[PATCH v5 0/9] i2c: add support for filters

From: Eugen.Hristev
Date: Wed Sep 11 2019 - 04:24:24 EST


From: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>

Hello,

This series adds support for analog and digital filters for i2c controllers

This series is based on the series:
[PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
and later
[PATCH v4 0/9] i2c: add support for filters
and enhanced to add the bindings for all controllers plus an extra bindings
for the width of the spikes in nanoseconds (digital filters) and cut-off
frequency (analog filters)

First, bindings are created for
'i2c-analog-filter'
'i2c-digital-filter'
'i2c-digital-filter-width-ns'
'i2c-analog-filter-cutoff-frequency'

The support is added in the i2c core to retrieve filter width/cutoff frequency
and add it to the timings structure.
Next, the at91 driver is enhanced for supporting digital filter, advanced
digital filter (with selectable spike width) and the analog filter.

Finally the device tree for two boards are modified to make use of the
new properties.

This series is the result of the comments on the ML in the direction
requested: to make the bindings globally available for i2c drivers.

Changes in v5:
- renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
is applicable only to digital filter
- created new binding i2c-digital-filter-width-ns for analog filters.

Changes in v4:
- renamed i2c-ana-filter to i2c-analog-filter
- renamed i2c-dig-filter to i2c-digital-filter

Changes in v3:
- made bindings global for i2c controllers and modified accordingly
- gave up PADFCDF bit because it's a lack in datasheet
- the computation on the width of the spike is based on periph clock as it
is done for hold time.

Changes in v2:
- added device tree bindings and support for enable-ana-filt and
enable-dig-filt
- added the new properties to the DT for sama5d4_xplained/sama5d2_xplained

Eugen Hristev (9):
dt-bindings: i2c: at91: add new compatible
dt-bindings: i2c: add bindings for i2c analog and digital filter
i2c: add support for filters optional properties
i2c: at91: add new platform support for sam9x60
i2c: at91: add support for digital filtering
i2c: at91: add support for advanced digital filtering
i2c: at91: add support for analog filtering
ARM: dts: at91: sama5d2_xplained: add analog and digital filter for
i2c
ARM: dts: at91: sama5d4_xplained: add digital filter for i2c

Documentation/devicetree/bindings/i2c/i2c-at91.txt | 3 +-
Documentation/devicetree/bindings/i2c/i2c.txt | 18 ++++++++
arch/arm/boot/dts/at91-sama5d2_xplained.dts | 6 +++
arch/arm/boot/dts/at91-sama5d4_xplained.dts | 1 +
drivers/i2c/busses/i2c-at91-core.c | 38 +++++++++++++++++
drivers/i2c/busses/i2c-at91-master.c | 49 ++++++++++++++++++++--
drivers/i2c/busses/i2c-at91.h | 13 ++++++
drivers/i2c/i2c-core-base.c | 6 +++
include/linux/i2c.h | 6 +++
9 files changed, 136 insertions(+), 4 deletions(-)

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2.7.4