The SPMI VADC and the earlier XOADC share a subset of
common code, so to be able to use the same code in both
drivers, we break out a separate file with the common code,
prefix exported functions that are no longer static with
qcom_* and bake an object qcom-spmi-vadc.o that contains both
files: qcom-vadc-common.o and qcom-spmi-vadc-core.o.

As we need to follow the procedure for making a kernel module
or compiled in object from several files, but still want to
produce the same module name, rename the qcom-spmi-vadc.c
file to qcom-spmi-vadc-core.c so we can bake the two objects
into qcom-spmi-vadc.o

Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arm-msm@vger.kernel.org
Cc: Ivan T. Ivanov <iivanov.xz@gmail.com>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Rama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Another one of these that we missed previously which prevents test builds
of this driver on 32 bit platforms as it gives an undefined __divdi3 warning.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

It is meant to be long and is only added to an s64.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Cc: Rama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

A simple do_div call works here as all the signed 64 bit is
actually small and unsigned at this point, and the numerator is
u32.

Introduce a temporary u64 variable to avoid type comparison warnings
on some architectures.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Cc: Rama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Several ADC channels are supported in PMIC which can be used to
measure voltage, temperature, current etc. Different scaling can be
applied on the obtained voltage to report in physical units. Scaling
functionality can be different per channel. Add scaling support per
channel. Every channel present in adc has an unique conversion formula
for obtained voltage. Add support to report in Raw as well as in
processed format. Scaling is applied when processed read is requested
and is not applied when a Raw read is requested.
Signed-off-by: NRama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Several channels are supported in ADC of PMIC which can be used to
measure voltage, temperature, current etc., Hardware provides
readings for all channels in adc code. That adc code needs to be
converted to voltage. Logic for conversion of adc code to voltage
is common for all ADC channels(voltage, temperature, current
.,etc). Implement separate function for generic conversion logic.
Signed-off-by: NRama Krishna Phani A <rphani@codeaurora.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

for_each_available_child_of_node performs an of_node_get on each iteration,
so a break out of the loop requires an of_node_put.

A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):

// <smpl>
@@
expression root,e;
local idexpression child;
@@

 for_each_available_child_of_node(root, child) {
   ... when != of_node_put(child)
       when != e = child
(
   return child;
|
+  of_node_put(child);
?  return ...;
)
   ...
 }
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

With 'dx' equal to 0.625V and 15 bit ADC, calculations overflow
when difference against GND is ~20% of the ADC range. Fix this.
Signed-off-by: NIvan T. Ivanov <ivan.ivanov@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The voltage ADC is peripheral of Qualcomm SPMI PMIC chips. It has
15bits resolution and register space inside PMIC accessible across
SPMI bus.

The vadc driver registers itself through IIO interface.
Signed-off-by: NStanimir Varbanov <svarbanov@mm-sol.com>
Signed-off-by: NIvan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>