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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-15 22:58:58 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-15 22:58:58 +0300
commit486088bc4689f826b80aa317b45ac9e42e8b25ee (patch)
treeadf5847a6119d24da990d9e336f005c4a316e6be /Documentation/isa.txt
parent52f6c588c77b76d548201470c2a28263a41b462b (diff)
parent43e5f7e1fa66531777c49791014c3124ea9208d8 (diff)
downloadlinux-486088bc4689f826b80aa317b45ac9e42e8b25ee.tar.xz
Merge tag 'standardize-docs' of git://git.lwn.net/linux
Pull documentation format standardization from Jonathan Corbet: "This series converts a number of top-level documents to the RST format without incorporating them into the Sphinx tree. The hope is to bring some uniformity to kernel documentation and, perhaps more importantly, have our existing docs serve as an example of the desired formatting for those that will be added later. Mauro has gone through and fixed up a lot of top-level documentation files to make them conform to the RST format, but without moving or renaming them in any way. This will help when we incorporate the ones we want to keep into the Sphinx doctree, but the real purpose is to bring a bit of uniformity to our documentation and let the top-level docs serve as examples for those writing new ones" * tag 'standardize-docs' of git://git.lwn.net/linux: (84 commits) docs: kprobes.txt: Fix whitespacing tee.txt: standardize document format cgroup-v2.txt: standardize document format dell_rbu.txt: standardize document format zorro.txt: standardize document format xz.txt: standardize document format xillybus.txt: standardize document format vfio.txt: standardize document format vfio-mediated-device.txt: standardize document format unaligned-memory-access.txt: standardize document format this_cpu_ops.txt: standardize document format svga.txt: standardize document format static-keys.txt: standardize document format smsc_ece1099.txt: standardize document format SM501.txt: standardize document format siphash.txt: standardize document format sgi-ioc4.txt: standardize document format SAK.txt: standardize document format rpmsg.txt: standardize document format robust-futexes.txt: standardize document format ...
Diffstat (limited to 'Documentation/isa.txt')
-rw-r--r--Documentation/isa.txt53
1 files changed, 27 insertions, 26 deletions
diff --git a/Documentation/isa.txt b/Documentation/isa.txt
index f232c26a40be..def4a7b690b5 100644
--- a/Documentation/isa.txt
+++ b/Documentation/isa.txt
@@ -1,5 +1,6 @@
+===========
ISA Drivers
------------
+===========
The following text is adapted from the commit message of the initial
commit of the ISA bus driver authored by Rene Herman.
@@ -23,17 +24,17 @@ that all device creation has been made internal as well.
The usage model this provides is nice, and has been acked from the ALSA
side by Takashi Iwai and Jaroslav Kysela. The ALSA driver module_init's
-now (for oldisa-only drivers) become:
+now (for oldisa-only drivers) become::
-static int __init alsa_card_foo_init(void)
-{
- return isa_register_driver(&snd_foo_isa_driver, SNDRV_CARDS);
-}
+ static int __init alsa_card_foo_init(void)
+ {
+ return isa_register_driver(&snd_foo_isa_driver, SNDRV_CARDS);
+ }
-static void __exit alsa_card_foo_exit(void)
-{
- isa_unregister_driver(&snd_foo_isa_driver);
-}
+ static void __exit alsa_card_foo_exit(void)
+ {
+ isa_unregister_driver(&snd_foo_isa_driver);
+ }
Quite like the other bus models therefore. This removes a lot of
duplicated init code from the ALSA ISA drivers.
@@ -47,11 +48,11 @@ parameter, indicating how many devices to create and call our methods
with.
The platform_driver callbacks are called with a platform_device param;
-the isa_driver callbacks are being called with a "struct device *dev,
-unsigned int id" pair directly -- with the device creation completely
+the isa_driver callbacks are being called with a ``struct device *dev,
+unsigned int id`` pair directly -- with the device creation completely
internal to the bus it's much cleaner to not leak isa_dev's by passing
them in at all. The id is the only thing we ever want other then the
-struct device * anyways, and it makes for nicer code in the callbacks as
+struct device anyways, and it makes for nicer code in the callbacks as
well.
With this additional .match() callback ISA drivers have all options. If
@@ -75,20 +76,20 @@ This exports only two functions; isa_{,un}register_driver().
isa_register_driver() register's the struct device_driver, and then
loops over the passed in ndev creating devices and registering them.
-This causes the bus match method to be called for them, which is:
+This causes the bus match method to be called for them, which is::
-int isa_bus_match(struct device *dev, struct device_driver *driver)
-{
- struct isa_driver *isa_driver = to_isa_driver(driver);
+ int isa_bus_match(struct device *dev, struct device_driver *driver)
+ {
+ struct isa_driver *isa_driver = to_isa_driver(driver);
- if (dev->platform_data == isa_driver) {
- if (!isa_driver->match ||
- isa_driver->match(dev, to_isa_dev(dev)->id))
- return 1;
- dev->platform_data = NULL;
- }
- return 0;
-}
+ if (dev->platform_data == isa_driver) {
+ if (!isa_driver->match ||
+ isa_driver->match(dev, to_isa_dev(dev)->id))
+ return 1;
+ dev->platform_data = NULL;
+ }
+ return 0;
+ }
The first thing this does is check if this device is in fact one of this
driver's devices by seeing if the device's platform_data pointer is set
@@ -102,7 +103,7 @@ well.
Then, if the the driver did not provide a .match, it matches. If it did,
the driver match() method is called to determine a match.
-If it did _not_ match, dev->platform_data is reset to indicate this to
+If it did **not** match, dev->platform_data is reset to indicate this to
isa_register_driver which can then unregister the device again.
If during all this, there's any error, or no devices matched at all