Re: [PATCH V2] nvmem: add driver handling U-Boot environment variables

Hello Rafał,

On 03.05.22 18:56, Rafał Miłecki wrote:

From: Rafał Miłecki rafal@milecki.pl

U-Boot stores its setup as environment variables. It's a list of key-value pairs stored on flash device with a custom header.

This commit adds an NVMEM driver that:

1. Provides NVMEM access to environment vars binary data
2. Extracts variables as NVMEM cells

It can be used for:

1. Accessing env variables from user-space

Is this already possible? The only interface I know of is the /nvmem file in sysfs, but that one is not per cell, but per device.

• label = of_get_property(np->parent, "label", NULL);
• if (!label)

• label = np->parent->name;
  

• priv->mtd = get_mtd_device_nm(label);
• if (IS_ERR(priv->mtd)) {

• dev_err(dev, "Failed to find \"%s\" MTD device: %ld\n", label, PTR_ERR(priv->mtd));
  

• return PTR_ERR(priv->mtd);
  

• }

I am trying to make sense of this using the binding, but I can't. Do you have an example device tree fragment?

Cheers, Ahmad