[PATCH v2 0/5] ALSA: line6 fixes and cleanups

[PATCH v2 0/5] ALSA: line6 fixes and cleanups

[Takashi Iwai]

Hi,

this is a patchset I forgot to merge for fixing and impriving LINE6
drivers.  The v2 is rebased after the latest toneport fix, and
contains a cleanup with container_of(), too.


Takashi

===

Takashi Iwai (5):
  ALSA: line6: pod: Rewrite complex timer & work combo with a delayed
    work
  ALSA: line6: podhd: Rewrite complex timer & work combo with a delayed
    work
  ALSA: line6: variax: Rewrite complex timer & work combo with a delayed
    work
  ALSA: line6: Drop superfluous timer helper function
  ALSA: line6: Use container_of()

 sound/usb/line6/driver.c   |  11 ----
 sound/usb/line6/driver.h   |   9 ---
 sound/usb/line6/pod.c      | 108 +++++++++++------------------------
 sound/usb/line6/podhd.c    |  80 ++++----------------------
 sound/usb/line6/toneport.c |  14 ++---
 sound/usb/line6/variax.c   | 138 ++++++++++++++-------------------------------
 6 files changed, 94 insertions(+), 266 deletions(-)

-- 
2.16.4

[PATCH v2 1/5] ALSA: line6: pod: Rewrite complex timer & work combo with a delayed work

[Takashi Iwai]

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>
---
 sound/usb/line6/pod.c | 96 +++++++++++++++------------------------------------
 1 file changed, 27 insertions(+), 69 deletions(-)

diff --git a/sound/usb/line6/pod.c b/sound/usb/line6/pod.c
index ce45b6dab651..995e6ccc8122 100644
--- 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;
-- 
2.16.4

[PATCH v2 2/5] ALSA: line6: podhd: Rewrite complex timer & work combo with a delayed work

[Takashi Iwai]

POD HD driver had a complex staged startup sequence with both timer
and work.  This patch simplifies it to a single delayed work with a
single stage.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/usb/line6/podhd.c | 74 ++++++-------------------------------------------
 1 file changed, 8 insertions(+), 66 deletions(-)

diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c
index 5f3c87264e66..722fc5db09c5 100644
--- a/sound/usb/line6/podhd.c
+++ b/sound/usb/line6/podhd.c
@@ -22,16 +22,6 @@
 
 #define PODHD_STARTUP_DELAY 500
 
-/*
- * Stages of POD startup procedure
- */
-enum {
-	PODHD_STARTUP_INIT = 1,
-	PODHD_STARTUP_SCHEDULE_WORKQUEUE,
-	PODHD_STARTUP_SETUP,
-	PODHD_STARTUP_LAST = PODHD_STARTUP_SETUP - 1
-};
-
 enum {
 	LINE6_PODHD300,
 	LINE6_PODHD400,
@@ -47,15 +37,6 @@ struct usb_line6_podhd {
 	/* Generic Line 6 USB data */
 	struct usb_line6 line6;
 
-	/* 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;
-
 	/* Serial number of device */
 	u32 serial_number;
 
@@ -158,10 +139,6 @@ static struct line6_pcm_properties podx3_pcm_properties = {
 };
 static struct usb_driver podhd_driver;
 
-static void podhd_startup_start_workqueue(struct timer_list *t);
-static void podhd_startup_workqueue(struct work_struct *work);
-static int podhd_startup_finalize(struct usb_line6_podhd *pod);
-
 static ssize_t serial_number_show(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
@@ -202,26 +179,6 @@ static const struct attribute_group podhd_dev_attr_group = {
  * audio nor bulk interfaces to work.
  */
 
