linux/arch
Linus Walleij e0fc62a655 w1: w1-gpio: Convert to use GPIO descriptors
The w1 master driver includes a complete open drain emulation
reimplementation among other things.

This converts the driver and all board files using it to use
GPIO descriptors associated with the device to look up the
GPIO wire, as well ass the optional pull-up GPIO line.

When probed from the device tree, the driver will just pick
descriptors and use them right off. For the two board files
in the kernel, we add descriptor lookups so we do not need
to keep any old platform data handling around for the GPIO
lines.

As the platform data is also a state container for this driver,
we augment it to contain the GPIO descriptors.

w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone
since this pair was a reimplementation of open drain emulation
which is now handled by gpiolib.

The special "linux,open-drain" flag is a bit of mishap here:
it has the same semantic as the same flags in I2C: it means
that something in the platform is setting up the line as
open drain behind our back. We handle this the same way as
in I2C.

To drive the pull-up, we need to bypass open drain emulation
in gpiolib for the line, and this is done by driving it high
using gpiod_set_raw_value() which has been augmented to have
the semantic of overriding the open drain emulation.

We also augment the documentation to reflect the way to pass
GPIO descriptors from the machine.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-08 15:32:53 +01:00
..
alpha treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
arc ARC updates for 4.15-rc1 2017-11-25 08:21:54 -10:00
arm w1: w1-gpio: Convert to use GPIO descriptors 2017-12-08 15:32:53 +01:00
arm64 Trimmed second batch of KVM changes for Linux 4.15 2017-11-24 19:44:25 -10:00
blackfin treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
c6x Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
cris pci-v4.15-changes 2017-11-15 15:01:28 -08:00
frv Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
h8300 mm, arch: remove empty_bad_page* 2017-11-15 18:21:03 -08:00
hexagon Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
ia64 arch/ia64/include/asm/topology.h: remove unused parent_node() macro 2017-11-17 16:10:04 -08:00
m32r m32r: fix endianness constraints 2017-11-15 18:21:00 -08:00
m68k m68k/macboing: Fix missed timer callback assignment 2017-11-24 16:19:40 +01:00
metag DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
microblaze DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
mips Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-25 08:37:16 -10:00
mn10300 bug: define the "cut here" string in a single place 2017-11-17 16:10:01 -08:00
nios2 DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
openrisc kmemcheck: remove annotations 2017-11-15 18:21:04 -08:00
parisc treewide: Switch DEFINE_TIMER callbacks to struct timer_list * 2017-11-21 15:57:05 -08:00
powerpc Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-25 08:37:16 -10:00
riscv RISC-V Port for Linux 4.15 v9 2017-11-15 10:49:15 -08:00
s390 treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
score License cleanup: add SPDX license identifier to uapi header files with no license 2017-11-02 11:19:54 +01:00
sh treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
sparc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2017-11-17 20:21:44 -08:00
tile Merge branch 'akpm' (patches from Andrew) 2017-11-17 16:56:17 -08:00
um This pull request contains the following core changes: 2017-11-22 20:46:06 -10:00
unicore32 kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2017-11-15 18:21:04 -08:00
x86 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-26 14:11:54 -08:00
xtensa libnvdimm for 4.15 2017-11-17 09:51:57 -08:00
.gitignore
Kconfig bpf: Revert bpf_overrid_function() helper changes. 2017-11-11 18:24:55 +09:00