1 /* 2 * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved. 3 */ 4 5 /* 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your 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 along 17 * with this program; if not, write to the Free Software Foundation, Inc., 18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 19 */ 20 21 #include <linux/slab.h> 22 #include <linux/device.h> 23 #include <linux/module.h> 24 #include <linux/mfd/syscon.h> 25 #include <linux/err.h> 26 #include <linux/io.h> 27 #include <linux/platform_device.h> 28 #include <linux/of.h> 29 #include <linux/of_address.h> 30 #include <linux/regmap.h> 31 #include <linux/regulator/driver.h> 32 #include <linux/regulator/of_regulator.h> 33 34 #define LDO_RAMP_UP_UNIT_IN_CYCLES 64 /* 64 cycles per step */ 35 #define LDO_RAMP_UP_FREQ_IN_MHZ 24 /* cycle based on 24M OSC */ 36 37 struct anatop_regulator { 38 const char *name; 39 u32 control_reg; 40 struct regmap *anatop; 41 int vol_bit_shift; 42 int vol_bit_width; 43 u32 delay_reg; 44 int delay_bit_shift; 45 int delay_bit_width; 46 int min_bit_val; 47 int min_voltage; 48 int max_voltage; 49 struct regulator_desc rdesc; 50 struct regulator_init_data *initdata; 51 }; 52 53 static int anatop_regmap_set_voltage_sel(struct regulator_dev *reg, 54 unsigned selector) 55 { 56 struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); 57 58 if (!anatop_reg->control_reg) 59 return -ENOTSUPP; 60 61 return regulator_set_voltage_sel_regmap(reg, selector); 62 } 63 64 static int anatop_regmap_set_voltage_time_sel(struct regulator_dev *reg, 65 unsigned int old_sel, 66 unsigned int new_sel) 67 { 68 struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); 69 u32 val; 70 int ret = 0; 71 72 /* check whether need to care about LDO ramp up speed */ 73 if (anatop_reg->delay_bit_width && new_sel > old_sel) { 74 /* 75 * the delay for LDO ramp up time is 76 * based on the register setting, we need 77 * to calculate how many steps LDO need to 78 * ramp up, and how much delay needed. (us) 79 */ 80 regmap_read(anatop_reg->anatop, anatop_reg->delay_reg, &val); 81 val = (val >> anatop_reg->delay_bit_shift) & 82 ((1 << anatop_reg->delay_bit_width) - 1); 83 ret = (new_sel - old_sel) * (LDO_RAMP_UP_UNIT_IN_CYCLES << 84 val) / LDO_RAMP_UP_FREQ_IN_MHZ + 1; 85 } 86 87 return ret; 88 } 89 90 static int anatop_regmap_get_voltage_sel(struct regulator_dev *reg) 91 { 92 struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); 93 94 if (!anatop_reg->control_reg) 95 return -ENOTSUPP; 96 97 return regulator_get_voltage_sel_regmap(reg); 98 } 99 100 static struct regulator_ops anatop_rops = { 101 .set_voltage_sel = anatop_regmap_set_voltage_sel, 102 .set_voltage_time_sel = anatop_regmap_set_voltage_time_sel, 103 .get_voltage_sel = anatop_regmap_get_voltage_sel, 104 .list_voltage = regulator_list_voltage_linear, 105 .map_voltage = regulator_map_voltage_linear, 106 }; 107 108 static int anatop_regulator_probe(struct platform_device *pdev) 109 { 110 struct device *dev = &pdev->dev; 111 struct device_node *np = dev->of_node; 112 struct device_node *anatop_np; 113 struct regulator_desc *rdesc; 114 struct regulator_dev *rdev; 115 struct anatop_regulator *sreg; 116 struct regulator_init_data *initdata; 117 struct regulator_config config = { }; 118 int ret = 0; 119 120 initdata = of_get_regulator_init_data(dev, np); 121 sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL); 122 if (!sreg) 123 return -ENOMEM; 124 sreg->initdata = initdata; 125 sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL), 126 GFP_KERNEL); 127 rdesc = &sreg->rdesc; 128 memset(rdesc, 0, sizeof(*rdesc)); 129 rdesc->name = sreg->name; 130 rdesc->ops = &anatop_rops; 131 rdesc->type = REGULATOR_VOLTAGE; 132 rdesc->owner = THIS_MODULE; 133 134 anatop_np = of_get_parent(np); 135 