-static void podhd_startup(struct usb_line6_podhd *pod)
-{
-	CHECK_STARTUP_PROGRESS(pod->startup_progress, PODHD_STARTUP_INIT);
-
-	/* delay startup procedure: */
-	line6_start_timer(&pod->startup_timer, PODHD_STARTUP_DELAY,
-		podhd_startup_start_workqueue);
-}
-
-static void podhd_startup_start_workqueue(struct timer_list *t)
-{
-	struct usb_line6_podhd *pod = from_timer(pod, t, startup_timer);
-
-	CHECK_STARTUP_PROGRESS(pod->startup_progress,
-		PODHD_STARTUP_SCHEDULE_WORKQUEUE);
-
-	/* schedule work for global work queue: */
-	schedule_work(&pod->startup_work);
-}
-
 static int podhd_dev_start(struct usb_line6_podhd *pod)
 {
 	int ret;
@@ -272,25 +229,14 @@ static int podhd_dev_start(struct usb_line6_podhd *pod)
 	return ret;
 }
 
-static void podhd_startup_workqueue(struct work_struct *work)
+static void podhd_startup(struct usb_line6 *line6)
 {
-	struct usb_line6_podhd *pod =
-	    container_of(work, struct usb_line6_podhd, startup_work);
-
-	CHECK_STARTUP_PROGRESS(pod->startup_progress, PODHD_STARTUP_SETUP);
+	struct usb_line6_podhd *pod = (struct usb_line6_podhd *)line6;
 
 	podhd_dev_start(pod);
 	line6_read_serial_number(&pod->line6, &pod->serial_number);
-
-	podhd_startup_finalize(pod);
-}
-
-static int podhd_startup_finalize(struct usb_line6_podhd *pod)
-{
-	struct usb_line6 *line6 = &pod->line6;
-
-	/* ALSA audio interface: */
-	return snd_card_register(line6->card);
+	if (snd_card_register(line6->card))
+		dev_err(line6->ifcdev, "Failed to register POD HD card.\n");
 }
 
 static void podhd_disconnect(struct usb_line6 *line6)
@@ -300,9 +246,6 @@ static void podhd_disconnect(struct usb_line6 *line6)
 	if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL_INFO) {
 		struct usb_interface *intf;
 
-		del_timer_sync(&pod->startup_timer);
-		cancel_work_sync(&pod->startup_work);
-
 		intf = usb_ifnum_to_if(line6->usbdev,
 					pod->line6.properties->ctrl_if);
 		if (intf)
@@ -321,9 +264,7 @@ static int podhd_init(struct usb_line6 *line6,
 	struct usb_interface *intf;
 
 	line6->disconnect = podhd_disconnect;
-
-	timer_setup(&pod->startup_timer, NULL, 0);
-	INIT_WORK(&pod->startup_work, podhd_startup_workqueue);
+	line6->startup = podhd_startup;
 
 	if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL) {
 		/* claim the data interface */
@@ -362,11 +303,12 @@ static int podhd_init(struct usb_line6 *line6,
 
 	if (!(pod->line6.properties->capabilities & LINE6_CAP_CONTROL_INFO)) {
 		/* register USB audio system directly */
-		return podhd_startup_finalize(pod);
+		return snd_card_register(line6->card);
 	}
 
 	/* init device and delay registering */
-	podhd_startup(pod);
+	schedule_delayed_work(&line6->startup_work,
+			      msecs_to_jiffies(PODHD_STARTUP_DELAY));
 	return 0;
 }
 
-- 
2.16.4

[PATCH v2 3/5] ALSA: line6: variax: Rewrite complex timer & work combo with a delayed work

[Takashi Iwai]

Variax driver had a very complex and staged startup sequence using
multiple timers and a work.  This patch simplifies the procedure to a
single delayed work.

Now the startup stage consists of:
- VARIAX_STARTUP_VERSIONREQ:
  requesting the version and the message handler raises up to the next
  stage upon receiving the reply.  The request is repeated until a
  reply arrives.
- VARIAX_STARTUP_ACTIVATE:
  does activation, and queue for the next stage.
- VARIAX_STARTUP_SETUP:
  registers the card.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/usb/line6/variax.c | 128 +++++++++++++----------------------------------
 1 file changed, 35 insertions(+), 93 deletions(-)

