1 /* 2 * Amlogic Meson Successive Approximation Register (SAR) A/D Converter 3 * 4 * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com> 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 version 2 as 8 * published by the Free Software Foundation. 9 * 10 * You should have received a copy of the GNU General Public License 11 * along with this program. If not, see <http://www.gnu.org/licenses/>. 12 */ 13 14 #include <linux/bitfield.h> 15 #include <linux/clk.h> 16 #include <linux/clk-provider.h> 17 #include <linux/delay.h> 18 #include <linux/io.h> 19 #include <linux/iio/iio.h> 20 #include <linux/module.h> 21 #include <linux/interrupt.h> 22 #include <linux/of.h> 23 #include <linux/of_irq.h> 24 #include <linux/of_device.h> 25 #include <linux/platform_device.h> 26 #include <linux/regmap.h> 27 #include <linux/regulator/consumer.h> 28 29 #define MESON_SAR_ADC_REG0 0x00 30 #define MESON_SAR_ADC_REG0_PANEL_DETECT BIT(31) 31 #define MESON_SAR_ADC_REG0_BUSY_MASK GENMASK(30, 28) 32 #define MESON_SAR_ADC_REG0_DELTA_BUSY BIT(30) 33 #define MESON_SAR_ADC_REG0_AVG_BUSY BIT(29) 34 #define MESON_SAR_ADC_REG0_SAMPLE_BUSY BIT(28) 35 #define MESON_SAR_ADC_REG0_FIFO_FULL BIT(27) 36 #define MESON_SAR_ADC_REG0_FIFO_EMPTY BIT(26) 37 #define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK GENMASK(25, 21) 38 #define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK GENMASK(20, 19) 39 #define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK GENMASK(18, 16) 40 #define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL BIT(15) 41 #define MESON_SAR_ADC_REG0_SAMPLING_STOP BIT(14) 42 #define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK GENMASK(13, 12) 43 #define MESON_SAR_ADC_REG0_DETECT_IRQ_POL BIT(10) 44 #define MESON_SAR_ADC_REG0_DETECT_IRQ_EN BIT(9) 45 #define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK GENMASK(8, 4) 46 #define MESON_SAR_ADC_REG0_FIFO_IRQ_EN BIT(3) 47 #define MESON_SAR_ADC_REG0_SAMPLING_START BIT(2) 48 #define MESON_SAR_ADC_REG0_CONTINUOUS_EN BIT(1) 49 #define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE BIT(0) 50 51 #define MESON_SAR_ADC_CHAN_LIST 0x04 52 #define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK GENMASK(26, 24) 53 #define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan) \ 54 (GENMASK(2, 0) << ((_chan) * 3)) 55 56 #define MESON_SAR_ADC_AVG_CNTL 0x08 57 #define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan) \ 58 (16 + ((_chan) * 2)) 59 #define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan) \ 60 (GENMASK(17, 16) << ((_chan) * 2)) 61 #define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan) \ 62 (0 + ((_chan) * 2)) 63 #define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan) \ 64 (GENMASK(1, 0) << ((_chan) * 2)) 65 66 #define MESON_SAR_ADC_REG3 0x0c 67 #define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY BIT(31) 68 #define MESON_SAR_ADC_REG3_CLK_EN BIT(30) 69 #define MESON_SAR_ADC_REG3_BL30_INITIALIZED BIT(28) 70 #define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN BIT(27) 71 #define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE BIT(26) 72 #define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK GENMASK(25, 23) 73 #define MESON_SAR_ADC_REG3_DETECT_EN BIT(22) 74 #define MESON_SAR_ADC_REG3_ADC_EN BIT(21) 75 #define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK GENMASK(20, 18) 76 #define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK GENMASK(17, 16) 77 #define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT 10 78 #define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH 5 79 #define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK GENMASK(9, 8) 80 #define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK GENMASK(7, 0) 81 82 #define MESON_SAR_ADC_DELAY 0x10 83 #define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK GENMASK(25, 24) 84 #define MESON_SAR_ADC_DELAY_BL30_BUSY BIT(15) 85 #define MESON_SAR_ADC_DELAY_KERNEL_BUSY BIT(14) 86 #define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK GENMASK(23, 16) 87 #define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK GENMASK(9, 8) 88 #define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK GENMASK(7, 0) 89 90 #define MESON_SAR_ADC_LAST_RD 0x14 91 #define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK GENMASK(23, 16) 92 #define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK GENMASK(9, 0) 93 94 #define MESON_SAR_ADC_FIFO_RD 0x18 95 #define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK GENMASK(14, 12) 96 #define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK