1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2016 MediaTek Inc. 4 * Author: Zhiyong Tao <zhiyong.tao@mediatek.com> 5 */ 6 7 #include <linux/clk.h> 8 #include <linux/delay.h> 9 #include <linux/err.h> 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/mod_devicetable.h> 13 #include <linux/platform_device.h> 14 #include <linux/property.h> 15 #include <linux/iopoll.h> 16 #include <linux/io.h> 17 #include <linux/iio/iio.h> 18 19 /* Register definitions */ 20 #define MT6577_AUXADC_CON0 0x00 21 #define MT6577_AUXADC_CON1 0x04 22 #define MT6577_AUXADC_CON2 0x10 23 #define MT6577_AUXADC_STA BIT(0) 24 25 #define MT6577_AUXADC_DAT0 0x14 26 #define MT6577_AUXADC_RDY0 BIT(12) 27 28 #define MT6577_AUXADC_MISC 0x94 29 #define MT6577_AUXADC_PDN_EN BIT(14) 30 31 #define MT6577_AUXADC_DAT_MASK 0xfff 32 #define MT6577_AUXADC_SLEEP_US 1000 33 #define MT6577_AUXADC_TIMEOUT_US 10000 34 #define MT6577_AUXADC_POWER_READY_MS 1 35 #define MT6577_AUXADC_SAMPLE_READY_US 25 36 37 struct mtk_auxadc_compatible { 38 bool sample_data_cali; 39 bool check_global_idle; 40 }; 41 42 struct mt6577_auxadc_device { 43 void __iomem *reg_base; 44 struct clk *adc_clk; 45 struct mutex lock; 46 const struct mtk_auxadc_compatible *dev_comp; 47 }; 48 49 static const struct mtk_auxadc_compatible mt8186_compat = { 50 .sample_data_cali = false, 51 .check_global_idle = false, 52 }; 53 54 static const struct mtk_auxadc_compatible mt8173_compat = { 55 .sample_data_cali = false, 56 .check_global_idle = true, 57 }; 58 59 static const struct mtk_auxadc_compatible mt6765_compat = { 60 .sample_data_cali = true, 61 .check_global_idle = false, 62 }; 63 64 #define MT6577_AUXADC_CHANNEL(idx) { \ 65 .type = IIO_VOLTAGE, \ 66 .indexed = 1, \ 67 .channel = (idx), \ 68 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ 69 } 70 71 static const struct iio_chan_spec mt6577_auxadc_iio_channels[] = { 72 MT6577_AUXADC_CHANNEL(0), 73 MT6577_AUXADC_CHANNEL(1), 74 MT6577_AUXADC_CHANNEL(2), 75 MT6577_AUXADC_CHANNEL(3), 76 MT6577_AUXADC_CHANNEL(4), 77 MT6577_AUXADC_CHANNEL(5), 78 MT6577_AUXADC_CHANNEL(6), 79 MT6577_AUXADC_CHANNEL(7), 80 MT6577_AUXADC_CHANNEL(8), 81 MT6577_AUXADC_CHANNEL(9), 82 MT6577_AUXADC_CHANNEL(10), 83 MT6577_AUXADC_CHANNEL(11), 84 MT6577_AUXADC_CHANNEL(12), 85 MT6577_AUXADC_CHANNEL(13), 86 MT6577_AUXADC_CHANNEL(14), 87 MT6577_AUXADC_CHANNEL(15), 88 }; 89 90 /* For Voltage calculation */ 91 #define VOLTAGE_FULL_RANGE 1500 /* VA voltage */ 92 #define AUXADC_PRECISE 4096 /* 12 bits */ 93 94 static int mt_auxadc_get_cali_data(int rawdata, bool enable_cali) 95 { 96 return rawdata; 97 } 98 99 static inline void mt6577_auxadc_mod_reg(void __iomem *reg, 100 u32 or_mask, u32 and_mask) 101 { 102 u32 val; 103 104 val = readl(reg); 105 val |= or_mask; 106 val &= ~and_mask; 107 writel(val, reg); 108 } 109 110 static int mt6577_auxadc_read(struct iio_dev *indio_dev, 111 struct iio_chan_spec const *chan) 112 { 113 u32 val; 114 void __iomem *reg_channel; 115 int ret; 116 struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev); 117 118 reg_channel = adc_dev->reg_base + MT6577_AUXADC_DAT0 + 119 chan->channel * 0x04; 120 121 mutex_lock(&adc_dev->lock); 122 123 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_CON1, 124 0, 1 << chan->channel); 125 126 /* read channel and make sure old ready bit == 0 */ 127 ret = readl_poll_timeout(reg_channel, val, 128 ((val & MT6577_AUXADC_RDY0) == 0), 129 MT6577_AUXADC_SLEEP_US, 130 MT6577_AUXADC_TIMEOUT_US); 131 if (ret < 0) { 132 dev_err(indio_dev->dev.parent, 133 "wait for channel[%d] ready bit clear time out\n", 134 chan->channel); 135 goto err_timeout; 136 } 137 138 /* set bit to trigger sample */ 139 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_CON1, 140 1 << chan->channel, 0); 141 142 /* we must delay here for hardware sample channel data */ 143 udelay(MT6577_AUXADC_SAMPLE_READY_US); 144 145 if (adc_dev->dev_comp->check_global_idle) { 146 /* check MTK_AUXADC_CON2 if auxadc is idle */ 147 ret = readl_poll_timeout(adc_dev->reg_base + MT6577_AUXADC_CON2, 148 val, ((val & MT6577_AUXADC_STA) == 0), 149 MT6577_AUXADC_SLEEP_US, 150 MT6577_AUXADC_TIMEOUT_US); 151 if (ret < 0) { 152 dev_err(indio_dev->dev.parent, 153 "wait for auxadc idle time out\n"); 154 goto err_timeout; 155 } 156 } 157 158 /* read channel and make sure ready bit == 1 */ 159 ret = readl_poll_timeout(reg_channel, val, 160 ((val & MT6577_AUXADC_RDY0) != 0), 161 MT6577_AUXADC_SLEEP_US, 162 MT6577_AUXADC_TIMEOUT_US); 163 if (ret < 0) { 164 dev_err(indio_dev->dev.parent, 165 "wait for channel[%d] data ready time out\n", 166 chan->channel); 167 goto err_timeout; 168 } 169 170 /* read data */ 171 val = readl(reg_channel) & MT6577_AUXADC_DAT_MASK; 172 173 mutex_unlock(&adc_dev->lock); 174 175 return val; 176 177 err_timeout: 178 179 mutex_unlock(&adc_dev->lock); 180 181 return -ETIMEDOUT; 182 } 183 184 static int mt6577_auxadc_read_raw(struct iio_dev *indio_dev, 185 struct iio_chan_spec const *chan, 186 int *val, 187 int *val2, 188 long info) 189 { 190 struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev); 191 192 switch (info) { 193 case IIO_CHAN_INFO_PROCESSED: 194 *val = mt6577_auxadc_read(indio_dev, chan); 195 if (*val < 0) { 196 dev_err(indio_dev->dev.parent, 197 "failed to sample data on channel[%d]\n", 198 chan->channel); 199 return *val; 200 } 201 if (adc_dev->dev_comp->sample_data_cali) 202 *val = mt_auxadc_get_cali_data(*val, true); 203 204 /* Convert adc raw data to voltage: 0 - 1500 mV */ 205 *val = *val * VOLTAGE_FULL_RANGE / AUXADC_PRECISE; 206 207 return IIO_VAL_INT; 208 209 default: 210 return -EINVAL; 211 } 212 } 213 214 static const struct iio_info mt6577_auxadc_info = { 215 .read_raw = &mt6577_auxadc_read_raw, 216 }; 217 218 static int __maybe_unused mt6577_auxadc_resume(struct device *dev) 219 { 220 struct iio_dev *indio_dev = dev_get_drvdata(dev); 221 struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev); 222 int ret; 223 224 ret = clk_prepare_enable(adc_dev->adc_clk); 225 if (ret) { 226 pr_err("failed to enable auxadc clock\n"); 227 return ret; 228 } 229 230 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC, 231 MT6577_AUXADC_PDN_EN, 0); 232 mdelay(MT6577_AUXADC_POWER_READY_MS); 233 234 return 0; 235 } 236 237 static int __maybe_unused mt6577_auxadc_suspend(struct device *dev) 238 { 239 struct iio_dev *indio_dev = dev_get_drvdata(dev); 240 struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev); 241 242 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC, 243 0, MT6577_AUXADC_PDN_EN); 244 clk_disable_unprepare(adc_dev->adc_clk); 245 246 return 0; 247 } 248 249 static int mt6577_auxadc_probe(struct platform_device *pdev) 250 { 251 struct mt6577_auxadc_device *adc_dev; 252 unsigned long adc_clk_rate; 253 struct iio_dev *indio_dev; 