dmaengine: at_xdmac: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Link: https://lore.kernel.org/r/20200831103542.305571-4-allen.lkml@gmail.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/at_xdmac.c

@@ -1613,9 +1613,9 @@ static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
 	/* Then continue with usual descriptor management */
 }
 
-static void at_xdmac_tasklet(unsigned long data)
+static void at_xdmac_tasklet(struct tasklet_struct *t)
 {
-	struct at_xdmac_chan	*atchan = (struct at_xdmac_chan *)data;
+	struct at_xdmac_chan	*atchan = from_tasklet(atchan, t, tasklet);
 	struct at_xdmac_desc	*desc;
 	u32			error_mask;
 
@@ -2063,8 +2063,7 @@ static int at_xdmac_probe(struct platform_device *pdev)
 		spin_lock_init(&atchan->lock);
 		INIT_LIST_HEAD(&atchan->xfers_list);
 		INIT_LIST_HEAD(&atchan->free_descs_list);
-		tasklet_init(&atchan->tasklet, at_xdmac_tasklet,
-			     (unsigned long)atchan);
+		tasklet_setup(&atchan->tasklet, at_xdmac_tasklet);
 
 		/* Clear pending interrupts. */
 		while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))