xref: /openbmc/linux/drivers/iio/adc/meson_saradc.c (revision 703e7713)
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/mutex.h>
16 #include <linux/nvmem-consumer.h>
17 #include <linux/interrupt.h>
18 #include <linux/of.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_device.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/mfd/syscon.h>
25 
26 #define MESON_SAR_ADC_REG0					0x00
27 	#define MESON_SAR_ADC_REG0_PANEL_DETECT			BIT(31)
28 	#define MESON_SAR_ADC_REG0_BUSY_MASK			GENMASK(30, 28)
29 	#define MESON_SAR_ADC_REG0_DELTA_BUSY			BIT(30)
30 	#define MESON_SAR_ADC_REG0_AVG_BUSY			BIT(29)
31 	#define MESON_SAR_ADC_REG0_SAMPLE_BUSY			BIT(28)
32 	#define MESON_SAR_ADC_REG0_FIFO_FULL			BIT(27)
33 	#define MESON_SAR_ADC_REG0_FIFO_EMPTY			BIT(26)
34 	#define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK		GENMASK(25, 21)
35 	#define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK		GENMASK(20, 19)
36 	#define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK		GENMASK(18, 16)
37 	#define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL		BIT(15)
38 	#define MESON_SAR_ADC_REG0_SAMPLING_STOP		BIT(14)
39 	#define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK		GENMASK(13, 12)
40 	#define MESON_SAR_ADC_REG0_DETECT_IRQ_POL		BIT(10)
41 	#define MESON_SAR_ADC_REG0_DETECT_IRQ_EN		BIT(9)
42 	#define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK		GENMASK(8, 4)
43 	#define MESON_SAR_ADC_REG0_FIFO_IRQ_EN			BIT(3)
44 	#define MESON_SAR_ADC_REG0_SAMPLING_START		BIT(2)
45 	#define MESON_SAR_ADC_REG0_CONTINUOUS_EN		BIT(1)
46 	#define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE		BIT(0)
47 
48 #define MESON_SAR_ADC_CHAN_LIST					0x04
49 	#define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK		GENMASK(26, 24)
50 	#define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan)	\
51 					(GENMASK(2, 0) << ((_chan) * 3))
52 
53 #define MESON_SAR_ADC_AVG_CNTL					0x08
54 	#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan)	\
55 					(16 + ((_chan) * 2))
56 	#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan)	\
57 					(GENMASK(17, 16) << ((_chan) * 2))
58 	#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan)	\
59 					(0 + ((_chan) * 2))
60 	#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan)	\
61 					(GENMASK(1, 0) << ((_chan) * 2))
62 
63 #define MESON_SAR_ADC_REG3					0x0c
64 	#define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY		BIT(31)
65 	#define MESON_SAR_ADC_REG3_CLK_EN			BIT(30)
66 	#define MESON_SAR_ADC_REG3_BL30_INITIALIZED		BIT(28)
67 	#define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN	BIT(27)
68 	#define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE	BIT(26)
69 	#define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK	GENMASK(25, 23)
70 	#define MESON_SAR_ADC_REG3_DETECT_EN			BIT(22)
71 	#define MESON_SAR_ADC_REG3_ADC_EN			BIT(21)
72 	#define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK	GENMASK(20, 18)
73 	#define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK	GENMASK(17, 16)
74 	#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT		10
75 	#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH		6
76 	#define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK		GENMASK(9, 8)
77 	#define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK		GENMASK(7, 0)
78 
79 #define MESON_SAR_ADC_DELAY					0x10
80 	#define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK		GENMASK(25, 24)
81 	#define MESON_SAR_ADC_DELAY_BL30_BUSY			BIT(15)
82 	#define MESON_SAR_ADC_DELAY_KERNEL_BUSY			BIT(14)
83 	#define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK		GENMASK(23, 16)
84 	#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK		GENMASK(9, 8)
85 	#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK		GENMASK(7, 0)
86 
87 #define MESON_SAR_ADC_LAST_RD					0x14
88 	#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK	GENMASK(23, 16)
89 	#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK	GENMASK(9, 0)
90 
91 #define MESON_SAR_ADC_FIFO_RD					0x18
92 	#define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK		GENMASK(14, 12)
93 	#define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK		GENMASK(11, 0)
94 
95 #define MESON_SAR_ADC_AUX_SW					0x1c
96 	#define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan)	\
97 					(8 + (((_chan) - 2) * 3))
98 	#define MESON_SAR_ADC_AUX_SW_VREF_P_MUX			BIT(6)
99 	#define MESON_SAR_ADC_AUX_SW_VREF_N_MUX			BIT(5)
100 	#define MESON_SAR_ADC_AUX_SW_MODE_SEL			BIT(4)