diff --git a/sound/usb/line6/variax.c b/sound/usb/line6/variax.c
index e8c852b2ce35..fb114156b7ca 100644
--- a/sound/usb/line6/variax.c
+++ b/sound/usb/line6/variax.c
@@ -26,13 +26,9 @@
 	Stages of Variax startup procedure
 */
 enum {
-	VARIAX_STARTUP_INIT = 1,
 	VARIAX_STARTUP_VERSIONREQ,
-	VARIAX_STARTUP_WAIT,
 	VARIAX_STARTUP_ACTIVATE,
-	VARIAX_STARTUP_WORKQUEUE,
 	VARIAX_STARTUP_SETUP,
-	VARIAX_STARTUP_LAST = VARIAX_STARTUP_SETUP - 1
 };
 
 enum {
@@ -47,13 +43,6 @@ struct usb_line6_variax {
 	/* Buffer for activation code */
 	unsigned char *buffer_activate;
 
-	/* Handler for device initialization */
-	struct work_struct startup_work;
-
-	/* Timers for device initialization */
-	struct timer_list startup_timer1;
-	struct timer_list startup_timer2;
-
 	/* Current progress in startup procedure */
 	int startup_progress;
 };
@@ -81,11 +70,6 @@ static const char variax_activate[] = {
 	0xf7
 };
 
-/* forward declarations: */
-static void variax_startup2(struct timer_list *t);
-static void variax_startup4(struct timer_list *t);
-static void variax_startup5(struct timer_list *t);
-
 static void variax_activate_async(struct usb_line6_variax *variax, int a)
 {
 	variax->buffer_activate[VARIAX_OFFSET_ACTIVATE] = a;
@@ -100,74 +84,30 @@ static void variax_activate_async(struct usb_line6_variax *variax, int a)
 	context). After the last one has finished, the device is ready to use.
 */
 
-static void variax_startup1(struct usb_line6_variax *variax)
-{
-	CHECK_STARTUP_PROGRESS(variax->startup_progress, VARIAX_STARTUP_INIT);
-
-	/* delay startup procedure: */
-	line6_start_timer(&variax->startup_timer1, VARIAX_STARTUP_DELAY1,
-			  variax_startup2);
-}
-
-static void variax_startup2(struct timer_list *t)
-{
-	struct usb_line6_variax *variax = from_timer(variax, t, startup_timer1);
-	struct usb_line6 *line6 = &variax->line6;
-
-	/* schedule another startup procedure until startup is complete: */
-	if (variax->startup_progress >= VARIAX_STARTUP_LAST)
-		return;
-
-	variax->startup_progress = VARIAX_STARTUP_VERSIONREQ;
-	line6_start_timer(&variax->startup_timer1, VARIAX_STARTUP_DELAY1,
-			  variax_startup2);
-
-	/* request firmware version: */
-	line6_version_request_async(line6);
-}
-
-static void variax_startup3(struct usb_line6_variax *variax)
+static void variax_startup(struct usb_line6 *line6)
 {
-	CHECK_STARTUP_PROGRESS(variax->startup_progress, VARIAX_STARTUP_WAIT);
-
-	/* delay startup procedure: */
-	line6_start_timer(&variax->startup_timer2, VARIAX_STARTUP_DELAY3,
-			  variax_startup4);
-}
-
-static void variax_startup4(struct timer_list *t)
-{
-	struct usb_line6_variax *variax = from_timer(variax, t, startup_timer2);
-
-	CHECK_STARTUP_PROGRESS(variax->startup_progress,
-			       VARIAX_STARTUP_ACTIVATE);
-
-	/* activate device: */
-	variax_activate_async(variax, 1);
-	line6_start_timer(&variax->startup_timer2, VARIAX_STARTUP_DELAY4,
-			  variax_startup5);
-}
-
-static void variax_startup5(struct timer_list *t)
-{
-	struct usb_line6_variax *variax = from_timer(variax, t, startup_timer2);
-
-	CHECK_STARTUP_PROGRESS(variax->startup_progress,
-			       VARIAX_STARTUP_WORKQUEUE);
-
-	/* schedule work for global work queue: */
-	schedule_work(&variax->startup_work);
-}
-
-static void variax_startup6(struct work_struct *work)
-{
-	struct usb_line6_variax *variax =
-	    container_of(work, struct usb_line6_variax, startup_work);
-
-	CHECK_STARTUP_PROGRESS(variax->startup_progress, VARIAX_STARTUP_SETUP);
+	struct usb_line6_variax *variax = (struct usb_line6_variax *)line6;
 
