linux/drivers/reset/reset-uniphier-glue.c
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   1// SPDX-License-Identifier: GPL-2.0
   2//
   3// reset-uniphier-glue.c - Glue layer reset driver for UniPhier
   4// Copyright 2018 Socionext Inc.
   5// Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
   6
   7#include <linux/clk.h>
   8#include <linux/module.h>
   9#include <linux/of_device.h>
  10#include <linux/platform_device.h>
  11#include <linux/reset.h>
  12#include <linux/reset/reset-simple.h>
  13
  14#define MAX_CLKS        2
  15#define MAX_RSTS        2
  16
  17struct uniphier_glue_reset_soc_data {
  18        int nclks;
  19        const char * const *clock_names;
  20        int nrsts;
  21        const char * const *reset_names;
  22};
  23
  24struct uniphier_glue_reset_priv {
  25        struct clk_bulk_data clk[MAX_CLKS];
  26        struct reset_control *rst[MAX_RSTS];
  27        struct reset_simple_data rdata;
  28        const struct uniphier_glue_reset_soc_data *data;
  29};
  30
  31static int uniphier_glue_reset_probe(struct platform_device *pdev)
  32{
  33        struct device *dev = &pdev->dev;
  34        struct uniphier_glue_reset_priv *priv;
  35        struct resource *res;
  36        resource_size_t size;
  37        const char *name;
  38        int i, ret, nr;
  39
  40        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  41        if (!priv)
  42                return -ENOMEM;
  43
  44        priv->data = of_device_get_match_data(dev);
  45        if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
  46                    priv->data->nrsts > MAX_RSTS))
  47                return -EINVAL;
  48
  49        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  50        size = resource_size(res);
  51        priv->rdata.membase = devm_ioremap_resource(dev, res);
  52        if (IS_ERR(priv->rdata.membase))
  53                return PTR_ERR(priv->rdata.membase);
  54
  55        for (i = 0; i < priv->data->nclks; i++)
  56                priv->clk[i].id = priv->data->clock_names[i];
  57        ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
  58        if (ret)
  59                return ret;
  60
  61        for (i = 0; i < priv->data->nrsts; i++) {
  62                name = priv->data->reset_names[i];
  63                priv->rst[i] = devm_reset_control_get_shared(dev, name);
  64                if (IS_ERR(priv->rst[i]))
  65                        return PTR_ERR(priv->rst[i]);
  66        }
  67
  68        ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
  69        if (ret)
  70                return ret;
  71
  72        for (nr = 0; nr < priv->data->nrsts; nr++) {
  73                ret = reset_control_deassert(priv->rst[nr]);
  74                if (ret)
  75                        goto out_rst_assert;
  76        }
  77
  78        spin_lock_init(&priv->rdata.lock);
  79        priv->rdata.rcdev.owner = THIS_MODULE;
  80        priv->rdata.rcdev.nr_resets = size * BITS_PER_BYTE;
  81        priv->rdata.rcdev.ops = &reset_simple_ops;
  82        priv->rdata.rcdev.of_node = dev->of_node;
  83        priv->rdata.active_low = true;
  84
  85        platform_set_drvdata(pdev, priv);
  86
  87        ret = devm_reset_controller_register(dev, &priv->rdata.rcdev);
  88        if (ret)
  89                goto out_rst_assert;
  90
  91        return 0;
  92
  93out_rst_assert:
  94        while (nr--)
  95                reset_control_assert(priv->rst[nr]);
  96
  97        clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
  98
  99        return ret;
 100}
 101
 102static int uniphier_glue_reset_remove(struct platform_device *pdev)
 103{
 104        struct uniphier_glue_reset_priv *priv = platform_get_drvdata(pdev);
 105        int i;
 106
 107        for (i = 0; i < priv->data->nrsts; i++)
 108                reset_control_assert(priv->rst[i]);
 109
 110        clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
 111
 112        return 0;
 113}
 114
 115static const char * const uniphier_pro4_clock_reset_names[] = {
 116        "gio", "link",
 117};
 118
 119static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
 120        .nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
 121        .clock_names = uniphier_pro4_clock_reset_names,
 122        .nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
 123        .reset_names = uniphier_pro4_clock_reset_names,
 124};
 125
 126static const char * const uniphier_pxs2_clock_reset_names[] = {
 127        "link",
 128};
 129
 130static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
 131        .nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
 132        .clock_names = uniphier_pxs2_clock_reset_names,
 133        .nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
 134        .reset_names = uniphier_pxs2_clock_reset_names,
 135};
 136
 137static const struct of_device_id uniphier_glue_reset_match[] = {
 138        {
 139                .compatible = "socionext,uniphier-pro4-usb3-reset",
 140                .data = &uniphier_pro4_data,
 141        },
 142        {
 143                .compatible = "socionext,uniphier-pro5-usb3-reset",
 144                .data = &uniphier_pro4_data,
 145        },
 146        {
 147                .compatible = "socionext,uniphier-pxs2-usb3-reset",
 148                .data = &uniphier_pxs2_data,
 149        },
 150        {
 151                .compatible = "socionext,uniphier-ld20-usb3-reset",
 152                .data = &uniphier_pxs2_data,
 153        },
 154        {
 155                .compatible = "socionext,uniphier-pxs3-usb3-reset",
 156                .data = &uniphier_pxs2_data,
 157        },
 158        {
 159                .compatible = "socionext,uniphier-pro4-ahci-reset",
 160                .data = &uniphier_pro4_data,
 161        },
 162        {
 163                .compatible = "socionext,uniphier-pxs2-ahci-reset",
 164                .data = &uniphier_pxs2_data,
 165        },
 166        {
 167                .compatible = "socionext,uniphier-pxs3-ahci-reset",
 168                .data = &uniphier_pxs2_data,
 169        },
 170        { /* Sentinel */ }
 171};
 172MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
 173
 174static struct platform_driver uniphier_glue_reset_driver = {
 175        .probe = uniphier_glue_reset_probe,
 176        .remove = uniphier_glue_reset_remove,
 177        .driver = {
 178                .name = "uniphier-glue-reset",
 179                .of_match_table = uniphier_glue_reset_match,
 180        },
 181};
 182module_platform_driver(uniphier_glue_reset_driver);
 183
 184MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
 185MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
 186MODULE_LICENSE("GPL");
 187