101 	#define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW		BIT(3)
102 	#define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW		BIT(2)
103 	#define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW		BIT(1)
104 	#define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW		BIT(0)
105 
106 #define MESON_SAR_ADC_CHAN_10_SW				0x20
107 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK	GENMASK(25, 23)
108 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX	BIT(22)
109 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX	BIT(21)
110 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL		BIT(20)
111 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW	BIT(19)
112 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW	BIT(18)
113 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW	BIT(17)
114 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW	BIT(16)
115 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK	GENMASK(9, 7)
116 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX	BIT(6)
117 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX	BIT(5)
118 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL		BIT(4)
119 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW	BIT(3)
120 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW	BIT(2)
121 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW	BIT(1)
122 	#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW	BIT(0)
123 
124 #define MESON_SAR_ADC_DETECT_IDLE_SW				0x24
125 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN	BIT(26)
126 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK	GENMASK(25, 23)
127 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX	BIT(22)
128 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX	BIT(21)
129 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL	BIT(20)
130 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW	BIT(19)
131 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW	BIT(18)
132 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW	BIT(17)
133 	#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW	BIT(16)
134 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK	GENMASK(9, 7)
135 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX	BIT(6)
136 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX	BIT(5)
137 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL	BIT(4)
138 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW	BIT(3)
139 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW	BIT(2)
140 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW	BIT(1)
141 	#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW	BIT(0)
142 
143 #define MESON_SAR_ADC_DELTA_10					0x28
144 	#define MESON_SAR_ADC_DELTA_10_TEMP_SEL			BIT(27)
145 	#define MESON_SAR_ADC_DELTA_10_TS_REVE1			BIT(26)
146 	#define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK	GENMASK(25, 16)
147 	#define MESON_SAR_ADC_DELTA_10_TS_REVE0			BIT(15)
148 	#define MESON_SAR_ADC_DELTA_10_TS_C_MASK		GENMASK(14, 11)
149 	#define MESON_SAR_ADC_DELTA_10_TS_VBG_EN		BIT(10)
150 	#define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK	GENMASK(9, 0)
151 
152 /*
153  * NOTE: registers from here are undocumented (the vendor Linux kernel driver
154  * and u-boot source served as reference). These only seem to be relevant on
155  * GXBB and newer.
156  */
157 #define MESON_SAR_ADC_REG11					0x2c
158 	#define MESON_SAR_ADC_REG11_BANDGAP_EN			BIT(13)
159 
160 #define MESON_SAR_ADC_REG13					0x34
161 	#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK	GENMASK(13, 8)
162 
163 #define MESON_SAR_ADC_MAX_FIFO_SIZE				32
164 #define MESON_SAR_ADC_TIMEOUT					100 /* ms */
165 #define MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL			6
166 #define MESON_SAR_ADC_TEMP_OFFSET				27
167 
168 /* temperature sensor calibration information in eFuse */
169 #define MESON_SAR_ADC_EFUSE_BYTES				4
170 #define MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL			GENMASK(6, 0)
171 #define MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED			BIT(7)
172 
173 #define MESON_HHI_DPLL_TOP_0					0x318
174 #define MESON_HHI_DPLL_TOP_0_TSC_BIT4				BIT(9)
175 
176 /* for use with IIO_VAL_INT_PLUS_MICRO */
177 #define MILLION							1000000
178 
179 #define MESON_SAR_ADC_CHAN(_chan) {					\
180 	.type = IIO_VOLTAGE,						\
181 	.indexed = 1,							\
182 	.channel = _chan,						\
183 	.address = _chan,						\
184 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
185 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
186 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