-	/* ALSA audio interface: */
-	snd_card_register(variax->line6.card);
+	switch (variax->startup_progress) {
+	case VARIAX_STARTUP_VERSIONREQ:
+		/* repeat request until getting the response */
+		schedule_delayed_work(&line6->startup_work,
+				      msecs_to_jiffies(VARIAX_STARTUP_DELAY1));
+		/* request firmware version: */
+		line6_version_request_async(line6);
+		break;
+	case VARIAX_STARTUP_ACTIVATE:
+		/* activate device: */
+		variax_activate_async(variax, 1);
+		variax->startup_progress = VARIAX_STARTUP_SETUP;
+		schedule_delayed_work(&line6->startup_work,
+				      msecs_to_jiffies(VARIAX_STARTUP_DELAY4));
+		break;
+	case VARIAX_STARTUP_SETUP:
+		/* ALSA audio interface: */
+		snd_card_register(variax->line6.card);
+		break;
+	}
 }
 
 /*
@@ -186,11 +126,19 @@ static void line6_variax_process_message(struct usb_line6 *line6)
 	case LINE6_SYSEX_BEGIN:
 		if (memcmp(buf + 1, variax_init_version + 1,
 			   sizeof(variax_init_version) - 1) == 0) {
-			variax_startup3(variax);
+			if (variax->startup_progress >= VARIAX_STARTUP_ACTIVATE)
+				break;
+			variax->startup_progress = VARIAX_STARTUP_ACTIVATE;
+			cancel_delayed_work(&line6->startup_work);
+			schedule_delayed_work(&line6->startup_work,
+					      msecs_to_jiffies(VARIAX_STARTUP_DELAY3));
 		} else if (memcmp(buf + 1, variax_init_done + 1,
 				  sizeof(variax_init_done) - 1) == 0) {
 			/* notify of complete initialization: */
-			variax_startup4(&variax->startup_timer2);
+			if (variax->startup_progress >= VARIAX_STARTUP_SETUP)
+				break;
+			cancel_delayed_work(&line6->startup_work);
+			schedule_delayed_work(&line6->startup_work, 0);
 		}
 		break;
 	}
@@ -203,10 +151,6 @@ static void line6_variax_disconnect(struct usb_line6 *line6)
 {
 	struct usb_line6_variax *variax = (struct usb_line6_variax *)line6;
 
-	del_timer(&variax->startup_timer1);
-	del_timer(&variax->startup_timer2);
-	cancel_work_sync(&variax->startup_work);
-
 	kfree(variax->buffer_activate);
 }
 
@@ -221,10 +165,7 @@ static int variax_init(struct usb_line6 *line6,
 
 	line6->process_message = line6_variax_process_message;
 	line6->disconnect = line6_variax_disconnect;
-
-	timer_setup(&variax->startup_timer1, NULL, 0);
-	timer_setup(&variax->startup_timer2, NULL, 0);
-	INIT_WORK(&variax->startup_work, variax_startup6);
+	line6->startup = variax_startup;
 
 	/* initialize USB buffers: */
 	variax->buffer_activate = kmemdup(variax_activate,
@@ -239,7 +180,8 @@ static int variax_init(struct usb_line6 *line6,
 		return err;
 
 	/* initiate startup procedure: */
-	variax_startup1(variax);
+	schedule_delayed_work(&line6->startup_work,
+			      msecs_to_jiffies(VARIAX_STARTUP_DELAY1));
 	return 0;
 }
 
-- 
2.16.4

[PATCH v2 4/5] ALSA: line6: Drop superfluous timer helper function

[Takashi Iwai]

