ASoC: txx9: Replace tasklet with work

The tasklet is an old API that should be deprecated, usually can be
converted to another decent API.  In ASoC TXx9 ACLC driver, a tasklet
is still used for offloading the hardware reset function.  It can be
achieved gracefully with a work queued, too.

This patch replaces the tasklet usage in TXx9 ACLC driver with a
simple work.  The conversion is fairly straightforward.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200903104749.21435-4-tiwai@suse.de
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/txx9/txx9aclc.c

@@ -102,7 +102,7 @@ static void txx9aclc_dma_complete(void *arg)
 	if (dmadata->frag_count >= 0) {
 		dmadata->dmacount--;
 		if (!WARN_ON(dmadata->dmacount < 0))
-			tasklet_schedule(&dmadata->tasklet);
+			queue_work(system_highpri_wq, &dmadata->work);
 	}
 	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 }
@@ -134,9 +134,10 @@ txx9aclc_dma_submit(struct txx9aclc_dmadata *dmadata, dma_addr_t buf_dma_addr)
 
 #define NR_DMA_CHAIN		2
 
-static void txx9aclc_dma_tasklet(struct tasklet_struct *t)
+static void txx9aclc_dma_work(struct work_struct *work)
 {
-	struct txx9aclc_dmadata *dmadata = from_tasklet(dmadata, t, tasklet);
+	struct txx9aclc_dmadata *dmadata =
+		container_of(work, struct txx9aclc_dmadata, work);
 	struct dma_chan *chan = dmadata->dma_chan;
 	struct dma_async_tx_descriptor *desc;
 	struct snd_pcm_substream *substream = dmadata->substream;
@@ -208,7 +209,7 @@ static int txx9aclc_pcm_trigger(struct snd_soc_component *component,
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 		dmadata->frag_count = -1;
-		tasklet_schedule(&dmadata->tasklet);
+		queue_work(system_highpri_wq, &dmadata->work);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
@@ -352,7 +353,7 @@ static int txx9aclc_dma_init(struct txx9aclc_soc_device *dev,
 			"playback" : "capture");
 		return -EBUSY;
 	}
-	tasklet_setup(&dmadata->tasklet, txx9aclc_dma_tasklet);
+	INIT_WORK(&dmadata->work, txx9aclc_dma_work);
 	return 0;
 }
 

sound/soc/txx9/txx9aclc.h

@@ -43,7 +43,7 @@ struct txx9aclc_dmadata {
 	struct resource *dma_res;
 	struct txx9dmac_slave dma_slave;
 	struct dma_chan *dma_chan;
-	struct tasklet_struct tasklet;
+	struct work_struct work;
 	spinlock_t dma_lock;
 	int stream; /* SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE */
 	struct snd_pcm_substream *substream;