GENMASK(11, 0) 97 98 #define MESON_SAR_ADC_AUX_SW 0x1c 99 #define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_MASK(_chan) \ 100 (GENMASK(10, 8) << (((_chan) - 2) * 2)) 101 #define MESON_SAR_ADC_AUX_SW_VREF_P_MUX BIT(6) 102 #define MESON_SAR_ADC_AUX_SW_VREF_N_MUX BIT(5) 103 #define MESON_SAR_ADC_AUX_SW_MODE_SEL BIT(4) 104 #define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW BIT(3) 105 #define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW BIT(2) 106 #define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW BIT(1) 107 #define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW BIT(0) 108 109 #define MESON_SAR_ADC_CHAN_10_SW 0x20 110 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK GENMASK(25, 23) 111 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX BIT(22) 112 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX BIT(21) 113 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL BIT(20) 114 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW BIT(19) 115 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW BIT(18) 116 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW BIT(17) 117 #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW BIT(16) 118 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK GENMASK(9, 7) 119 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX BIT(6) 120 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX BIT(5) 121 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL BIT(4) 122 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW BIT(3) 123 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW BIT(2) 124 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW BIT(1) 125 #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW BIT(0) 126 127 #define MESON_SAR_ADC_DETECT_IDLE_SW 0x24 128 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN BIT(26) 129 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK GENMASK(25, 23) 130 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX BIT(22) 131 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX BIT(21) 132 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL BIT(20) 133 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW BIT(19) 134 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW BIT(18) 135 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW BIT(17) 136 #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW BIT(16) 137 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK GENMASK(9, 7) 138 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX BIT(6) 139 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX BIT(5) 140 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL BIT(4) 141 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW BIT(3) 142 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW BIT(2) 143 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW BIT(1) 144 #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW BIT(0) 145 146 #define MESON_SAR_ADC_DELTA_10 0x28 147 #define MESON_SAR_ADC_DELTA_10_TEMP_SEL BIT(27) 148 #define MESON_SAR_ADC_DELTA_10_TS_REVE1 BIT(26) 149 #define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK GENMASK(25, 16) 150 #define MESON_SAR_ADC_DELTA_10_TS_REVE0 BIT(15) 151 #define MESON_SAR_ADC_DELTA_10_TS_C_SHIFT 11 152 #define MESON_SAR_ADC_DELTA_10_TS_C_MASK GENMASK(14, 11) 153 #define MESON_SAR_ADC_DELTA_10_TS_VBG_EN BIT(10) 154 #define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK GENMASK(9, 0) 155 156 /* 157 * NOTE: registers from here are undocumented (the vendor Linux kernel driver 158 * and u-boot source served as reference). These only seem to be relevant on 159 * GXBB and newer. 160 */ 161 #define MESON_SAR_ADC_REG11 0x2c 162 #define MESON_SAR_ADC_REG11_BANDGAP_EN BIT(13) 163 164 #define MESON_SAR_ADC_REG13 0x34 165 #define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK GENMASK(13, 8) 166 167 #define MESON_SAR_ADC_MAX_FIFO_SIZE 32 168 #define MESON_SAR_ADC_TIMEOUT 100 /* ms */ 169 /* for use with IIO_VAL_INT_PLUS_MICRO */ 170 #define MILLION 1000000 171 172 #define MESON_SAR_ADC_CHAN(_chan) { \ 173 .type = IIO_VOLTAGE, \ 174 .indexed = 1, \ 175 .channel = _chan, \ 176 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 177 BIT(IIO_CHAN_INFO_AVERAGE_RAW), \ 178 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 179 BIT(IIO_CHAN_INFO_CALIBBIAS) | \ 180 BIT(IIO_CHAN_INFO_CALIBSCALE), \ 181 .datasheet_name = "SAR_ADC_CH"#_chan, \ 182 } 183 184 /* 185 * TODO: the hardware supports IIO_TEMP for channel 6 as well which is 186 * currently not supported by this driver. 