Settings subsystem init fails (NVS backend)

RE: Settings subsystem init fails (NVS backend)

Gabriele — Tue, 11 Oct 2022 11:38:15 GMT

Hi Susheel,
the suggested change works fine.

RE: Settings subsystem init fails (NVS backend)

Susheel Nuguru — Mon, 10 Oct 2022 05:34:19 GMT

OK, I overlooked at the problem, sorry it was my bad.

The function you have modified (usb_update_sn_string_descriptor) is called from usb_device_init which in turn is called in the early stage of device bootup as shown in the usb_device.c

SYS_INIT(usb_device_init, POST_KERNEL, CONFIG_APPLICATION_INIT_PRIORITY);

This is initialized with the SYS_INIT POST_KERNEL level, and I do not think that the device tree macros are available at this level.

So now use the original code you posted (not using work queues) and try to change the usb_device.c last line to below to use APPLICATION level initialization.

SYS_INIT(usb_device_init, APPLICATION, CONFIG_APPLICATION_INIT_PRIORITY);

RE: Settings subsystem init fails (NVS backend)

Gabriele — Thu, 06 Oct 2022 11:41:40 GMT

Hi Susheel,
this is the exemplified code

static uint8_t sn[sizeof(CONFIG_USB_DEVICE_SN) + 1];
static uint32_t val = 0;
static struct k_work_delayable pending_work;
static void mywork(struct k_work *work)
{
    if (IS_ENABLED(CONFIG_SETTINGS)) {
        ...
        val = 123456789;
    }
}

uint8_t *usb_update_sn_string_descriptor(void)
{
    k_work_init_delayable(&pending_work, mywork);
    k_work_schedule(&pending_work, K_MSEC(3000));

    snprintk(sn, sizeof(sn), "%u", val);
    return sn;
}

Actually mywork() execution happens 3 s after usb_update_sn_string_descriptor().
The problem is that usb_update_sn_string_descriptor() will not return the desired (val) value set by mywork().

How to solve this ?

RE: Settings subsystem init fails (NVS backend)

Susheel Nuguru — Tue, 04 Oct 2022 10:57:47 GMT

yes, that is what I was thinking. to schedule a work item in your work queue and process if (IS_ENABLED(CONFIG_SETTINGS)) in that. Try it out to see if your device tree macro resolves to non NULL pointers.

RE: Settings subsystem init fails (NVS backend)

Gabriele — Mon, 03 Oct 2022 16:18:00 GMT

Hi Susheel,

do you mean

static struct k_work_delayable pending_work;
static void mywork(struct k_work *work)
{
//do something
}

If yes, can you please help me to figure out where the

k_work_schedule(&pending_work, mywork, K_MSEC(3000));

has to be called ?

RE: Settings subsystem init fails (NVS backend)

Susheel Nuguru — Fri, 30 Sep 2022 10:37:01 GMT

Hi,

I think usb_update_sn_string_descriptor is being called in the very early stage of kernel boot and hence that part of the device binding part is not ready yet?

maybe you can create a work_queue item to push the execution of the whole if statement

	if (IS_ENABLED(CONFIG_SETT

onto a lower priority context (work_queue).