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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/Documentation/serial/serial-rs485.txt
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/Documentation/serial/serial-rs485.txt')
-rw-r--r--kernel/Documentation/serial/serial-rs485.txt50
1 files changed, 5 insertions, 45 deletions
diff --git a/kernel/Documentation/serial/serial-rs485.txt b/kernel/Documentation/serial/serial-rs485.txt
index 39dac9542..2253b8b45 100644
--- a/kernel/Documentation/serial/serial-rs485.txt
+++ b/kernel/Documentation/serial/serial-rs485.txt
@@ -33,50 +33,10 @@
the values given by the device tree.
Any driver for devices capable of working both as RS232 and RS485 should
- provide at least the following ioctls:
-
- - TIOCSRS485 (typically associated with number 0x542F). This ioctl is used
- to enable/disable RS485 mode from user-space
-
- - TIOCGRS485 (typically associated with number 0x542E). This ioctl is used
- to get RS485 mode from kernel-space (i.e., driver) to user-space.
-
- In other words, the serial driver should contain a code similar to the next
- one:
-
- static struct uart_ops atmel_pops = {
- /* ... */
- .ioctl = handle_ioctl,
- };
-
- static int handle_ioctl(struct uart_port *port,
- unsigned int cmd,
- unsigned long arg)
- {
- struct serial_rs485 rs485conf;
-
- switch (cmd) {
- case TIOCSRS485:
- if (copy_from_user(&rs485conf,
- (struct serial_rs485 *) arg,
- sizeof(rs485conf)))
- return -EFAULT;
-
- /* ... */
- break;
-
- case TIOCGRS485:
- if (copy_to_user((struct serial_rs485 *) arg,
- ...,
- sizeof(rs485conf)))
- return -EFAULT;
- /* ... */
- break;
-
- /* ... */
- }
- }
-
+ implement the rs485_config callback in the uart_port structure. The
+ serial_core calls rs485_config to do the device specific part in response
+ to TIOCSRS485 and TIOCGRS485 ioctls (see below). The rs485_config callback
+ receives a pointer to struct serial_rs485.
4. USAGE FROM USER-LEVEL
@@ -85,7 +45,7 @@
#include <linux/serial.h>
- /* Driver-specific ioctls: */
+ /* RS485 ioctls: */
#define TIOCGRS485 0x542E
#define TIOCSRS485 0x542F