187 */ 188 static const struct iio_chan_spec meson_sar_adc_iio_channels[] = { 189 MESON_SAR_ADC_CHAN(0), 190 MESON_SAR_ADC_CHAN(1), 191 MESON_SAR_ADC_CHAN(2), 192 MESON_SAR_ADC_CHAN(3), 193 MESON_SAR_ADC_CHAN(4), 194 MESON_SAR_ADC_CHAN(5), 195 MESON_SAR_ADC_CHAN(6), 196 MESON_SAR_ADC_CHAN(7), 197 IIO_CHAN_SOFT_TIMESTAMP(8), 198 }; 199 200 enum meson_sar_adc_avg_mode { 201 NO_AVERAGING = 0x0, 202 MEAN_AVERAGING = 0x1, 203 MEDIAN_AVERAGING = 0x2, 204 }; 205 206 enum meson_sar_adc_num_samples { 207 ONE_SAMPLE = 0x0, 208 TWO_SAMPLES = 0x1, 209 FOUR_SAMPLES = 0x2, 210 EIGHT_SAMPLES = 0x3, 211 }; 212 213 enum meson_sar_adc_chan7_mux_sel { 214 CHAN7_MUX_VSS = 0x0, 215 CHAN7_MUX_VDD_DIV4 = 0x1, 216 CHAN7_MUX_VDD_DIV2 = 0x2, 217 CHAN7_MUX_VDD_MUL3_DIV4 = 0x3, 218 CHAN7_MUX_VDD = 0x4, 219 CHAN7_MUX_CH7_INPUT = 0x7, 220 }; 221 222 struct meson_sar_adc_data { 223 bool has_bl30_integration; 224 u32 bandgap_reg; 225 unsigned int resolution; 226 const char *name; 227 const struct regmap_config *regmap_config; 228 }; 229 230 struct meson_sar_adc_priv { 231 struct regmap *regmap; 232 struct regulator *vref; 233 const struct meson_sar_adc_data *data; 234 struct clk *clkin; 235 struct clk *core_clk; 236 struct clk *sana_clk; 237 struct clk *adc_sel_clk; 238 struct clk *adc_clk; 239 struct clk_gate clk_gate; 240 struct clk *adc_div_clk; 241 struct clk_divider clk_div; 242 struct completion done; 243 int calibbias; 244 int calibscale; 245 }; 246 247 static const struct regmap_config meson_sar_adc_regmap_config_gxbb = { 248 .reg_bits = 8, 249 .val_bits = 32, 250 .reg_stride = 4, 251 .max_register = MESON_SAR_ADC_REG13, 252 }; 253 254 static const struct regmap_config meson_sar_adc_regmap_config_meson8 = { 255 .reg_bits = 8, 256 .val_bits = 32, 257 .reg_stride = 4, 258 .max_register = MESON_SAR_ADC_DELTA_10, 259 }; 260 261 static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev) 262 { 263 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 264 u32 regval; 265 266 regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); 267 268 return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval); 269 } 270 271 static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val) 272 { 273 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 274 int tmp; 275 276 /* use val_calib = scale * val_raw + offset calibration function */ 277 tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias; 278 279 return clamp(tmp, 0, (1 << priv->data->resolution) - 1); 280 } 281 282 static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev) 283 { 284 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 285 int regval, timeout = 10000; 286 287 /* 288 * NOTE: we need a small delay before reading the status, otherwise 289 * the sample engine may not have started internally (which would 290 * seem to us that sampling is already finished). 291 */ 292 do { 293 udelay(1); 294 regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); 295 } while (FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, regval) && timeout--); 296 297 if (timeout < 0) 298 return -ETIMEDOUT; 299 300 return 0; 301 } 302 303 static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev, 304 const struct iio_chan_spec *chan, 305 int *val) 306 { 307 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 308 int regval, fifo_chan, fifo_val, count; 309 310 if(!wait_for_completion_timeout(&priv->done, 311 msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT))) 312 return -ETIMEDOUT; 313 314 count = meson_sar_adc_get_fifo_count(indio_dev); 315 if (count != 1) { 316 dev_err(&indio_dev->dev, 317 "ADC FIFO has %d element(s) instead of one\n", count); 318 return -EINVAL; 319 } 320 321 regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, ®val); 322 fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval); 323 if (fifo_chan != chan->channel) { 324 dev_err(&indio_dev->dev, 325 "ADC FIFO entry belongs to channel %d instead of %d\n", 326 fifo_chan, chan->channel); 327 return -EINVAL; 328 } 329 330 fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval); 331 fifo_val &= GENMASK(priv->data->resolution - 1, 0); 332 *val = meson_sar_adc_calib_val(indio_dev, fifo_val); 333 334 return 0; 335 } 336 337 static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev, 338 const struct iio_chan_spec *chan, 339 enum meson_sar_adc_avg_mode mode, 340 enum meson_sar_adc_num_samples samples) 341 { 342 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 343 int val, channel = chan->channel; 344 345 val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(channel); 346 regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL, 347 MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(channel), 348 val); 349 350 val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(channel); 351 regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL, 352 MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(channel), val); 353 } 354 355 static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev, 356 const struct iio_chan_spec *chan) 357 { 358 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 359 u32 regval; 360 361 /* 362 * the SAR ADC engine allows sampling multiple channels at the same 363 * time. to keep it simple we're only working with one *internal* 364 * channel, which starts counting at index 0 (which means: count = 1). 365 */ 366 regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0); 367 regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 368 MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval); 369 370 /* map channel index 0 to the channel which we want to read */ 371 regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), 372 chan->channel); 373 regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 374 MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval); 375 376 regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK, 377 chan->channel); 378 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW, 379 MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK, 380 regval); 381 382 regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK, 383 chan->channel); 384 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW, 385 MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK, 386 regval); 387 388 if (chan->channel == 6) 389 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10, 390 MESON_SAR_ADC_DELTA_10_TEMP_SEL, 0); 391 } 392 393 static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev, 394 enum meson_sar_adc_chan7_mux_sel sel) 395 { 396 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 397 u32 regval; 398 399 regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel); 400 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 401 MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval); 402 403 usleep_range(10, 20); 404 } 405 406 static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev) 407 { 408 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 409 410 reinit_completion(&priv->done); 411 412 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 413 MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 414 MESON_SAR_ADC_REG0_FIFO_IRQ_EN); 415 416 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 417 MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 418 MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE); 419 420 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 421 MESON_SAR_ADC_REG0_SAMPLING_START, 422 MESON_SAR_ADC_REG0_SAMPLING_START); 423 } 424 425 static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev) 426 { 427 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 428 429 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 430 MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0); 431 432 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 433 MESON_SAR_ADC_REG0_SAMPLING_STOP, 434 MESON_SAR_ADC_REG0_SAMPLING_STOP); 435 436 /* wait until all modules are stopped */ 437 meson_sar_adc_wait_busy_clear(indio_dev); 438 439 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 440 MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0); 441 } 442 443 static int meson_sar_adc_lock(struct iio_dev *indio_dev) 444 { 445 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 446 int val, timeout = 10000; 447 448 mutex_lock(&indio_dev->mlock); 449 450 if (priv->data->has_bl30_integration) { 451 /* prevent BL30 from using the SAR ADC while we are using it */ 452 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 453 MESON_SAR_ADC_DELAY_KERNEL_BUSY, 454 MESON_SAR_ADC_DELAY_KERNEL_BUSY); 455 456 /* 457 * wait until BL30 releases it's lock (so we can use the SAR 458 * ADC) 459 */ 460 do { 461 udelay(1); 462 regmap_read(priv->regmap, MESON_SAR_ADC_DELAY, &val); 463 } while (val & MESON_SAR_ADC_DELAY_BL30_BUSY && timeout--); 464 465 if (timeout < 0) 466 return -ETIMEDOUT; 467 } 468 469 return 0; 470 } 471 472 static void meson_sar_adc_unlock(struct iio_dev *indio_dev) 473 { 474 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 475 476 if (priv->data->has_bl30_integration) 477 /* allow BL30 to use the SAR ADC again */ 478 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 479 MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0); 