sc16is7xx: use kworker to update ier bits

.stop_rx/tx() are called in atomic context, we cannot use
blocking I/O. While at it correct the name of RX bit and
'*' placement in pointer declarations.

Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index f218e24..86a679a 100644 (file)
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -302,9 +302,11 @@ struct sc16is7xx_devtype {
 };
 
 #define SC16IS7XX_RECONF_MD            (1 << 0)
+#define SC16IS7XX_RECONF_IER           (1 << 1)
 
 struct sc16is7xx_one_config {
        unsigned int                    flags;
+       u8                              ier_clear;
 };
 
 struct sc16is7xx_one {
@@ -682,23 +684,30 @@ static void sc16is7xx_reg_proc(struct kthread_work *ws)
                                      SC16IS7XX_MCR_LOOP_BIT,
                                      (one->port.mctrl & TIOCM_LOOP) ?
                                      SC16IS7XX_MCR_LOOP_BIT : 0);
+
+       if (config.flags & SC16IS7XX_RECONF_IER)
+               sc16is7xx_port_update(&one->port, SC16IS7XX_IER_REG,
+                                     config.ier_clear, 0);
 }
 
-static void sc16is7xx_stop_tx(struct uart_port* port)
+static void sc16is7xx_ier_clear(struct uart_port *port, u8 bit)
 {
-       sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
-                             SC16IS7XX_IER_THRI_BIT,
-                             0);
+       struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+       struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+
+       one->config.flags |= SC16IS7XX_RECONF_IER;
+       one->config.ier_clear |= bit;
+       queue_kthread_work(&s->kworker, &one->reg_work);
 }
 
-static void sc16is7xx_stop_rx(struct uart_port* port)
+static void sc16is7xx_stop_tx(struct uart_port *port)
 {
-       struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+       sc16is7xx_ier_clear(port, SC16IS7XX_IER_THRI_BIT);
+}
 
-       one->port.read_status_mask &= ~SC16IS7XX_LSR_DR_BIT;
-       sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
-                             SC16IS7XX_LSR_DR_BIT,
-                             0);
+static void sc16is7xx_stop_rx(struct uart_port *port)
+{
+       sc16is7xx_ier_clear(port, SC16IS7XX_IER_RDI_BIT);
 }
 
 static void sc16is7xx_start_tx(struct uart_port *port)