LXR linux/drivers/nvmem/brcm

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2021 Rafał Miłecki <rafal@milecki.pl>
   4 */
   5
   6#include <linux/io.h>
   7#include <linux/mod_devicetable.h>
   8#include <linux/module.h>
   9#include <linux/nvmem-provider.h>
  10#include <linux/platform_device.h>
  11
  12struct brcm_nvram {
  13        struct device *dev;
  14        void __iomem *base;
  15};
  16
  17static int brcm_nvram_read(void *context, unsigned int offset, void *val,
  18                           size_t bytes)
  19{
  20        struct brcm_nvram *priv = context;
  21        u8 *dst = val;
  22
  23        while (bytes--)
  24                *dst++ = readb(priv->base + offset++);
  25
  26        return 0;
  27}
  28
  29static int brcm_nvram_probe(struct platform_device *pdev)
  30{
  31        struct nvmem_config config = {
  32                .name = "brcm-nvram",
  33                .reg_read = brcm_nvram_read,
  34        };
  35        struct device *dev = &pdev->dev;
  36        struct resource *res;
  37        struct brcm_nvram *priv;
  38
  39        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  40        if (!priv)
  41                return -ENOMEM;
  42        priv->dev = dev;
  43
  44        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  45        priv->base = devm_ioremap_resource(dev, res);
  46        if (IS_ERR(priv->base))
  47                return PTR_ERR(priv->base);
  48
  49        config.dev = dev;
  50        config.priv = priv;
  51        config.size = resource_size(res);
  52
  53        return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &config));
  54}
  55
  56static const struct of_device_id brcm_nvram_of_match_table[] = {
  57        { .compatible = "brcm,nvram", },
  58        {},
  59};
  60
  61static struct platform_driver brcm_nvram_driver = {
  62        .probe = brcm_nvram_probe,
  63        .driver = {
  64                .name = "brcm_nvram",
  65                .of_match_table = brcm_nvram_of_match_table,
  66        },
  67};
  68
  69static int __init brcm_nvram_init(void)
  70{
  71        return platform_driver_register(&brcm_nvram_driver);
  72}
  73
  74subsys_initcall_sync(brcm_nvram_init);
  75
  76MODULE_AUTHOR("Rafał Miłecki");
  77MODULE_LICENSE("GPL");
  78MODULE_DEVICE_TABLE(of, brcm_nvram_of_match_table);
  79