linux/arch/arm
Stephen Warren 30ca2226be ARM: tegra: always enable USB VBUS regulators
This fixes a regression exposed during the merge window by commit
9f310de "ARM: tegra: fix VBUS regulator GPIO polarity in DT"; namely that
USB VBUS doesn't get turned on, so USB devices are not detected. This
affects the internal USB port on TrimSlice (i.e. the USB->SATA bridge, to
which the SSD is connected) and the external port(s) on Seaboard/
Springbank and Whistler.

The Tegra DT as written in v3.11 allows two paths to enable USB VBUS:

1) Via the legacy DT binding for the USB controller; it can directly
   acquire a VBUS GPIO and activate it.

2) Via a regulator for VBUS, which is referenced by the new DT binding
   for the USB controller.

Those two methods both use the same GPIO, and hence whichever of the
USB controller and regulator gets probed first ends up owning the GPIO.
In practice, the USB driver only supports path (1) above, since the
patches to support the new USB binding are not present until v3.12:-(

In practice, the regulator ends up being probed first and owning the
GPIO. Since nothing enables the regulator (the USB driver code is not
yet present), the regulator ends up being turned off. This originally
caused no problem, because the polarity in the regulator definition was
incorrect, so attempting to turn off the regulator actually turned it
on, and everything worked:-(

However, when testing the new USB driver code in v3.12, I noticed the
incorrect polarity and fixed it in commit 9f310de "ARM: tegra: fix VBUS
regulator GPIO polarity in DT". In the context of v3.11, this patch then
caused the USB VBUS to actually turn off, which broke USB ports with VBUS
control. I got this patch included in v3.11-rc1 since it fixed a bug in
device tree (incorrect polarity specification), and hence was suitable to
be included early in the rc series. I evidently did not test the patch at
all, or correctly, in the context of v3.11, and hence did not notice the
issue that I have explained above:-(

Fix this by making the USB VBUS regulators always enabled. This way, if
the regulator owns the GPIO, it will always be turned on, even if there
is no USB driver code to request the regulator be turned on. Even
ignoring this bug, this is a reasonable way to configure the HW anyway.

If this patch is applied to v3.11, it will cause a couple pretty trivial
conflicts in tegra20-{trimslice,seaboard}.dts when creating v3.12, since
the context right above the added lines changed in patches destined for
v3.12.

Reported-by: Kyle McMartin <kmcmarti@redhat.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-21 21:36:19 -07:00
..
boot ARM: tegra: always enable USB VBUS regulators 2013-08-21 21:36:19 -07:00
common Merge tag 'davinci-fixes-for-v3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nsekhar/linux-davinci into fixes 2013-07-22 19:54:21 -07:00
configs ARM: multi_v7_defconfig: Select USB chipidea driver 2013-07-23 12:18:02 -07:00
crypto
include arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
kernel arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
kvm KVM fixes for 3.11 2013-07-03 13:21:40 -07:00
lib arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-at91 ARM: at91: add missing uart clocks DT entries 2013-08-14 09:26:03 +02:00
mach-bcm
mach-bcm2835 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-clps711x reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-cns3xxx reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-davinci ARM: davinci: nand: specify ecc strength 2013-08-19 09:30:20 -07:00
mach-dove Watchdog: allow orion_wdt to be built for Dove 2013-07-11 22:17:56 +02:00
mach-ebsa110 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-ep93xx reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-exynos Samsung fixes for v3.11 2013-07-24 17:06:58 -07:00
mach-footbridge ARM: footbridge: fix overlapping PCI mappings 2013-07-22 20:00:47 -07:00
mach-gemini
mach-highbank ARM: highbank: Only touch common coherency control register fields 2013-07-22 20:03:59 -07:00
mach-imx The imx fixes for 3.11: 2013-07-22 19:58:02 -07:00
mach-integrator reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-iop13xx reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-iop32x reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-iop33x
mach-ixp4xx ARM: SoC fixes for 3.11-rc 2013-07-13 15:00:26 -07:00
mach-keystone ARM: keystone: fix compilation warning 2013-07-23 11:03:54 -07:00
mach-kirkwood Watchdog: allow orion_wdt to be built for Dove 2013-07-11 22:17:56 +02:00
mach-ks8695 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-lpc32xx reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-mmp reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-msm Fixes for MSM for 3.11 2013-08-04 13:34:57 -07:00
mach-mv78xx0 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-mvebu arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-mxs Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-07-09 18:24:39 -07:00
mach-netx reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-nomadik reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-nspire arm: Add Initial TI-Nspire support 2013-06-21 20:06:30 +02:00
mach-omap1 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-omap2 ARM: OMAP: rx51: change musb mode to OTG 2013-08-16 09:40:01 -07:00
mach-orion5x Watchdog: allow orion_wdt to be built for Dove 2013-07-11 22:17:56 +02:00
mach-picoxcell reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-prima2 arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-pxa ARM: pxa: propagate errors from regulator_enable() to pxamci 2013-07-23 12:15:15 -07:00
mach-realview reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-rockchip arm: add basic support for Rockchip RK3066a boards 2013-06-21 09:21:02 +02:00
mach-rpc reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-s3c24xx Samsung fixes for v3.11 2013-07-24 17:06:58 -07:00
mach-s3c64xx reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-s5p64x0 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-s5pc100 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-s5pv210 For the 3.11 merge we only have one new MFD driver for the Kontron PLD. 2013-07-10 11:10:27 -07:00
mach-sa1100 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-shark reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-shmobile Second round of Renesas ARM based SoC fixes for v3.11 2013-08-04 13:37:49 -07:00
mach-socfpga arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-spear arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-sti ARM: STi: remove sti_secondary_start from INIT section. 2013-08-04 13:40:55 -07:00
mach-sunxi reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-tegra arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-u300 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-ux500 arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
mach-versatile reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-vexpress ARM SoC specific changes 2013-07-02 13:43:38 -07:00
mach-virt Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2013-07-03 09:46:29 -07:00
mach-vt8500 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-w90x900 reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
mach-zynq ARM: zynq: fix compilation warning 2013-07-23 11:04:04 -07:00
mm arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
net
nwfpe
oprofile
plat-iop reboot: arm: change reboot_mode to use enum reboot_mode 2013-07-09 10:33:29 -07:00
plat-omap Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-07-06 14:09:38 -07:00
plat-orion Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-07-06 14:09:38 -07:00
plat-pxa
plat-samsung ARM: SAMSUNG: fix to support for missing cpu specific map_io 2013-07-30 13:30:57 +09:00
plat-versatile arm: delete __cpuinit/__CPUINIT usage from all ARM users 2013-07-14 19:36:52 -04:00
tools
vfp
xen xen/arm and xen/arm64: implement HYPERVISOR_tmem_op 2013-07-04 11:41:12 +00:00
Kconfig ARM: EXYNOS: Update CONFIG_ARCH_NR_GPIO for Exynos 2013-07-24 18:55:27 +09:00
Kconfig-nommu ARM: mpu: Ensure that MPU depends on CPU_V7 2013-06-17 15:13:18 +01:00
Kconfig.debug Omap fixes and minor defconfig updates that would be good to 2013-07-12 10:59:39 -07:00
Makefile Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2013-07-03 09:46:29 -07:00