xref: /openbmc/linux/drivers/iio/adc/meson_saradc.c (revision 53f9cd5c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Amlogic Meson Successive Approximation Register (SAR) A/D Converter
4  *
5  * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13 #include <linux/iio/iio.h>
14 #include <linux/module.h>
15 #include <linux/nvmem-consumer.h>
16 #include <linux/interrupt.h>
17 #include <linux/of.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_device.h>
20 #include <linux/platform_device.h>
21 #include <linux/regmap.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/mfd/syscon.h>
24 
25 #define MESON_SAR_ADC_REG0					0x00
26 	#define MESON_SAR_ADC_REG0_PANEL_DETECT			BIT(31)
27 	#define MESON_SAR_ADC_REG0_BUSY_MASK			GENMASK(30, 28)
28 	#define MESON_SAR_ADC_REG0_DELTA_BUSY			BIT(30)
29 	#define MESON_SAR_ADC_REG0_AVG_BUSY			BIT(29)
30 	#define MESON_SAR_ADC_REG0_SAMPLE_BUSY			BIT(28)
31 	#define MESON_SAR_ADC_REG0_FIFO_FULL			BIT(27)
32 	#define MESON_SAR_ADC_REG0_FIFO_EMPTY			BIT(26)
33 	#define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK		GENMASK(25, 21)
34 	#define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK		GENMASK(20, 19)
35 	#define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK		GENMASK(18, 16)
36 	#define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL		BIT(15)
37 	#define MESON_SAR_ADC_REG0_SAMPLING_STOP		BIT(14)
38 	#define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK		GENMASK(13, 12)
39 	#define MESON_SAR_ADC_REG0_DETECT_IRQ_POL		BIT(10)
40 	#define MESON_SAR_ADC_REG0_DETECT_IRQ_EN		BIT(9)
41 	#define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK		GENMASK(8, 4)
42 	#define MESON_SAR_ADC_REG0_FIFO_IRQ_EN			BIT(3)
43 	#define MESON_SAR_ADC_REG0_SAMPLING_START		BIT(2)
44 	#define MESON_SAR_ADC_REG0_CONTINUOUS_EN		BIT(1)
45 	#define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE		BIT(0)
46 
47 #define MESON_SAR_ADC_CHAN_LIST					0x04
48 	#define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK		GENMASK(26, 24)
49 	#define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan)	\
50 					(GENMASK(2, 0) << ((_chan) * 3))
51 
52 #define MESON_SAR_ADC_AVG_CNTL					0x08
53 	#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan)	\
54 					(16 + ((_chan) * 2))
55 	#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan)	\
56 					(GENMASK(17, 16) << ((_chan) * 2))
57 	#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan)	\
58 					(0 + ((_chan) * 2))
59 	#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan)	\
60 					(GENMASK(1, 0) << ((_chan) * 2))
61 
62 #define MESON_SAR_ADC_REG3					0x0c
63 	#define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY		BIT(31)
64 	#define MESON_SAR_ADC_REG3_CLK_EN			BIT(30)
65 	#define MESON_SAR_ADC_REG3_BL30_INITIALIZED		BIT(28)
66 	#define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN	BIT(27)
67 	#define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE	BIT(26)
68 	#define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK	GENMASK(25, 23)
69 	#define MESON_SAR_ADC_REG3_DETECT_EN			BIT(22)
70 	#define MESON_SAR_ADC_REG3_ADC_EN			BIT(21)
71 	#define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK	GENMASK(20, 18)
72 	#define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK	GENMASK(17, 16)
73 	#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT		10
74 	#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH		5
75 	#define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK		GENMASK(9, 8)
76 	#define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK		GENMASK(7, 0)
77 
78 #define MESON_SAR_ADC_DELAY					0x10
79 	#define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK		GENMASK(25, 24)
80 	#define MESON_SAR_ADC_DELAY_BL30_BUSY			BIT(15)
81 	#define MESON_SAR_ADC_DELAY_KERNEL_BUSY			BIT(14)
82 	#define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK		GENMASK(23, 16)
83 	#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK		GENMASK(9, 8)
84 	#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK		GENMASK(7, 0)
85 
86 #define MESON_SAR_ADC_LAST_RD					0x14
87 	#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK	GENMASK(23, 16)
88 	#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK	GENMASK(9, 0)
89 
90 #define MESON_SAR_ADC_FIFO_RD					0x18
91 	#define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK		GENMASK(14, 12)
92 	#define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK		GENMASK(11, 0)
93 
94 #define MESON_SAR_ADC_AUX_SW					0x1c
95 	#define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan)	\
96 					(8 + (((_chan) - 2) * 3))
97 	#define MESON_SAR_ADC_AUX_SW_VREF_P_MUX			BIT(6)
98 	#define MESON_SAR_ADC_AUX_SW_VREF_N_MUX			BIT(5)
99 	#define MESON_SAR_ADC_AUX_SW_MODE_SEL			BIT(4)
100 	#define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW		BIT(3)
101 	#define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW		BIT(2)
102 	#define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW		BIT(1)
103 	#define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW		BIT(0)
104 
105 #define MESON_SAR_ADC_CHAN_10_SW				0x20
106 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK	GENMASK(25, 23)
107 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX	BIT(22)
108 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX	BIT(21)
109 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL		BIT(20)
110 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW	BIT(19)
111 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW	BIT(18)
112 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW	BIT(17)
113 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW	BIT(16)
114 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK	GENMASK(9, 7)
115 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX	BIT(6)
116 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX	BIT(5)
117 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL		BIT(4)
118 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW	BIT(3)
119 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW	BIT(2)
120 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW	BIT(1)
121 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW	BIT(0)
122 
123 #define MESON_SAR_ADC_DETECT_IDLE_SW				0x24
124 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN	BIT(26)
125 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK	GENMASK(25, 23)
126 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX	BIT(22)
127 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX	BIT(21)
128 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL	BIT(20)
129 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW	BIT(19)
130 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW	BIT(18)
131 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW	BIT(17)
132 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW	BIT(16)
133 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK	GENMASK(9, 7)
134 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX	BIT(6)
135 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX	BIT(5)
136 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL	BIT(4)
137 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW	BIT(3)
138 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW	BIT(2)
139 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW	BIT(1)
140 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW	BIT(0)
141 
142 #define MESON_SAR_ADC_DELTA_10					0x28
143 	#define MESON_SAR_ADC_DELTA_10_TEMP_SEL			BIT(27)
144 	#define MESON_SAR_ADC_DELTA_10_TS_REVE1			BIT(26)
145 	#define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK	GENMASK(25, 16)
146 	#define MESON_SAR_ADC_DELTA_10_TS_REVE0			BIT(15)
147 	#define MESON_SAR_ADC_DELTA_10_TS_C_MASK		GENMASK(14, 11)
148 	#define MESON_SAR_ADC_DELTA_10_TS_VBG_EN		BIT(10)
149 	#define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK	GENMASK(9, 0)
150 
151 /*
152  * NOTE: registers from here are undocumented (the vendor Linux kernel driver
153  * and u-boot source served as reference). These only seem to be relevant on
154  * GXBB and newer.
