LXR linux/drivers/nvmem/qfprom.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
   4 */
   5
   6#include <linux/device.h>
   7#include <linux/module.h>
   8#include <linux/mod_devicetable.h>
   9#include <linux/io.h>
  10#include <linux/nvmem-provider.h>
  11#include <linux/platform_device.h>
  12
  13struct qfprom_priv {
  14        void __iomem *base;
  15};
  16
  17static int qfprom_reg_read(void *context,
  18                        unsigned int reg, void *_val, size_t bytes)
  19{
  20        struct qfprom_priv *priv = context;
  21        u8 *val = _val;
  22        int i = 0, words = bytes;
  23
  24        while (words--)
  25                *val++ = readb(priv->base + reg + i++);
  26
  27        return 0;
  28}
  29
  30static int qfprom_reg_write(void *context,
  31                         unsigned int reg, void *_val, size_t bytes)
  32{
  33        struct qfprom_priv *priv = context;
  34        u8 *val = _val;
  35        int i = 0, words = bytes;
  36
  37        while (words--)
  38                writeb(*val++, priv->base + reg + i++);
  39
  40        return 0;
  41}
  42
  43static struct nvmem_config econfig = {
  44        .name = "qfprom",
  45        .stride = 1,
  46        .word_size = 1,
  47        .reg_read = qfprom_reg_read,
  48        .reg_write = qfprom_reg_write,
  49};
  50
  51static int qfprom_probe(struct platform_device *pdev)
  52{
  53        struct device *dev = &pdev->dev;
  54        struct resource *res;
  55        struct nvmem_device *nvmem;
  56        struct qfprom_priv *priv;
  57
  58        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  59        if (!priv)
  60                return -ENOMEM;
  61
  62        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  63        priv->base = devm_ioremap_resource(dev, res);
  64        if (IS_ERR(priv->base))
  65                return PTR_ERR(priv->base);
  66
  67        econfig.size = resource_size(res);
  68        econfig.dev = dev;
  69        econfig.priv = priv;
  70
  71        nvmem = devm_nvmem_register(dev, &econfig);
  72
  73        return PTR_ERR_OR_ZERO(nvmem);
  74}
  75
  76static const struct of_device_id qfprom_of_match[] = {
  77        { .compatible = "qcom,qfprom",},
  78        {/* sentinel */},
  79};
  80MODULE_DEVICE_TABLE(of, qfprom_of_match);
  81
  82static struct platform_driver qfprom_driver = {
  83        .probe = qfprom_probe,
  84        .driver = {
  85                .name = "qcom,qfprom",
  86                .of_match_table = qfprom_of_match,
  87        },
  88};
  89module_platform_driver(qfprom_driver);
  90MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>");
  91MODULE_DESCRIPTION("Qualcomm QFPROM driver");
  92MODULE_LICENSE("GPL v2");
  93