drivers/reset/reset-uniphier-glue.c

   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
  17 struct 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
  24 struct 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
  31 static 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
  93 out_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
 102 static 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
 115 static const char * const uniphier_pro4_clock_reset_names[] = {
 116         "gio", "link",
 117 };
 118
 119 static 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
 126 static const char * const uniphier_pxs2_clock_reset_names[] = {
 127         "link",
 128 };
 129
 130 static 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
 137 static 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 };
 172 MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
 173
 174 static 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 };
 182 module_platform_driver(uniphier_glue_reset_driver);
 183
 184 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
 185 MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
 186 MODULE_LICENSE("GPL");