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 unsigned int resolution; 225 const char *name; 226 }; 227 228 struct meson_sar_adc_priv { 229 struct regmap *regmap; 230 struct regulator *vref; 231 const struct meson_sar_adc_data *data; 232 struct clk *clkin; 233 struct clk *core_clk; 234 struct clk *sana_clk; 235 struct clk *adc_sel_clk; 236 struct clk *adc_clk; 237 struct clk_gate clk_gate; 238 struct clk *adc_div_clk; 239 struct clk_divider clk_div; 240 struct completion done; 241 int calibbias; 242 int calibscale; 243 }; 244 245 static const struct regmap_config meson_sar_adc_regmap_config = { 246 .reg_bits = 8, 247 .val_bits = 32, 248 .reg_stride = 4, 249 .max_register = MESON_SAR_ADC_REG13, 250 }; 251 252 static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev) 253 { 254 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 255 u32 regval; 256 257 regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); 258 259 return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval); 260 } 261 262 static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val) 263 { 264 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 265 int tmp; 266 267 /* use val_calib = scale * val_raw + offset calibration function */ 268 tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias; 269 270 return clamp(tmp, 0, (1 << priv->data->resolution) - 1); 271 } 272 273 static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev) 274 { 275 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 276 int regval, timeout = 10000; 277 278 /* 279 * NOTE: we need a small delay before reading the status, otherwise 280 * the sample engine may not have started internally (which would 281 * seem to us that sampling is already finished). 282 */ 283 do { 284 udelay(1); 285 regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); 286 } while (FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, regval) && timeout--); 287 288 if (timeout < 0) 289 return -ETIMEDOUT; 290 291 return 0; 292 } 293 294 static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev, 295 const struct iio_chan_spec *chan, 296 int *val) 297 { 298 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 299 int regval, fifo_chan, fifo_val, count; 300 301 if(!wait_for_completion_timeout(&priv->done, 302 msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT))) 303 return -ETIMEDOUT; 304 305 count = meson_sar_adc_get_fifo_count(indio_dev); 306 if (count != 1) { 307 dev_err(&indio_dev->dev, 308 "ADC FIFO has %d element(s) instead of one\n", count); 309 return -EINVAL; 310 } 311 312 regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, ®val); 313 fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval); 314 if (fifo_chan != chan->channel) { 315 dev_err(&indio_dev->dev, 316 "ADC FIFO entry belongs to channel %d instead of %d\n", 317 fifo_chan, chan->channel); 318 return -EINVAL; 319 } 320 321 fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval); 322 fifo_val &= GENMASK(priv->data->resolution - 1, 0); 323 *val = meson_sar_adc_calib_val(indio_dev, fifo_val); 324 325 return 0; 326 } 327 328 static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev, 329 const struct iio_chan_spec *chan, 330 enum meson_sar_adc_avg_mode mode, 331 enum meson_sar_adc_num_samples samples) 332 { 333 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 334 int val, channel = chan->channel; 335 336 val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(channel); 337 regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL, 338 MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(channel), 339 val); 340 341 val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(channel); 342 regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL, 343 MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(channel), val); 344 } 345 346 static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev, 347 const struct iio_chan_spec *chan) 348 { 349 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 350 u32 regval; 351 352 /* 353 * the SAR ADC engine allows sampling multiple channels at the same 354 * time. to keep it simple we're only working with one *internal* 355 * channel, which starts counting at index 0 (which means: count = 1). 