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 };
  19
  20 static inline struct zynqmp_reset_data *
  21 to_zynqmp_reset_data(struct reset_controller_dev *rcdev)
  22 {
  23         return container_of(rcdev, struct zynqmp_reset_data, rcdev);
  24 }
  25
  26 static int zynqmp_reset_assert(struct reset_controller_dev *rcdev,
  27                                unsigned long id)
  28 {
  29         return zynqmp_pm_reset_assert(ZYNQMP_RESET_ID + id,
  30                                       PM_RESET_ACTION_ASSERT);
  31 }
  32
  33 static int zynqmp_reset_deassert(struct reset_controller_dev *rcdev,
  34                                  unsigned long id)
  35 {
  36         return zynqmp_pm_reset_assert(ZYNQMP_RESET_ID + id,
  37                                       PM_RESET_ACTION_RELEASE);
  38 }
  39
  40 static int zynqmp_reset_status(struct reset_controller_dev *rcdev,
  41                                unsigned long id)
  42 {
  43         int val, err;
  44
  45         err = zynqmp_pm_reset_get_status(ZYNQMP_RESET_ID + id, &val);
  46         if (err)
  47                 return err;
  48
  49         return val;
  50 }
  51
  52 static int zynqmp_reset_reset(struct reset_controller_dev *rcdev,
  53                               unsigned long id)
  54 {
  55         return zynqmp_pm_reset_assert(ZYNQMP_RESET_ID + id,
  56                                       PM_RESET_ACTION_PULSE);
  57 }
  58
  59 static const struct reset_control_ops zynqmp_reset_ops = {
  60         .reset = zynqmp_reset_reset,
  61         .assert = zynqmp_reset_assert,
  62         .deassert = zynqmp_reset_deassert,
  63         .status = zynqmp_reset_status,
  64 };
  65
  66 static int zynqmp_reset_probe(struct platform_device *pdev)
  67 {
  68         struct zynqmp_reset_data *priv;
  69
  70         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  71         if (!priv)
  72                 return -ENOMEM;
  73
  74         platform_set_drvdata(pdev, priv);
  75
  76         priv->rcdev.ops = &zynqmp_reset_ops;
  77         priv->rcdev.owner = THIS_MODULE;
  78         priv->rcdev.of_node = pdev->dev.of_node;
  79         priv->rcdev.nr_resets = ZYNQMP_NR_RESETS;
  80
  81         return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
  82 }
  83
  84 static const struct of_device_id zynqmp_reset_dt_ids[] = {
  85         { .compatible = "xlnx,zynqmp-reset", },
  86         { /* sentinel */ },
  87 };
  88
  89 static struct platform_driver zynqmp_reset_driver = {
  90         .probe  = zynqmp_reset_probe,
  91         .driver = {
  92                 .name           = KBUILD_MODNAME,
  93                 .of_match_table = zynqmp_reset_dt_ids,
  94         },
  95 };
  96
  97 static int __init zynqmp_reset_init(void)
  98 {
  99         return platform_driver_register(&zynqmp_reset_driver);
 100 }
 101
 102 arch_initcall(zynqmp_reset_init);