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authorLinus Torvalds <torvalds@linux-foundation.org>2014-06-08 22:31:16 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2014-06-08 22:31:16 +0400
commit3f17ea6dea8ba5668873afa54628a91aaa3fb1c0 (patch)
treeafbeb2accd4c2199ddd705ae943995b143a0af02 /Documentation/serial/driver
parent1860e379875dfe7271c649058aeddffe5afd9d0d (diff)
parent1a5700bc2d10cd379a795fd2bb377a190af5acd4 (diff)
downloadlinux-3f17ea6dea8ba5668873afa54628a91aaa3fb1c0.tar.xz
Merge branch 'next' (accumulated 3.16 merge window patches) into master
Now that 3.15 is released, this merges the 'next' branch into 'master', bringing us to the normal situation where my 'master' branch is the merge window. * accumulated work in next: (6809 commits) ufs: sb mutex merge + mutex_destroy powerpc: update comments for generic idle conversion cris: update comments for generic idle conversion idle: remove cpu_idle() forward declarations nbd: zero from and len fields in NBD_CMD_DISCONNECT. mm: convert some level-less printks to pr_* MAINTAINERS: adi-buildroot-devel is moderated MAINTAINERS: add linux-api for review of API/ABI changes mm/kmemleak-test.c: use pr_fmt for logging fs/dlm/debug_fs.c: replace seq_printf by seq_puts fs/dlm/lockspace.c: convert simple_str to kstr fs/dlm/config.c: convert simple_str to kstr mm: mark remap_file_pages() syscall as deprecated mm: memcontrol: remove unnecessary memcg argument from soft limit functions mm: memcontrol: clean up memcg zoneinfo lookup mm/memblock.c: call kmemleak directly from memblock_(alloc|free) mm/mempool.c: update the kmemleak stack trace for mempool allocations lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations mm: introduce kmemleak_update_trace() mm/kmemleak.c: use %u to print ->checksum ...
Diffstat (limited to 'Documentation/serial/driver')
-rw-r--r--Documentation/serial/driver25
1 files changed, 25 insertions, 0 deletions
diff --git a/Documentation/serial/driver b/Documentation/serial/driver
index c3a7689a90e6..3bba1aeb799c 100644
--- a/Documentation/serial/driver
+++ b/Documentation/serial/driver
@@ -429,3 +429,28 @@ thus:
struct uart_port port;
int my_stuff;
};
+
+Modem control lines via GPIO
+----------------------------
+
+Some helpers are provided in order to set/get modem control lines via GPIO.
+
+mctrl_gpio_init(dev, idx):
+ This will get the {cts,rts,...}-gpios from device tree if they are
+ present and request them, set direction etc, and return an
+ allocated structure. devm_* functions are used, so there's no need
+ to call mctrl_gpio_free().
+
+mctrl_gpio_free(dev, gpios):
+ This will free the requested gpios in mctrl_gpio_init().
+ As devm_* function are used, there's generally no need to call
+ this function.
+
+mctrl_gpio_to_gpiod(gpios, gidx)
+ This returns the gpio structure associated to the modem line index.
+
+mctrl_gpio_set(gpios, mctrl):
+ This will sets the gpios according to the mctrl state.
+
+mctrl_gpio_get(gpios, mctrl):
+ This will update mctrl with the gpios values.