tty: atmel_serial: 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/20200817085921.26033-3-allen.cryptic@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/atmel_serial.c

@@ -1722,10 +1722,11 @@ static int atmel_prepare_rx_pdc(struct uart_port *port)
 /*
  * tasklet handling tty stuff outside the interrupt handler.
  */
-static void atmel_tasklet_rx_func(unsigned long data)
+static void atmel_tasklet_rx_func(struct tasklet_struct *t)
 {
-	struct uart_port *port = (struct uart_port *)data;
-	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct atmel_uart_port *atmel_port = from_tasklet(atmel_port, t,
+							  tasklet_rx);
+	struct uart_port *port = &atmel_port->uart;
 
 	/* The interrupt handler does not take the lock */
 	spin_lock(&port->lock);
@@ -1733,10 +1734,11 @@ static void atmel_tasklet_rx_func(unsigned long data)
 	spin_unlock(&port->lock);
 }
 
-static void atmel_tasklet_tx_func(unsigned long data)
+static void atmel_tasklet_tx_func(struct tasklet_struct *t)
 {
-	struct uart_port *port = (struct uart_port *)data;
-	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct atmel_uart_port *atmel_port = from_tasklet(atmel_port, t,
+							  tasklet_tx);
+	struct uart_port *port = &atmel_port->uart;
 
 	/* The interrupt handler does not take the lock */
 	spin_lock(&port->lock);
@@ -1911,10 +1913,8 @@ static int atmel_startup(struct uart_port *port)
 	}
 
 	atomic_set(&atmel_port->tasklet_shutdown, 0);
-	tasklet_init(&atmel_port->tasklet_rx, atmel_tasklet_rx_func,
-			(unsigned long)port);
-	tasklet_init(&atmel_port->tasklet_tx, atmel_tasklet_tx_func,
-			(unsigned long)port);
+	tasklet_setup(&atmel_port->tasklet_rx, atmel_tasklet_rx_func);
+	tasklet_setup(&atmel_port->tasklet_tx, atmel_tasklet_tx_func);
 
 	/*
 	 * Initialize DMA (if necessary)