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About linux : How-to-register-LED-for-MMC-device

Question Detail

Our goal is to flash led when sd card is reading or writing.

In mmc driver, I can know there is a function call led_trigger_event(). It looks like to control LED when MMC is do something.

ex: led_trigger_event(host->led, LED_OFF);

However, in our DTS, I didn’t see any LED setting for mmc1.
Is there anyone can give some info how to register LED for mmc1?

sdhci1: [email protected] {
    compatible = "ti,am654-sdhci-5.1";
    reg = <0x0 0x4fa0000 0x0 0x260>, <0x0 0x4fb0000 0x0 0x134>;
    power-domains = <&k3_pds 48 TI_SCI_PD_EXCLUSIVE>;
    clocks = <&k3_clks 48 0>, <&k3_clks 48 1>;
    clock-names = "clk_ahb", "clk_xin";
    interrupts = <GIC_SPI 137 IRQ_TYPE_LEVEL_HIGH>;
    ti,otap-del-sel-legacy = <0x0>;
    ti,otap-del-sel-mmc-hs = <0x0>;
    ti,otap-del-sel-sd-hs = <0x0>;
    ti,otap-del-sel-sdr12 = <0x0>;
    ti,otap-del-sel-sdr25 = <0x0>;
    ti,otap-del-sel-sdr50 = <0x8>;
    ti,otap-del-sel-sdr104 = <0x7>;
    ti,otap-del-sel-ddr50 = <0x4>;
    ti,otap-del-sel-ddr52 = <0x4>;
    ti,otap-del-sel-hs200 = <0x7>;
    ti,trm-icp = <0x8>;
    no-1-8-v;
    dma-coherent;
};

Btw, I also tried to use echo mmc1 > /sys/class/leds/xxx/trigger, but the LED frequency is too high to see it’s blinking.
That’s why I need to find another way to do this.

Question Answer

No answer for now.

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