155  */
156 #define MESON_SAR_ADC_REG11					0x2c
157 	#define MESON_SAR_ADC_REG11_BANDGAP_EN			BIT(13)
158 
159 #define MESON_SAR_ADC_REG13					0x34
160 	#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK	GENMASK(13, 8)
161 
162 #define MESON_SAR_ADC_MAX_FIFO_SIZE				32
163 #define MESON_SAR_ADC_TIMEOUT					100 /* ms */
164 #define MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL			6
165 #define MESON_SAR_ADC_TEMP_OFFSET				27
166 
167 /* temperature sensor calibration information in eFuse */
168 #define MESON_SAR_ADC_EFUSE_BYTES				4
169 #define MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL			GENMASK(6, 0)
170 #define MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED			BIT(7)
171 
172 #define MESON_HHI_DPLL_TOP_0					0x318
173 #define MESON_HHI_DPLL_TOP_0_TSC_BIT4				BIT(9)
174 
175 /* for use with IIO_VAL_INT_PLUS_MICRO */
176 #define MILLION							1000000
177 
178 #define MESON_SAR_ADC_CHAN(_chan) {					\
179 	.type = IIO_VOLTAGE,						\
180 	.indexed = 1,							\
181 	.channel = _chan,						\
182 	.address = _chan,						\
183 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
184 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
185 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
186 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
187 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
188 	.datasheet_name = "SAR_ADC_CH"#_chan,				\
189 }
190 
191 #define MESON_SAR_ADC_TEMP_CHAN(_chan) {				\
192 	.type = IIO_TEMP,						\
193 	.channel = _chan,						\
194 	.address = MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL,		\
195 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
196 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
197 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |		\
198 					BIT(IIO_CHAN_INFO_SCALE),	\
199 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
200 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
201 	.datasheet_name = "TEMP_SENSOR",				\
202 }
203 
204 static const struct iio_chan_spec meson_sar_adc_iio_channels[] = {
205 	MESON_SAR_ADC_CHAN(0),
206 	MESON_SAR_ADC_CHAN(1),
207 	MESON_SAR_ADC_CHAN(2),
208 	MESON_SAR_ADC_CHAN(3),
209 	MESON_SAR_ADC_CHAN(4),
210 	MESON_SAR_ADC_CHAN(5),
211 	MESON_SAR_ADC_CHAN(6),
212 	MESON_SAR_ADC_CHAN(7),
213 	IIO_CHAN_SOFT_TIMESTAMP(8),
214 };
215 
216 static const struct iio_chan_spec meson_sar_adc_and_temp_iio_channels[] = {
217 	MESON_SAR_ADC_CHAN(0),
218 	MESON_SAR_ADC_CHAN(1),
219 	MESON_SAR_ADC_CHAN(2),
220 	MESON_SAR_ADC_CHAN(3),
221 	MESON_SAR_ADC_CHAN(4),
222 	MESON_SAR_ADC_CHAN(5),
223 	MESON_SAR_ADC_CHAN(6),
224 	MESON_SAR_ADC_CHAN(7),
225 	MESON_SAR_ADC_TEMP_CHAN(8),
226 	IIO_CHAN_SOFT_TIMESTAMP(9),
227 };
228 
229 enum meson_sar_adc_avg_mode {
230 	NO_AVERAGING = 0x0,
231 	MEAN_AVERAGING = 0x1,
232 	MEDIAN_AVERAGING = 0x2,
233 };
234 
235 enum meson_sar_adc_num_samples {
236 	ONE_SAMPLE = 0x0,
237 	TWO_SAMPLES = 0x1,
238 	FOUR_SAMPLES = 0x2,
239 	EIGHT_SAMPLES = 0x3,
240 };
241 
242 enum meson_sar_adc_chan7_mux_sel {
243 	CHAN7_MUX_VSS = 0x0,
244 	CHAN7_MUX_VDD_DIV4 = 0x1,
245 	CHAN7_MUX_VDD_DIV2 = 0x2,
246 	CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
247 	CHAN7_MUX_VDD = 0x4,
248 	CHAN7_MUX_CH7_INPUT = 0x7,
249 };
250 
251 struct meson_sar_adc_param {
252 	bool					has_bl30_integration;
253 	unsigned long				clock_rate;
254 	u32					bandgap_reg;
255 	unsigned int				resolution;
256 	const struct regmap_config		*regmap_config;
257 	u8					temperature_trimming_bits;
258 	unsigned int				temperature_multiplier;
259 	unsigned int				temperature_divider;
260 };
261 
262 struct meson_sar_adc_data {
263 	const struct meson_sar_adc_param	*param;
264 	const char				*name;
265 };
266 
267 struct meson_sar_adc_priv {
268 	struct regmap				*regmap;
269 	struct regulator			*vref;
270 	const struct meson_sar_adc_param	*param;
271 	struct clk				*clkin;
272 	struct clk				*core_clk;
273 	struct clk				*adc_sel_clk;
274 	struct clk				*adc_clk;
275 	struct clk_gate				clk_gate;
276 	struct clk				*adc_div_clk;
277 	struct clk_divider			clk_div;
278 	struct completion			done;
279 	int					calibbias;
280 	int					calibscale;
281 	struct regmap				*tsc_regmap;
282 	bool					temperature_sensor_calibrated;
283 	u8					temperature_sensor_coefficient;
284 	u16					temperature_sensor_adc_val;
285 };
286 
287 static const struct regmap_config meson_sar_adc_regmap_config_gxbb = {
288 	.reg_bits = 8,
289 	.val_bits = 32,
290 	.reg_stride = 4,
291 	.max_register = MESON_SAR_ADC_REG13,
292 };
293 
294 static const struct regmap_config meson_sar_adc_regmap_config_meson8 = {
295 	.reg_bits = 8,
296 	.val_bits = 32,
297 	.reg_stride = 4,
298 	.max_register = MESON_SAR_ADC_DELTA_10,
299 };
300 
301 static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev)
302 {
303 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
304 	u32 regval;
305 
306 	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
307 
308 	return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
309 }
310 
311 static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val)
312 {
313 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
314 	int tmp;
315 
316 	/* use val_calib = scale * val_raw + offset calibration function */
317 	tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
318 
319 	return clamp(tmp, 0, (1 << priv->param->resolution) - 1);
320 }
321 
322 static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev)
323 {
324 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
325 	int val;
326 
327 	/*
328 	 * NOTE: we need a small delay before reading the status, otherwise
329 	 * the sample engine may not have started internally (which would
330 	 * seem to us that sampling is already finished).
331 	 */
332 	udelay(1);
333 	return regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_REG0, val,
334 					       !FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, val),
335 					       1, 10000);
336 }
