2015-12-17 09:29:22 +00:00
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From 6d67bc40a1f5236fb00c503ab631819939efc01d Mon Sep 17 00:00:00 2001
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2015-10-26 09:01:05 +00:00
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From: Phil Elwell <phil@raspberrypi.org>
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Date: Mon, 12 Oct 2015 08:52:00 +0100
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2015-12-17 09:29:22 +00:00
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Subject: [PATCH 201/222] BCM270X_DT: Reduce default at86rf233 SPI frequency
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2015-10-26 09:01:05 +00:00
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The AT86RF233 has been found to be unreliable on a 7.5MHz SPI bus,
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so reduce the default frequency to 6MHz.
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See: https://github.com/raspberrypi/linux/issues/1151
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---
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arch/arm/boot/dts/overlays/README | 2 +-
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arch/arm/boot/dts/overlays/at86rf233-overlay.dts | 2 +-
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2 files changed, 2 insertions(+), 2 deletions(-)
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--- a/arch/arm/boot/dts/overlays/README
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+++ b/arch/arm/boot/dts/overlays/README
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@@ -178,7 +178,7 @@ Load: dtoverlay=at86rf233,<param>=<val
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Params: interrupt GPIO used for INT (default 23)
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reset GPIO used for Reset (default 24)
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sleep GPIO used for Sleep (default 25)
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- speed SPI bus speed in Hz (default 750000)
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+ speed SPI bus speed in Hz (default 6000000)
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trim Fine tuning of the internal capacitance
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arrays (0=+0pF, 15=+4.5pF, default 15)
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--- a/arch/arm/boot/dts/overlays/at86rf233-overlay.dts
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+++ b/arch/arm/boot/dts/overlays/at86rf233-overlay.dts
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@@ -25,7 +25,7 @@
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interrupts = <23 4>; /* active high */
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reset-gpio = <&gpio 24 1>;
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sleep-gpio = <&gpio 25 1>;
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- spi-max-frequency = <7500000>;
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+ spi-max-frequency = <6000000>;
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xtal-trim = /bits/ 8 <0xf>;
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};
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};
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