linux/drivers
Douglas Anderson ef0eebc051 drivers/pinctrl: Add the concept of an "init" state
For pinctrl the "default" state is applied to pins before the driver's
probe function is called.  This is normally a sensible thing to do,
but in some cases can cause problems.  That's because the pins will
change state before the driver is given a chance to program how those
pins should behave.

As an example you might have a regulator that is controlled by a PWM
(output high = high voltage, output low = low voltage).  The firmware
might leave this pin as driven high.  If we allow the driver core to
reconfigure this pin as a PWM pin before the PWM's probe function runs
then you might end up running at too low of a voltage while we probe.

Let's introudce a new "init" state.  If this is defined we'll set
pinctrl to this state before probe and then "default" after probe
(unless the driver explicitly changed states already).

An alternative idea that was thought of was to use the pre-existing
"sleep" or "idle" states and add a boolean property that we should
start in that mode.  This was not done because the "init" state is
needed for correctness and those other states are only present (and
only transitioned in to and out of) when (optional) power management
is enabled.

Changes in v3:
- Moved declarations to pinctrl/devinfo.h
- Fixed author/SoB

Changes in v2:
- Added comment to pinctrl_init_done() as per Linus W.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-10-27 11:24:23 +01:00
..
accessibility
acpi ACPI: Eliminate CONFIG_.*{, _MODULE} #ifdef in favor of IS_ENABLED() 2015-09-15 03:05:45 +02:00
amba
android mm: mark most vm_operations_struct const 2015-09-10 13:29:01 -07:00
ata Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-09-03 16:55:55 -07:00
atm
auxdisplay
base drivers/pinctrl: Add the concept of an "init" state 2015-10-27 11:24:23 +01:00
bcma
block Merge branch 'for-linus' of git://git.kernel.dk/linux-block 2015-09-19 18:57:09 -07:00
bluetooth Bluetooth: hci_bcm: Fix crash on suspend 2015-08-28 21:09:14 +02:00
bus regmap: Changes for v4.3 2015-09-08 16:48:55 -07:00
cdrom
char IPMI updates for 4.3 2015-09-08 18:19:17 -07:00
clk A few driver fixes for tegra, rockchip, and st SoCs and a two-liner 2015-09-19 20:17:40 -07:00
clocksource - New Device Support 2015-09-04 11:35:03 -07:00
connector
cpufreq cpufreq: acpi-cpufreq: Use cpufreq_cpu_get_raw() in ->get() 2015-09-16 02:17:49 +02:00
cpuidle Additional power management and ACPI material for v4.3-rc1 2015-09-11 19:11:06 -07:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-09-16 07:53:33 -07:00
dca
devfreq PM / devfreq: Fix incorrect type issue. 2015-09-11 14:23:30 +09:00
dio
dma genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
dma-buf
edac edac updates for v4.3-rc1 2015-09-11 16:21:12 -07:00
eisa
extcon regulator: Updates for v4.3 2015-08-31 15:49:19 -07:00
firewire
firmware kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
fmc
gpio Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-18 08:11:42 -07:00
gpu gpu/drm: Kill off set_irq_flags usage 2015-09-16 16:53:38 +02:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2015-09-04 12:02:11 -07:00
hsi mm: mark most vm_operations_struct const 2015-09-10 13:29:01 -07:00
hv
hwmon hwmon: (nct6775) Add support for NCT6793D 2015-09-12 19:43:02 -07:00
hwspinlock
hwtracing/coresight
i2c Merge branch 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2015-09-08 16:16:26 -07:00
ide
idle
iio This is the bulk of GPIO changes for the v4.3 kernel cycle: 2015-09-04 10:07:45 -07:00
infiniband Changes for 4.3-rc1 2015-09-16 09:16:20 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2015-09-11 19:17:28 -07:00
iommu fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void 2015-09-11 15:21:34 -07:00
ipack