337 
338 static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
339 					 const struct iio_chan_spec *chan,
340 					 int *val)
341 {
342 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
343 	struct device *dev = indio_dev->dev.parent;
344 	int regval, fifo_chan, fifo_val, count;
345 
346 	if (!wait_for_completion_timeout(&priv->done,
347 				msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
348 		return -ETIMEDOUT;
349 
350 	count = meson_sar_adc_get_fifo_count(indio_dev);
351 	if (count != 1) {
352 		dev_err(dev, "ADC FIFO has %d element(s) instead of one\n", count);
353 		return -EINVAL;
354 	}
355 
356 	regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
357 	fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
358 	if (fifo_chan != chan->address) {
359 		dev_err(dev, "ADC FIFO entry belongs to channel %d instead of %lu\n",
360 			fifo_chan, chan->address);
361 		return -EINVAL;
362 	}
363 
364 	fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
365 	fifo_val &= GENMASK(priv->param->resolution - 1, 0);
366 	*val = meson_sar_adc_calib_val(indio_dev, fifo_val);
367 
368 	return 0;
369 }
370 
371 static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev,
372 					const struct iio_chan_spec *chan,
373 					enum meson_sar_adc_avg_mode mode,
374 					enum meson_sar_adc_num_samples samples)
375 {
376 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
377 	int val, address = chan->address;
378 
379 	val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(address);
380 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
381 			   MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(address),
382 			   val);
383 
384 	val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(address);
385 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
386 			   MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(address), val);
387 }
388 
389 static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev,
390 					const struct iio_chan_spec *chan)
391 {
392 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
393 	u32 regval;
394 
395 	/*
396 	 * the SAR ADC engine allows sampling multiple channels at the same
397 	 * time. to keep it simple we're only working with one *internal*
398 	 * channel, which starts counting at index 0 (which means: count = 1).
399 	 */
400 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
401 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
402 			   MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
403 
404 	/* map channel index 0 to the channel which we want to read */
405 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0),
406 			    chan->address);
407 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
408 			   MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
409 
410 	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
411 			    chan->address);
412 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
413 			   MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
414 			   regval);
415 
416 	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
417 			    chan->address);
418 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
419 			   MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
420 			   regval);
421 
422 	if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL) {
423 		if (chan->type == IIO_TEMP)
424 			regval = MESON_SAR_ADC_DELTA_10_TEMP_SEL;
425 		else
426 			regval = 0;
427 
428 		regmap_update_bits(priv->regmap,
429 				   MESON_SAR_ADC_DELTA_10,
430 				   MESON_SAR_ADC_DELTA_10_TEMP_SEL, regval);
431 	}
432 }
433 
434 static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev,
435 					enum meson_sar_adc_chan7_mux_sel sel)
436 {
437 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
438 	u32 regval;
439 
440 	regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
441 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
442 			   MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
443 
444 	usleep_range(10, 20);
445 }
446 
447 static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
448 {
449 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
450 
451 	reinit_completion(&priv->done);
452 
453 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
454 			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
455 			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
456 
457 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
458 			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
459 			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
460 
461 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
462 			   MESON_SAR_ADC_REG0_SAMPLING_START,
463 			   MESON_SAR_ADC_REG0_SAMPLING_START);
464 }
465 
466 static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
467 {
468 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
469 
470 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
471 			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
472 
473 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
474 			   MESON_SAR_ADC_REG0_SAMPLING_STOP,
475 			   MESON_SAR_ADC_REG0_SAMPLING_STOP);
476 
477 	/* wait until all modules are stopped */
478 	meson_sar_adc_wait_busy_clear(indio_dev);
479 
480 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
481 			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0);
482 }
483 
484 static int meson_sar_adc_lock(struct iio_dev *indio_dev)
485 {
486 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
487 	int val, ret;
488 
489 	mutex_lock(&indio_dev->mlock);
490 
491 	if (priv->param->has_bl30_integration) {
492 		/* prevent BL30 from using the SAR ADC while we are using it */
493 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
494 				   MESON_SAR_ADC_DELAY_KERNEL_BUSY,
495 				   MESON_SAR_ADC_DELAY_KERNEL_BUSY);
496 
497 		udelay(1);
498 
499 		/*
500 		 * wait until BL30 releases it's lock (so we can use the SAR
501 		 * ADC)
502 		 */
