drivers/clk/sprd/common.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // Spreadtrum clock infrastructure
   4 //
   5 // Copyright (C) 2017 Spreadtrum, Inc.
   6 // Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
   7
   8 #include <linux/mfd/syscon.h>
   9 #include <linux/module.h>
  10 #include <linux/of_address.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/regmap.h>
  13
  14 #include "common.h"
  15
  16 static const struct regmap_config sprdclk_regmap_config = {
  17         .reg_bits       = 32,
  18         .reg_stride     = 4,
  19         .val_bits       = 32,
  20         .fast_io        = true,
  21 };
  22
  23 static void sprd_clk_set_regmap(const struct sprd_clk_desc *desc,
  24                          struct regmap *regmap)
  25 {
  26         int i;
  27         struct sprd_clk_common *cclk;
  28
  29         for (i = 0; i < desc->num_clk_clks; i++) {
  30                 cclk = desc->clk_clks[i];
  31                 if (!cclk)
  32                         continue;
  33
  34                 cclk->regmap = regmap;
  35         }
  36 }
  37
  38 int sprd_clk_regmap_init(struct platform_device *pdev,
  39                          const struct sprd_clk_desc *desc)
  40 {
  41         void __iomem *base;
  42         struct device *dev = &pdev->dev;
  43         struct device_node *node = dev->of_node, *np;
  44         struct regmap *regmap;
  45         struct resource *res;
  46         struct regmap_config reg_config = sprdclk_regmap_config;
  47
  48         if (of_property_present(node, "sprd,syscon")) {
  49                 regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
  50                 if (IS_ERR(regmap)) {
  51                         pr_err("%s: failed to get syscon regmap\n", __func__);
  52                         return PTR_ERR(regmap);
  53                 }
  54         } else if (of_device_is_compatible(np = of_get_parent(node), "syscon") ||
  55                    (of_node_put(np), 0)) {
  56                 regmap = device_node_to_regmap(np);
  57                 of_node_put(np);
  58                 if (IS_ERR(regmap)) {
  59                         dev_err(dev, "failed to get regmap from its parent.\n");
  60                         return PTR_ERR(regmap);
  61                 }
  62         } else {
  63                 base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
  64                 if (IS_ERR(base))
  65                         return PTR_ERR(base);
  66
  67                 reg_config.max_register = resource_size(res) - reg_config.reg_stride;
  68
  69                 regmap = devm_regmap_init_mmio(&pdev->dev, base,
  70                                                &reg_config);
  71                 if (IS_ERR(regmap)) {
  72                         pr_err("failed to init regmap\n");
  73                         return PTR_ERR(regmap);
  74                 }
  75         }
  76
  77         sprd_clk_set_regmap(desc, regmap);
  78
  79         return 0;
  80 }
  81 EXPORT_SYMBOL_GPL(sprd_clk_regmap_init);
  82
  83 int sprd_clk_probe(struct device *dev, struct clk_hw_onecell_data *clkhw)
  84 {
  85         int i, ret;
  86         struct clk_hw *hw;
  87
  88         for (i = 0; i < clkhw->num; i++) {
  89                 const char *name;
  90
  91                 hw = clkhw->hws[i];
  92                 if (!hw)
  93                         continue;
  94
  95                 name = hw->init->name;
  96                 ret = devm_clk_hw_register(dev, hw);
  97                 if (ret) {
  98                         dev_err(dev, "Couldn't register clock %d - %s\n",
  99                                 i, name);
 100                         return ret;
 101                 }
 102         }
 103
 104         ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clkhw);
 105         if (ret)
 106                 dev_err(dev, "Failed to add clock provider\n");
 107
 108         return ret;
 109 }
 110 EXPORT_SYMBOL_GPL(sprd_clk_probe);
 111
 112 MODULE_DESCRIPTION("Spreadtrum clock infrastructure");
 113 MODULE_LICENSE("GPL v2");