187 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
188 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
189 	.datasheet_name = "SAR_ADC_CH"#_chan,				\
190 }
191 
192 #define MESON_SAR_ADC_TEMP_CHAN(_chan) {				\
193 	.type = IIO_TEMP,						\
194 	.channel = _chan,						\
195 	.address = MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL,		\
196 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
197 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
198 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |		\
199 					BIT(IIO_CHAN_INFO_SCALE),	\
200 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
201 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
202 	.datasheet_name = "TEMP_SENSOR",				\
203 }
204 
205 static const struct iio_chan_spec meson_sar_adc_iio_channels[] = {
206 	MESON_SAR_ADC_CHAN(0),
207 	MESON_SAR_ADC_CHAN(1),
208 	MESON_SAR_ADC_CHAN(2),
209 	MESON_SAR_ADC_CHAN(3),
210 	MESON_SAR_ADC_CHAN(4),
211 	MESON_SAR_ADC_CHAN(5),
212 	MESON_SAR_ADC_CHAN(6),
213 	MESON_SAR_ADC_CHAN(7),
214 	IIO_CHAN_SOFT_TIMESTAMP(8),
215 };
216 
217 static const struct iio_chan_spec meson_sar_adc_and_temp_iio_channels[] = {
218 	MESON_SAR_ADC_CHAN(0),
219 	MESON_SAR_ADC_CHAN(1),
220 	MESON_SAR_ADC_CHAN(2),
221 	MESON_SAR_ADC_CHAN(3),
222 	MESON_SAR_ADC_CHAN(4),
223 	MESON_SAR_ADC_CHAN(5),
224 	MESON_SAR_ADC_CHAN(6),
225 	MESON_SAR_ADC_CHAN(7),
226 	MESON_SAR_ADC_TEMP_CHAN(8),
227 	IIO_CHAN_SOFT_TIMESTAMP(9),
228 };
229 
230 enum meson_sar_adc_avg_mode {
231 	NO_AVERAGING = 0x0,
232 	MEAN_AVERAGING = 0x1,
233 	MEDIAN_AVERAGING = 0x2,
234 };
235 
236 enum meson_sar_adc_num_samples {
237 	ONE_SAMPLE = 0x0,
238 	TWO_SAMPLES = 0x1,
239 	FOUR_SAMPLES = 0x2,
240 	EIGHT_SAMPLES = 0x3,
241 };
242 
243 enum meson_sar_adc_chan7_mux_sel {
244 	CHAN7_MUX_VSS = 0x0,
245 	CHAN7_MUX_VDD_DIV4 = 0x1,
246 	CHAN7_MUX_VDD_DIV2 = 0x2,
247 	CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
248 	CHAN7_MUX_VDD = 0x4,
249 	CHAN7_MUX_CH7_INPUT = 0x7,
250 };
251 
252 struct meson_sar_adc_param {
253 	bool					has_bl30_integration;
254 	unsigned long				clock_rate;
255 	u32					bandgap_reg;
256 	unsigned int				resolution;
257 	const struct regmap_config		*regmap_config;
258 	u8					temperature_trimming_bits;
259 	unsigned int				temperature_multiplier;
260 	unsigned int				temperature_divider;
261 };
262 
263 struct meson_sar_adc_data {
264 	const struct meson_sar_adc_param	*param;
265 	const char				*name;
266 };
267 
268 struct meson_sar_adc_priv {
269 	struct regmap				*regmap;
270 	struct regulator			*vref;
271 	const struct meson_sar_adc_param	*param;
272 	struct clk				*clkin;
273 	struct clk				*core_clk;
274 	struct clk				*adc_sel_clk;
275 	struct clk				*adc_clk;
276 	struct clk_gate				clk_gate;
277 	struct clk				*adc_div_clk;
278 	struct clk_divider			clk_div;
279 	struct completion			done;
280 	/* lock to protect against multiple access to the device */
281 	struct mutex				lock;
282 	int					calibbias;
283 	int					calibscale;
284 	struct regmap				*tsc_regmap;
285 	bool					temperature_sensor_calibrated;
286 	u8					temperature_sensor_coefficient;
287 	u16					temperature_sensor_adc_val;
288 };
289 
290 static const struct regmap_config meson_sar_adc_regmap_config_gxbb = {
291 	.reg_bits = 8,
292 	.val_bits = 32,
293 	.reg_stride = 4,
294 	.max_register = MESON_SAR_ADC_REG13,
295 };
296 
297 static const struct regmap_config meson_sar_adc_regmap_config_meson8 = {
298 	.reg_bits = 8,
299 	.val_bits = 32,
300 	.reg_stride = 4,
301 	.max_register = MESON_SAR_ADC_DELTA_10,
302 };
303 
304 static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev)
305 {
306 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
307 	u32 regval;
308 
309 	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
310 
311 	return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
312 }
313 
314 static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val)
315 {
316 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
317 	int tmp;
318 
319 	/* use val_calib = scale * val_raw + offset calibration function */
320 	tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
321 
322 	return clamp(tmp, 0, (1 << priv->param->resolution) - 1);
323 }
324 
325 static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev)
326 {
327 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
328 	int val;
329 
330 	/*
331 	 * NOTE: we need a small delay before reading the status, otherwise
332 	 * the sample engine may not have started internally (which would
333 	 * seem to us that sampling is already finished).