480 481 mutex_unlock(&indio_dev->mlock); 482 } 483 484 static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev) 485 { 486 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 487 unsigned int count, tmp; 488 489 for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) { 490 if (!meson_sar_adc_get_fifo_count(indio_dev)) 491 break; 492 493 regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp); 494 } 495 } 496 497 static int meson_sar_adc_get_sample(struct iio_dev *indio_dev, 498 const struct iio_chan_spec *chan, 499 enum meson_sar_adc_avg_mode avg_mode, 500 enum meson_sar_adc_num_samples avg_samples, 501 int *val) 502 { 503 int ret; 504 505 ret = meson_sar_adc_lock(indio_dev); 506 if (ret) 507 return ret; 508 509 /* clear the FIFO to make sure we're not reading old values */ 510 meson_sar_adc_clear_fifo(indio_dev); 511 512 meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples); 513 514 meson_sar_adc_enable_channel(indio_dev, chan); 515 516 meson_sar_adc_start_sample_engine(indio_dev); 517 ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val); 518 meson_sar_adc_stop_sample_engine(indio_dev); 519 520 meson_sar_adc_unlock(indio_dev); 521 522 if (ret) { 523 dev_warn(indio_dev->dev.parent, 524 "failed to read sample for channel %d: %d\n", 525 chan->channel, ret); 526 return ret; 527 } 528 529 return IIO_VAL_INT; 530 } 531 532 static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev, 533 const struct iio_chan_spec *chan, 534 int *val, int *val2, long mask) 535 { 536 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 537 int ret; 538 539 switch (mask) { 540 case IIO_CHAN_INFO_RAW: 541 return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING, 542 ONE_SAMPLE, val); 543 break; 544 545 case IIO_CHAN_INFO_AVERAGE_RAW: 546 return meson_sar_adc_get_sample(indio_dev, chan, 547 MEAN_AVERAGING, EIGHT_SAMPLES, 548 val); 549 break; 550 551 case IIO_CHAN_INFO_SCALE: 552 ret = regulator_get_voltage(priv->vref); 553 if (ret < 0) { 554 dev_err(indio_dev->dev.parent, 555 "failed to get vref voltage: %d\n", ret); 556 return ret; 557 } 558 559 *val = ret / 1000; 560 *val2 = priv->data->resolution; 561 return IIO_VAL_FRACTIONAL_LOG2; 562 563 case IIO_CHAN_INFO_CALIBBIAS: 564 *val = priv->calibbias; 565 return IIO_VAL_INT; 566 567 case IIO_CHAN_INFO_CALIBSCALE: 568 *val = priv->calibscale / MILLION; 569 *val2 = priv->calibscale % MILLION; 570 return IIO_VAL_INT_PLUS_MICRO; 571 572 default: 573 return -EINVAL; 574 } 575 } 576 577 static int meson_sar_adc_clk_init(struct iio_dev *indio_dev, 578 void __iomem *base) 579 { 580 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 581 struct clk_init_data init; 582 const char *clk_parents[1]; 583 584 init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%pOF#adc_div", 585 indio_dev->dev.of_node); 586 init.flags = 0; 587 init.ops = &clk_divider_ops; 588 clk_parents[0] = __clk_get_name(priv->clkin); 589 init.parent_names = clk_parents; 590 init.num_parents = 1; 591 592 priv->clk_div.reg = base + MESON_SAR_ADC_REG3; 593 priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT; 594 priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH; 595 priv->clk_div.hw.init = &init; 596 priv->clk_div.flags = 0; 597 598 priv->adc_div_clk = devm_clk_register(&indio_dev->dev, 599 &priv->clk_div.hw); 600 if (WARN_ON(IS_ERR(priv->adc_div_clk))) 601 return PTR_ERR(priv->adc_div_clk); 602 603 init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%pOF#adc_en", 604 indio_dev->dev.of_node); 605 init.flags = CLK_SET_RATE_PARENT; 606 init.ops = &clk_gate_ops; 607 clk_parents[0] = __clk_get_name(priv->adc_div_clk); 608 init.parent_names = clk_parents; 609 init.num_parents = 1; 610 611 priv->clk_gate.reg = base + MESON_SAR_ADC_REG3; 612 priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN); 613 priv->clk_gate.hw.init = &init; 614 615 priv->adc_clk = devm_clk_register(&indio_dev->dev, &priv->clk_gate.hw); 616 if (WARN_ON(IS_ERR(priv->adc_clk))) 617 return PTR_ERR(priv->adc_clk); 618 619 return 0; 620 } 621 622 static int meson_sar_adc_init(struct iio_dev *indio_dev) 623 { 624 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 625 int regval, ret; 626 627 /* 628 * make sure we start at CH7 input since the other muxes are only used 629 * for internal calibration. 630 */ 631 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT); 632 633 if (priv->data->has_bl30_integration) { 634 /* 635 * leave sampling delay and the input clocks as configured by 636 * BL30 to make sure BL30 gets the values it expects when 637 * reading the temperature sensor. 