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/err.h> 25 #include <linux/io.h> 26 #include <linux/platform_device.h> 27 #include <linux/of.h> 28 #include <linux/of_address.h> 29 #include <linux/mfd/anatop.h> 30 #include <linux/regulator/driver.h> 31 #include <linux/regulator/of_regulator.h> 32 33 struct anatop_regulator { 34 const char *name; 35 u32 control_reg; 36 struct anatop *mfd; 37 int vol_bit_shift; 38 int vol_bit_width; 39 int min_bit_val; 40 int min_voltage; 41 int max_voltage; 42 struct regulator_desc rdesc; 43 struct regulator_init_data *initdata; 44 }; 45 46 static int anatop_set_voltage(struct regulator_dev *reg, int min_uV, 47 int max_uV, unsigned *selector) 48 { 49 struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); 50 u32 val, sel; 51 int uv; 52 53 uv = min_uV; 54 dev_dbg(®->dev, "%s: uv %d, min %d, max %d\n", __func__, 55 uv, anatop_reg->min_voltage, 56 anatop_reg->max_voltage); 57 58 if (uv < anatop_reg->min_voltage) { 59 if (max_uV > anatop_reg->min_voltage) 60 uv = anatop_reg->min_voltage; 61 else 62 return -EINVAL; 63 } 64 65 if (!anatop_reg->control_reg) 66 return -ENOTSUPP; 67 68 sel = DIV_ROUND_UP(uv - anatop_reg->min_voltage, 25000); 69 if (sel * 25000 + anatop_reg->min_voltage > anatop_reg->max_voltage) 70 return -EINVAL; 71 val = anatop_reg->min_bit_val + sel; 72 *selector = sel; 73 dev_dbg(®->dev, "%s: calculated val %d\n", __func__, val); 74 anatop_set_bits(anatop_reg->mfd, 75 anatop_reg->control_reg, 76 anatop_reg->vol_bit_shift, 77 anatop_reg->vol_bit_width, 78 val); 79 80 return 0; 81 } 82 83 static int anatop_get_voltage_sel(struct regulator_dev *reg) 84 { 85 struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); 86 u32 val; 87 88 if (!anatop_reg->control_reg) 89 return -ENOTSUPP; 90 91 val = anatop_get_bits(anatop_reg->mfd, 92 anatop_reg->control_reg, 93 anatop_reg->vol_bit_shift, 94 anatop_reg->vol_bit_width); 95 96 return val - anatop_reg->min_bit_val; 97 } 98 99 static int anatop_list_voltage(struct regulator_dev *reg, unsigned selector) 100 { 101 struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg); 102 int uv; 103 104 uv = anatop_reg->min_voltage + selector * 25000; 105 dev_dbg(®->dev, "vddio = %d, selector = %u\n", uv, selector); 106 107 return uv; 108 } 109 110 static struct regulator_ops anatop_rops = { 111 .set_voltage = anatop_set_voltage, 112 .get_voltage_sel = anatop_get_voltage_sel, 113 .list_voltage = anatop_list_voltage, 114 }; 115 116 static int __devinit anatop_regulator_probe(struct platform_device *pdev) 117 { 118 struct device *dev = &pdev->dev; 119 struct device_node *np = dev->of_node; 120 struct regulator_desc *rdesc; 121 struct regulator_dev *rdev; 122 struct anatop_regulator *sreg; 123 struct regulator_init_data *initdata; 124 struct anatop *anatopmfd = dev_get_drvdata(pdev->dev.parent); 125 int ret = 0; 126 127 initdata = of_get_regulator_init_data(dev, np); 128 sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL); 129 if (!sreg) 130 return -ENOMEM; 131 sreg->initdata = initdata; 132 sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL), 133 GFP_KERNEL); 134 rdesc = &sreg->rdesc; 135 memset(rdesc, 0, sizeof(*rdesc)); 136 rdesc->name = sreg->name; 137 rdesc->ops = &anatop_rops; 138 rdesc->type = REGULATOR_VOLTAGE; 139 rdesc->owner = THIS_MODULE; 140 sreg->mfd = anatopmfd; 141 ret = of_property_read_u32(np, "anatop-reg-offset", 142 &sreg->control_reg); 143 if (ret) { 144 dev_err(dev, "no anatop-reg-offset property set\n"); 145 goto anatop_probe_end; 146 } 147 ret = of_property_read_u32(np, "anatop-vol-bit-width", 148 &sreg->vol_bit_width); 149 if (ret) { 150 dev_err(dev, "no anatop-vol-bit-width property set\n"); 151 goto anatop_probe_end; 152 } 153 ret = of_property_read_u32(np, "anatop-vol-bit-shift", 154 &sreg->vol_bit_shift); 155 if (ret) { 156 dev_err(dev, "no anatop-vol-bit-shift property set\n"); 157 goto anatop_probe_end; 158 } 159 ret = of_property_read_u32(np, "anatop-min-bit-val", 160 &sreg->min_bit_val); 161 if (ret) { 162 dev_err(dev, "no anatop-min-bit-val property set\n"); 163 goto anatop_probe_end; 164 } 165 ret = of_property_read_u32(np, "anatop-min-voltage", 166 &sreg->min_voltage); 167 if (ret) { 168 dev_err(dev, "no anatop-min-voltage property set\n"); 169 goto anatop_probe_end; 170 } 171 ret = of_property_read_u32(np, "anatop-max-voltage", 172 &sreg->max_voltage); 173 if (ret) { 174 dev_err(dev, "no anatop-max-voltage property set\n"); 175 goto anatop_probe_end; 176 } 177 178 rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) 179 / 25000 + 1; 180 181 /* register regulator */ 182 rdev = regulator_register(rdesc, dev, 183 initdata, sreg, pdev->dev.of_node); 184 if (IS_ERR(rdev)) { 185 dev_err(dev, "failed to register %s\n", 186 rdesc->name); 187 ret = PTR_ERR(rdev); 188 goto anatop_probe_end; 189 } 190 191 platform_set_drvdata(pdev, rdev); 192 193 anatop_probe_end: 194 if (ret) 195 kfree(sreg->name); 196 197 return ret; 198 } 199 200 static int __devexit anatop_regulator_remove(struct platform_device *pdev) 201 { 202 struct regulator_dev *rdev = platform_get_drvdata(pdev); 203 struct anatop_regulator *sreg = rdev_get_drvdata(rdev); 204 const char *name = sreg->name; 205 206 regulator_unregister(rdev); 207 kfree(name); 208 209 return 0; 210 } 211 212 static struct of_device_id __devinitdata of_anatop_regulator_match_tbl[] = { 213 { .compatible = "fsl,anatop-regulator", }, 214 { /* end */ } 215 }; 216 217 static struct platform_driver anatop_regulator_driver = { 218 .driver = { 219 .name = "anatop_regulator", 220 .owner = THIS_MODULE, 221 .of_match_table = of_anatop_regulator_match_tbl, 222 }, 223 .probe = anatop_regulator_probe, 224 .remove = anatop_regulator_remove, 225 }; 226 227 static int __init anatop_regulator_init(void) 228 { 229 return platform_driver_register(&anatop_regulator_driver); 230 } 231 postcore_initcall(anatop_regulator_init); 232 233 static void __exit anatop_regulator_exit(void) 234 { 235 platform_driver_unregister(&anatop_regulator_driver); 236 } 237 module_exit(anatop_regulator_exit); 238 239 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>, " 240 "Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>"); 241 MODULE_DESCRIPTION("ANATOP Regulator driver"); 242 MODULE_LICENSE("GPL v2"); 243