334 	 */
335 	udelay(1);
336 	return regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_REG0, val,
337 					       !FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, val),
338 					       1, 10000);
339 }
340 
341 static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
342 					 const struct iio_chan_spec *chan,
343 					 int *val)
344 {
345 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
346 	struct device *dev = indio_dev->dev.parent;
347 	int regval, fifo_chan, fifo_val, count;
348 
349 	if (!wait_for_completion_timeout(&priv->done,
350 				msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
351 		return -ETIMEDOUT;
352 
353 	count = meson_sar_adc_get_fifo_count(indio_dev);
354 	if (count != 1) {
355 		dev_err(dev, "ADC FIFO has %d element(s) instead of one\n", count);
356 		return -EINVAL;
357 	}
358 
359 	regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
360 	fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
361 	if (fifo_chan != chan->address) {
362 		dev_err(dev, "ADC FIFO entry belongs to channel %d instead of %lu\n",
363 			fifo_chan, chan->address);
364 		return -EINVAL;
365 	}
366 
367 	fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
368 	fifo_val &= GENMASK(priv->param->resolution - 1, 0);
369 	*val = meson_sar_adc_calib_val(indio_dev, fifo_val);
370 
371 	return 0;
372 }
373 
374 static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev,
375 					const struct iio_chan_spec *chan,
376 					enum meson_sar_adc_avg_mode mode,
377 					enum meson_sar_adc_num_samples samples)
378 {
379 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
380 	int val, address = chan->address;
381 
382 	val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(address);
383 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
384 			   MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(address),
385 			   val);
386 
387 	val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(address);
388 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
389 			   MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(address), val);
390 }
391 
392 static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev,
393 					const struct iio_chan_spec *chan)
394 {
395 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
396 	u32 regval;
397 
398 	/*
399 	 * the SAR ADC engine allows sampling multiple channels at the same
400 	 * time. to keep it simple we're only working with one *internal*
401 	 * channel, which starts counting at index 0 (which means: count = 1).
402 	 */
403 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
404 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
405 			   MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
406 
407 	/* map channel index 0 to the channel which we want to read */
408 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0),
409 			    chan->address);
410 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
411 			   MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
412 
413 	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
414 			    chan->address);
415 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
416 			   MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
417 			   regval);
418 
419 	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
420 			    chan->address);
421 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
422 			   MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
423 			   regval);
424 
425 	if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL) {
426 		if (chan->type == IIO_TEMP)
427 			regval = MESON_SAR_ADC_DELTA_10_TEMP_SEL;
428 		else
429 			regval = 0;
430 
431 		regmap_update_bits(priv->regmap,
432 				   MESON_SAR_ADC_DELTA_10,
433 				   MESON_SAR_ADC_DELTA_10_TEMP_SEL, regval);
434 	}
435 }
436 
437 static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev,
438 					enum meson_sar_adc_chan7_mux_sel sel)
439 {
440 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
441 	u32 regval;
442 
443 	regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
444 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
445 			   MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