638 */ 639 regmap_read(priv->regmap, MESON_SAR_ADC_REG3, ®val); 640 if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED) 641 return 0; 642 } 643 644 meson_sar_adc_stop_sample_engine(indio_dev); 645 646 /* update the channel 6 MUX to select the temperature sensor */ 647 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 648 MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 649 MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL); 650 651 /* disable all channels by default */ 652 regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0); 653 654 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 655 MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0); 656 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 657 MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY, 658 MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY); 659 660 /* delay between two samples = (10+1) * 1uS */ 661 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 662 MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK, 663 FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK, 664 10)); 665 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 666 MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK, 667 FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK, 668 0)); 669 670 /* delay between two samples = (10+1) * 1uS */ 671 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 672 MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK, 673 FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK, 674 10)); 675 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 676 MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK, 677 FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK, 678 1)); 679 680 ret = clk_set_parent(priv->adc_sel_clk, priv->clkin); 681 if (ret) { 682 dev_err(indio_dev->dev.parent, 683 "failed to set adc parent to clkin\n"); 684 return ret; 685 } 686 687 ret = clk_set_rate(priv->adc_clk, 1200000); 688 if (ret) { 689 dev_err(indio_dev->dev.parent, 690 "failed to set adc clock rate\n"); 691 return ret; 692 } 693 694 return 0; 695 } 696 697 static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off) 698 { 699 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 700 u32 enable_mask; 701 702 if (priv->data->bandgap_reg == MESON_SAR_ADC_REG11) 703 enable_mask = MESON_SAR_ADC_REG11_BANDGAP_EN; 704 else 705 enable_mask = MESON_SAR_ADC_DELTA_10_TS_VBG_EN; 706 707 regmap_update_bits(priv->regmap, priv->data->bandgap_reg, enable_mask, 708 on_off ? enable_mask : 0); 709 } 710 711 static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev) 712 { 713 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 714 int ret; 715 u32 regval; 716 717 ret = meson_sar_adc_lock(indio_dev); 718 if (ret) 719 goto err_lock; 720 721 ret = regulator_enable(priv->vref); 722 if (ret < 0) { 723 dev_err(indio_dev->dev.parent, 724 "failed to enable vref regulator\n"); 725 goto err_vref; 726 } 727 728 ret = clk_prepare_enable(priv->core_clk); 729 if (ret) { 730 dev_err(indio_dev->dev.parent, "failed to enable core clk\n"); 731 goto err_core_clk; 732 } 733 734 ret = clk_prepare_enable(priv->sana_clk); 735 if (ret) { 736 dev_err(indio_dev->dev.parent, "failed to enable sana clk\n"); 737 goto err_sana_clk; 738 } 739 740 regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1); 741 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 742 MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval); 743 744 meson_sar_adc_set_bandgap(indio_dev, true); 745 746 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 747 MESON_SAR_ADC_REG3_ADC_EN, 748 MESON_SAR_ADC_REG3_ADC_EN); 749 750 udelay(5); 751 752 ret = clk_prepare_enable(priv->adc_clk); 753 if (ret) { 754 dev_err(indio_dev->dev.parent, "failed to enable adc clk\n"); 755 goto err_adc_clk; 756 } 757 758 meson_sar_adc_unlock(indio_dev); 759 760 return 0; 761 762 err_adc_clk: 763 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 764 MESON_SAR_ADC_REG3_ADC_EN, 0); 765 meson_sar_adc_set_bandgap(indio_dev, false); 766 clk_disable_unprepare(priv->sana_clk); 767 err_sana_clk: 768 clk_disable_unprepare(priv->core_clk); 769 err_core_clk: 770 regulator_disable(priv->vref); 771 err_vref: 772 meson_sar_adc_unlock(indio_dev); 773 err_lock: 774 return ret; 775 } 776 777 static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev) 778 { 779 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 780 int ret; 781 782 ret = meson_sar_adc_lock(indio_dev); 783 if (ret) 784 return ret; 785 786 clk_disable_unprepare(priv->adc_clk); 787 788 