irqchip irqchip: Kill off set_irq_flags usage 2015-09-16 16:53:38 +02:00
isdn libnvdimm for 4.3: 2015-09-08 14:35:59 -07:00
leds leds:lp55xx: Correct Kconfig dependency for f/w user helper 2015-09-17 10:02:20 +02:00
lguest
macintosh powerpc updates for 4.3 2015-09-03 16:41:38 -07:00
mailbox Merge branch 'mailbox-for-next' of git://git.linaro.org/landing-teams/working/fujitsu/integration 2015-09-05 18:11:04 -07:00
mcb
md SCSI misc on 20150911 2015-09-11 18:15:18 -07:00
media media updates for v4.3-rc1 2015-09-11 16:42:39 -07:00
memory IOMMU Updates for Linux v4.3 2015-09-08 17:22:35 -07:00
memstick
message
mfd genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
misc powerpc fixes for 4.3 2015-09-18 08:01:06 -07:00
mmc MMC core: 2015-09-08 16:33:16 -07:00
mtd MTD updates #2 for 4.3-rc1: 2015-09-09 11:17:33 -07:00
net net/mlx4_en: Use access helper irq_data_get_affinity_mask() 2015-09-15 17:06:28 +02:00
nfc This is the bulk of GPIO changes for the v4.3 kernel cycle: 2015-09-04 10:07:45 -07:00
ntb NTB: Fix range check on memory window index 2015-09-07 15:27:12 -04:00
nubus
nvdimm pmem: add proper fencing to pmem_rw_page() 2015-09-17 11:49:28 -04:00
nvmem
of Merge branch 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2015-09-08 16:16:26 -07:00
oprofile
parisc parisc: use seq_hex_dump() to dump buffers 2015-09-10 13:29:01 -07:00
parport
pci genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
pcmcia pcmcia: soc_common: remove skt_dev_info's clk pointer 2015-09-03 16:01:03 +01:00
perf
phy This is the bulk of GPIO changes for the v4.3 kernel cycle: 2015-09-04 10:07:45 -07:00
pinctrl drivers/pinctrl: Add the concept of an "init" state 2015-10-27 11:24:23 +01:00
platform platform-drivers-x86 for 4.3-2 2015-09-17 21:41:02 -07:00
pnp
power power supply and reset fixes for the v4.3 series 2015-09-17 12:25:42 -07:00
powercap powercap / RAPL: disable the 2nd power limit properly 2015-08-29 01:46:40 +02:00
pps
ps3
ptp
pwm pwm: Changes for v4.3-rc1 2015-09-09 10:55:32 -07:00
rapidio
ras
regulator regmap: Changes for v4.3 2015-09-08 16:48:55 -07:00
remoteproc
reset reset: ath79: Fix missing spin_lock_init 2015-09-01 14:48:40 +02:00
rpmsg
rtc rtc: abx80x: fix RTC write bit 2015-09-05 19:37:31 +02:00
s390 virtio: fixes on top of 4.3-rc1 2015-09-18 09:28:20 -07:00
sbus
scsi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-09-11 19:00:42 -07:00
sfi
sh sh: Kill off set_irq_flags usage 2015-09-16 16:53:39 +02:00
sn
soc genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
spi Merge remote-tracking branches 'spi/topic/ti-qspi', 'spi/topic/xcomm' and 'spi/topic/xlp' into spi-next 2015-08-31 14:45:45 +01:00
spmi genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
ssb
staging Changes for 4.3-rc1 2015-09-19 20:04:11 -07:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-09-11 19:00:42 -07:00
tc
thermal thermal: fix intel PCH thermal driver mismerge 2015-09-11 20:06:59 -07:00
thunderbolt
tty xen: MFN/GFN/BFN terminology changes for 4.3-rc0 2015-09-10 16:21:11 -07:00
uio
usb usb: renesas_usbhs: Remove unneeded #include <linux/platform_data/gpio-rcar.h> 2015-10-20 16:03:36 +02:00
uwb
vfio
vhost virtio: fixes on top of 4.3-rc1 2015-09-18 09:28:20 -07:00
video Merge branch 'akpm' (patches from Andrew) 2015-09-10 18:19:42 -07:00
virt
virtio virtio_balloon: do not change memory amount visible via /proc/meminfo 2015-09-08 13:32:11 +03:00
vlynq
vme
w1 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2015-09-01 18:46:42 -07:00
watchdog Merge git://www.linux-watchdog.org/linux-watchdog 2015-09-11 15:12:59 -07:00
xen Merge branch 'akpm' (patches from Andrew) 2015-09-10 18:19:42 -07:00
zorro
Kconfig Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-09-03 16:27:01 -07:00
Makefile This is the bulk of pin control changes for the v4.3 development 2015-09-04 10:22:09 -07:00