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linux/Documentation/devicetree/bindings/i2c/i2c-designware.txt

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i2c-designware: add OF binding support Add of_match_table and DT style i2c registration to designware i2c driver. Refactored for pci/plat split by Dirk Brandewie. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
2011-11-09 04:43:47 +08:00
* Synopsys DesignWare I2C
Required properties :
- compatible : should be "snps,designware-i2c"
- reg : Offset and length of the register set for the device
- interrupts : <IRQ> where IRQ is the interrupt number.
Recommended properties :
- clock-frequency : desired I2C bus clock frequency in Hz.
i2c-designware: make SDA hold time configurable This patch makes the SDA hold time configurable through device tree. Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com> Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-26 16:55:06 +08:00
Optional properties :
- i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds.
This option is only supported in hardware blocks version 1.11a or newer.
i2c: designware: Fix falling time bindings doc In (6468276 i2c: designware: make SCL and SDA falling time configurable) new device tree properties were added for setting the falling time of SDA and SCL. The device tree bindings doc had a typo in it: it forgot the "-ns" suffix for both properies in the prose of the bindings. I assume this is a typo because: * The source code includes the "-ns" * The example in the bindings includes the "-ns". Fix the typo. Signed-off-by: Doug Anderson <dianders@chromium.org> Fixes: 6468276b2206 ("i2c: designware: make SCL and SDA falling time configurable") Acked-by: Romain Baeriswyl <romain.baeriswyl@alitech.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2014-12-06 02:49:39 +08:00
- i2c-scl-falling-time-ns : should contain the SCL falling time in nanoseconds.
i2c: designware: make SCL and SDA falling time configurable This patch allows to set independantly SCL and SDA falling times. The tLOW period is computed by taking into account the SCL falling time. The tHIGH period is computed by taking into account the SDA falling time. For instance in case the margin on tLOW is considered too small, it can be increased by increasing the SCL falling time which is by default set at 300ns. The same applies for tHIGH period with the help of SDA falling time. Signed-off-by: Romain Baeriswyl <romainba@abilis.com> Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com> Acked-by: Shinya Kuribayashi <skuribay@pobox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-21 00:43:43 +08:00
This value which is by default 300ns is used to compute the tLOW period.
i2c: designware: Fix falling time bindings doc In (6468276 i2c: designware: make SCL and SDA falling time configurable) new device tree properties were added for setting the falling time of SDA and SCL. The device tree bindings doc had a typo in it: it forgot the "-ns" suffix for both properies in the prose of the bindings. I assume this is a typo because: * The source code includes the "-ns" * The example in the bindings includes the "-ns". Fix the typo. Signed-off-by: Doug Anderson <dianders@chromium.org> Fixes: 6468276b2206 ("i2c: designware: make SCL and SDA falling time configurable") Acked-by: Romain Baeriswyl <romain.baeriswyl@alitech.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2014-12-06 02:49:39 +08:00
- i2c-sda-falling-time-ns : should contain the SDA falling time in nanoseconds.
i2c: designware: make SCL and SDA falling time configurable This patch allows to set independantly SCL and SDA falling times. The tLOW period is computed by taking into account the SCL falling time. The tHIGH period is computed by taking into account the SDA falling time. For instance in case the margin on tLOW is considered too small, it can be increased by increasing the SCL falling time which is by default set at 300ns. The same applies for tHIGH period with the help of SDA falling time. Signed-off-by: Romain Baeriswyl <romainba@abilis.com> Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com> Acked-by: Shinya Kuribayashi <skuribay@pobox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-21 00:43:43 +08:00
This value which is by default 300ns is used to compute the tHIGH period.
i2c-designware: add OF binding support Add of_match_table and DT style i2c registration to designware i2c driver. Refactored for pci/plat split by Dirk Brandewie. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
2011-11-09 04:43:47 +08:00
Example :
i2c@f0000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "snps,designware-i2c";
reg = <0xf0000 0x1000>;
interrupts = <11>;
clock-frequency = <400000>;
};
i2c-designware: make SDA hold time configurable This patch makes the SDA hold time configurable through device tree. Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com> Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-26 16:55:06 +08:00
i2c@1120000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "snps,designware-i2c";
reg = <0x1120000 0x1000>;
interrupt-parent = <&ictl>;
interrupts = <12 1>;
clock-frequency = <400000>;
i2c-sda-hold-time-ns = <300>;
i2c: designware: make SCL and SDA falling time configurable This patch allows to set independantly SCL and SDA falling times. The tLOW period is computed by taking into account the SCL falling time. The tHIGH period is computed by taking into account the SDA falling time. For instance in case the margin on tLOW is considered too small, it can be increased by increasing the SCL falling time which is by default set at 300ns. The same applies for tHIGH period with the help of SDA falling time. Signed-off-by: Romain Baeriswyl <romainba@abilis.com> Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com> Acked-by: Shinya Kuribayashi <skuribay@pobox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-21 00:43:43 +08:00
i2c-sda-falling-time-ns = <300>;
i2c-scl-falling-time-ns = <300>;
i2c-designware: make SDA hold time configurable This patch makes the SDA hold time configurable through device tree. Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com> Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-26 16:55:06 +08:00
};