503 		ret = regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_DELAY, val,
504 						      !(val & MESON_SAR_ADC_DELAY_BL30_BUSY),
505 						      1, 10000);
506 		if (ret) {
507 			mutex_unlock(&indio_dev->mlock);
508 			return ret;
509 		}
510 	}
511 
512 	return 0;
513 }
514 
515 static void meson_sar_adc_unlock(struct iio_dev *indio_dev)
516 {
517 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
518 
519 	if (priv->param->has_bl30_integration)
520 		/* allow BL30 to use the SAR ADC again */
521 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
522 				   MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0);
523 
524 	mutex_unlock(&indio_dev->mlock);
525 }
526 
527 static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev)
528 {
529 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
530 	unsigned int count, tmp;
531 
532 	for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
533 		if (!meson_sar_adc_get_fifo_count(indio_dev))
534 			break;
535 
536 		regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
537 	}
538 }
539 
540 static int meson_sar_adc_get_sample(struct iio_dev *indio_dev,
541 				    const struct iio_chan_spec *chan,
542 				    enum meson_sar_adc_avg_mode avg_mode,
543 				    enum meson_sar_adc_num_samples avg_samples,
544 				    int *val)
545 {
546 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
547 	struct device *dev = indio_dev->dev.parent;
548 	int ret;
549 
550 	if (chan->type == IIO_TEMP && !priv->temperature_sensor_calibrated)
551 		return -ENOTSUPP;
552 
553 	ret = meson_sar_adc_lock(indio_dev);
554 	if (ret)
555 		return ret;
556 
557 	/* clear the FIFO to make sure we're not reading old values */
558 	meson_sar_adc_clear_fifo(indio_dev);
559 
560 	meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples);
561 
562 	meson_sar_adc_enable_channel(indio_dev, chan);
563 
564 	meson_sar_adc_start_sample_engine(indio_dev);
565 	ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val);
566 	meson_sar_adc_stop_sample_engine(indio_dev);
567 
568 	meson_sar_adc_unlock(indio_dev);
569 
570 	if (ret) {
571 		dev_warn(dev, "failed to read sample for channel %lu: %d\n",
572 			 chan->address, ret);
573 		return ret;
574 	}
575 
576 	return IIO_VAL_INT;
577 }
578 
579 static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev,
580 					   const struct iio_chan_spec *chan,
581 					   int *val, int *val2, long mask)
582 {
583 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
584 	struct device *dev = indio_dev->dev.parent;
585 	int ret;
586 
587 	switch (mask) {
588 	case IIO_CHAN_INFO_RAW:
589 		return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING,
590 						ONE_SAMPLE, val);
591 
592 	case IIO_CHAN_INFO_AVERAGE_RAW:
593 		return meson_sar_adc_get_sample(indio_dev, chan,
594 						MEAN_AVERAGING, EIGHT_SAMPLES,
595 						val);
596 
597 	case IIO_CHAN_INFO_SCALE:
598 		if (chan->type == IIO_VOLTAGE) {
599 			ret = regulator_get_voltage(priv->vref);
600 			if (ret < 0) {
601 				dev_err(dev, "failed to get vref voltage: %d\n", ret);
602 				return ret;
603 			}
604 
605 			*val = ret / 1000;
606 			*val2 = priv->param->resolution;
607 			return IIO_VAL_FRACTIONAL_LOG2;
608 		} else if (chan->type == IIO_TEMP) {
609 			/* SoC specific multiplier and divider */
610 			*val = priv->param->temperature_multiplier;
611 			*val2 = priv->param->temperature_divider;
612 
613 			/* celsius to millicelsius */
614 			*val *= 1000;
615 
616 			return IIO_VAL_FRACTIONAL;
617 		} else {
618 			return -EINVAL;
619 		}
620 
621 	case IIO_CHAN_INFO_CALIBBIAS:
622 		*val = priv->calibbias;
623 		return IIO_VAL_INT;
624 
625 	case IIO_CHAN_INFO_CALIBSCALE:
626 		*val = priv->calibscale / MILLION;
627 		*val2 = priv->calibscale % MILLION;
628 		return IIO_VAL_INT_PLUS_MICRO;
629 
630 	case IIO_CHAN_INFO_OFFSET:
631 		*val = DIV_ROUND_CLOSEST(MESON_SAR_ADC_TEMP_OFFSET *
632 					 priv->param->temperature_divider,
633 					 priv->param->temperature_multiplier);
634 		*val -= priv->temperature_sensor_adc_val;
635 		return IIO_VAL_INT;
636 
637 	default:
638 		return -EINVAL;
639 	}
640 }
641 
642 static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
643 				  void __iomem *base)
644 {
645 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
646 	struct device *dev = indio_dev->dev.parent;
647 	struct clk_init_data init;
648 	const char *clk_parents[1];
649 
650 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_div", dev_name(dev));
651 	if (!init.name)
652 		return -ENOMEM;
653 
654 	init.flags = 0;
655 	init.ops = &clk_divider_ops;
656 	clk_parents[0] = __clk_get_name(priv->clkin);
657 	init.parent_names = clk_parents;
658 	init.num_parents = 1;
659 
660 	priv->clk_div.reg = base + MESON_SAR_ADC_REG3;
661 	priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT;
662 	priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH;
663 	priv->clk_div.hw.init = &init;
664 	priv->clk_div.flags = 0;
665 
666 	priv->adc_div_clk = devm_clk_register(dev, &priv->clk_div.hw);
667 	if (WARN_ON(IS_ERR(priv->adc_div_clk)))
668 		return PTR_ERR(priv->adc_div_clk);
669 
670 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_en", dev_name(dev));
671 	if (!init.name)
672 		return -ENOMEM;
673 
674 	init.flags = CLK_SET_RATE_PARENT;
675 	init.ops = &clk_gate_ops;
676 	clk_parents[0] = __clk_get_name(priv->adc_div_clk);
677 	init.parent_names = clk_parents;
678 	init.num_parents = 1;
679 
680 	priv->clk_gate.reg = base + MESON_SAR_ADC_REG3;
681 	priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN);
682 	priv->clk_gate.hw.init = &init;
683 
684 	priv->adc_clk = devm_clk_register(dev, &priv->clk_gate.hw);
685 	if (WARN_ON(IS_ERR(priv->adc_clk)))
686 		return PTR_ERR(priv->adc_clk);
687 
688 	return 0;
689 }
690 
691 static int meson_sar_adc_temp_sensor_init(struct iio_dev *indio_dev)
692 {
693 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
694 	u8 *buf, trimming_bits, trimming_mask, upper_adc_val;
