drivers/clk/clk-rk808.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Clkout driver for Rockchip RK808
   4  *
   5  * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
   6  *
   7  * Author:Chris Zhong <zyw@rock-chips.com>
   8  */
   9
  10 #include <linux/clk-provider.h>
  11 #include <linux/module.h>
  12 #include <linux/slab.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/mfd/rk808.h>
  15 #include <linux/i2c.h>
  16
  17 struct rk808_clkout {
  18         struct rk808 *rk808;
  19         struct clk_hw           clkout1_hw;
  20         struct clk_hw           clkout2_hw;
  21 };
  22
  23 static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw,
  24                                               unsigned long parent_rate)
  25 {
  26         return 32768;
  27 }
  28
  29 static int rk808_clkout2_enable(struct clk_hw *hw, bool enable)
  30 {
  31         struct rk808_clkout *rk808_clkout = container_of(hw,
  32                                                          struct rk808_clkout,
  33                                                          clkout2_hw);
  34         struct rk808 *rk808 = rk808_clkout->rk808;
  35
  36         return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG,
  37                                   CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0);
  38 }
  39
  40 static int rk808_clkout2_prepare(struct clk_hw *hw)
  41 {
  42         return rk808_clkout2_enable(hw, true);
  43 }
  44
  45 static void rk808_clkout2_unprepare(struct clk_hw *hw)
  46 {
  47         rk808_clkout2_enable(hw, false);
  48 }
  49
  50 static int rk808_clkout2_is_prepared(struct clk_hw *hw)
  51 {
  52         struct rk808_clkout *rk808_clkout = container_of(hw,
  53                                                          struct rk808_clkout,
  54                                                          clkout2_hw);
  55         struct rk808 *rk808 = rk808_clkout->rk808;
  56         uint32_t val;
  57
  58         int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val);
  59
  60         if (ret < 0)
  61                 return ret;
  62
  63         return (val & CLK32KOUT2_EN) ? 1 : 0;
  64 }
  65
  66 static const struct clk_ops rk808_clkout1_ops = {
  67         .recalc_rate = rk808_clkout_recalc_rate,
  68 };
  69
  70 static const struct clk_ops rk808_clkout2_ops = {
  71         .prepare = rk808_clkout2_prepare,
  72         .unprepare = rk808_clkout2_unprepare,
  73         .is_prepared = rk808_clkout2_is_prepared,
  74         .recalc_rate = rk808_clkout_recalc_rate,
  75 };
  76
  77 static struct clk_hw *
  78 of_clk_rk808_get(struct of_phandle_args *clkspec, void *data)
  79 {
  80         struct rk808_clkout *rk808_clkout = data;
  81         unsigned int idx = clkspec->args[0];
  82
  83         if (idx >= 2) {
  84                 pr_err("%s: invalid index %u\n", __func__, idx);
  85                 return ERR_PTR(-EINVAL);
  86         }
  87
  88         return idx ? &rk808_clkout->clkout2_hw : &rk808_clkout->clkout1_hw;
  89 }
  90
  91 static int rk808_clkout_probe(struct platform_device *pdev)
  92 {
  93         struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
  94         struct i2c_client *client = rk808->i2c;
  95         struct device_node *node = client->dev.of_node;
  96         struct clk_init_data init = {};
  97         struct rk808_clkout *rk808_clkout;
  98         int ret;
  99
 100         rk808_clkout = devm_kzalloc(&client->dev,
 101                                     sizeof(*rk808_clkout), GFP_KERNEL);
 102         if (!rk808_clkout)
 103                 return -ENOMEM;
 104
 105         rk808_clkout->rk808 = rk808;
 106
 107         init.parent_names = NULL;
 108         init.num_parents = 0;
 109         init.name = "rk808-clkout1";
 110         init.ops = &rk808_clkout1_ops;
 111         rk808_clkout->clkout1_hw.init = &init;
 112
 113         /* optional override of the clockname */
 114         of_property_read_string_index(node, "clock-output-names",
 115                                       0, &init.name);
 116
 117         ret = devm_clk_hw_register(&client->dev, &rk808_clkout->clkout1_hw);
 118         if (ret)
 119                 return ret;
 120
 121         init.name = "rk808-clkout2";
 122         init.ops = &rk808_clkout2_ops;
 123         rk808_clkout->clkout2_hw.init = &init;
 124
 125         /* optional override of the clockname */
 126         of_property_read_string_index(node, "clock-output-names",
 127                                       1, &init.name);
 128
 129         ret = devm_clk_hw_register(&client->dev, &rk808_clkout->clkout2_hw);
 130         if (ret)
 131                 return ret;
 132
 133         return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_rk808_get,
 134                                            rk808_clkout);
 135 }
 136
 137 static struct platform_driver rk808_clkout_driver = {
 138         .probe = rk808_clkout_probe,
 139         .driver         = {
 140                 .name   = "rk808-clkout",
 141         },
 142 };
 143
 144 module_platform_driver(rk808_clkout_driver);
 145
 146 MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs");
 147 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
 148 MODULE_LICENSE("GPL");
 149 MODULE_ALIAS("platform:rk808-clkout");