LXR linux/drivers/nvmem/zynqmp

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2019 Xilinx, Inc.
   4 */
   5
   6#include <linux/module.h>
   7#include <linux/nvmem-provider.h>
   8#include <linux/of.h>
   9#include <linux/platform_device.h>
  10#include <linux/firmware/xlnx-zynqmp.h>
  11
  12#define SILICON_REVISION_MASK 0xF
  13
  14struct zynqmp_nvmem_data {
  15        struct device *dev;
  16        struct nvmem_device *nvmem;
  17};
  18
  19static const struct zynqmp_eemi_ops *eemi_ops;
  20
  21static int zynqmp_nvmem_read(void *context, unsigned int offset,
  22                             void *val, size_t bytes)
  23{
  24        int ret;
  25        int idcode, version;
  26        struct zynqmp_nvmem_data *priv = context;
  27
  28        if (!eemi_ops->get_chipid)
  29                return -ENXIO;
  30
  31        ret = eemi_ops->get_chipid(&idcode, &version);
  32        if (ret < 0)
  33                return ret;
  34
  35        dev_dbg(priv->dev, "Read chipid val %x %x\n", idcode, version);
  36        *(int *)val = version & SILICON_REVISION_MASK;
  37
  38        return 0;
  39}
  40
  41static struct nvmem_config econfig = {
  42        .name = "zynqmp-nvmem",
  43        .owner = THIS_MODULE,
  44        .word_size = 1,
  45        .size = 1,
  46        .read_only = true,
  47};
  48
  49static const struct of_device_id zynqmp_nvmem_match[] = {
  50        { .compatible = "xlnx,zynqmp-nvmem-fw", },
  51        { /* sentinel */ },
  52};
  53MODULE_DEVICE_TABLE(of, zynqmp_nvmem_match);
  54
  55static int zynqmp_nvmem_probe(struct platform_device *pdev)
  56{
  57        struct device *dev = &pdev->dev;
  58        struct zynqmp_nvmem_data *priv;
  59
  60        priv = devm_kzalloc(dev, sizeof(struct zynqmp_nvmem_data), GFP_KERNEL);
  61        if (!priv)
  62                return -ENOMEM;
  63
  64        eemi_ops = zynqmp_pm_get_eemi_ops();
  65        if (IS_ERR(eemi_ops))
  66                return PTR_ERR(eemi_ops);
  67
  68        priv->dev = dev;
  69        econfig.dev = dev;
  70        econfig.reg_read = zynqmp_nvmem_read;
  71        econfig.priv = priv;
  72
  73        priv->nvmem = devm_nvmem_register(dev, &econfig);
  74
  75        return PTR_ERR_OR_ZERO(priv->nvmem);
  76}
  77
  78static struct platform_driver zynqmp_nvmem_driver = {
  79        .probe = zynqmp_nvmem_probe,
  80        .driver = {
  81                .name = "zynqmp-nvmem",
  82                .of_match_table = zynqmp_nvmem_match,
  83        },
  84};
  85
  86module_platform_driver(zynqmp_nvmem_driver);
  87
  88MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>, Nava kishore Manne <navam@xilinx.com>");
  89MODULE_DESCRIPTION("ZynqMP NVMEM driver");
  90MODULE_LICENSE("GPL");
  91