695 	struct device *dev = indio_dev->dev.parent;
696 	struct nvmem_cell *temperature_calib;
697 	size_t read_len;
698 	int ret;
699 
700 	temperature_calib = devm_nvmem_cell_get(dev, "temperature_calib");
701 	if (IS_ERR(temperature_calib)) {
702 		ret = PTR_ERR(temperature_calib);
703 
704 		/*
705 		 * leave the temperature sensor disabled if no calibration data
706 		 * was passed via nvmem-cells.
707 		 */
708 		if (ret == -ENODEV)
709 			return 0;
710 
711 		return dev_err_probe(dev, ret, "failed to get temperature_calib cell\n");
712 	}
713 
714 	priv->tsc_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "amlogic,hhi-sysctrl");
715 	if (IS_ERR(priv->tsc_regmap))
716 		return dev_err_probe(dev, PTR_ERR(priv->tsc_regmap),
717 				     "failed to get amlogic,hhi-sysctrl regmap\n");
718 
719 	read_len = MESON_SAR_ADC_EFUSE_BYTES;
720 	buf = nvmem_cell_read(temperature_calib, &read_len);
721 	if (IS_ERR(buf))
722 		return dev_err_probe(dev, PTR_ERR(buf), "failed to read temperature_calib cell\n");
723 	if (read_len != MESON_SAR_ADC_EFUSE_BYTES) {
724 		kfree(buf);
725 		return dev_err_probe(dev, -EINVAL, "invalid read size of temperature_calib cell\n");
726 	}
727 
728 	trimming_bits = priv->param->temperature_trimming_bits;
729 	trimming_mask = BIT(trimming_bits) - 1;
730 
731 	priv->temperature_sensor_calibrated =
732 		buf[3] & MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED;
733 	priv->temperature_sensor_coefficient = buf[2] & trimming_mask;
734 
735 	upper_adc_val = FIELD_GET(MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL,
736 				  buf[3]);
737 
738 	priv->temperature_sensor_adc_val = buf[2];
739 	priv->temperature_sensor_adc_val |= upper_adc_val << BITS_PER_BYTE;
740 	priv->temperature_sensor_adc_val >>= trimming_bits;
741 
742 	kfree(buf);
743 
744 	return 0;
745 }
746 
747 static int meson_sar_adc_init(struct iio_dev *indio_dev)
748 {
749 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
750 	struct device *dev = indio_dev->dev.parent;
751 	int regval, i, ret;
752 
753 	/*
754 	 * make sure we start at CH7 input since the other muxes are only used
755 	 * for internal calibration.
756 	 */
757 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
758 
759 	if (priv->param->has_bl30_integration) {
760 		/*
761 		 * leave sampling delay and the input clocks as configured by
762 		 * BL30 to make sure BL30 gets the values it expects when
763 		 * reading the temperature sensor.
764 		 */
765 		regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
766 		if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED)
767 			return 0;
768 	}
769 
770 	meson_sar_adc_stop_sample_engine(indio_dev);
771 
772 	/*
773 	 * disable this bit as seems to be only relevant for Meson6 (based
774 	 * on the vendor driver), which we don't support at the moment.
775 	 */
776 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
777 			   MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 0);
778 
779 	/* disable all channels by default */
780 	regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
781 
782 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
783 			   MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0);
784 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
785 			   MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY,
786 			   MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
787 
788 	/* delay between two samples = (10+1) * 1uS */
789 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
790 			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
791 			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
792 				      10));
793 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
794 			   MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
795 			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
796 				      0));
797 
798 	/* delay between two samples = (10+1) * 1uS */
799 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
800 			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
801 			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
802 				      10));
803 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
804 			   MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
805 			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
806 				      1));
807 
808 	/*
809 	 * set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
810 	 * (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
811 	 */
812 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
813 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
814 			   MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
815 			   regval);
816 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
817 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
818 			   MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
819 			   regval);
820 
821 	/*
822 	 * set up the input channel muxes in MESON_SAR_ADC_AUX_SW
823 	 * (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
824 	 * MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
825 	 * MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
826 	 */
827 	regval = 0;
828 	for (i = 2; i <= 7; i++)
829 		regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
830 	regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
831 	regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
832 	regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
833 
834 	if (priv->temperature_sensor_calibrated) {
835 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
836 				   MESON_SAR_ADC_DELTA_10_TS_REVE1,
837 				   MESON_SAR_ADC_DELTA_10_TS_REVE1);
838 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
839 				   MESON_SAR_ADC_DELTA_10_TS_REVE0,
840 				   MESON_SAR_ADC_DELTA_10_TS_REVE0);
841 
842 		/*
843 		 * set bits [3:0] of the TSC (temperature sensor coefficient)
844 		 * to get the correct values when reading the temperature.
