drivers/nvmem/layerscape-sfp.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Layerscape SFP driver
   4  *
   5  * Copyright (c) 2022 Michael Walle <michael@walle.cc>
   6  *
   7  */
   8
   9 #include <linux/device.h>
  10 #include <linux/io.h>
  11 #include <linux/mod_devicetable.h>
  12 #include <linux/module.h>
  13 #include <linux/nvmem-provider.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/property.h>
  16
  17 #define LAYERSCAPE_SFP_OTP_OFFSET       0x0200
  18
  19 struct layerscape_sfp_priv {
  20         void __iomem *base;
  21 };
  22
  23 struct layerscape_sfp_data {
  24         int size;
  25 };
  26
  27 static int layerscape_sfp_read(void *context, unsigned int offset, void *val,
  28                                size_t bytes)
  29 {
  30         struct layerscape_sfp_priv *priv = context;
  31
  32         memcpy_fromio(val, priv->base + LAYERSCAPE_SFP_OTP_OFFSET + offset,
  33                       bytes);
  34
  35         return 0;
  36 }
  37
  38 static struct nvmem_config layerscape_sfp_nvmem_config = {
  39         .name = "fsl-sfp",
  40         .reg_read = layerscape_sfp_read,
  41 };
  42
  43 static int layerscape_sfp_probe(struct platform_device *pdev)
  44 {
  45         const struct layerscape_sfp_data *data;
  46         struct layerscape_sfp_priv *priv;
  47         struct nvmem_device *nvmem;
  48
  49         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  50         if (!priv)
  51                 return -ENOMEM;
  52
  53         priv->base = devm_platform_ioremap_resource(pdev, 0);
  54         if (IS_ERR(priv->base))
  55                 return PTR_ERR(priv->base);
  56
  57         data = device_get_match_data(&pdev->dev);
  58
  59         layerscape_sfp_nvmem_config.size = data->size;
  60         layerscape_sfp_nvmem_config.dev = &pdev->dev;
  61         layerscape_sfp_nvmem_config.priv = priv;
  62
  63         nvmem = devm_nvmem_register(&pdev->dev, &layerscape_sfp_nvmem_config);
  64
  65         return PTR_ERR_OR_ZERO(nvmem);
  66 }
  67
  68 static const struct layerscape_sfp_data ls1028a_data = {
  69         .size = 0x88,
  70 };
  71
  72 static const struct of_device_id layerscape_sfp_dt_ids[] = {
  73         { .compatible = "fsl,ls1028a-sfp", .data = &ls1028a_data },
  74         {},
  75 };
  76 MODULE_DEVICE_TABLE(of, layerscape_sfp_dt_ids);
  77
  78 static struct platform_driver layerscape_sfp_driver = {
  79         .probe  = layerscape_sfp_probe,
  80         .driver = {
  81                 .name   = "layerscape_sfp",
  82                 .of_match_table = layerscape_sfp_dt_ids,
  83         },
  84 };
  85 module_platform_driver(layerscape_sfp_driver);
  86
  87 MODULE_AUTHOR("Michael Walle <michael@walle.cc>");
  88 MODULE_DESCRIPTION("Layerscape Security Fuse Processor driver");
  89 MODULE_LICENSE("GPL");