Now all timer usages in line6 drivers are gone, we can get rid of some
helper macro and function that became superfluous.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/usb/line6/driver.c | 11 -----------
 sound/usb/line6/driver.h |  9 ---------
 2 files changed, 20 deletions(-)

diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c
index 2b57854335b3..79e96b269411 100644
--- a/sound/usb/line6/driver.c
+++ b/sound/usb/line6/driver.c
@@ -195,17 +195,6 @@ static int line6_send_raw_message_async_part(struct message *msg,
 	return retval;
 }
 
-/*
-	Setup and start timer.
-*/
-void line6_start_timer(struct timer_list *timer, unsigned long msecs,
-		       void (*function)(struct timer_list *t))
-{
-	timer->function = function;
-	mod_timer(timer, jiffies + msecs_to_jiffies(msecs));
-}
-EXPORT_SYMBOL_GPL(line6_start_timer);
-
 /*
 	Asynchronously send raw message.
 */
diff --git a/sound/usb/line6/driver.h b/sound/usb/line6/driver.h
index 650d909c9c4f..4eb66cdf1ece 100644
--- a/sound/usb/line6/driver.h
+++ b/sound/usb/line6/driver.h
@@ -68,13 +68,6 @@
 
 #define LINE6_CHANNEL_MASK 0x0f
 
-#define CHECK_STARTUP_PROGRESS(x, n)	\
-do {					\
-	if ((x) >= (n))			\
-		return;			\
-	x = (n);			\
-} while (0)
-
 extern const unsigned char line6_midi_id[3];
 
 static const int SYSEX_DATA_OFS = sizeof(line6_midi_id) + 3;
@@ -201,8 +194,6 @@ extern int line6_send_sysex_message(struct usb_line6 *line6,
 				    const char *buffer, int size);
 extern ssize_t line6_set_raw(struct device *dev, struct device_attribute *attr,
 			     const char *buf, size_t count);
-extern void line6_start_timer(struct timer_list *timer, unsigned long msecs,
-			      void (*function)(struct timer_list *t));
 extern int line6_version_request_async(struct usb_line6 *line6);
 extern int line6_write_data(struct usb_line6 *line6, unsigned address,
 			    void *data, unsigned datalen);
-- 
2.16.4

[PATCH v2 5/5] ALSA: line6: Use container_of()

[Takashi Iwai]

... instead of unconditional cast.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/usb/line6/pod.c      | 12 +++++++-----
 sound/usb/line6/podhd.c    |  8 +++++---
 sound/usb/line6/toneport.c | 14 +++++++-------
 sound/usb/line6/variax.c   | 10 ++++++----
 4 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/sound/usb/line6/pod.c b/sound/usb/line6/pod.c
index 995e6ccc8122..9ea720b4b2ab 100644
--- a/sound/usb/line6/pod.c
+++ b/sound/usb/line6/pod.c
@@ -74,6 +74,8 @@ struct usb_line6_pod {
 	int device_id;
 };
 
+#define line6_to_pod(x)		container_of(x, struct usb_line6_pod, line6)
+
 #define POD_SYSEX_CODE 3
 
 /* *INDENT-OFF* */
@@ -177,7 +179,7 @@ static char *pod_alloc_sysex_buffer(struct usb_line6_pod *pod, int code,
 */
 static void line6_pod_process_message(struct usb_line6 *line6)
 {
-	struct usb_line6_pod *pod = (struct usb_line6_pod *) line6;
+	struct usb_line6_pod *pod = line6_to_pod(line6);
 	const unsigned char *buf = pod->line6.buffer_message;
 
 	if (memcmp(buf, pod_version_header, sizeof(pod_version_header)) == 0) {
@@ -274,7 +276,7 @@ static ssize_t device_id_show(struct device *dev,
 
 static void pod_startup(struct usb_line6 *line6)
 {
-	struct usb_line6_pod *pod = (struct usb_line6_pod *) line6;
+	struct usb_line6_pod *pod = line6_to_pod(line6);
 