356 */ 357 regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0); 358 regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 359 MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval); 360 361 /* map channel index 0 to the channel which we want to read */ 362 regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), 363 chan->channel); 364 regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 365 MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval); 366 367 regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK, 368 chan->channel); 369 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW, 370 MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK, 371 regval); 372 373 regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK, 374 chan->channel); 375 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW, 376 MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK, 377 regval); 378 379 if (chan->channel == 6) 380 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10, 381 MESON_SAR_ADC_DELTA_10_TEMP_SEL, 0); 382 } 383 384 static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev, 385 enum meson_sar_adc_chan7_mux_sel sel) 386 { 387 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 388 u32 regval; 389 390 regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel); 391 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 392 MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval); 393 394 usleep_range(10, 20); 395 } 396 397 static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev) 398 { 399 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 400 401 reinit_completion(&priv->done); 402 403 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 404 MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 405 MESON_SAR_ADC_REG0_FIFO_IRQ_EN); 406 407 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 408 MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 409 MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE); 410 411 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 412 MESON_SAR_ADC_REG0_SAMPLING_START, 413 MESON_SAR_ADC_REG0_SAMPLING_START); 414 } 415 416 static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev) 417 { 418 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 419 420 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 421 MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0); 422 423 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 424 MESON_SAR_ADC_REG0_SAMPLING_STOP, 425 MESON_SAR_ADC_REG0_SAMPLING_STOP); 426 427 /* wait until all modules are stopped */ 428 meson_sar_adc_wait_busy_clear(indio_dev); 429 430 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 431 MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0); 432 } 433 434 static int meson_sar_adc_lock(struct iio_dev *indio_dev) 435 { 436 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 437 int val, timeout = 10000; 438 439 mutex_lock(&indio_dev->mlock); 440 441 if (priv->data->has_bl30_integration) { 442 /* prevent BL30 from using the SAR ADC while we are using it */ 443 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 444 MESON_SAR_ADC_DELAY_KERNEL_BUSY, 445 MESON_SAR_ADC_DELAY_KERNEL_BUSY); 446 447 /* 448 * wait until BL30 releases it's lock (so we can use the SAR 449 * ADC) 450 */ 451 do { 452 udelay(1); 453 regmap_read(priv->regmap, MESON_SAR_ADC_DELAY, &val); 454 } while (val & MESON_SAR_ADC_DELAY_BL30_BUSY && timeout--); 455 456 if (timeout < 0) 457 return -ETIMEDOUT; 458 } 459 460 return 0; 461 } 462 463 static void meson_sar_adc_unlock(struct iio_dev *indio_dev) 464 { 465 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 466 467 if (priv->data->has_bl30_integration) 468 /* allow BL30 to use the SAR ADC again */ 469 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 470 MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0); 471 472 mutex_unlock(&indio_dev->mlock); 473 } 474 475 static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev) 476 { 477 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 478 unsigned int count, tmp; 479 480 for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) { 481 if (!meson_sar_adc_get_fifo_count(indio_dev)) 482 break; 483 484 regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp); 485 } 486 } 487 488 static int