845 		 */
846 		regval = FIELD_PREP(MESON_SAR_ADC_DELTA_10_TS_C_MASK,
847 				    priv->temperature_sensor_coefficient);
848 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
849 				   MESON_SAR_ADC_DELTA_10_TS_C_MASK, regval);
850 
851 		if (priv->param->temperature_trimming_bits == 5) {
852 			if (priv->temperature_sensor_coefficient & BIT(4))
853 				regval = MESON_HHI_DPLL_TOP_0_TSC_BIT4;
854 			else
855 				regval = 0;
856 
857 			/*
858 			 * bit [4] (the 5th bit when starting to count at 1)
859 			 * of the TSC is located in the HHI register area.
860 			 */
861 			regmap_update_bits(priv->tsc_regmap,
862 					   MESON_HHI_DPLL_TOP_0,
863 					   MESON_HHI_DPLL_TOP_0_TSC_BIT4,
864 					   regval);
865 		}
866 	} else {
867 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
868 				   MESON_SAR_ADC_DELTA_10_TS_REVE1, 0);
869 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
870 				   MESON_SAR_ADC_DELTA_10_TS_REVE0, 0);
871 	}
872 
873 	ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
874 	if (ret)
875 		return dev_err_probe(dev, ret, "failed to set adc parent to clkin\n");
876 
877 	ret = clk_set_rate(priv->adc_clk, priv->param->clock_rate);
878 	if (ret)
879 		return dev_err_probe(dev, ret, "failed to set adc clock rate\n");
880 
881 	return 0;
882 }
883 
884 static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off)
885 {
886 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
887 	const struct meson_sar_adc_param *param = priv->param;
888 	u32 enable_mask;
889 
890 	if (param->bandgap_reg == MESON_SAR_ADC_REG11)
891 		enable_mask = MESON_SAR_ADC_REG11_BANDGAP_EN;
892 	else
893 		enable_mask = MESON_SAR_ADC_DELTA_10_TS_VBG_EN;
894 
895 	regmap_update_bits(priv->regmap, param->bandgap_reg, enable_mask,
896 			   on_off ? enable_mask : 0);
897 }
898 
899 static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
900 {
901 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
902 	struct device *dev = indio_dev->dev.parent;
903 	int ret;
904 	u32 regval;
905 
906 	ret = meson_sar_adc_lock(indio_dev);
907 	if (ret)
908 		goto err_lock;
909 
910 	ret = regulator_enable(priv->vref);
911 	if (ret < 0) {
912 		dev_err(dev, "failed to enable vref regulator\n");
913 		goto err_vref;
914 	}
915 
916 	ret = clk_prepare_enable(priv->core_clk);
917 	if (ret) {
918 		dev_err(dev, "failed to enable core clk\n");
919 		goto err_core_clk;
920 	}
921 
922 	regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
923 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
924 			   MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
925 
926 	meson_sar_adc_set_bandgap(indio_dev, true);
927 
928 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
929 			   MESON_SAR_ADC_REG3_ADC_EN,
930 			   MESON_SAR_ADC_REG3_ADC_EN);
931 
932 	udelay(5);
933 
934 	ret = clk_prepare_enable(priv->adc_clk);
935 	if (ret) {
936 		dev_err(dev, "failed to enable adc clk\n");
937 		goto err_adc_clk;
938 	}
939 
940 	meson_sar_adc_unlock(indio_dev);
941 
942 	return 0;
943 
944 err_adc_clk:
945 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
946 			   MESON_SAR_ADC_REG3_ADC_EN, 0);
947 	meson_sar_adc_set_bandgap(indio_dev, false);
948 	clk_disable_unprepare(priv->core_clk);
949 err_core_clk:
950 	regulator_disable(priv->vref);
951 err_vref:
952 	meson_sar_adc_unlock(indio_dev);
953 err_lock:
954 	return ret;
955 }
956 
957 static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
958 {
959 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
960 	int ret;
961 
962 	ret = meson_sar_adc_lock(indio_dev);
963 	if (ret)
964 		return ret;
965 
966 	clk_disable_unprepare(priv->adc_clk);
967 
968 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
969 			   MESON_SAR_ADC_REG3_ADC_EN, 0);
970 
971 	meson_sar_adc_set_bandgap(indio_dev, false);
972 
973 	clk_disable_unprepare(priv->core_clk);
974 
975 	regulator_disable(priv->vref);
976 
977 	meson_sar_adc_unlock(indio_dev);
978 
979 	return 0;
980 }
981 
982 static irqreturn_t meson_sar_adc_irq(int irq, void *data)
983 {
984 	struct iio_dev *indio_dev = data;
985 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
986 	unsigned int cnt, threshold;
987 	u32 regval;
988 
989 	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
990 	cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
991 	threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
992 
993 	if (cnt < threshold)
994 		return IRQ_NONE;
995 
996 	complete(&priv->done);
997 
998 	return IRQ_HANDLED;
999 }
1000 
1001 static int meson_sar_adc_calib(struct iio_dev *indio_dev)
1002 {
1003 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1004 	int ret, nominal0, nominal1, value0, value1;
1005 
1006 	/* use points 25% and 75% for calibration */
1007 	nominal0 = (1 << priv->param->resolution) / 4;
1008 	nominal1 = (1 << priv->param->resolution) * 3 / 4;
1009 
1010 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4);
