drivers/reset/reset-zynqmp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2018 Xilinx, Inc.
   4  *
   5  */
   6
   7 #include <linux/err.h>
   8 #include <linux/of.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/reset-controller.h>
  11 #include <linux/firmware/xlnx-zynqmp.h>
  12
  13 #define ZYNQMP_NR_RESETS (ZYNQMP_PM_RESET_END - ZYNQMP_PM_RESET_START)
  14 #define ZYNQMP_RESET_ID ZYNQMP_PM_RESET_START
  15
  16 struct zynqmp_reset_data {
  17         struct reset_controller_dev rcdev;
  18         const struct zynqmp_eemi_ops *eemi_ops;
  19 };
  20
  21 static inline struct zynqmp_reset_data *
  22 to_zynqmp_reset_data(struct reset_controller_dev *rcdev)
  23 {
  24         return container_of(rcdev, struct zynqmp_reset_data, rcdev);
  25 }
  26
  27 static int zynqmp_reset_assert(struct reset_controller_dev *rcdev,
  28                                unsigned long id)
  29 {
  30         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  31
  32         return priv->eemi_ops->reset_assert(ZYNQMP_RESET_ID + id,
  33                                             PM_RESET_ACTION_ASSERT);
  34 }
  35
  36 static int zynqmp_reset_deassert(struct reset_controller_dev *rcdev,
  37                                  unsigned long id)
  38 {
  39         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  40
  41         return priv->eemi_ops->reset_assert(ZYNQMP_RESET_ID + id,
  42                                             PM_RESET_ACTION_RELEASE);
  43 }
  44
  45 static int zynqmp_reset_status(struct reset_controller_dev *rcdev,
  46                                unsigned long id)
  47 {
  48         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  49         int val, err;
  50
  51         err = priv->eemi_ops->reset_get_status(ZYNQMP_RESET_ID + id, &val);
  52         if (err)
  53                 return err;
  54
  55         return val;
  56 }
  57
  58 static int zynqmp_reset_reset(struct reset_controller_dev *rcdev,
  59                               unsigned long id)
  60 {
  61         struct zynqmp_reset_data *priv = to_zynqmp_reset_data(rcdev);
  62
  63         return priv->eemi_ops->reset_assert(ZYNQMP_RESET_ID + id,
  64                                             PM_RESET_ACTION_PULSE);
  65 }
  66
  67 static struct reset_control_ops zynqmp_reset_ops = {
  68         .reset = zynqmp_reset_reset,
  69         .assert = zynqmp_reset_assert,
  70         .deassert = zynqmp_reset_deassert,
  71         .status = zynqmp_reset_status,
  72 };
  73
  74 static int zynqmp_reset_probe(struct platform_device *pdev)
  75 {
  76         struct zynqmp_reset_data *priv;
  77
  78         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  79         if (!priv)
  80                 return -ENOMEM;
  81
  82         platform_set_drvdata(pdev, priv);
  83
  84         priv->eemi_ops = zynqmp_pm_get_eemi_ops();
  85         if (!priv->eemi_ops)
  86                 return -ENXIO;
  87
  88         priv->rcdev.ops = &zynqmp_reset_ops;
  89         priv->rcdev.owner = THIS_MODULE;
  90         priv->rcdev.of_node = pdev->dev.of_node;
  91         priv->rcdev.nr_resets = ZYNQMP_NR_RESETS;
  92
  93         return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
  94 }
  95
  96 static const struct of_device_id zynqmp_reset_dt_ids[] = {
  97         { .compatible = "xlnx,zynqmp-reset", },
  98         { /* sentinel */ },
  99 };
 100
 101 static struct platform_driver zynqmp_reset_driver = {
 102         .probe  = zynqmp_reset_probe,
 103         .driver = {
 104                 .name           = KBUILD_MODNAME,
 105                 .of_match_table = zynqmp_reset_dt_ids,
 106         },
 107 };
 108
 109 static int __init zynqmp_reset_init(void)
 110 {
 111         return platform_driver_register(&zynqmp_reset_driver);
 112 }
 113
 114 arch_initcall(zynqmp_reset_init);