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.h> 19 #include <linux/clk-provider.h> 20 #include <linux/module.h> 21 #include <linux/slab.h> 22 #include <linux/platform_device.h> 23 #include <linux/mfd/rk808.h> 24 #include <linux/i2c.h> 25 26 #define RK808_NR_OUTPUT 2 27 28 struct rk808_clkout { 29 struct rk808 *rk808; 30 struct clk_onecell_data clk_data; 31 struct clk_hw clkout1_hw; 32 struct clk_hw clkout2_hw; 33 }; 34 35 static unsigned long rk808_clkout_recalc_rate(struct clk_hw *hw, 36 unsigned long parent_rate) 37 { 38 return 32768; 39 } 40 41 static int rk808_clkout2_enable(struct clk_hw *hw, bool enable) 42 { 43 struct rk808_clkout *rk808_clkout = container_of(hw, 44 struct rk808_clkout, 45 clkout2_hw); 46 struct rk808 *rk808 = rk808_clkout->rk808; 47 48 return regmap_update_bits(rk808->regmap, RK808_CLK32OUT_REG, 49 CLK32KOUT2_EN, enable ? CLK32KOUT2_EN : 0); 50 } 51 52 static int rk808_clkout2_prepare(struct clk_hw *hw) 53 { 54 return rk808_clkout2_enable(hw, true); 55 } 56 57 static void rk808_clkout2_unprepare(struct clk_hw *hw) 58 { 59 rk808_clkout2_enable(hw, false); 60 } 61 62 static int rk808_clkout2_is_prepared(struct clk_hw *hw) 63 { 64 struct rk808_clkout *rk808_clkout = container_of(hw, 65 struct rk808_clkout, 66 clkout2_hw); 67 struct rk808 *rk808 = rk808_clkout->rk808; 68 uint32_t val; 69 70 int ret = regmap_read(rk808->regmap, RK808_CLK32OUT_REG, &val); 71 72 if (ret < 0) 73 return ret; 74 75 return (val & CLK32KOUT2_EN) ? 1 : 0; 76 } 77 78 static const struct clk_ops rk808_clkout1_ops = { 79 .recalc_rate = rk808_clkout_recalc_rate, 80 }; 81 82 static const struct clk_ops rk808_clkout2_ops = { 83 .prepare = rk808_clkout2_prepare, 84 .unprepare = rk808_clkout2_unprepare, 85 .is_prepared = rk808_clkout2_is_prepared, 86 .recalc_rate = rk808_clkout_recalc_rate, 87 }; 88 89 static int rk808_clkout_probe(struct platform_device *pdev) 90 { 91 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent); 92 struct i2c_client *client = rk808->i2c; 93 struct device_node *node = client->dev.of_node; 94 struct clk_init_data init = {}; 95 struct clk **clk_table; 96 struct rk808_clkout *rk808_clkout; 97 98 rk808_clkout = devm_kzalloc(&client->dev, 99 sizeof(*rk808_clkout), GFP_KERNEL); 100 if (!rk808_clkout) 101 return -ENOMEM; 102 103 rk808_clkout->rk808 = rk808; 104 105 clk_table = devm_kcalloc(&client->dev, RK808_NR_OUTPUT, 106 sizeof(struct clk *), GFP_KERNEL); 107 if (!clk_table) 108 return -ENOMEM; 109 110 init.flags = CLK_IS_ROOT; 111 init.parent_names = NULL; 112 init.num_parents = 0; 113 init.name = "rk808-clkout1"; 114 init.ops = &rk808_clkout1_ops; 115 rk808_clkout->clkout1_hw.init = &init; 116 117 /* optional override of the clockname */ 118 of_property_read_string_index(node, "clock-output-names", 119 0, &init.name); 120 121 clk_table[0] = devm_clk_register(&client->dev, 122 &rk808_clkout->clkout1_hw); 123 if (IS_ERR(clk_table[0])) 124 return PTR_ERR(clk_table[0]); 125 126 init.name = "rk808-clkout2"; 127 init.ops = &rk808_clkout2_ops; 128 rk808_clkout->clkout2_hw.init = &init; 129 130 /* optional override of the clockname */ 131 of_property_read_string_index(node, "clock-output-names", 132 1, &init.name); 133 134 clk_table[1] = devm_clk_register(&client->dev, 135 &rk808_clkout->clkout2_hw); 136 if (IS_ERR(clk_table[1])) 137 return PTR_ERR(clk_table[1]); 138 139 rk808_clkout->clk_data.clks = clk_table; 140 rk808_clkout->clk_data.clk_num = RK808_NR_OUTPUT; 141 142 return of_clk_add_provider(node, of_clk_src_onecell_get, 143 &rk808_clkout->clk_data); 144 } 145 146 static int rk808_clkout_remove(struct platform_device *pdev) 147 { 148 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent); 149 struct i2c_client *client = rk808->i2c; 150 struct device_node *node = client->dev.of_node; 151 152 of_clk_del_provider(node); 153 154 return 0; 155 } 156 157 static struct platform_driver rk808_clkout_driver = { 158 .probe = rk808_clkout_probe, 159 .remove = rk808_clkout_remove, 160 .driver = { 161 .name = "rk808-clkout", 162 }, 163 }; 164 165 module_platform_driver(rk808_clkout_driver); 166 167 MODULE_DESCRIPTION("Clkout driver for the rk808 series PMICs"); 168 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>"); 169 MODULE_LICENSE("GPL"); 170 MODULE_ALIAS("platform:rk808-clkout"); 171