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 789 MESON_SAR_ADC_REG3_ADC_EN, 0); 790 791 meson_sar_adc_set_bandgap(indio_dev, false); 792 793 clk_disable_unprepare(priv->sana_clk); 794 clk_disable_unprepare(priv->core_clk); 795 796 regulator_disable(priv->vref); 797 798 meson_sar_adc_unlock(indio_dev); 799 800 return 0; 801 } 802 803 static irqreturn_t meson_sar_adc_irq(int irq, void *data) 804 { 805 struct iio_dev *indio_dev = data; 806 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 807 unsigned int cnt, threshold; 808 u32 regval; 809 810 regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); 811 cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval); 812 threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval); 813 814 if (cnt < threshold) 815 return IRQ_NONE; 816 817 complete(&priv->done); 818 819 return IRQ_HANDLED; 820 } 821 822 static int meson_sar_adc_calib(struct iio_dev *indio_dev) 823 { 824 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 825 int ret, nominal0, nominal1, value0, value1; 826 827 /* use points 25% and 75% for calibration */ 828 nominal0 = (1 << priv->data->resolution) / 4; 829 nominal1 = (1 << priv->data->resolution) * 3 / 4; 830 831 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4); 832 usleep_range(10, 20); 833 ret = meson_sar_adc_get_sample(indio_dev, 834 &meson_sar_adc_iio_channels[7], 835 MEAN_AVERAGING, EIGHT_SAMPLES, &value0); 836 if (ret < 0) 837 goto out; 838 839 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4); 840 usleep_range(10, 20); 841 ret = meson_sar_adc_get_sample(indio_dev, 842 &meson_sar_adc_iio_channels[7], 843 MEAN_AVERAGING, EIGHT_SAMPLES, &value1); 844 if (ret < 0) 845 goto out; 846 847 if (value1 <= value0) { 848 ret = -EINVAL; 849 goto out; 850 } 851 852 priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION, 853 value1 - value0); 854 priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale, 855 MILLION); 856 ret = 0; 857 out: 858 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT); 859 860 return ret; 861 } 862 863 static const struct iio_info meson_sar_adc_iio_info = { 864 .read_raw = meson_sar_adc_iio_info_read_raw, 865 }; 866 867 static const struct meson_sar_adc_data meson_sar_adc_meson8_data = { 868 .has_bl30_integration = false, 869 .bandgap_reg = MESON_SAR_ADC_DELTA_10, 870 .regmap_config = &meson_sar_adc_regmap_config_meson8, 871 .resolution = 10, 872 .name = "meson-meson8-saradc", 873 }; 874 875 static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = { 876 .has_bl30_integration = false, 877 .bandgap_reg = MESON_SAR_ADC_DELTA_10, 878 .regmap_config = &meson_sar_adc_regmap_config_meson8, 879 .resolution = 10, 880 .name = "meson-meson8b-saradc", 881 }; 882 883 static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = { 884 .has_bl30_integration = true, 885 .bandgap_reg = MESON_SAR_ADC_REG11, 886 .regmap_config = &meson_sar_adc_regmap_config_gxbb, 887 .resolution = 10, 888 .name = "meson-gxbb-saradc", 889 }; 890 891 static const struct meson_sar_adc_data meson_sar_adc_gxl_data = { 892 .has_bl30_integration = true, 893 .bandgap_reg = MESON_SAR_ADC_REG11, 894 .regmap_config = &meson_sar_adc_regmap_config_gxbb, 895 .resolution = 12, 896 .name = "meson-gxl-saradc", 897 }; 898 899 static const struct meson_sar_adc_data meson_sar_adc_gxm_data = { 900 .has_bl30_integration = true, 901 .bandgap_reg = MESON_SAR_ADC_REG11, 902 .regmap_config = &meson_sar_adc_regmap_config_gxbb, 903 .resolution = 12, 904 .name = "meson-gxm-saradc", 905 }; 906 907 static const struct of_device_id meson_sar_adc_of_match[] = { 908 { 909 .compatible = "amlogic,meson8-saradc", 910 .data = &meson_sar_adc_meson8_data, 911 }, 912 { 913 .compatible = "amlogic,meson8b-saradc", 914 .data = &meson_sar_adc_meson8b_data, 915 }, 916 { 917 .compatible = "amlogic,meson-gxbb-saradc", 918 .data = &meson_sar_adc_gxbb_data, 919 }, { 920 .compatible = "amlogic,meson-gxl-saradc", 921 .data = &meson_sar_adc_gxl_data, 922 }, { 923 .compatible = "amlogic,meson-gxm-saradc", 924 .data = &meson_sar_adc_gxm_data, 925 }, 926 {}, 927 }; 928 MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match); 929 930 static int meson_sar_adc_probe(struct platform_device *pdev) 931 { 932 struct meson_sar_adc_priv *priv; 933 struct iio_dev *indio_dev; 934 struct resource *res; 935 void __iomem *base; 936 const struct of_device_id *match; 937 int irq, ret; 938 939 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv)); 940 if (!indio_dev) { 941 dev_err(&pdev->dev, "failed allocating iio device\n"); 942 return -ENOMEM; 943 } 944 945 priv = iio_priv(indio_dev); 946 