 	switch (pod->startup_progress) {
 	case POD_STARTUP_VERSIONREQ:
@@ -328,7 +330,7 @@ static int snd_pod_control_monitor_get(struct snd_kcontrol *kcontrol,
 				       struct snd_ctl_elem_value *ucontrol)
 {
 	struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
-	struct usb_line6_pod *pod = (struct usb_line6_pod *)line6pcm->line6;
+	struct usb_line6_pod *pod = line6_to_pod(line6pcm->line6);
 
 	ucontrol->value.integer.value[0] = pod->monitor_level;
 	return 0;
@@ -339,7 +341,7 @@ static int snd_pod_control_monitor_put(struct snd_kcontrol *kcontrol,
 				       struct snd_ctl_elem_value *ucontrol)
 {
 	struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
-	struct usb_line6_pod *pod = (struct usb_line6_pod *)line6pcm->line6;
+	struct usb_line6_pod *pod = line6_to_pod(line6pcm->line6);
 
 	if (ucontrol->value.integer.value[0] == pod->monitor_level)
 		return 0;
@@ -368,7 +370,7 @@ static int pod_init(struct usb_line6 *line6,
 		    const struct usb_device_id *id)
 {
 	int err;
-	struct usb_line6_pod *pod = (struct usb_line6_pod *) line6;
+	struct usb_line6_pod *pod = line6_to_pod(line6);
 
 	line6->process_message = line6_pod_process_message;
 	line6->startup = pod_startup;
diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c
index 722fc5db09c5..395ae1692f45 100644
--- a/sound/usb/line6/podhd.c
+++ b/sound/usb/line6/podhd.c
@@ -44,6 +44,8 @@ struct usb_line6_podhd {
 	int firmware_version;
 };
 
+#define line6_to_podhd(x)	container_of(x, struct usb_line6_podhd, line6)
+
 static struct snd_ratden podhd_ratden = {
 	.num_min = 48000,
 	.num_max = 48000,
@@ -231,7 +233,7 @@ static int podhd_dev_start(struct usb_line6_podhd *pod)
 
 static void podhd_startup(struct usb_line6 *line6)
 {
-	struct usb_line6_podhd *pod = (struct usb_line6_podhd *)line6;
+	struct usb_line6_podhd *pod = line6_to_podhd(line6);
 
 	podhd_dev_start(pod);
 	line6_read_serial_number(&pod->line6, &pod->serial_number);
@@ -241,7 +243,7 @@ static void podhd_startup(struct usb_line6 *line6)
 
 static void podhd_disconnect(struct usb_line6 *line6)
 {
-	struct usb_line6_podhd *pod = (struct usb_line6_podhd *)line6;
+	struct usb_line6_podhd *pod = line6_to_podhd(line6);
 
 	if (pod->line6.properties->capabilities & LINE6_CAP_CONTROL_INFO) {
 		struct usb_interface *intf;
@@ -260,7 +262,7 @@ static int podhd_init(struct usb_line6 *line6,
 		      const struct usb_device_id *id)
 {
 	int err;
-	struct usb_line6_podhd *pod = (struct usb_line6_podhd *) line6;
+	struct usb_line6_podhd *pod = line6_to_podhd(line6);
 	struct usb_interface *intf;
 
 	line6->disconnect = podhd_disconnect;
diff --git a/sound/usb/line6/toneport.c b/sound/usb/line6/toneport.c
index 55865f7e437d..94a9764110d3 100644
--- a/sound/usb/line6/toneport.c
+++ b/sound/usb/line6/toneport.c
@@ -61,6 +61,8 @@ struct usb_line6_toneport {
 	struct toneport_led leds[2];
 };
 
+#define line6_to_toneport(x) container_of(x, struct usb_line6_toneport, line6)
+
 static int toneport_send_cmd(struct usb_device *usbdev, int cmd1, int cmd2);
 
