regulator: Introduce TI Adaptive Body Bias(ABB) on-chip LDO driver

Adaptive Body Biasing (ABB) modulates transistor bias voltages
dynamically in order to optimize switching speed versus leakage.

Texas Instruments' SmartReflex 2 technology provides support for this
power management technique with Forward Body Biasing (FBB) and Reverse
Body Biasing (RBB). These modulate the body voltage of transistor
cells or blocks dynamically to gain performance and reduce leakage.
TI's SmartReflex white paper[1] has further information for usage in
conjunction with other power management techniques.

The application of FBB/RBB technique is determined for each unique
device in some process nodes, whereas, they are mandated on other
process nodes.

In a nutshell, ABB technique is implemented on TI SoC as an on-chip
LDO which has ABB module controlling the bias voltage. However, the
voltage is unique per device. These vary per SoC family and the manner
in which these techniques are used may vary depending on the Operating
Performance Point (OPP) voltage targeted. For example:
OMAP3630/OMAP4430: certain OPPs mandate usage of FBB independent of
	devices.
OMAP4460/OMAP4470: certain OPPs mandate usage of FBB, while others may
	optionally use FBB or optimization with RBB.
OMAP5: ALL OPPs may optionally use ABB, and ABB biasing voltage is
	influenced by vset fused in s/w and requiring s/w override of
	default values.

Further, two generations of ABB module are used in various TI SoCs.
They have remained mostly register field compatible, however the
register offset had switched between versions.

We introduce ABB LDO support in the form of a regulator which is
controlled by voltages denoting the desired Operating Performance
Point which is targeted. However, since ABB transition is part of OPP
change sequence, the sequencing required to ensure sane operation
w.r.t OPP change is left to the controlling driver (example: cpufreq
SoC driver) using standard regulator operations.

The driver supports all ABB modes and ability to override ABB LDO vset
control efuse based ABB mode detection etc.

Current implementation is heavily influenced by the original patch
series [2][3] from Mike Turquette. However, the current implementation
supports only device tree based information.

[1] http://www.ti.com/pdfs/wtbu/smartreflex_whitepaper.pdf
[2] http://marc.info/?l=linux-omap&m=134931341818379&w=2
[3] http://marc.info/?l=linux-arm-kernel&m=134931402406853&w=2

[nm@ti.com: co-developer]
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Andrii.Tseglytskyi <andrii.tseglytskyi@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regulator: ti-abb: Fix off-by-one valid range checking for abb->current_info_idx

abb->current_info_idx is used as array subscript to access volt_table,
thus the valid value range should be 0 ... desc->n_voltages - 1.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regulator: Remove all platform_set_drvdata(pdev, NULL) in drivers

Since 0998d06310 "device-core: Ensure drvdata = NULL when no driver is bound",
this is done by driver core after device_release or on probe failure.
Thus we can remove all platform_set_drvdata(pdev, NULL) in drivers.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regulator: isl6271a: Use NULL instead of 0

init_data is a pointer. Use NULL instead of 0.

Silences the following sparse warning:
drivers/regulator/isl6271a-regulator.c:133:44:
warning: Using plain integer as NULL pointer

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regulator: Remove unnecessary include of linux/delay.h from regulator drivers

All the drivers that need delay for the regulator voltage output voltage to
stabilize after being enabled or after being set to a new value has been
converted to implement enable_time and set_voltage_time_sel callbacks.
Then regulator core will take care of the necessary delay.

This patch removes the unneeded include of linux/delay.h in regulator drivers.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Cc: Daniel Jeong <daniel.jeong@ti.com>
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: Chiwoong Byun <woong.byun@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regmap: Add support for discarding parts of the register cache

Allow drivers to discard parts of the register cache, for example if part
of the hardware has been reset.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regmap: Make regmap_check_range_table() a public API

Allow drivers to use an access table as part of their implementation.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regmap: rbtree: Factor out node allocation

In preparation for being slightly smarter about how we allocate memory
factor out the node allocation.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regmap: rbtree: Use range information to allocate nodes

If range information has been provided then when we allocate a rbnode
within a range allocate the entire range. The goal is to minimise the
number of reallocations done when combining or extending blocks. At
present only readability and yes_ranges are taken into account, this is
expected to cover most cases efficiently.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regmap: debugfs: Don't mark lockdep as broken due to debugfs write

A register write to hardware is reasonably unlikely to cause locking
dependency issues, the reason we're tainting is that unexpected changes
in the hardware configuration may confuse drivers.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi/pxa2xx: fix compile warning in pxa2xx_spi_acpi_get_pdata()

Commit cbfd6a21b6f (spi/pxa2xx: Convert to devm_ioremap_resource())
converted the driver to use devm_ioremap_resource(). However it causes
following warning to be emitted:

drivers/spi/spi-pxa2xx.c: In function ‘pxa2xx_spi_acpi_get_pdata’:
drivers/spi/spi-pxa2xx.c:1094:3: warning: return makes pointer from integer without a cast [enabled by default]

Fix this by returning NULL as it was done previously (error printing is
already done by devm_ioremap_resource()).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi/pxa2xx: convert to dma_request_slave_channel_compat()

Now that we have these nice DMA API helper functions we can take advantage
of those instead of open-coding the channel/request line extraction from
ACPI. Use the _compat version which still allows passing the
channel/request line from platform data.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi/pxa2xx: add Intel BayTrail ACPI ID

Intel BayTrail has one general purpose SPI controller that is compatible
with Intel Low Power Subsystem SPI. The controller is enumerated from ACPI
namespace with ACPI ID 80860F0E.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi: remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure, since commit 0998d0631001288a5974afc0b2a5f568bcdecb4d
(device-core: Ensure drvdata = NULL when no driver is bound).
Thus, it is not needed to manually clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi: bmc2835: use devm_ioremap_resource()

Replace a call to deprecated devm_request_and_ioremap by devm_ioremap_resource.

Found with coccicheck and this semantic patch:
 scripts/coccinelle/api/devm_request_and_ioremap.cocci.

Signed-off-by: Laurent Navet <laurent.navet@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi: spi-imx: Let device core handle pinctrl

Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.

So remove devm_pinctrl_get_select_default() from the driver.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi/omap2: Let device core handle pinctrl

Since commit ab78029 (drivers/pinctrl: grab default handles from device
core) we can rely on device core for handling pinctrl so remove
devm_pinctrl_get_select_default() from the driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
spi/sirf: Let device core handle pinctrl

Since commit ab78029 (drivers/pinctrl: grab default handles from device
core) we can rely on device core for handling pinctrl so remove
devm_pinctrl_get_select_default() from the driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Barry Song <baohua.song@csr.com>
spi: spi-mxs: Let device core handle pinctrl

Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.

So remove devm_pinctrl_get_select_default() from the driver.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
regmap: debugfs: Fix return from regmap_debugfs_get_dump_start

regmap_debugfs_get_dump_start should return the offset of the register
it should start reading from, However in the current code at one point
the code does not return correct register offset.

With this patch all the returns from this function takes reg_stride in
to consideration to return correct offset.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>