LXR linux/drivers/nvmem/qfprom.c

   1/*
   2 * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 and
   6 * only version 2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 * GNU General Public License for more details.
  12 */
  13
  14#include <linux/device.h>
  15#include <linux/module.h>
  16#include <linux/io.h>
  17#include <linux/nvmem-provider.h>
  18#include <linux/platform_device.h>
  19
  20static int qfprom_reg_read(void *context,
  21                        unsigned int reg, void *_val, size_t bytes)
  22{
  23        void __iomem *base = context;
  24        u32 *val = _val;
  25        int i = 0, words = bytes / 4;
  26
  27        while (words--)
  28                *val++ = readl(base + reg + (i++ * 4));
  29
  30        return 0;
  31}
  32
  33static int qfprom_reg_write(void *context,
  34                         unsigned int reg, void *_val, size_t bytes)
  35{
  36        void __iomem *base = context;
  37        u32 *val = _val;
  38        int i = 0, words = bytes / 4;
  39
  40        while (words--)
  41                writel(*val++, base + reg + (i++ * 4));
  42
  43        return 0;
  44}
  45
  46static int qfprom_remove(struct platform_device *pdev)
  47{
  48        struct nvmem_device *nvmem = platform_get_drvdata(pdev);
  49
  50        return nvmem_unregister(nvmem);
  51}
  52
  53static struct nvmem_config econfig = {
  54        .name = "qfprom",
  55        .owner = THIS_MODULE,
  56        .stride = 4,
  57        .word_size = 1,
  58        .reg_read = qfprom_reg_read,
  59        .reg_write = qfprom_reg_write,
  60};
  61
  62static int qfprom_probe(struct platform_device *pdev)
  63{
  64        struct device *dev = &pdev->dev;
  65        struct resource *res;
  66        struct nvmem_device *nvmem;
  67        void __iomem *base;
  68
  69        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  70        base = devm_ioremap_resource(dev, res);
  71        if (IS_ERR(base))
  72                return PTR_ERR(base);
  73
  74        econfig.size = resource_size(res);
  75        econfig.dev = dev;
  76        econfig.priv = base;
  77
  78        nvmem = nvmem_register(&econfig);
  79        if (IS_ERR(nvmem))
  80                return PTR_ERR(nvmem);
  81
  82        platform_set_drvdata(pdev, nvmem);
  83
  84        return 0;
  85}
  86
  87static const struct of_device_id qfprom_of_match[] = {
  88        { .compatible = "qcom,qfprom",},
  89        {/* sentinel */},
  90};
  91MODULE_DEVICE_TABLE(of, qfprom_of_match);
  92
  93static struct platform_driver qfprom_driver = {
  94        .probe = qfprom_probe,
  95        .remove = qfprom_remove,
  96        .driver = {
  97                .name = "qcom,qfprom",
  98                .of_match_table = qfprom_of_match,
  99        },
 100};
 101module_platform_driver(qfprom_driver);
 102MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>");
 103MODULE_DESCRIPTION("Qualcomm QFPROM driver");
 104MODULE_LICENSE("GPL v2");
 105