1011 	usleep_range(10, 20);
1012 	ret = meson_sar_adc_get_sample(indio_dev,
1013 				       &indio_dev->channels[7],
1014 				       MEAN_AVERAGING, EIGHT_SAMPLES, &value0);
1015 	if (ret < 0)
1016 		goto out;
1017 
1018 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4);
1019 	usleep_range(10, 20);
1020 	ret = meson_sar_adc_get_sample(indio_dev,
1021 				       &indio_dev->channels[7],
1022 				       MEAN_AVERAGING, EIGHT_SAMPLES, &value1);
1023 	if (ret < 0)
1024 		goto out;
1025 
1026 	if (value1 <= value0) {
1027 		ret = -EINVAL;
1028 		goto out;
1029 	}
1030 
1031 	priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
1032 				   value1 - value0);
1033 	priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
1034 					     MILLION);
1035 	ret = 0;
1036 out:
1037 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
1038 
1039 	return ret;
1040 }
1041 
1042 static const struct iio_info meson_sar_adc_iio_info = {
1043 	.read_raw = meson_sar_adc_iio_info_read_raw,
1044 };
1045 
1046 static const struct meson_sar_adc_param meson_sar_adc_meson8_param = {
1047 	.has_bl30_integration = false,
1048 	.clock_rate = 1150000,
1049 	.bandgap_reg = MESON_SAR_ADC_DELTA_10,
1050 	.regmap_config = &meson_sar_adc_regmap_config_meson8,
1051 	.resolution = 10,
1052 	.temperature_trimming_bits = 4,
1053 	.temperature_multiplier = 18 * 10000,
1054 	.temperature_divider = 1024 * 10 * 85,
1055 };
1056 
1057 static const struct meson_sar_adc_param meson_sar_adc_meson8b_param = {
1058 	.has_bl30_integration = false,
1059 	.clock_rate = 1150000,
1060 	.bandgap_reg = MESON_SAR_ADC_DELTA_10,
1061 	.regmap_config = &meson_sar_adc_regmap_config_meson8,
1062 	.resolution = 10,
1063 	.temperature_trimming_bits = 5,
1064 	.temperature_multiplier = 10,
1065 	.temperature_divider = 32,
1066 };
1067 
1068 static const struct meson_sar_adc_param meson_sar_adc_gxbb_param = {
1069 	.has_bl30_integration = true,
1070 	.clock_rate = 1200000,
1071 	.bandgap_reg = MESON_SAR_ADC_REG11,
1072 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1073 	.resolution = 10,
1074 };
1075 
1076 static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
1077 	.has_bl30_integration = true,
1078 	.clock_rate = 1200000,
1079 	.bandgap_reg = MESON_SAR_ADC_REG11,
1080 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1081 	.resolution = 12,
1082 };
1083 
1084 static const struct meson_sar_adc_param meson_sar_adc_g12a_param = {
1085 	.has_bl30_integration = false,
1086 	.clock_rate = 1200000,
1087 	.bandgap_reg = MESON_SAR_ADC_REG11,
1088 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1089 	.resolution = 12,
1090 };
1091 
1092 static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
1093 	.param = &meson_sar_adc_meson8_param,
1094 	.name = "meson-meson8-saradc",
1095 };
1096 
1097 static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
1098 	.param = &meson_sar_adc_meson8b_param,
1099 	.name = "meson-meson8b-saradc",
1100 };
1101 
1102 static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
1103 	.param = &meson_sar_adc_meson8b_param,
1104 	.name = "meson-meson8m2-saradc",
1105 };
1106 
1107 static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
1108 	.param = &meson_sar_adc_gxbb_param,
1109 	.name = "meson-gxbb-saradc",
1110 };
1111 
1112 static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
1113 	.param = &meson_sar_adc_gxl_param,
1114 	.name = "meson-gxl-saradc",
1115 };
1116 
1117 static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
1118 	.param = &meson_sar_adc_gxl_param,
1119 	.name = "meson-gxm-saradc",
1120 };
1121 
1122 static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
1123 	.param = &meson_sar_adc_gxl_param,
1124 	.name = "meson-axg-saradc",
1125 };
1126 
1127 static const struct meson_sar_adc_data meson_sar_adc_g12a_data = {
1128 	.param = &meson_sar_adc_g12a_param,
1129 	.name = "meson-g12a-saradc",
1130 };
1131 
1132 static const struct of_device_id meson_sar_adc_of_match[] = {
1133 	{
1134 		.compatible = "amlogic,meson8-saradc",
1135 		.data = &meson_sar_adc_meson8_data,
1136 	}, {
1137 		.compatible = "amlogic,meson8b-saradc",
1138 		.data = &meson_sar_adc_meson8b_data,
1139 	}, {
1140 		.compatible = "amlogic,meson8m2-saradc",
1141 		.data = &meson_sar_adc_meson8m2_data,
1142 	}, {
1143 		.compatible = "amlogic,meson-gxbb-saradc",
1144 		.data = &meson_sar_adc_gxbb_data,
1145 	}, {
1146 		.compatible = "amlogic,meson-gxl-saradc",
1147 		.data = &meson_sar_adc_gxl_data,
1148 	}, {
1149 		.compatible = "amlogic,meson-gxm-saradc",
1150 		.data = &meson_sar_adc_gxm_data,
1151 	}, {
1152 		.compatible = "amlogic,meson-axg-saradc",
1153 		.data = &meson_sar_adc_axg_data,
1154 	}, {
1155 		.compatible = "amlogic,meson-g12a-saradc",
1156 		.data = &meson_sar_adc_g12a_data,
1157 	},
1158 	{ /* sentinel */ }
1159 };
1160 MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match);