if (!anatop_np) 136 return -ENODEV; 137 sreg->anatop = syscon_node_to_regmap(anatop_np); 138 of_node_put(anatop_np); 139 if (IS_ERR(sreg->anatop)) 140 return PTR_ERR(sreg->anatop); 141 142 ret = of_property_read_u32(np, "anatop-reg-offset", 143 &sreg->control_reg); 144 if (ret) { 145 dev_err(dev, "no anatop-reg-offset property set\n"); 146 goto anatop_probe_end; 147 } 148 ret = of_property_read_u32(np, "anatop-vol-bit-width", 149 &sreg->vol_bit_width); 150 if (ret) { 151 dev_err(dev, "no anatop-vol-bit-width property set\n"); 152 goto anatop_probe_end; 153 } 154 ret = of_property_read_u32(np, "anatop-vol-bit-shift", 155 &sreg->vol_bit_shift); 156 if (ret) { 157 dev_err(dev, "no anatop-vol-bit-shift property set\n"); 158 goto anatop_probe_end; 159 } 160 ret = of_property_read_u32(np, "anatop-min-bit-val", 161 &sreg->min_bit_val); 162 if (ret) { 163 dev_err(dev, "no anatop-min-bit-val property set\n"); 164 goto anatop_probe_end; 165 } 166 ret = of_property_read_u32(np, "anatop-min-voltage", 167 &sreg->min_voltage); 168 if (ret) { 169 dev_err(dev, "no anatop-min-voltage property set\n"); 170 goto anatop_probe_end; 171 } 172 ret = of_property_read_u32(np, "anatop-max-voltage", 173 &sreg->max_voltage); 174 if (ret) { 175 dev_err(dev, "no anatop-max-voltage property set\n"); 176 goto anatop_probe_end; 177 } 178 179 /* read LDO ramp up setting, only for core reg */ 180 of_property_read_u32(np, "anatop-delay-reg-offset", 181 &sreg->delay_reg); 182 of_property_read_u32(np, "anatop-delay-bit-width", 183 &sreg->delay_bit_width); 184 of_property_read_u32(np, "anatop-delay-bit-shift", 185 &sreg->delay_bit_shift); 186 187 rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) / 25000 + 1 188 + sreg->min_bit_val; 189 rdesc->min_uV = sreg->min_voltage; 190 rdesc->uV_step = 25000; 191 rdesc->linear_min_sel = sreg->min_bit_val; 192 rdesc->vsel_reg = sreg->control_reg; 193 rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) << 194 sreg->vol_bit_shift; 195 196 config.dev = &pdev->dev; 197 config.init_data = initdata; 198 config.driver_data = sreg; 199 config.of_node = pdev->dev.of_node; 200 config.regmap = sreg->anatop; 201 202 /* register regulator */ 203 rdev = regulator_register(rdesc, &config); 204 if (IS_ERR(rdev)) { 205 dev_err(dev, "failed to register %s\n", 206 rdesc->name); 207 ret = PTR_ERR(rdev); 208 goto anatop_probe_end; 209 } 210 211 platform_set_drvdata(pdev, rdev); 212 213 anatop_probe_end: 214 if (ret) 215 kfree(sreg->name); 216 217 return ret; 218 } 219 220 static int anatop_regulator_remove(struct platform_device *pdev) 221 { 222 struct regulator_dev *rdev = platform_get_drvdata(pdev); 223 struct anatop_regulator *sreg = rdev_get_drvdata(rdev); 224 const char *name = sreg->name; 225 226 regulator_unregister(rdev); 227 kfree(name); 228 229 return 0; 230 } 231 232 static struct of_device_id of_anatop_regulator_match_tbl[] = { 233 { .compatible = "fsl,anatop-regulator", }, 234 { /* end */ } 235 }; 236 237 static struct platform_driver anatop_regulator_driver = { 238 .driver = { 239 .name = "anatop_regulator", 240 .owner = THIS_MODULE, 241 .of_match_table = of_anatop_regulator_match_tbl, 242 }, 243 .probe = anatop_regulator_probe, 244 .remove = anatop_regulator_remove, 245 }; 246 247 static int __init anatop_regulator_init(void) 248 { 249 return platform_driver_register(&anatop_regulator_driver); 250 } 251 postcore_initcall(anatop_regulator_init); 252 253 static void __exit anatop_regulator_exit(void) 254 { 255 platform_driver_unregister(&anatop_regulator_driver); 256 } 257 module_exit(anatop_regulator_exit); 258 259 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>, " 260 "Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>"); 261 MODULE_DESCRIPTION("ANATOP Regulator driver"); 262 MODULE_LICENSE("GPL v2"); 263