1 /* 2 * Clkout driver for Rockchip RK808 3 * 4 * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd 5 * 6 * Author:Chris Zhong <zyw@rock-chips.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms and conditions of the GNU General Public License, 10 * version 2, as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15 * more details. 16 */ 17 18 #include <linux/clk-provider.h> 19 #include <linux/module.h> 20 #include <linux/slab.h> 21 #include <linux/platform_device.h> 22 #include <linux/mfd/rk808.h> 23 #include <linux/i2c.h> 24 25 struct rk808_clkout { 26 struct rk808 *rk808; 27 struct clk_hw clkout1_hw; 28 struct clk_hw clkout2_hw; 29 }; 30 31 static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw, 32 unsigned long parent_rate) 33 { 34 return 32768; 35 } 36 37 static int rk808_clkout2_enable(struct clk_hw *hw, bool enable) 38 { 39 struct rk808_clkout *rk808_clkout = container_of(hw, 40 struct rk808_clkout, 41 clkout2_hw); 42 struct rk808 *rk808 = rk808_clkout->rk808; 43 44 return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG, 45 CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0); 46 } 47 48 static int rk808_clkout2_prepare(struct clk_hw *hw) 49 { 50 return rk808_clkout2_enable(hw, true); 51 } 52 53 static void rk808_clkout2_unprepare(struct clk_hw *hw) 54 { 55 rk808_clkout2_enable(hw, false); 56 } 57 58 static int rk808_clkout2_is_prepared(struct clk_hw *hw) 59 { 60 struct rk808_clkout *rk808_clkout = container_of(hw, 61 struct rk808_clkout, 62 clkout2_hw); 63 struct rk808 *rk808 = rk808_clkout->rk808; 64 uint32_t val; 65 66 int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val); 67 68 if (ret < 0) 69 return ret; 70 71 return (val & CLK32KOUT2_EN) ? 1 : 0; 72 } 73 74 static const struct clk_ops rk808_clkout1_ops = { 75 .recalc_rate = rk808_clkout_recalc_rate, 76 }; 77 78 static const struct clk_ops rk808_clkout2_ops = { 79 .prepare = rk808_clkout2_prepare, 80 .unprepare = rk808_clkout2_unprepare, 81 .is_prepared = rk808_clkout2_is_prepared, 82 .recalc_rate = rk808_clkout_recalc_rate, 83 }; 84 85 static struct clk_hw * 86 of_clk_rk808_get(struct of_phandle_args *clkspec, void *data) 87 { 88 struct rk808_clkout *rk808_clkout = data; 89 unsigned int idx = clkspec->args[0]; 90 91 if (idx >= 2) { 92 pr_err("%s: invalid index %u\n", __func__, idx); 93 return ERR_PTR(-EINVAL); 94 } 95 96 return idx ? &rk808_clkout->clkout2_hw : &rk808_clkout->clkout1_hw; 97 } 98 99 static int rk808_clkout_probe(struct platform_device *pdev) 100 { 101 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent); 102 struct i2c_client *client = rk808->i2c; 103 struct device_node *node = client->dev.of_node; 104 struct clk_init_data init = {}; 105 struct rk808_clkout *rk808_clkout; 106 int ret; 107 108 rk808_clkout = devm_kzalloc(&client->dev, 109 sizeof(*rk808_clkout), GFP_KERNEL); 110 if (!rk808_clkout) 111 return -ENOMEM; 112 113 rk808_clkout->rk808 = rk808; 114 115 init.parent_names = NULL; 116 init.num_parents = 0; 117 init.name = "rk808-clkout1"; 118 init.ops = &rk808_clkout1_ops; 119 rk808_clkout->clkout1_hw.init = &init; 120 121 /* optional override of the clockname */ 122 of_property_read_string_index(node, "clock-output-names", 123 0, &init.name); 124 125 ret = devm_clk_hw_register(&client->dev, &rk808_clkout->clkout1_hw); 126 if (ret) 127 return ret; 128 129 init.name = "rk808-clkout2"; 130 init.ops = &rk808_clkout2_ops; 131 rk808_clkout->clkout2_hw.init = &init; 132 133 /* optional override of the clockname */ 134 of_property_read_string_index(node, "clock-output-names", 135 1, &init.name); 136 137 ret = devm_clk_hw_register(&client->dev, &rk808_clkout->clkout2_hw); 138 if (ret) 139 return ret; 140 141 return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_rk808_get, 142 rk808_clkout); 143 } 144 145 static struct platform_driver rk808_clkout_driver = { 146 .probe = rk808_clkout_probe, 147 .driver = { 148 .name = "rk808-clkout", 149 }, 150 }; 151 152 module_platform_driver(rk808_clkout_driver); 153 154 MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs"); 155 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>"); 156 MODULE_LICENSE("GPL"); 157 MODULE_ALIAS("platform:rk808-clkout"); 158