1 /* 2 * clk-s2mps11.c - Clock driver for S2MPS11. 3 * 4 * Copyright (C) 2013 Samsung Electornics 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the 8 * Free Software Foundation; either version 2 of the License, or (at your 9 * option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 */ 21 22 #include <linux/module.h> 23 #include <linux/err.h> 24 #include <linux/of.h> 25 #include <linux/clkdev.h> 26 #include <linux/regmap.h> 27 #include <linux/clk-provider.h> 28 #include <linux/platform_device.h> 29 #include <linux/mfd/samsung/s2mps11.h> 30 #include <linux/mfd/samsung/core.h> 31 32 #define s2mps11_name(a) (a->hw.init->name) 33 34 static struct clk **clk_table; 35 static struct clk_onecell_data clk_data; 36 37 enum { 38 S2MPS11_CLK_AP = 0, 39 S2MPS11_CLK_CP, 40 S2MPS11_CLK_BT, 41 S2MPS11_CLKS_NUM, 42 }; 43 44 struct s2mps11_clk { 45 struct sec_pmic_dev *iodev; 46 struct clk_hw hw; 47 struct clk *clk; 48 struct clk_lookup *lookup; 49 u32 mask; 50 bool enabled; 51 }; 52 53 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw) 54 { 55 return container_of(hw, struct s2mps11_clk, hw); 56 } 57 58 static int s2mps11_clk_prepare(struct clk_hw *hw) 59 { 60 struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw); 61 int ret; 62 63 ret = regmap_update_bits(s2mps11->iodev->regmap_pmic, 64 S2MPS11_REG_RTC_CTRL, 65 s2mps11->mask, s2mps11->mask); 66 if (!ret) 67 s2mps11->enabled = true; 68 69 return ret; 70 } 71 72 static void s2mps11_clk_unprepare(struct clk_hw *hw) 73 { 74 struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw); 75 int ret; 76 77 ret = regmap_update_bits(s2mps11->iodev->regmap_pmic, S2MPS11_REG_RTC_CTRL, 78 s2mps11->mask, ~s2mps11->mask); 79 80 if (!ret) 81 s2mps11->enabled = false; 82 } 83 84 static int s2mps11_clk_is_enabled(struct clk_hw *hw) 85 { 86 struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw); 87 88 return s2mps11->enabled; 89 } 90 91 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw, 92 unsigned long parent_rate) 93 { 94 struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw); 95 if (s2mps11->enabled) 96 return 32768; 97 else 98 return 0; 99 } 100 101 static struct clk_ops s2mps11_clk_ops = { 102 .prepare = s2mps11_clk_prepare, 103 .unprepare = s2mps11_clk_unprepare, 104 .is_enabled = s2mps11_clk_is_enabled, 105 .recalc_rate = s2mps11_clk_recalc_rate, 106 }; 107 108 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = { 109 [S2MPS11_CLK_AP] = { 110 .name = "s2mps11_ap", 111 .ops = &s2mps11_clk_ops, 112 .flags = CLK_IS_ROOT, 113 }, 114 [S2MPS11_CLK_CP] = { 115 .name = "s2mps11_cp", 116 .ops = &s2mps11_clk_ops, 117 .flags = CLK_IS_ROOT, 118 }, 119 [S2MPS11_CLK_BT] = { 120 .name = "s2mps11_bt", 121 .ops = &s2mps11_clk_ops, 122 .flags = CLK_IS_ROOT, 123 }, 124 }; 125 126 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev) 127 { 128 struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent); 129 struct device_node *clk_np; 130 int i; 131 132 if (!iodev->dev->of_node) 133 return NULL; 134 135 clk_np = of_find_node_by_name(iodev->dev->of_node, "clocks"); 136 if (!clk_np) { 137 dev_err(&pdev->dev, "could not find clock sub-node\n"); 138 return ERR_PTR(-EINVAL); 139 } 140 141 clk_table = devm_kzalloc(&pdev->dev, sizeof(struct clk *) * 142 S2MPS11_CLKS_NUM, GFP_KERNEL); 143 if (!clk_table) 144 return ERR_PTR(-ENOMEM); 145 146 for (i = 0; i < S2MPS11_CLKS_NUM; i++) 147 