meson_sar_adc_get_sample(struct iio_dev *indio_dev, 489 const struct iio_chan_spec *chan, 490 enum meson_sar_adc_avg_mode avg_mode, 491 enum meson_sar_adc_num_samples avg_samples, 492 int *val) 493 { 494 int ret; 495 496 ret = meson_sar_adc_lock(indio_dev); 497 if (ret) 498 return ret; 499 500 /* clear the FIFO to make sure we're not reading old values */ 501 meson_sar_adc_clear_fifo(indio_dev); 502 503 meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples); 504 505 meson_sar_adc_enable_channel(indio_dev, chan); 506 507 meson_sar_adc_start_sample_engine(indio_dev); 508 ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val); 509 meson_sar_adc_stop_sample_engine(indio_dev); 510 511 meson_sar_adc_unlock(indio_dev); 512 513 if (ret) { 514 dev_warn(indio_dev->dev.parent, 515 "failed to read sample for channel %d: %d\n", 516 chan->channel, ret); 517 return ret; 518 } 519 520 return IIO_VAL_INT; 521 } 522 523 static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev, 524 const struct iio_chan_spec *chan, 525 int *val, int *val2, long mask) 526 { 527 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 528 int ret; 529 530 switch (mask) { 531 case IIO_CHAN_INFO_RAW: 532 return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING, 533 ONE_SAMPLE, val); 534 break; 535 536 case IIO_CHAN_INFO_AVERAGE_RAW: 537 return meson_sar_adc_get_sample(indio_dev, chan, 538 MEAN_AVERAGING, EIGHT_SAMPLES, 539 val); 540 break; 541 542 case IIO_CHAN_INFO_SCALE: 543 ret = regulator_get_voltage(priv->vref); 544 if (ret < 0) { 545 dev_err(indio_dev->dev.parent, 546 "failed to get vref voltage: %d\n", ret); 547 return ret; 548 } 549 550 *val = ret / 1000; 551 *val2 = priv->data->resolution; 552 return IIO_VAL_FRACTIONAL_LOG2; 553 554 case IIO_CHAN_INFO_CALIBBIAS: 555 *val = priv->calibbias; 556 return IIO_VAL_INT; 557 558 case IIO_CHAN_INFO_CALIBSCALE: 559 *val = priv->calibscale / MILLION; 560 *val2 = priv->calibscale % MILLION; 561 return IIO_VAL_INT_PLUS_MICRO; 562 563 default: 564 return -EINVAL; 565 } 566 } 567 568 static int meson_sar_adc_clk_init(struct iio_dev *indio_dev, 569 void __iomem *base) 570 { 571 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 572 struct clk_init_data init; 573 const char *clk_parents[1]; 574 575 init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%pOF#adc_div", 576 indio_dev->dev.of_node); 577 init.flags = 0; 578 init.ops = &clk_divider_ops; 579 clk_parents[0] = __clk_get_name(priv->clkin); 580 init.parent_names = clk_parents; 581 init.num_parents = 1; 582 583 priv->clk_div.reg = base + MESON_SAR_ADC_REG3; 584 priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT; 585 priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH; 586 priv->clk_div.hw.init = &init; 587 priv->clk_div.flags = 0; 588 589 priv->adc_div_clk = devm_clk_register(&indio_dev->dev, 590 &priv->clk_div.hw); 591 if (WARN_ON(IS_ERR(priv->adc_div_clk))) 592 return PTR_ERR(priv->adc_div_clk); 593 594 init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%pOF#adc_en", 595 indio_dev->dev.of_node); 596 init.flags = CLK_SET_RATE_PARENT; 597 init.ops = &clk_gate_ops; 598 clk_parents[0] = __clk_get_name(priv->adc_div_clk); 599 init.parent_names = clk_parents; 600 init.num_parents = 1; 601 602 priv->clk_gate.reg = base + MESON_SAR_ADC_REG3; 603 priv->clk_gate.bit_idx = fls(MESON_SAR_ADC_REG3_CLK_EN); 604 priv->clk_gate.hw.init = &init; 605 606 priv->adc_clk = devm_clk_register(&indio_dev->dev, &priv->clk_gate.hw); 607 if (WARN_ON(IS_ERR(priv->adc_clk))) 608 return PTR_ERR(priv->adc_clk); 609 610 return 0; 611 } 612 613 static int meson_sar_adc_init(struct iio_dev *indio_dev) 614 { 615 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 616 int regval, ret; 617 618 /* 619 * make sure we start at CH7 input since the other muxes are only used 620 * for internal calibration. 621 */ 622 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT); 623 624 if (priv->data->has_bl30_integration) { 625 /* 626 * leave sampling delay and the input clocks as configured by 627 * BL30 to make sure BL30 gets the values it expects when 628 * reading the temperature sensor. 