446 
447 	usleep_range(10, 20);
448 }
449 
450 static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
451 {
452 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
453 
454 	reinit_completion(&priv->done);
455 
456 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
457 			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
458 			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
459 
460 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
461 			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
462 			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
463 
464 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
465 			   MESON_SAR_ADC_REG0_SAMPLING_START,
466 			   MESON_SAR_ADC_REG0_SAMPLING_START);
467 }
468 
469 static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
470 {
471 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
472 
473 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
474 			   MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
475 
476 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
477 			   MESON_SAR_ADC_REG0_SAMPLING_STOP,
478 			   MESON_SAR_ADC_REG0_SAMPLING_STOP);
479 
480 	/* wait until all modules are stopped */
481 	meson_sar_adc_wait_busy_clear(indio_dev);
482 
483 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
484 			   MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0);
485 }
486 
487 static int meson_sar_adc_lock(struct iio_dev *indio_dev)
488 {
489 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
490 	int val, ret;
491 
492 	mutex_lock(&priv->lock);
493 
494 	if (priv->param->has_bl30_integration) {
495 		/* prevent BL30 from using the SAR ADC while we are using it */
496 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
497 				   MESON_SAR_ADC_DELAY_KERNEL_BUSY,
498 				   MESON_SAR_ADC_DELAY_KERNEL_BUSY);
499 
500 		udelay(1);
501 
502 		/*
503 		 * wait until BL30 releases it's lock (so we can use the SAR
504 		 * ADC)
505 		 */
506 		ret = regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_DELAY, val,
507 						      !(val & MESON_SAR_ADC_DELAY_BL30_BUSY),
508 						      1, 10000);
509 		if (ret) {
510 			mutex_unlock(&priv->lock);
511 			return ret;
512 		}
513 	}
514 
515 	return 0;
516 }
517 
518 static void meson_sar_adc_unlock(struct iio_dev *indio_dev)
519 {
520 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
521 
522 	if (priv->param->has_bl30_integration)
523 		/* allow BL30 to use the SAR ADC again */
524 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
525 				   MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0);
526 
527 	mutex_unlock(&priv->lock);
528 }
529 
530 static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev)
531 {
532 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
533 	unsigned int count, tmp;
534 
535 	for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
536 		if (!meson_sar_adc_get_fifo_count(indio_dev))
537 			break;
538 
539 		regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
540 	}
541 }
542 
543 static int meson_sar_adc_get_sample(struct iio_dev *indio_dev,
544 				    const struct iio_chan_spec *chan,
545 				    enum meson_sar_adc_avg_mode avg_mode,
546 				    enum meson_sar_adc_num_samples avg_samples,
547 				    int *val)
548 {
549 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
550 	struct device *dev = indio_dev->dev.parent;
551 	int ret;
552 
553 	if (chan->type == IIO_TEMP && !priv->temperature_sensor_calibrated)
554 		return -ENOTSUPP;
555 
556 	ret = meson_sar_adc_lock(indio_dev);
557 	if (ret)
558 		return ret;
559 
560 	/* clear the FIFO to make sure we're not reading old values */
561 	meson_sar_adc_clear_fifo(indio_dev);
562 
563 	meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples);
564 
565 	meson_sar_adc_enable_channel(indio_dev, chan);
566 
567 	meson_sar_adc_start_sample_engine(indio_dev);
568 	ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val);
569 	meson_sar_adc_stop_sample_engine(indio_dev);
570 
571 	meson_sar_adc_unlock(indio_dev);
572 
573 	if (ret) {
574 		dev_warn(dev, "failed to read sample for channel %lu: %d\n",
575 			 chan->address, ret);
