drivers/clk/meson/meson-aoclk.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Amlogic Meson-AXG Clock Controller Driver
   4  *
   5  * Copyright (c) 2016 BayLibre, SAS.
   6  * Author: Neil Armstrong <narmstrong@baylibre.com>
   7  *
   8  * Copyright (c) 2018 Amlogic, inc.
   9  * Author: Qiufang Dai <qiufang.dai@amlogic.com>
  10  * Author: Yixun Lan <yixun.lan@amlogic.com>
  11  */
  12
  13 #include <linux/platform_device.h>
  14 #include <linux/reset-controller.h>
  15 #include <linux/mfd/syscon.h>
  16 #include <linux/of.h>
  17 #include <linux/module.h>
  18
  19 #include <linux/slab.h>
  20 #include "meson-aoclk.h"
  21
  22 static int meson_aoclk_do_reset(struct reset_controller_dev *rcdev,
  23                                unsigned long id)
  24 {
  25         struct meson_aoclk_reset_controller *rstc =
  26                 container_of(rcdev, struct meson_aoclk_reset_controller, reset);
  27
  28         return regmap_write(rstc->regmap, rstc->data->reset_reg,
  29                             BIT(rstc->data->reset[id]));
  30 }
  31
  32 static const struct reset_control_ops meson_aoclk_reset_ops = {
  33         .reset = meson_aoclk_do_reset,
  34 };
  35
  36 int meson_aoclkc_probe(struct platform_device *pdev)
  37 {
  38         struct meson_aoclk_reset_controller *rstc;
  39         struct meson_aoclk_data *data;
  40         struct device *dev = &pdev->dev;
  41         struct device_node *np;
  42         struct regmap *regmap;
  43         int ret, clkid;
  44
  45         data = (struct meson_aoclk_data *) of_device_get_match_data(dev);
  46         if (!data)
  47                 return -ENODEV;
  48
  49         rstc = devm_kzalloc(dev, sizeof(*rstc), GFP_KERNEL);
  50         if (!rstc)
  51                 return -ENOMEM;
  52
  53         np = of_get_parent(dev->of_node);
  54         regmap = syscon_node_to_regmap(np);
  55         of_node_put(np);
  56         if (IS_ERR(regmap)) {
  57                 dev_err(dev, "failed to get regmap\n");
  58                 return PTR_ERR(regmap);
  59         }
  60
  61         /* Reset Controller */
  62         rstc->data = data;
  63         rstc->regmap = regmap;
  64         rstc->reset.ops = &meson_aoclk_reset_ops;
  65         rstc->reset.nr_resets = data->num_reset;
  66         rstc->reset.of_node = dev->of_node;
  67         ret = devm_reset_controller_register(dev, &rstc->reset);
  68         if (ret) {
  69                 dev_err(dev, "failed to register reset controller\n");
  70                 return ret;
  71         }
  72
  73         /* Populate regmap */
  74         for (clkid = 0; clkid < data->num_clks; clkid++)
  75                 data->clks[clkid]->map = regmap;
  76
  77         /* Register all clks */
  78         for (clkid = 0; clkid < data->hw_clks.num; clkid++) {
  79                 if (!data->hw_clks.hws[clkid])
  80                         continue;
  81
  82                 ret = devm_clk_hw_register(dev, data->hw_clks.hws[clkid]);
  83                 if (ret) {
  84                         dev_err(dev, "Clock registration failed\n");
  85                         return ret;
  86                 }
  87         }
  88
  89         return devm_of_clk_add_hw_provider(dev, meson_clk_hw_get, (void *)&data->hw_clks);
  90 }
  91 EXPORT_SYMBOL_NS_GPL(meson_aoclkc_probe, "CLK_MESON");
  92
  93 MODULE_DESCRIPTION("Amlogic Always-ON Clock Controller helpers");
  94 MODULE_LICENSE("GPL");
  95 MODULE_IMPORT_NS("CLK_MESON");