of_property_read_string_index(clk_np, "clock-output-names", i, 148 &s2mps11_clks_init[i].name); 149 150 return clk_np; 151 } 152 153 static int s2mps11_clk_probe(struct platform_device *pdev) 154 { 155 struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent); 156 struct s2mps11_clk *s2mps11_clks, *s2mps11_clk; 157 struct device_node *clk_np = NULL; 158 int i, ret = 0; 159 u32 val; 160 161 s2mps11_clks = devm_kzalloc(&pdev->dev, sizeof(*s2mps11_clk) * 162 S2MPS11_CLKS_NUM, GFP_KERNEL); 163 if (!s2mps11_clks) 164 return -ENOMEM; 165 166 s2mps11_clk = s2mps11_clks; 167 168 clk_np = s2mps11_clk_parse_dt(pdev); 169 if (IS_ERR(clk_np)) 170 return PTR_ERR(clk_np); 171 172 for (i = 0; i < S2MPS11_CLKS_NUM; i++, s2mps11_clk++) { 173 s2mps11_clk->iodev = iodev; 174 s2mps11_clk->hw.init = &s2mps11_clks_init[i]; 175 s2mps11_clk->mask = 1 << i; 176 177 ret = regmap_read(s2mps11_clk->iodev->regmap_pmic, 178 S2MPS11_REG_RTC_CTRL, &val); 179 if (ret < 0) 180 goto err_reg; 181 182 s2mps11_clk->enabled = val & s2mps11_clk->mask; 183 184 s2mps11_clk->clk = devm_clk_register(&pdev->dev, 185 &s2mps11_clk->hw); 186 if (IS_ERR(s2mps11_clk->clk)) { 187 dev_err(&pdev->dev, "Fail to register : %s\n", 188 s2mps11_name(s2mps11_clk)); 189 ret = PTR_ERR(s2mps11_clk->clk); 190 goto err_reg; 191 } 192 193 s2mps11_clk->lookup = devm_kzalloc(&pdev->dev, 194 sizeof(struct clk_lookup), GFP_KERNEL); 195 if (!s2mps11_clk->lookup) { 196 ret = -ENOMEM; 197 goto err_lup; 198 } 199 200 s2mps11_clk->lookup->con_id = s2mps11_name(s2mps11_clk); 201 s2mps11_clk->lookup->clk = s2mps11_clk->clk; 202 203 clkdev_add(s2mps11_clk->lookup); 204 } 205 206 if (clk_table) { 207 for (i = 0; i < S2MPS11_CLKS_NUM; i++) 208 clk_table[i] = s2mps11_clks[i].clk; 209 210 clk_data.clks = clk_table; 211 clk_data.clk_num = S2MPS11_CLKS_NUM; 212 of_clk_add_provider(clk_np, of_clk_src_onecell_get, &clk_data); 213 } 214 215 platform_set_drvdata(pdev, s2mps11_clks); 216 217 return ret; 218 err_lup: 219 devm_clk_unregister(&pdev->dev, s2mps11_clk->clk); 220 err_reg: 221 while (s2mps11_clk > s2mps11_clks) { 222 if (s2mps11_clk->lookup) { 223 clkdev_drop(s2mps11_clk->lookup); 224 devm_clk_unregister(&pdev->dev, s2mps11_clk->clk); 225 } 226 s2mps11_clk--; 227 } 228 229 return ret; 230 } 231 232 static int s2mps11_clk_remove(struct platform_device *pdev) 233 { 234 struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev); 235 int i; 236 237 for (i = 0; i < S2MPS11_CLKS_NUM; i++) 238 clkdev_drop(s2mps11_clks[i].lookup); 239 240 return 0; 241 } 242 243 static const struct platform_device_id s2mps11_clk_id[] = { 244 { "s2mps11-clk", 0}, 245 { }, 246 }; 247 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id); 248 249 static struct platform_driver s2mps11_clk_driver = { 250 .driver = { 251 .name = "s2mps11-clk", 252 .owner = THIS_MODULE, 253 }, 254 .probe = s2mps11_clk_probe, 255 .remove = s2mps11_clk_remove, 256 .id_table = s2mps11_clk_id, 257 }; 258 259 static int __init s2mps11_clk_init(void) 260 { 261 return platform_driver_register(&s2mps11_clk_driver); 262 } 263 subsys_initcall(s2mps11_clk_init); 264 265 static void __init s2mps11_clk_cleanup(void) 266 { 267 platform_driver_unregister(&s2mps11_clk_driver); 268 } 269 module_exit(s2mps11_clk_cleanup); 270 271 MODULE_DESCRIPTION("S2MPS11 Clock Driver"); 272 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>"); 273 MODULE_LICENSE("GPL"); 274