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BCM270X_DT: Set spidev spi-max-frequency to 125MHz
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The BCM2835 SPI controllers have a maximum bus clock of half the system
clock speed, so with the 250MHz system clock found on Raspberry Pis
you get a theoretical maximum bus speed of 125MHz. Note that this
speed is unlikely to be reliable, and the maximum usable bus spee will
depend on both the attached device and the wiring.

See: raspberrypi#2165
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
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Phil Elwell committed Nov 19, 2017
1 parent 30e7ff6 commit 6433ca8
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Showing 13 changed files with 26 additions and 26 deletions.
4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2708-rpi-0-w.dts
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Expand Up @@ -101,15 +101,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2708-rpi-b-plus.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -53,15 +53,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2708-rpi-b.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -53,15 +53,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2708-rpi-cm.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -52,15 +52,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2709-rpi-2-b.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -53,15 +53,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2710-rpi-3-b.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -125,15 +125,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/bcm2710-rpi-cm3.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -70,15 +70,15 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};

spidev1: spidev@1{
compatible = "spidev";
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
};
};

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2 changes: 1 addition & 1 deletion arch/arm/boot/dts/overlays/spi1-1cs-overlay.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};
};
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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/overlays/spi1-2cs-overlay.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};

Expand All @@ -45,7 +45,7 @@
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};
};
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6 changes: 3 additions & 3 deletions arch/arm/boot/dts/overlays/spi1-3cs-overlay.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};

Expand All @@ -45,7 +45,7 @@
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};

Expand All @@ -54,7 +54,7 @@
reg = <2>; /* CE2 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};
};
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2 changes: 1 addition & 1 deletion arch/arm/boot/dts/overlays/spi2-1cs-overlay.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};
};
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4 changes: 2 additions & 2 deletions arch/arm/boot/dts/overlays/spi2-2cs-overlay.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};

Expand All @@ -45,7 +45,7 @@
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};
};
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6 changes: 3 additions & 3 deletions arch/arm/boot/dts/overlays/spi2-3cs-overlay.dts
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Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@
reg = <0>; /* CE0 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};

Expand All @@ -45,7 +45,7 @@
reg = <1>; /* CE1 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};

Expand All @@ -54,7 +54,7 @@
reg = <2>; /* CE2 */
#address-cells = <1>;
#size-cells = <0>;
spi-max-frequency = <500000>;
spi-max-frequency = <125000000>;
status = "okay";
};
};
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