Re: [PATCH v9 0/2] PWM support for HiFive Unleashed

[Yash Shah]

On Tue, Mar 12, 2019 at 3:44 PM Andreas Schwab <schwab@xxxxxxx> wrote:
>
> On MÃr 12 2019, Yash Shah <yash.shah@xxxxxxxxxx> wrote:
>
> > This patch series adds a PWM driver and DT documentation
> > for HiFive Unleashed board. The patches are mostly based on
> > Wesley's patch.
>
> Heartbeat trigger still doesn't work for me.

You need to make sure the period setting is passed via the
conventional way in DT file.
Example:
pwmleds {
    compatible = "pwm-leds";
    heartbeat {
        pwms = <&L45 0 10000000 0>;
        max-brightness = <255>;
        linux,default-trigger = "heartbeat";
    };
};

I have tested on HiFive unleashed board. To modify DT file I performed
the following steps:

Use the open-source FSBL from:
https://github.com/sifive/freedom-u540-c000-bootloader

Modify the fsbl/ux00_fsbl.dts file and re-build the fsbl.bin

Steps for using fsbl.bin in HiFive Unleashed board:
https://github.com/sifive/freedom-u540-c000-bootloader/issues/9

>
> Andreas.
>
> --
> Andreas Schwab, SUSE Labs, schwab@xxxxxxx
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