629 */ 630 regmap_read(priv->regmap, MESON_SAR_ADC_REG3, ®val); 631 if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED) 632 return 0; 633 } 634 635 meson_sar_adc_stop_sample_engine(indio_dev); 636 637 /* update the channel 6 MUX to select the temperature sensor */ 638 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 639 MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 640 MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL); 641 642 /* disable all channels by default */ 643 regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0); 644 645 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 646 MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0); 647 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 648 MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY, 649 MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY); 650 651 /* delay between two samples = (10+1) * 1uS */ 652 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 653 MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK, 654 FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK, 655 10)); 656 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 657 MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK, 658 FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK, 659 0)); 660 661 /* delay between two samples = (10+1) * 1uS */ 662 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 663 MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK, 664 FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK, 665 10)); 666 regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY, 667 MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK, 668 FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK, 669 1)); 670 671 ret = clk_set_parent(priv->adc_sel_clk, priv->clkin); 672 if (ret) { 673 dev_err(indio_dev->dev.parent, 674 "failed to set adc parent to clkin\n"); 675 return ret; 676 } 677 678 ret = clk_set_rate(priv->adc_clk, 1200000); 679 if (ret) { 680 dev_err(indio_dev->dev.parent, 681 "failed to set adc clock rate\n"); 682 return ret; 683 } 684 685 return 0; 686 } 687 688 static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev) 689 { 690 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 691 int ret; 692 u32 regval; 693 694 ret = meson_sar_adc_lock(indio_dev); 695 if (ret) 696 goto err_lock; 697 698 ret = regulator_enable(priv->vref); 699 if (ret < 0) { 700 dev_err(indio_dev->dev.parent, 701 "failed to enable vref regulator\n"); 702 goto err_vref; 703 } 704 705 ret = clk_prepare_enable(priv->core_clk); 706 if (ret) { 707 dev_err(indio_dev->dev.parent, "failed to enable core clk\n"); 708 goto err_core_clk; 709 } 710 711 ret = clk_prepare_enable(priv->sana_clk); 712 if (ret) { 713 dev_err(indio_dev->dev.parent, "failed to enable sana clk\n"); 714 goto err_sana_clk; 715 } 716 717 regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1); 718 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0, 719 MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval); 720 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11, 721 MESON_SAR_ADC_REG11_BANDGAP_EN, 722 MESON_SAR_ADC_REG11_BANDGAP_EN); 723 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 724 MESON_SAR_ADC_REG3_ADC_EN, 725 MESON_SAR_ADC_REG3_ADC_EN); 726 727 udelay(5); 728 729 ret = clk_prepare_enable(priv->adc_clk); 730 if (ret) { 731 dev_err(indio_dev->dev.parent, "failed to enable adc clk\n"); 732 goto err_adc_clk; 733 } 734 735 meson_sar_adc_unlock(indio_dev); 736 737 return 0; 738 739 err_adc_clk: 740 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 741 MESON_SAR_ADC_REG3_ADC_EN, 0); 742 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11, 743 MESON_SAR_ADC_REG11_BANDGAP_EN, 0); 744 clk_disable_unprepare(priv->sana_clk); 745 err_sana_clk: 746 clk_disable_unprepare(priv->core_clk); 747 err_core_clk: 748 regulator_disable(priv->vref); 749 err_vref: 750 meson_sar_adc_unlock(indio_dev); 751 err_lock: 752 return ret; 753 } 754 755 static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev) 756 { 757 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 758 int ret; 759 760 ret = meson_sar_adc_lock(indio_dev); 761 if (ret) 762 return ret; 763 764 clk_disable_unprepare(priv->adc_clk); 765 766 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3, 767 MESON_SAR_ADC_REG3_ADC_EN, 0); 768 regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11, 769 MESON_SAR_ADC_REG11_BANDGAP_EN, 0); 770 