1161 
1162 static int meson_sar_adc_probe(struct platform_device *pdev)
1163 {
1164 	const struct meson_sar_adc_data *match_data;
1165 	struct meson_sar_adc_priv *priv;
1166 	struct device *dev = &pdev->dev;
1167 	struct iio_dev *indio_dev;
1168 	void __iomem *base;
1169 	int irq, ret;
1170 
1171 	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
1172 	if (!indio_dev)
1173 		return dev_err_probe(dev, -ENOMEM, "failed allocating iio device\n");
1174 
1175 	priv = iio_priv(indio_dev);
1176 	init_completion(&priv->done);
1177 
1178 	match_data = of_device_get_match_data(dev);
1179 	if (!match_data)
1180 		return dev_err_probe(dev, -ENODEV, "failed to get match data\n");
1181 
1182 	priv->param = match_data->param;
1183 
1184 	indio_dev->name = match_data->name;
1185 	indio_dev->modes = INDIO_DIRECT_MODE;
1186 	indio_dev->info = &meson_sar_adc_iio_info;
1187 
1188 	base = devm_platform_ioremap_resource(pdev, 0);
1189 	if (IS_ERR(base))
1190 		return PTR_ERR(base);
1191 
1192 	priv->regmap = devm_regmap_init_mmio(dev, base, priv->param->regmap_config);
1193 	if (IS_ERR(priv->regmap))
1194 		return PTR_ERR(priv->regmap);
1195 
1196 	irq = irq_of_parse_and_map(dev->of_node, 0);
1197 	if (!irq)
1198 		return -EINVAL;
1199 
1200 	ret = devm_request_irq(dev, irq, meson_sar_adc_irq, IRQF_SHARED, dev_name(dev), indio_dev);
1201 	if (ret)
1202 		return ret;
1203 
1204 	priv->clkin = devm_clk_get(dev, "clkin");
1205 	if (IS_ERR(priv->clkin))
1206 		return dev_err_probe(dev, PTR_ERR(priv->clkin), "failed to get clkin\n");
1207 
1208 	priv->core_clk = devm_clk_get(dev, "core");
1209 	if (IS_ERR(priv->core_clk))
1210 		return dev_err_probe(dev, PTR_ERR(priv->core_clk), "failed to get core clk\n");
1211 
1212 	priv->adc_clk = devm_clk_get_optional(dev, "adc_clk");
1213 	if (IS_ERR(priv->adc_clk))
1214 		return dev_err_probe(dev, PTR_ERR(priv->adc_clk), "failed to get adc clk\n");
1215 
1216 	priv->adc_sel_clk = devm_clk_get_optional(dev, "adc_sel");
1217 	if (IS_ERR(priv->adc_sel_clk))
1218 		return dev_err_probe(dev, PTR_ERR(priv->adc_sel_clk), "failed to get adc_sel clk\n");
1219 
1220 	/* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */
1221 	if (!priv->adc_clk) {
1222 		ret = meson_sar_adc_clk_init(indio_dev, base);
1223 		if (ret)
1224 			return ret;
1225 	}
1226 
1227 	priv->vref = devm_regulator_get(dev, "vref");
1228 	if (IS_ERR(priv->vref))
1229 		return dev_err_probe(dev, PTR_ERR(priv->vref), "failed to get vref regulator\n");
1230 
1231 	priv->calibscale = MILLION;
1232 
1233 	if (priv->param->temperature_trimming_bits) {
1234 		ret = meson_sar_adc_temp_sensor_init(indio_dev);
1235 		if (ret)
1236 			return ret;
1237 	}
1238 
1239 	if (priv->temperature_sensor_calibrated) {
1240 		indio_dev->channels = meson_sar_adc_and_temp_iio_channels;
1241 		indio_dev->num_channels =
1242 			ARRAY_SIZE(meson_sar_adc_and_temp_iio_channels);
1243 	} else {
1244 		indio_dev->channels = meson_sar_adc_iio_channels;
1245 		indio_dev->num_channels =
1246 			ARRAY_SIZE(meson_sar_adc_iio_channels);
1247 	}
1248 
1249 	ret = meson_sar_adc_init(indio_dev);
1250 	if (ret)
1251 		goto err;
1252 
1253 	ret = meson_sar_adc_hw_enable(indio_dev);
1254 	if (ret)
1255 		goto err;
1256 
1257 	ret = meson_sar_adc_calib(indio_dev);
1258 	if (ret)
1259 		dev_warn(dev, "calibration failed\n");
1260 
1261 	platform_set_drvdata(pdev, indio_dev);
1262 
1263 	ret = iio_device_register(indio_dev);
1264 	if (ret)
1265 		goto err_hw;
1266 
1267 	return 0;
1268 
1269 err_hw:
1270 	meson_sar_adc_hw_disable(indio_dev);
1271 err:
1272 	return ret;
1273 }
1274 
1275 static int meson_sar_adc_remove(struct platform_device *pdev)
1276 {
1277 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
1278 
1279 	iio_device_unregister(indio_dev);
1280 
1281 	return meson_sar_adc_hw_disable(indio_dev);
1282 }
1283 
1284 static int meson_sar_adc_suspend(struct device *dev)
1285 {
1286 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1287 
1288 	return meson_sar_adc_hw_disable(indio_dev);
1289 }
1290 
1291 static int meson_sar_adc_resume(struct device *dev)
1292 {
1293 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1294 
1295 	return meson_sar_adc_hw_enable(indio_dev);
1296 }
1297 
1298 static DEFINE_SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops,
1299 				meson_sar_adc_suspend, meson_sar_adc_resume);
1300 
1301 static struct platform_driver meson_sar_adc_driver = {
1302 	.probe		= meson_sar_adc_probe,
1303 	.remove		= meson_sar_adc_remove,
1304 	.driver		= {
1305 		.name	= "meson-saradc",
1306 		.of_match_table = meson_sar_adc_of_match,
1307 		.pm = pm_sleep_ptr(&meson_sar_adc_pm_ops),
1308 	},
1309 };
1310 
1311 module_platform_driver(meson_sar_adc_driver);
1312 
1313 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
1314 MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver");
1315 MODULE_LICENSE("GPL v2");
1316