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_bulk_data rst[MAX_RSTS];
  27         struct reset_simple_data rdata;
  28         const struct uniphier_glue_reset_soc_data *data;
  29 };
  30
  31 static void uniphier_clk_disable(void *_priv)
  32 {
  33         struct uniphier_glue_reset_priv *priv = _priv;
  34
  35         clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
  36 }
  37
  38 static void uniphier_rst_assert(void *_priv)
  39 {
  40         struct uniphier_glue_reset_priv *priv = _priv;
  41
  42         reset_control_bulk_assert(priv->data->nrsts, priv->rst);
  43 }
  44
  45 static int uniphier_glue_reset_probe(struct platform_device *pdev)
  46 {
  47         struct device *dev = &pdev->dev;
  48         struct uniphier_glue_reset_priv *priv;
  49         struct resource *res;
  50         int i, ret;
  51
  52         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  53         if (!priv)
  54                 return -ENOMEM;
  55
  56         priv->data = of_device_get_match_data(dev);
  57         if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
  58                     priv->data->nrsts > MAX_RSTS))
  59                 return -EINVAL;
  60
  61         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  62         priv->rdata.membase = devm_ioremap_resource(dev, res);
  63         if (IS_ERR(priv->rdata.membase))
  64                 return PTR_ERR(priv->rdata.membase);
  65
  66         for (i = 0; i < priv->data->nclks; i++)
  67                 priv->clk[i].id = priv->data->clock_names[i];
  68         ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
  69         if (ret)
  70                 return ret;
  71
  72         for (i = 0; i < priv->data->nrsts; i++)
  73                 priv->rst[i].id = priv->data->reset_names[i];
  74         ret = devm_reset_control_bulk_get_shared(dev, priv->data->nrsts,
  75                                                  priv->rst);
  76         if (ret)
  77                 return ret;
  78
  79         ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
  80         if (ret)
  81                 return ret;
  82
  83         ret = devm_add_action_or_reset(dev, uniphier_clk_disable, priv);
  84         if (ret)
  85                 return ret;
  86
  87         ret = reset_control_bulk_deassert(priv->data->nrsts, priv->rst);
  88         if (ret)
  89                 return ret;
  90
  91         ret = devm_add_action_or_reset(dev, uniphier_rst_assert, priv);
  92         if (ret)
  93                 return ret;
  94
  95         spin_lock_init(&priv->rdata.lock);
  96         priv->rdata.rcdev.owner = THIS_MODULE;
  97         priv->rdata.rcdev.nr_resets = resource_size(res) * BITS_PER_BYTE;
  98         priv->rdata.rcdev.ops = &reset_simple_ops;
  99         priv->rdata.rcdev.of_node = dev->of_node;
 100         priv->rdata.active_low = true;
 101
 102         platform_set_drvdata(pdev, priv);
 103
 104         return devm_reset_controller_register(dev, &priv->rdata.rcdev);
 105 }
 106
 107 static const char * const uniphier_pro4_clock_reset_names[] = {
 108         "gio", "link",
 109 };
 110
 111 static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
 112         .nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
 113         .clock_names = uniphier_pro4_clock_reset_names,
 114         .nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
 115         .reset_names = uniphier_pro4_clock_reset_names,
 116 };
 117
 118 static const char * const uniphier_pxs2_clock_reset_names[] = {
 119         "link",
 120 };
 121
 122 static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
 123         .nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
 124         .clock_names = uniphier_pxs2_clock_reset_names,
 125         .nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
 126         .reset_names = uniphier_pxs2_clock_reset_names,
 127 };
 128
 129 static const struct of_device_id uniphier_glue_reset_match[] = {
 130         {
 131                 .compatible = "socionext,uniphier-pro4-usb3-reset",
 132                 .data = &uniphier_pro4_data,
 133         },
 134         {
 135                 .compatible = "socionext,uniphier-pro5-usb3-reset",
 136                 .data = &uniphier_pro4_data,
 137         },
 138         {
 139                 .compatible = "socionext,uniphier-pxs2-usb3-reset",
 140                 .data = &uniphier_pxs2_data,
 141         },
 142         {
 143                 .compatible = "socionext,uniphier-ld20-usb3-reset",
 144                 .data = &uniphier_pxs2_data,
 145         },
 146         {
 147                 .compatible = "socionext,uniphier-pxs3-usb3-reset",
 148                 .data = &uniphier_pxs2_data,
 149         },
 150         {
 151                 .compatible = "socionext,uniphier-nx1-usb3-reset",
 152                 .data = &uniphier_pxs2_data,
 153         },
 154         {
 155                 .compatible = "socionext,uniphier-pro4-ahci-reset",
 156                 .data = &uniphier_pro4_data,
 157         },
 158         {
 159                 .compatible = "socionext,uniphier-pxs2-ahci-reset",
 160                 .data = &uniphier_pxs2_data,
 161         },
 162         {
 163                 .compatible = "socionext,uniphier-pxs3-ahci-reset",
 164                 .data = &uniphier_pxs2_data,
 165         },
 166         { /* Sentinel */ }
 167 };
 168 MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
 169
 170 static struct platform_driver uniphier_glue_reset_driver = {
 171         .probe = uniphier_glue_reset_probe,
 172         .driver = {
 173                 .name = "uniphier-glue-reset",
 174                 .of_match_table = uniphier_glue_reset_match,
 175         },
 176 };
 177 module_platform_driver(uniphier_glue_reset_driver);
 178
 179 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
 180 MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
 181 MODULE_LICENSE("GPL");