576 		return ret;
577 	}
578 
579 	return IIO_VAL_INT;
580 }
581 
582 static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev,
583 					   const struct iio_chan_spec *chan,
584 					   int *val, int *val2, long mask)
585 {
586 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
587 	struct device *dev = indio_dev->dev.parent;
588 	int ret;
589 
590 	switch (mask) {
591 	case IIO_CHAN_INFO_RAW:
592 		return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING,
593 						ONE_SAMPLE, val);
594 
595 	case IIO_CHAN_INFO_AVERAGE_RAW:
596 		return meson_sar_adc_get_sample(indio_dev, chan,
597 						MEAN_AVERAGING, EIGHT_SAMPLES,
598 						val);
599 
600 	case IIO_CHAN_INFO_SCALE:
601 		if (chan->type == IIO_VOLTAGE) {
602 			ret = regulator_get_voltage(priv->vref);
603 			if (ret < 0) {
604 				dev_err(dev, "failed to get vref voltage: %d\n", ret);
605 				return ret;
606 			}
607 
608 			*val = ret / 1000;
609 			*val2 = priv->param->resolution;
610 			return IIO_VAL_FRACTIONAL_LOG2;
611 		} else if (chan->type == IIO_TEMP) {
612 			/* SoC specific multiplier and divider */
613 			*val = priv->param->temperature_multiplier;
614 			*val2 = priv->param->temperature_divider;
615 
616 			/* celsius to millicelsius */
617 			*val *= 1000;
618 
619 			return IIO_VAL_FRACTIONAL;
620 		} else {
621 			return -EINVAL;
622 		}
623 
624 	case IIO_CHAN_INFO_CALIBBIAS:
625 		*val = priv->calibbias;
626 		return IIO_VAL_INT;
627 
628 	case IIO_CHAN_INFO_CALIBSCALE:
629 		*val = priv->calibscale / MILLION;
630 		*val2 = priv->calibscale % MILLION;
631 		return IIO_VAL_INT_PLUS_MICRO;
632 
633 	case IIO_CHAN_INFO_OFFSET:
634 		*val = DIV_ROUND_CLOSEST(MESON_SAR_ADC_TEMP_OFFSET *
635 					 priv->param->temperature_divider,
636 					 priv->param->temperature_multiplier);
637 		*val -= priv->temperature_sensor_adc_val;
638 		return IIO_VAL_INT;
639 
640 	default:
641 		return -EINVAL;
642 	}
643 }
644 
645 static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
646 				  void __iomem *base)
647 {
648 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
649 	struct device *dev = indio_dev->dev.parent;
650 	struct clk_init_data init;
651 	const char *clk_parents[1];
652 
653 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_div", dev_name(dev));
654 	if (!init.name)
655 		return -ENOMEM;
656 
657 	init.flags = 0;
658 	init.ops = &clk_divider_ops;
659 	clk_parents[0] = __clk_get_name(priv->clkin);
660 	init.parent_names = clk_parents;
661 	init.num_parents = 1;
662 
663 	priv->clk_div.reg = base + MESON_SAR_ADC_REG3;
664 	priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT;
665 	priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH;
666 	priv->clk_div.hw.init = &init;
667 	priv->clk_div.flags = 0;
668 
669 	priv->adc_div_clk = devm_clk_register(dev, &priv->clk_div.hw);
670 	if (WARN_ON(IS_ERR(priv->adc_div_clk)))
671 		return PTR_ERR(priv->adc_div_clk);
672 
673 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_en", dev_name(dev));
674 	if (!init.name)
675 		return -ENOMEM;
676 
677 	init.flags = CLK_SET_RATE_PARENT;
678 	init.ops = &clk_gate_ops;
679 	clk_parents[0] = __clk_get_name(priv->adc_div_clk);
680 	init.parent_names = clk_parents;
681 	init.num_parents = 1;
682 
683 	priv->clk_gate.reg = base + MESON_SAR_ADC_REG3;
684 	priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN);
685 	priv->clk_gate.hw.init = &init;
686 
687 	priv->adc_clk = devm_clk_register(dev, &priv->clk_gate.hw);
688 	if (WARN_ON(IS_ERR(priv->adc_clk)))
689 		return PTR_ERR(priv->adc_clk);
690 
691 	return 0;
692 }
693 
694 static int meson_sar_adc_temp_sensor_init(struct iio_dev *indio_dev)
695 {
696 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
697 	u8 *buf, trimming_bits, trimming_mask, upper_adc_val;
698 	struct device *dev = indio_dev->dev.parent;
699 	struct nvmem_cell *temperature_calib;
700 	size_t read_len;
701 	int ret;
702 
703 	temperature_calib = devm_nvmem_cell_get(dev, "temperature_calib");
704 	if (IS_ERR(temperature_calib)) {
705 		ret = PTR_ERR(temperature_calib);
706 
707 		/*
708 		 * leave the temperature sensor disabled if no calibration data
709 		 * was passed via nvmem-cells.
