK_STARTUP_PROGRESS(pod->startup_progress, POD_STARTUP_SETUP);
-
-       /* serial number: */
-       line6_read_serial_number(&pod->line6, &pod->serial_number);
+       struct usb_line6_pod *pod = (struct usb_line6_pod *) line6;
 
-       /* ALSA audio interface: */
-       if (snd_card_register(line6->card))
-               dev_err(line6->ifcdev, "Failed to register POD card.\n");
+       switch (pod->startup_progress) {
+       case POD_STARTUP_VERSIONREQ:
+               /* request firmware version: */
+               line6_version_request_async(line6);
+               break;
+       case POD_STARTUP_SETUP:
+               /* serial number: */
+               line6_read_serial_number(&pod->line6, &pod->serial_number);
+
+               /* ALSA audio interface: */
+               if (snd_card_register(line6->card))
+                       dev_err(line6->ifcdev, "Failed to register POD card.\n");
+               pod->startup_progress = POD_STARTUP_DONE;
+               break;
+       default:
+               break;
+       }
 }
 
 /* POD special files: */
@@ -390,17 +361,6 @@ static const struct snd_kcontrol_new pod_control_monitor = {
        .put = snd_pod_control_monitor_put
 };
 
-/*
-       POD device disconnected.
-*/
-static void line6_pod_disconnect(struct usb_line6 *line6)
-{
-       struct usb_line6_pod *pod = (struct usb_line6_pod *)line6;
-
-       del_timer_sync(&pod->startup_timer);
-       cancel_work_sync(&pod->startup_work);
-}
-
 /*
         Try to init POD device.
 */
@@ -411,10 +371,7 @@ static int pod_init(struct usb_line6 *line6,
        struct usb_line6_pod *pod = (struct usb_line6_pod *) line6;
 
        line6->process_message = line6_pod_process_message;
-       line6->disconnect = line6_pod_disconnect;
-
-       timer_setup(&pod->startup_timer, NULL, 0);
-       INIT_WORK(&pod->startup_work, pod_startup4);
+       line6->startup = pod_startup;
 
        /* create sysfs entries: */
        err = snd_card_add_dev_attr(line6->card, &pod_dev_attr_group);
@@ -447,7 +404,8 @@ static int pod_init(struct usb_line6 *line6,
                pod->monitor_level = POD_SYSTEM_INVALID;
 
                /* initiate startup procedure: */
-               pod_startup1(pod);
+               schedule_delayed_work(&line6->startup_work,
+                                     msecs_to_jiffies(POD_STARTUP_DELAY));
        }
 
        return 0;