init_completion(&priv->done); 947 948 match = of_match_device(meson_sar_adc_of_match, &pdev->dev); 949 if (!match) { 950 dev_err(&pdev->dev, "failed to match device\n"); 951 return -ENODEV; 952 } 953 954 priv->data = match->data; 955 956 indio_dev->name = priv->data->name; 957 indio_dev->dev.parent = &pdev->dev; 958 indio_dev->dev.of_node = pdev->dev.of_node; 959 indio_dev->modes = INDIO_DIRECT_MODE; 960 indio_dev->info = &meson_sar_adc_iio_info; 961 962 indio_dev->channels = meson_sar_adc_iio_channels; 963 indio_dev->num_channels = ARRAY_SIZE(meson_sar_adc_iio_channels); 964 965 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 966 base = devm_ioremap_resource(&pdev->dev, res); 967 if (IS_ERR(base)) 968 return PTR_ERR(base); 969 970 irq = irq_of_parse_and_map(pdev->dev.of_node, 0); 971 if (!irq) 972 return -EINVAL; 973 974 ret = devm_request_irq(&pdev->dev, irq, meson_sar_adc_irq, IRQF_SHARED, 975 dev_name(&pdev->dev), indio_dev); 976 if (ret) 977 return ret; 978 979 priv->regmap = devm_regmap_init_mmio(&pdev->dev, base, 980 priv->data->regmap_config); 981 if (IS_ERR(priv->regmap)) 982 return PTR_ERR(priv->regmap); 983 984 priv->clkin = devm_clk_get(&pdev->dev, "clkin"); 985 if (IS_ERR(priv->clkin)) { 986 dev_err(&pdev->dev, "failed to get clkin\n"); 987 return PTR_ERR(priv->clkin); 988 } 989 990 priv->core_clk = devm_clk_get(&pdev->dev, "core"); 991 if (IS_ERR(priv->core_clk)) { 992 dev_err(&pdev->dev, "failed to get core clk\n"); 993 return PTR_ERR(priv->core_clk); 994 } 995 996 priv->sana_clk = devm_clk_get(&pdev->dev, "sana"); 997 if (IS_ERR(priv->sana_clk)) { 998 if (PTR_ERR(priv->sana_clk) == -ENOENT) { 999 priv->sana_clk = NULL; 1000 } else { 1001 dev_err(&pdev->dev, "failed to get sana clk\n"); 1002 return PTR_ERR(priv->sana_clk); 1003 } 1004 } 1005 1006 priv->adc_clk = devm_clk_get(&pdev->dev, "adc_clk"); 1007 if (IS_ERR(priv->adc_clk)) { 1008 if (PTR_ERR(priv->adc_clk) == -ENOENT) { 1009 priv->adc_clk = NULL; 1010 } else { 1011 dev_err(&pdev->dev, "failed to get adc clk\n"); 1012 return PTR_ERR(priv->adc_clk); 1013 } 1014 } 1015 1016 priv->adc_sel_clk = devm_clk_get(&pdev->dev, "adc_sel"); 1017 if (IS_ERR(priv->adc_sel_clk)) { 1018 if (PTR_ERR(priv->adc_sel_clk) == -ENOENT) { 1019 priv->adc_sel_clk = NULL; 1020 } else { 1021 dev_err(&pdev->dev, "failed to get adc_sel clk\n"); 1022 return PTR_ERR(priv->adc_sel_clk); 1023 } 1024 } 1025 1026 /* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */ 1027 if (!priv->adc_clk) { 1028 ret = meson_sar_adc_clk_init(indio_dev, base); 1029 if (ret) 1030 return ret; 1031 } 1032 1033 priv->vref = devm_regulator_get(&pdev->dev, "vref"); 1034 if (IS_ERR(priv->vref)) { 1035 dev_err(&pdev->dev, "failed to get vref regulator\n"); 1036 return PTR_ERR(priv->vref); 1037 } 1038 1039 priv->calibscale = MILLION; 1040 1041 ret = meson_sar_adc_init(indio_dev); 1042 if (ret) 1043 goto err; 1044 1045 ret = meson_sar_adc_hw_enable(indio_dev); 1046 if (ret) 1047 goto err; 1048 1049 ret = meson_sar_adc_calib(indio_dev); 1050 if (ret) 1051 dev_warn(&pdev->dev, "calibration failed\n"); 1052 1053 platform_set_drvdata(pdev, indio_dev); 1054 1055 ret = iio_device_register(indio_dev); 1056 if (ret) 1057 goto err_hw; 1058 1059 return 0; 1060 1061 err_hw: 1062 meson_sar_adc_hw_disable(indio_dev); 1063 err: 1064 return ret; 1065 } 1066 1067 static int meson_sar_adc_remove(struct platform_device *pdev) 1068 { 1069 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 1070 1071 iio_device_unregister(indio_dev); 1072 1073 return meson_sar_adc_hw_disable(indio_dev); 1074 } 1075 1076 static int __maybe_unused meson_sar_adc_suspend(struct device *dev) 1077 { 1078 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1079 1080 return meson_sar_adc_hw_disable(indio_dev); 1081 } 1082 1083 static int __maybe_unused meson_sar_adc_resume(struct device *dev) 1084 { 1085 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1086 1087 return meson_sar_adc_hw_enable(indio_dev); 1088 } 1089 1090 static SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops, 1091 meson_sar_adc_suspend, meson_sar_adc_resume); 1092 1093 static struct platform_driver meson_sar_adc_driver = { 1094 .probe = meson_sar_adc_probe, 1095 .remove = meson_sar_adc_remove, 1096 .driver = { 1097 .name = "meson-saradc", 1098 .of_match_table = meson_sar_adc_of_match, 1099 .pm = &meson_sar_adc_pm_ops, 1100 }, 1101 }; 1102 1103 module_platform_driver(meson_sar_adc_driver); 1104 1105 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>"); 1106 MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver"); 1107 MODULE_LICENSE("GPL v2"); 1108