Commit 1696f364 authored Jul 25, 2013 by Oleksandr Kozaruk Committed by Jonathan Cameron Aug 17, 2013

iio: twl6030-gpadc: TWL6030, TWL6032 GPADC driver



The GPADC is general purpose ADC found on TWL6030, and TWL6032 PMIC,
known also as Phoenix and PhoenixLite.

The TWL6030 and TWL6032 have GPADC with 17 and 19 channels
respectively. Some channels have current source and are used for
measuring voltage drop on resistive load for detecting battery ID
resistance, or measuring voltage drop on NTC resistors for external
temperature measurements. Some channels measure voltage, (i.e. battery
voltage), and have voltage dividers, thus, capable to scale voltage.
Some channels are dedicated for measuring die temperature.

Some channels are calibrated in 2 points, having offsets from ideal
values kept in trim registers. This is used to correct measurements.

The differences between GPADC in TWL6030 and TWL6032:
- 10 bit vs 12 bit ADC;
- 17 vs 19 channels;
- channels have different purpose(i.e. battery voltage
  channel 8 vs channel 18);
- trim values are interpreted differently.

Based on the driver patched from Balaji TK, Graeme Gregory, Ambresh K,
Girish S Ghongdemath.

Signed-off-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Graeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: Oleksandr Kozaruk <oleksandr.kozaruk@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

parent 1eb70a97

drivers/iio/adc/Kconfig

+14 −0

Original line number	Diff line number	Diff line
		@@ -171,6 +171,20 @@ config TI_AM335X_ADC
		Say yes here to build support for Texas Instruments ADC
		driver which is also a MFD client.

		config TWL6030_GPADC
		tristate "TWL6030 GPADC (General Purpose A/D Converter) Support"
		depends on TWL4030_CORE
		default n
		help
		Say yes here if you want support for the TWL6030/TWL6032 General
		Purpose A/D Converter. This will add support for battery type
		detection, battery voltage and temperature measurement, die
		temperature measurement, system supply voltage, audio accessory,
		USB ID detection.

		This driver can also be built as a module. If so, the module will be
		called twl6030-gpadc.

		config VIPERBOARD_ADC
		tristate "Viperboard ADC support"
		depends on MFD_VIPERBOARD && USB

drivers/iio/adc/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -19,4 +19,5 @@ obj-$(CONFIG_MCP320X) += mcp320x.o
		obj-$(CONFIG_NAU7802) += nau7802.o
		obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
		obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o
		obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o
		obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o

drivers/iio/adc/twl6030-gpadc.c

0 → 100644

+1029 −0

File added.

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