771 clk_disable_unprepare(priv->sana_clk); 772 clk_disable_unprepare(priv->core_clk); 773 774 regulator_disable(priv->vref); 775 776 meson_sar_adc_unlock(indio_dev); 777 778 return 0; 779 } 780 781 static irqreturn_t meson_sar_adc_irq(int irq, void *data) 782 { 783 struct iio_dev *indio_dev = data; 784 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 785 unsigned int cnt, threshold; 786 u32 regval; 787 788 regmap_read(priv->regmap, MESON_SAR_ADC_REG0, ®val); 789 cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval); 790 threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval); 791 792 if (cnt < threshold) 793 return IRQ_NONE; 794 795 complete(&priv->done); 796 797 return IRQ_HANDLED; 798 } 799 800 static int meson_sar_adc_calib(struct iio_dev *indio_dev) 801 { 802 struct meson_sar_adc_priv *priv = iio_priv(indio_dev); 803 int ret, nominal0, nominal1, value0, value1; 804 805 /* use points 25% and 75% for calibration */ 806 nominal0 = (1 << priv->data->resolution) / 4; 807 nominal1 = (1 << priv->data->resolution) * 3 / 4; 808 809 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4); 810 usleep_range(10, 20); 811 ret = meson_sar_adc_get_sample(indio_dev, 812 &meson_sar_adc_iio_channels[7], 813 MEAN_AVERAGING, EIGHT_SAMPLES, &value0); 814 if (ret < 0) 815 goto out; 816 817 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4); 818 usleep_range(10, 20); 819 ret = meson_sar_adc_get_sample(indio_dev, 820 &meson_sar_adc_iio_channels[7], 821 MEAN_AVERAGING, EIGHT_SAMPLES, &value1); 822 if (ret < 0) 823 goto out; 824 825 if (value1 <= value0) { 826 ret = -EINVAL; 827 goto out; 828 } 829 830 priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION, 831 value1 - value0); 832 priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale, 833 MILLION); 834 ret = 0; 835 out: 836 meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT); 837 838 return ret; 839 } 840 841 static const struct iio_info meson_sar_adc_iio_info = { 842 .read_raw = meson_sar_adc_iio_info_read_raw, 843 .driver_module = THIS_MODULE, 844 }; 845 846 static const struct meson_sar_adc_data meson_sar_adc_meson8_data = { 847 .has_bl30_integration = false, 848 .resolution = 10, 849 .name = "meson-meson8-saradc", 850 }; 851 852 static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = { 853 .has_bl30_integration = false, 854 .resolution = 10, 855 .name = "meson-meson8b-saradc", 856 }; 857 858 static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = { 859 .has_bl30_integration = true, 860 .resolution = 10, 861 .name = "meson-gxbb-saradc", 862 }; 863 864 static const struct meson_sar_adc_data meson_sar_adc_gxl_data = { 865 .has_bl30_integration = true, 866 .resolution = 12, 867 .name = "meson-gxl-saradc", 868 }; 869 870 static const struct meson_sar_adc_data meson_sar_adc_gxm_data = { 871 .has_bl30_integration = true, 872 .resolution = 12, 873 .name = "meson-gxm-saradc", 874 }; 875 876 static const struct of_device_id meson_sar_adc_of_match[] = { 877 { 878 .compatible = "amlogic,meson8-saradc", 879 .data = &meson_sar_adc_meson8_data, 880 }, 881 { 882 .compatible = "amlogic,meson8b-saradc", 883 .data = &meson_sar_adc_meson8b_data, 884 }, 885 { 886 .compatible = "amlogic,meson-gxbb-saradc", 887 .data = &meson_sar_adc_gxbb_data, 888 }, { 889 .compatible = "amlogic,meson-gxl-saradc", 890 .data = &meson_sar_adc_gxl_data, 891 }, { 892 .compatible = "amlogic,meson-gxm-saradc", 893 .data = &meson_sar_adc_gxm_data, 894 }, 895 {}, 896 }; 897 MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match); 898 899 static int meson_sar_adc_probe(struct platform_device *pdev) 900 { 901 struct meson_sar_adc_priv *priv; 902 struct iio_dev *indio_dev; 903 struct resource *res; 904 void __iomem *base; 905 const struct of_device_id *match; 906 int irq, ret; 907 908 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv)); 909 if (!indio_dev) { 910 dev_err(&pdev->dev, "failed allocating iio device\n"); 911 return -ENOMEM; 912 } 913 914 priv = iio_priv(indio_dev); 915 init_completion(&priv->done); 916 917 match = of_match_device(meson_sar_adc_of_match, &pdev->dev); 918 if (!match) { 919 dev_err(&pdev->dev, "failed to match device\n"); 920 return -ENODEV; 921 } 922 923 priv->data = match->data; 924 925 indio_dev->name = priv->data->name; 926 