This "change_port" part of uart_set_info() is for no good reason
inlined there. It makes the function rather hard to read. Therefore,
extract it to a separate function.
This allows for flattening the ifs (with short path "return"s) and
avoiding two levels of indentation. Both making the code really flat and
comprehesible.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>
---
drivers/tty/serial/serial_core.c | 114 ++++++++++++++++---------------
1 file changed, 58 insertions(+), 56 deletions(-)
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index ce3cf95fc910..c472594c3a9f 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -834,6 +834,61 @@ static int uart_get_info_user(struct tty_struct *tty,
return uart_get_info(port, ss) < 0 ? -EIO : 0;
}
+static int uart_change_port(struct uart_port *uport,
+ const struct serial_struct *new_info,
+ unsigned long new_port)
+{
+ unsigned long old_iobase, old_mapbase;
+ unsigned int old_type, old_iotype, old_hub6, old_shift;
+ int retval;
+
+ old_iobase = uport->iobase;
+ old_mapbase = uport->mapbase;
+ old_type = uport->type;
+ old_hub6 = uport->hub6;
+ old_iotype = uport->iotype;
+ old_shift = uport->regshift;
+
+ if (old_type != PORT_UNKNOWN && uport->ops->release_port)
+ uport->ops->release_port(uport);
+
+ uport->iobase = new_port;
+ uport->type = new_info->type;
+ uport->hub6 = new_info->hub6;
+ uport->iotype = new_info->io_type;
+ uport->regshift = new_info->iomem_reg_shift;
+ uport->mapbase = (unsigned long)new_info->iomem_base;
+
+ if (uport->type == PORT_UNKNOWN || !uport->ops->request_port)
+ return 0;
+
+ retval = uport->ops->request_port(uport);
+ if (retval == 0)
+ return 0; /* succeeded => done */
+
+ /*
+ * If we fail to request resources for the new port, try to restore the
+ * old settings.
+ */
+ uport->iobase = old_iobase;
+ uport->type = old_type;
+ uport->hub6 = old_hub6;
+ uport->iotype = old_iotype;
+ uport->regshift = old_shift;
+ uport->mapbase = old_mapbase;
+
+ if (old_type == PORT_UNKNOWN)
+ return retval;
+
+ retval = uport->ops->request_port(uport);
+ /* If we failed to restore the old settings, we fail like this. */
+ if (retval)
+ uport->type = PORT_UNKNOWN;
+
+ /* We failed anyway. */
+ return -EBUSY;
+}
+
static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
struct uart_state *state,
struct serial_struct *new_info)
@@ -930,62 +985,9 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
}
if (change_port) {
- unsigned long old_iobase, old_mapbase;
- unsigned int old_type, old_iotype, old_hub6, old_shift;
-
- old_iobase = uport->iobase;
- old_mapbase = uport->mapbase;
- old_type = uport->type;
- old_hub6 = uport->hub6;
- old_iotype = uport->iotype;
- old_shift = uport->regshift;
-
- /*
- * Free and release old regions
- */
- if (old_type != PORT_UNKNOWN && uport->ops->release_port)
- uport->ops->release_port(uport);
-
- uport->iobase = new_port;
- uport->type = new_info->type;
- uport->hub6 = new_info->hub6;
- uport->iotype = new_info->io_type;
- uport->regshift = new_info->iomem_reg_shift;
- uport->mapbase = (unsigned long)new_info->iomem_base;
-
- /*
- * Claim and map the new regions
- */
- if (uport->type != PORT_UNKNOWN && uport->ops->request_port) {
- retval = uport->ops->request_port(uport);
- /*
- * If we fail to request resources for the
- * new port, try to restore the old settings.
- */
- if (retval) {
- uport->iobase = old_iobase;
- uport->type = old_type;
- uport->hub6 = old_hub6;
- uport->iotype = old_iotype;
- uport->regshift = old_shift;
- uport->mapbase = old_mapbase;
-
- if (old_type != PORT_UNKNOWN) {
- retval = uport->ops->request_port(uport);
- /*
- * If we failed to restore the old
- * settings, we fail like this.
- */
- if (retval)
- uport->type = PORT_UNKNOWN;
-
- /* We failed anyway. */
- return -EBUSY;
- }
-
- return retval;
- }
- }
+ retval = uart_change_port(uport, new_info, new_port);
+ if (retval)
+ return retval;
}
if (change_irq)
--
2.47.1
