Hi,
I want to note something here, if it's technical correct according the
CC2520 - Varka Bhadram needs to decide that.
On Sat, Mar 14, 2015 at 06:32:03PM -0400, Brad Campbell wrote:
> The TI CC2521 is an RF power amplifier that is designed to interface
> with the CC2520. Conveniently, it directly interfaces with the CC2520
> and does not require any pins to be connected to a
> microcontroller/processor. Adding a CC2591 increases the CC2520's range,
> which is useful for border router and other wall-powered applications.
>
> Using the CC2591 with the CC2520 requires configuring the CC2520 GPIOs
> that are connected to the CC2591 to correctly set the CC2591 into TX and
> RX modes. Further, TI recommends that the CC2520_TXPOWER and
> CC2520_AGCCTRL1 registers are set differently to maximize the CC2591's
> performance. These settings are covered in TI Application Note AN065.
>
> This patch adds an optional `amplified` field to the cc2520 entry in the
> device tree. If present and set to `1` the CC2520 will be configured to
> operate with a CC2591.
>
> The expected pin mapping is:
> CC2520 GPIO0 --> CC2591 EN
> CC2520 GPIO5 --> CC2591 PAEN
Signed-off-by is missing here. Create your patches with "fomat-patch -s"
or add a signed-off bt adding "-s" add your "git commit" commands.
> ---
> .../devicetree/bindings/net/ieee802154/cc2520.txt | 4 ++
> drivers/net/ieee802154/cc2520.c | 53 ++++++++++++++++++----
> include/linux/spi/cc2520.h | 1 +
> 3 files changed, 50 insertions(+), 8 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt b/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
> index 0071883..c6682f9 100644
> --- a/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
> +++ b/Documentation/devicetree/bindings/net/ieee802154/cc2520.txt
> @@ -13,11 +13,15 @@ Required properties:
> - cca-gpio: GPIO spec for the CCA pin
> - vreg-gpio: GPIO spec for the VREG pin
> - reset-gpio: GPIO spec for the RESET pin
> +Optional properties:
> + - amplified: set to 1 if the CC2520 is connected to a CC2591 amplifier
> +
Which Varka already mentioned this should be a bool.
> Example:
> cc2520@0 {
> compatible = "ti,cc2520";
> reg = <0>;
> spi-max-frequency = <4000000>;
> + amplified = <1>;
> pinctrl-names = "default";
> pinctrl-0 = <&cc2520_cape_pins>;
> fifo-gpio = <&gpio1 18 0>;
> diff --git a/drivers/net/ieee802154/cc2520.c b/drivers/net/ieee802154/cc2520.c
> index 181b349..37c7e00 100644
> --- a/drivers/net/ieee802154/cc2520.c
> +++ b/drivers/net/ieee802154/cc2520.c
> @@ -719,6 +719,7 @@ static int cc2520_hw_init(struct cc2520_private *priv)
> u8 status = 0, state = 0xff;
> int ret;
> int timeout = 100;
> + struct cc2520_platform_data *pdata = priv->spi->dev.platform_data;
>
Normal processing now is to have "read only" access on platform_data.
Look for commit:
aaa1c4d226e4cd730075d3dac99a6d599a0190c7 ("at86rf230: copy pdata to
driver allocated space")
for a similar issue and solution.
> ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
> if (ret)
> @@ -741,11 +742,46 @@ static int cc2520_hw_init(struct cc2520_private *priv)
>
> dev_vdbg(&priv->spi->dev, "oscillator brought up\n");
>
...
>
> + ret = of_property_read_s32(np, "amplified", &pdata->amplified);
> + if (ret < 0)
note: if you using "of_property_read_bool" then checking on failure isn't
required here.
I mentioned here because checking (ret < 0) is wrong for an optional
attribute. Correct would be if (ret < 0 && ret != -EINVAL). See [0].
"... -EINVAL if the property does not exist".
- Alex
[0] http://lxr.free-electrons.com/source/drivers/of/base.c#L1231
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