drivers/clk/versatile/clk-impd1.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Clock driver for the ARM Integrator/IM-PD1 board
   4  * Copyright (C) 2012-2013 Linus Walleij
   5  */
   6 #include <linux/clk-provider.h>
   7 #include <linux/clkdev.h>
   8 #include <linux/err.h>
   9 #include <linux/io.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/module.h>
  12 #include <linux/mfd/syscon.h>
  13 #include <linux/regmap.h>
  14
  15 #include "icst.h"
  16 #include "clk-icst.h"
  17
  18 #define IMPD1_OSC1      0x00
  19 #define IMPD1_OSC2      0x04
  20 #define IMPD1_LOCK      0x08
  21
  22 /*
  23  * There are two VCO's on the IM-PD1
  24  */
  25
  26 static const struct icst_params impd1_vco1_params = {
  27         .ref            = 24000000,     /* 24 MHz */
  28         .vco_max        = ICST525_VCO_MAX_3V,
  29         .vco_min        = ICST525_VCO_MIN,
  30         .vd_min         = 12,
  31         .vd_max         = 519,
  32         .rd_min         = 3,
  33         .rd_max         = 120,
  34         .s2div          = icst525_s2div,
  35         .idx2s          = icst525_idx2s,
  36 };
  37
  38 static const struct clk_icst_desc impd1_icst1_desc = {
  39         .params = &impd1_vco1_params,
  40         .vco_offset = IMPD1_OSC1,
  41         .lock_offset = IMPD1_LOCK,
  42 };
  43
  44 static const struct icst_params impd1_vco2_params = {
  45         .ref            = 24000000,     /* 24 MHz */
  46         .vco_max        = ICST525_VCO_MAX_3V,
  47         .vco_min        = ICST525_VCO_MIN,
  48         .vd_min         = 12,
  49         .vd_max         = 519,
  50         .rd_min         = 3,
  51         .rd_max         = 120,
  52         .s2div          = icst525_s2div,
  53         .idx2s          = icst525_idx2s,
  54 };
  55
  56 static const struct clk_icst_desc impd1_icst2_desc = {
  57         .params = &impd1_vco2_params,
  58         .vco_offset = IMPD1_OSC2,
  59         .lock_offset = IMPD1_LOCK,
  60 };
  61
  62 static int integrator_impd1_clk_spawn(struct device *dev,
  63                                       struct device_node *parent,
  64                                       struct device_node *np)
  65 {
  66         struct regmap *map;
  67         struct clk *clk = ERR_PTR(-EINVAL);
  68         const char *name = np->name;
  69         const char *parent_name;
  70         const struct clk_icst_desc *desc;
  71         int ret;
  72
  73         map = syscon_node_to_regmap(parent);
  74         if (IS_ERR(map)) {
  75                 pr_err("no regmap for syscon IM-PD1 ICST clock parent\n");
  76                 return PTR_ERR(map);
  77         }
  78
  79         if (of_device_is_compatible(np, "arm,impd1-vco1")) {
  80                 desc = &impd1_icst1_desc;
  81         } else if (of_device_is_compatible(np, "arm,impd1-vco2")) {
  82                 desc = &impd1_icst2_desc;
  83         } else {
  84                 dev_err(dev, "not a clock node %s\n", name);
  85                 return -ENODEV;
  86         }
  87
  88         of_property_read_string(np, "clock-output-names", &name);
  89         parent_name = of_clk_get_parent_name(np, 0);
  90         clk = icst_clk_setup(NULL, desc, name, parent_name, map,
  91                              ICST_INTEGRATOR_IM_PD1);
  92         if (!IS_ERR(clk)) {
  93                 of_clk_add_provider(np, of_clk_src_simple_get, clk);
  94                 ret = 0;
  95         } else {
  96                 dev_err(dev, "error setting up IM-PD1 ICST clock\n");
  97                 ret = PTR_ERR(clk);
  98         }
  99
 100         return ret;
 101 }
 102
 103 static int integrator_impd1_clk_probe(struct platform_device *pdev)
 104 {
 105         struct device *dev = &pdev->dev;
 106         struct device_node *np = dev->of_node;
 107         struct device_node *child;
 108         int ret = 0;
 109
 110         for_each_available_child_of_node(np, child) {
 111                 ret = integrator_impd1_clk_spawn(dev, np, child);
 112                 if (ret) {
 113                         of_node_put(child);
 114                         break;
 115                 }
 116         }
 117
 118         return ret;
 119 }
 120
 121 static const struct of_device_id impd1_syscon_match[] = {
 122         { .compatible = "arm,im-pd1-syscon", },
 123         {}
 124 };
 125 MODULE_DEVICE_TABLE(of, impd1_syscon_match);
 126
 127 static struct platform_driver impd1_clk_driver = {
 128         .driver = {
 129                 .name = "impd1-clk",
 130                 .of_match_table = impd1_syscon_match,
 131         },
 132         .probe  = integrator_impd1_clk_probe,
 133 };
 134 builtin_platform_driver(impd1_clk_driver);
 135
 136 MODULE_AUTHOR("Linus Walleij <linusw@kernel.org>");
 137 MODULE_DESCRIPTION("Arm IM-PD1 module clock driver");
 138 MODULE_LICENSE("GPL v2");