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 #define RK808_NR_OUTPUT 2 26 27 struct rk808_clkout { 28 struct rk808 *rk808; 29 struct clk_onecell_data clk_data; 30 struct clk_hw clkout1_hw; 31 struct clk_hw clkout2_hw; 32 }; 33 34 static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw, 35 unsigned long parent_rate) 36 { 37 return 32768; 38 } 39 40 static int rk808_clkout2_enable(struct clk_hw *hw, bool enable) 41 { 42 struct rk808_clkout *rk808_clkout = container_of(hw, 43 struct rk808_clkout, 44 clkout2_hw); 45 struct rk808 *rk808 = rk808_clkout->rk808; 46 47 return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG, 48 CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0); 49 } 50 51 static int rk808_clkout2_prepare(struct clk_hw *hw) 52 { 53 return rk808_clkout2_enable(hw, true); 54 } 55 56 static void rk808_clkout2_unprepare(struct clk_hw *hw) 57 { 58 rk808_clkout2_enable(hw, false); 59 } 60 61 static int rk808_clkout2_is_prepared(struct clk_hw *hw) 62 { 63 struct rk808_clkout *rk808_clkout = container_of(hw, 64 struct rk808_clkout, 65 clkout2_hw); 66 struct rk808 *rk808 = rk808_clkout->rk808; 67 uint32_t val; 68 69 int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val); 70 71 if (ret < 0) 72 return ret; 73 74 return (val & CLK32KOUT2_EN) ? 1 : 0; 75 } 76 77 static const struct clk_ops rk808_clkout1_ops = { 78 .recalc_rate = rk808_clkout_recalc_rate, 79 }; 80 81 static const struct clk_ops rk808_clkout2_ops = { 82 .prepare = rk808_clkout2_prepare, 83 .unprepare = rk808_clkout2_unprepare, 84 .is_prepared = rk808_clkout2_is_prepared, 85 .recalc_rate = rk808_clkout_recalc_rate, 86 }; 87 88 static int rk808_clkout_probe(struct platform_device *pdev) 89 { 90 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent); 91 struct i2c_client *client = rk808->i2c; 92 struct device_node *node = client->dev.of_node; 93 struct clk_init_data init = {}; 94 struct clk **clk_table; 95 struct rk808_clkout *rk808_clkout; 96 97 rk808_clkout = devm_kzalloc(&client->dev, 98 sizeof(*rk808_clkout), GFP_KERNEL); 99 if (!rk808_clkout) 100 return -ENOMEM; 101 102 rk808_clkout->rk808 = rk808; 103 104 clk_table = devm_kcalloc(&client->dev, RK808_NR_OUTPUT, 105 sizeof(struct clk *), GFP_KERNEL); 106 if (!clk_table) 107 return -ENOMEM; 108 109 init.flags = CLK_IS_ROOT; 110 init.parent_names = NULL; 111 init.num_parents = 0; 112 init.name = "rk808-clkout1"; 113 init.ops = &rk808_clkout1_ops; 114 rk808_clkout->clkout1_hw.init = &init; 115 116 /* optional override of the clockname */ 117 of_property_read_string_index(node, "clock-output-names", 118 0, &init.name); 119 120 clk_table[0] = devm_clk_register(&client->dev, 121 &rk808_clkout->clkout1_hw); 122 if (IS_ERR(clk_table[0])) 123 return PTR_ERR(clk_table[0]); 124 125 init.name = "rk808-clkout2"; 126 init.ops = &rk808_clkout2_ops; 127 rk808_clkout->clkout2_hw.init = &init; 128 129 /* optional override of the clockname */ 130 of_property_read_string_index(node, "clock-output-names", 131 1, &init.name); 132 133 clk_table[1] = devm_clk_register(&client->dev, 134 &rk808_clkout->clkout2_hw); 135 if (IS_ERR(clk_table[1])) 136 return PTR_ERR(clk_table[1]); 137 138 rk808_clkout->clk_data.clks = clk_table; 139 rk808_clkout->clk_data.clk_num = RK808_NR_OUTPUT; 140 141 return of_clk_add_provider(node, of_clk_src_onecell_get, 142 &rk808_clkout->clk_data); 143 } 144 145 static int rk808_clkout_remove(struct platform_device *pdev) 146 { 147 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent); 148 struct i2c_client *client = rk808->i2c; 149 struct device_node *node = client->dev.of_node; 150 151 of_clk_del_provider(node); 152 153 return 0; 154 } 155 156 static struct platform_driver rk808_clkout_driver = { 157 .probe = rk808_clkout_probe, 158 .remove = rk808_clkout_remove, 159 .driver = { 160 .name = "rk808-clkout", 161 }, 162 }; 163 164 module_platform_driver(rk808_clkout_driver); 165 166 MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs"); 167 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>"); 168 MODULE_LICENSE("GPL"); 169 MODULE_ALIAS("platform:rk808-clkout"); 170