254 int ret; 255 256 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc_dev)); 257 if (!indio_dev) 258 return -ENOMEM; 259 260 adc_dev = iio_priv(indio_dev); 261 indio_dev->name = dev_name(&pdev->dev); 262 indio_dev->info = &mt6577_auxadc_info; 263 indio_dev->modes = INDIO_DIRECT_MODE; 264 indio_dev->channels = mt6577_auxadc_iio_channels; 265 indio_dev->num_channels = ARRAY_SIZE(mt6577_auxadc_iio_channels); 266 267 adc_dev->reg_base = devm_platform_ioremap_resource(pdev, 0); 268 if (IS_ERR(adc_dev->reg_base)) { 269 dev_err(&pdev->dev, "failed to get auxadc base address\n"); 270 return PTR_ERR(adc_dev->reg_base); 271 } 272 273 adc_dev->adc_clk = devm_clk_get(&pdev->dev, "main"); 274 if (IS_ERR(adc_dev->adc_clk)) { 275 dev_err(&pdev->dev, "failed to get auxadc clock\n"); 276 return PTR_ERR(adc_dev->adc_clk); 277 } 278 279 ret = clk_prepare_enable(adc_dev->adc_clk); 280 if (ret) { 281 dev_err(&pdev->dev, "failed to enable auxadc clock\n"); 282 return ret; 283 } 284 285 adc_clk_rate = clk_get_rate(adc_dev->adc_clk); 286 if (!adc_clk_rate) { 287 ret = -EINVAL; 288 dev_err(&pdev->dev, "null clock rate\n"); 289 goto err_disable_clk; 290 } 291 292 adc_dev->dev_comp = device_get_match_data(&pdev->dev); 293 294 mutex_init(&adc_dev->lock); 295 296 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC, 297 MT6577_AUXADC_PDN_EN, 0); 298 mdelay(MT6577_AUXADC_POWER_READY_MS); 299 300 platform_set_drvdata(pdev, indio_dev); 301 302 ret = iio_device_register(indio_dev); 303 if (ret < 0) { 304 dev_err(&pdev->dev, "failed to register iio device\n"); 305 goto err_power_off; 306 } 307 308 return 0; 309 310 err_power_off: 311 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC, 312 0, MT6577_AUXADC_PDN_EN); 313 err_disable_clk: 314 clk_disable_unprepare(adc_dev->adc_clk); 315 return ret; 316 } 317 318 static int mt6577_auxadc_remove(struct platform_device *pdev) 319 { 320 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 321 struct mt6577_auxadc_device *adc_dev = iio_priv(indio_dev); 322 323 iio_device_unregister(indio_dev); 324 325 mt6577_auxadc_mod_reg(adc_dev->reg_base + MT6577_AUXADC_MISC, 326 0, MT6577_AUXADC_PDN_EN); 327 328 clk_disable_unprepare(adc_dev->adc_clk); 329 330 return 0; 331 } 332 333 static SIMPLE_DEV_PM_OPS(mt6577_auxadc_pm_ops, 334 mt6577_auxadc_suspend, 335 mt6577_auxadc_resume); 336 337 static const struct of_device_id mt6577_auxadc_of_match[] = { 338 { .compatible = "mediatek,mt2701-auxadc", .data = &mt8173_compat }, 339 { .compatible = "mediatek,mt2712-auxadc", .data = &mt8173_compat }, 340 { .compatible = "mediatek,mt7622-auxadc", .data = &mt8173_compat }, 341 { .compatible = "mediatek,mt8173-auxadc", .data = &mt8173_compat }, 342 { .compatible = "mediatek,mt8186-auxadc", .data = &mt8186_compat }, 343 { .compatible = "mediatek,mt6765-auxadc", .data = &mt6765_compat }, 344 { } 345 }; 346 MODULE_DEVICE_TABLE(of, mt6577_auxadc_of_match); 347 348 static struct platform_driver mt6577_auxadc_driver = { 349 .driver = { 350 .name = "mt6577-auxadc", 351 .of_match_table = mt6577_auxadc_of_match, 352 .pm = &mt6577_auxadc_pm_ops, 353 }, 354 .probe = mt6577_auxadc_probe, 355 .remove = mt6577_auxadc_remove, 356 }; 357 module_platform_driver(mt6577_auxadc_driver); 358 359 MODULE_AUTHOR("Zhiyong Tao <zhiyong.tao@mediatek.com>"); 360 MODULE_DESCRIPTION("MTK AUXADC Device Driver"); 361 MODULE_LICENSE("GPL v2"); 362