indio_dev->dev.parent = &pdev->dev; 927 indio_dev->dev.of_node = pdev->dev.of_node; 928 indio_dev->modes = INDIO_DIRECT_MODE; 929 indio_dev->info = &meson_sar_adc_iio_info; 930 931 indio_dev->channels = meson_sar_adc_iio_channels; 932 indio_dev->num_channels = ARRAY_SIZE(meson_sar_adc_iio_channels); 933 934 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 935 base = devm_ioremap_resource(&pdev->dev, res); 936 if (IS_ERR(base)) 937 return PTR_ERR(base); 938 939 irq = irq_of_parse_and_map(pdev->dev.of_node, 0); 940 if (!irq) 941 return -EINVAL; 942 943 ret = devm_request_irq(&pdev->dev, irq, meson_sar_adc_irq, IRQF_SHARED, 944 dev_name(&pdev->dev), indio_dev); 945 if (ret) 946 return ret; 947 948 priv->regmap = devm_regmap_init_mmio(&pdev->dev, base, 949 &meson_sar_adc_regmap_config); 950 if (IS_ERR(priv->regmap)) 951 return PTR_ERR(priv->regmap); 952 953 priv->clkin = devm_clk_get(&pdev->dev, "clkin"); 954 if (IS_ERR(priv->clkin)) { 955 dev_err(&pdev->dev, "failed to get clkin\n"); 956 return PTR_ERR(priv->clkin); 957 } 958 959 priv->core_clk = devm_clk_get(&pdev->dev, "core"); 960 if (IS_ERR(priv->core_clk)) { 961 dev_err(&pdev->dev, "failed to get core clk\n"); 962 return PTR_ERR(priv->core_clk); 963 } 964 965 priv->sana_clk = devm_clk_get(&pdev->dev, "sana"); 966 if (IS_ERR(priv->sana_clk)) { 967 if (PTR_ERR(priv->sana_clk) == -ENOENT) { 968 priv->sana_clk = NULL; 969 } else { 970 dev_err(&pdev->dev, "failed to get sana clk\n"); 971 return PTR_ERR(priv->sana_clk); 972 } 973 } 974 975 priv->adc_clk = devm_clk_get(&pdev->dev, "adc_clk"); 976 if (IS_ERR(priv->adc_clk)) { 977 if (PTR_ERR(priv->adc_clk) == -ENOENT) { 978 priv->adc_clk = NULL; 979 } else { 980 dev_err(&pdev->dev, "failed to get adc clk\n"); 981 return PTR_ERR(priv->adc_clk); 982 } 983 } 984 985 priv->adc_sel_clk = devm_clk_get(&pdev->dev, "adc_sel"); 986 if (IS_ERR(priv->adc_sel_clk)) { 987 if (PTR_ERR(priv->adc_sel_clk) == -ENOENT) { 988 priv->adc_sel_clk = NULL; 989 } else { 990 dev_err(&pdev->dev, "failed to get adc_sel clk\n"); 991 return PTR_ERR(priv->adc_sel_clk); 992 } 993 } 994 995 /* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */ 996 if (!priv->adc_clk) { 997 ret = meson_sar_adc_clk_init(indio_dev, base); 998 if (ret) 999 return ret; 1000 } 1001 1002 priv->vref = devm_regulator_get(&pdev->dev, "vref"); 1003 if (IS_ERR(priv->vref)) { 1004 dev_err(&pdev->dev, "failed to get vref regulator\n"); 1005 return PTR_ERR(priv->vref); 1006 } 1007 1008 priv->calibscale = MILLION; 1009 1010 ret = meson_sar_adc_init(indio_dev); 1011 if (ret) 1012 goto err; 1013 1014 ret = meson_sar_adc_hw_enable(indio_dev); 1015 if (ret) 1016 goto err; 1017 1018 ret = meson_sar_adc_calib(indio_dev); 1019 if (ret) 1020 dev_warn(&pdev->dev, "calibration failed\n"); 1021 1022 platform_set_drvdata(pdev, indio_dev); 1023 1024 ret = iio_device_register(indio_dev); 1025 if (ret) 1026 goto err_hw; 1027 1028 return 0; 1029 1030 err_hw: 1031 meson_sar_adc_hw_disable(indio_dev); 1032 err: 1033 return ret; 1034 } 1035 1036 static int meson_sar_adc_remove(struct platform_device *pdev) 1037 { 1038 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 1039 1040 iio_device_unregister(indio_dev); 1041 1042 return meson_sar_adc_hw_disable(indio_dev); 1043 } 1044 1045 static int __maybe_unused meson_sar_adc_suspend(struct device *dev) 1046 { 1047 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1048 1049 return meson_sar_adc_hw_disable(indio_dev); 1050 } 1051 1052 static int __maybe_unused meson_sar_adc_resume(struct device *dev) 1053 { 1054 struct iio_dev *indio_dev = dev_get_drvdata(dev); 1055 1056 return meson_sar_adc_hw_enable(indio_dev); 1057 } 1058 1059 static SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops, 1060 meson_sar_adc_suspend, meson_sar_adc_resume); 1061 1062 static struct platform_driver meson_sar_adc_driver = { 1063 .probe = meson_sar_adc_probe, 1064 .remove = meson_sar_adc_remove, 1065 .driver = { 1066 .name = "meson-saradc", 1067 .of_match_table = meson_sar_adc_of_match, 1068 .pm = &meson_sar_adc_pm_ops, 1069 }, 1070 }; 1071 1072 module_platform_driver(meson_sar_adc_driver); 1073 1074 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>"); 1075 MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver"); 1076 MODULE_LICENSE("GPL v2"); 1077