 #define TONEPORT_PCM_DELAY 1
@@ -211,8 +213,8 @@ static int snd_toneport_source_get(struct snd_kcontrol *kcontrol,
 				   struct snd_ctl_elem_value *ucontrol)
 {
 	struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
-	struct usb_line6_toneport *toneport =
-	    (struct usb_line6_toneport *)line6pcm->line6;
+	struct usb_line6_toneport *toneport = line6_to_toneport(line6pcm->line6);
+
 	ucontrol->value.enumerated.item[0] = toneport->source;
 	return 0;
 }
@@ -222,8 +224,7 @@ static int snd_toneport_source_put(struct snd_kcontrol *kcontrol,
 				   struct snd_ctl_elem_value *ucontrol)
 {
 	struct snd_line6_pcm *line6pcm = snd_kcontrol_chip(kcontrol);
-	struct usb_line6_toneport *toneport =
-	    (struct usb_line6_toneport *)line6pcm->line6;
+	struct usb_line6_toneport *toneport = line6_to_toneport(line6pcm->line6);
 	unsigned int source;
 
 	source = ucontrol->value.enumerated.item[0];
@@ -397,8 +398,7 @@ static int toneport_setup(struct usb_line6_toneport *toneport)
 */
 static void line6_toneport_disconnect(struct usb_line6 *line6)
 {
-	struct usb_line6_toneport *toneport =
-		(struct usb_line6_toneport *)line6;
+	struct usb_line6_toneport *toneport = line6_to_toneport(line6);
 
 	if (toneport_has_led(toneport))
 		toneport_remove_leds(toneport);
@@ -412,7 +412,7 @@ static int toneport_init(struct usb_line6 *line6,
 			 const struct usb_device_id *id)
 {
 	int err;
-	struct usb_line6_toneport *toneport =  (struct usb_line6_toneport *) line6;
+	struct usb_line6_toneport *toneport = line6_to_toneport(line6);
 
 	toneport->type = id->driver_info;
 
diff --git a/sound/usb/line6/variax.c b/sound/usb/line6/variax.c
index fb114156b7ca..0d0de907d497 100644
--- a/sound/usb/line6/variax.c
+++ b/sound/usb/line6/variax.c
@@ -47,6 +47,8 @@ struct usb_line6_variax {
 	int startup_progress;
 };
 
+#define line6_to_variax(x)	container_of(x, struct usb_line6_variax, line6)
+
 #define VARIAX_OFFSET_ACTIVATE 7
 
 /*
@@ -86,7 +88,7 @@ static void variax_activate_async(struct usb_line6_variax *variax, int a)
 
 static void variax_startup(struct usb_line6 *line6)
 {
-	struct usb_line6_variax *variax = (struct usb_line6_variax *)line6;
+	struct usb_line6_variax *variax = line6_to_variax(line6);
 
 	switch (variax->startup_progress) {
 	case VARIAX_STARTUP_VERSIONREQ:
@@ -115,7 +117,7 @@ static void variax_startup(struct usb_line6 *line6)
 */
 static void line6_variax_process_message(struct usb_line6 *line6)
 {
-	struct usb_line6_variax *variax = (struct usb_line6_variax *) line6;
+	struct usb_line6_variax *variax = line6_to_variax(line6);
 	const unsigned char *buf = variax->line6.buffer_message;
 
 	switch (buf[0]) {
@@ -149,7 +151,7 @@ static void line6_variax_process_message(struct usb_line6 *line6)
 */
 static void line6_variax_disconnect(struct usb_line6 *line6)
 {
-	struct usb_line6_variax *variax = (struct usb_line6_variax *)line6;
+	struct usb_line6_variax *variax = line6_to_variax(line6);
 
 	kfree(variax->buffer_activate);
 }
@@ -160,7 +162,7 @@ static void line6_variax_disconnect(struct usb_line6 *line6)
 static int variax_init(struct usb_line6 *line6,
 		       const struct usb_device_id *id)
 {
-	struct usb_line6_variax *variax = (struct usb_line6_variax *) line6;
+	struct usb_line6_variax *variax = line6_to_variax(line6);
 	int err;
 
 	line6->process_message = line6_variax_process_message;
-- 
2.16.4