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  1. 19 3月, 2014 2 次提交
  3. 18 3月, 2014 5 次提交
  5. 19 2月, 2014 3 次提交
  7. 28 1月, 2014 1 次提交
  9. 21 1月, 2014 7 次提交
  11. 14 1月, 2014 3 次提交
  13. 10 1月, 2014 1 次提交
  15. 07 1月, 2014 5 次提交
    • S
      mfd: input: iio: ti_amm335x: Rework TSC/ADC synchronization · 7ca6740c
      由 Sebastian Andrzej Siewior 提交于 
      The ADC driver always programs all possible ADC values and discards
them except for the value IIO asked for. On the am335x-evm the driver
programs four values and it takes 500us to gather them. Reducing the number
of conversations down to the (required) one also reduces the busy loop down
to 125us.

This leads to another error, namely the FIFOCOUNT register is sometimes
(like one out of 10 attempts) not updated in time leading to EBUSY.
The next read has the FIFOCOUNT register updated.
Checking for the ADCSTAT register for being idle isn't a good choice either.
The problem is that if TSC is used at the same time, the HW completes the
conversation for ADC *and* before the driver noticed it, the HW begins to
perform a TSC conversation and so the driver never seen the HW idle. The
next time we would have two values in the FIFO but since the driver reads
everything we always see the current one.
So instead of polling for the IDLE bit in ADCStatus register, we should
check the FIFOCOUNT register. It should be one instead of zero because we
request one value.

This change in turn leads to another error. Sometimes if TSC & ADC are
used together the TSC starts generating interrupts even if nobody
actually touched the touchscreen. The interrupts seem valid because TSC's
FIFO is filled with values for each channel of the TSC. This condition stops
after a few ADC reads but will occur again. Not good.

On top of this (even without the changes I just mentioned) there is a ADC
& TSC lockup condition which was reported to me by Jeff Lance including the
following test case:
A busy loop of "cat /sys/bus/iio/devices/iio\:device0/in_voltage4_raw"
and a mug on touch screen. With this setup, the hardware will lockup after
something between 20 minutes and it could take up to a couple of hours.
During that lockup, the ADCSTAT register says 0x30 (or 0x70) which means
STEP_ID = IDLE and FSM_BUSY = yes. That means the hardware says that it is
idle and busy at the same time which is an invalid condition.

For all this reasons I decided to rework this TSC/ADC part and add a
handshake / synchronization here:
First the ADC signals that it needs the HW and writes a 0 mask into the
SE register. The HW (if active) will complete the current conversation
and become idle. The TSC driver will gather the values from the FIFO
(woken up by an interrupt) and won't "enable" another conversation.
Instead it will wake up the ADC driver which is already waiting. The ADC
driver will start "its" conversation and once it is done, it will
enable the TSC steps so the TSC will work again.

After this rework I haven't observed the lockup so far. Plus the busy
loop has been reduced from 500us to 125us.

The continues-read mode remains unchanged.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
      7ca6740c
    • S
      mfd: ti_am335x_tscadc: Don't read back REG_SE · 7e170c6e
      由 Sebastian Andrzej Siewior 提交于 
      The purpose of reg_se_cache has been defeated. It should avoid the
read-back of the register to avoid the latency and the fact that the
bits are reset to 0 after the individual conversation took place.

The reason why this is required like this to work, is that read-back of
the register removes the bits of the ADC so they do not start another
conversation after the register is re-written from the TSC side for the
update.
To avoid the not required read-back I introduce a "set once" variant which
does not update the cache mask. After the conversation completes, the
bit is removed from the SE register anyway and we don't plan a new
conversation "any time soon". The current set function is renamed to
set_cache to distinguish the two operations.
This is a small preparation for a larger sync-rework.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
      7e170c6e
    • S
      mfd: ti_am335x_tscadc: Make am335x_tsc_se_update() local · 3466bd22
      由 Sebastian Andrzej Siewior 提交于 
      Since the "recent" changes, am335x_tsc_se_update() has no longer any
users outside of this file so make it local.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
      3466bd22
    • C
      extcon: arizona: Add defines for microphone detection levels · ffae24fe
      由 Charles Keepax 提交于 
      Improve readability by creating a define for each microphone detection
level.
Acked-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
      ffae24fe
    • A
      regulator: as3722: detect SD0 low-voltage mode · 762a8ee8
      由 Andrew Bresticker 提交于 
      SD0 may operate in low-voltage mode, with a minimum of 0.41V
and a maximum of 1.5V.  This is indicated by bit 4 of FUSE7.
Signed-off-by: NAndrew Bresticker <abrestic@chromium.org>
Signed-off-by: NVince Hsu <vinceh@nvidia.com>
broonie.e6264@m.evernote.com
Signed-off-by: NMark Brown <broonie@linaro.org>
      762a8ee8
  17. 30 12月, 2013 1 次提交
  19. 21 12月, 2013 1 次提交
  21. 19 12月, 2013 2 次提交
  23. 18 12月, 2013 1 次提交
  25. 13 12月, 2013 1 次提交
  27. 12 12月, 2013 1 次提交
  29. 09 12月, 2013 1 次提交
  31. 21 11月, 2013 1 次提交
  33. 20 11月, 2013 1 次提交
  35. 13 11月, 2013 1 次提交
  37. 11 11月, 2013 1 次提交
    • G
      mfd: Stop setting refcounting pointers in original mfd_cell arrays · 03e361b2
      由 Geert Uytterhoeven 提交于 
      Commit 1e29af62 ("mfd: Add refcounting
support to mfd_cells") had to drop the "const" keyword on the "cell"
parameter of mfd_add_devices(), as it added the refcounting pointers
to the objects of the passed mfd_cell array itself.

However, the mfd core code operates on copies of the mfd_cell objects,
so there's no need to modify the originally passed objects.

Hence, move the setting of the refcounting pointers from mfd_add_devices()
to mfd_platform_add_cell(), where the copy of the mfd_cell objects is made.
mfd_clone_cell() can just pass (a copy of) the original usage_count
pointer.

This allows to make the "cell" parameter of mfd_add_devices() "const"
again, and avoids future race conditions when registering multiple
instances of the same device in parallel.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
      03e361b2
  39. 23 10月, 2013 1 次提交