710 		 */
711 		if (ret == -ENODEV)
712 			return 0;
713 
714 		return dev_err_probe(dev, ret, "failed to get temperature_calib cell\n");
715 	}
716 
717 	priv->tsc_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "amlogic,hhi-sysctrl");
718 	if (IS_ERR(priv->tsc_regmap))
719 		return dev_err_probe(dev, PTR_ERR(priv->tsc_regmap),
720 				     "failed to get amlogic,hhi-sysctrl regmap\n");
721 
722 	read_len = MESON_SAR_ADC_EFUSE_BYTES;
723 	buf = nvmem_cell_read(temperature_calib, &read_len);
724 	if (IS_ERR(buf))
725 		return dev_err_probe(dev, PTR_ERR(buf), "failed to read temperature_calib cell\n");
726 	if (read_len != MESON_SAR_ADC_EFUSE_BYTES) {
727 		kfree(buf);
728 		return dev_err_probe(dev, -EINVAL, "invalid read size of temperature_calib cell\n");
729 	}
730 
731 	trimming_bits = priv->param->temperature_trimming_bits;
732 	trimming_mask = BIT(trimming_bits) - 1;
733 
734 	priv->temperature_sensor_calibrated =
735 		buf[3] & MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED;
736 	priv->temperature_sensor_coefficient = buf[2] & trimming_mask;
737 
738 	upper_adc_val = FIELD_GET(MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL,
739 				  buf[3]);
740 
741 	priv->temperature_sensor_adc_val = buf[2];
742 	priv->temperature_sensor_adc_val |= upper_adc_val << BITS_PER_BYTE;
743 	priv->temperature_sensor_adc_val >>= trimming_bits;
744 
745 	kfree(buf);
746 
747 	return 0;
748 }
749 
750 static int meson_sar_adc_init(struct iio_dev *indio_dev)
751 {
752 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
753 	struct device *dev = indio_dev->dev.parent;
754 	int regval, i, ret;
755 
756 	/*
757 	 * make sure we start at CH7 input since the other muxes are only used
758 	 * for internal calibration.
759 	 */
760 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
761 
762 	if (priv->param->has_bl30_integration) {
763 		/*
764 		 * leave sampling delay and the input clocks as configured by
765 		 * BL30 to make sure BL30 gets the values it expects when
766 		 * reading the temperature sensor.
767 		 */
768 		regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
769 		if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED)
770 			return 0;
771 	}
772 
773 	meson_sar_adc_stop_sample_engine(indio_dev);
774 
775 	/*
776 	 * disable this bit as seems to be only relevant for Meson6 (based
777 	 * on the vendor driver), which we don't support at the moment.
778 	 */
779 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
780 			   MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 0);
781 
782 	/* disable all channels by default */
783 	regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
784 
785 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
786 			   MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0);
787 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
788 			   MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY,
789 			   MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
790 
791 	/* delay between two samples = (10+1) * 1uS */
792 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
793 			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
794 			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
795 				      10));
796 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
797 			   MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
798 			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
799 				      0));
800 
801 	/* delay between two samples = (10+1) * 1uS */
802 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
803 			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
804 			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
805 				      10));
806 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
807 			   MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
808 			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
809 				      1));
810 
811 	/*
812 	 * set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
813 	 * (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
814 	 */
815 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
816 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
817 			   MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
818 			   regval);
819 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
820 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
821 			   MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
822 			   regval);
823 
824 	/*
825 	 * set up the input channel muxes in MESON_SAR_ADC_AUX_SW
826 	 * (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
827 	 * MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
828 	 * MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
829 	 */
830 	regval = 0;
831 	for (i = 2; i <= 7; i++)
832 		regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
833 	regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
834 	regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
835 	regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
836 
837 	if (priv->temperature_sensor_calibrated) {
838 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
839 				   MESON_SAR_ADC_DELTA_10_TS_REVE1,
840 				   MESON_SAR_ADC_DELTA_10_TS_REVE1);
841 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
842 				   MESON_SAR_ADC_DELTA_10_TS_REVE0,
843 				   MESON_SAR_ADC_DELTA_10_TS_REVE0);
844 
845 		/*
846 		 * set bits [3:0] of the TSC (temperature sensor coefficient)
847 		 * to get the correct values when reading the temperature.
848 		 */
849 		regval = FIELD_PREP(MESON_SAR_ADC_DELTA_10_TS_C_MASK,
850 				    priv->temperature_sensor_coefficient);
851 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
852 				   MESON_SAR_ADC_DELTA_10_TS_C_MASK, regval);
853 
854 		if (priv->param->temperature_trimming_bits == 5) {
855 			if (priv->temperature_sensor_coefficient & BIT(4))
856 				regval = MESON_HHI_DPLL_TOP_0_TSC_BIT4;
857 			else
858 				regval = 0;
859 
860 			/*
861 			 * bit [4] (the 5th bit when starting to count at 1)
862 			 * of the TSC is located in the HHI register area.
863 			 */
864 			regmap_update_bits(priv->tsc_regmap,
865 					   MESON_HHI_DPLL_TOP_0,
866 					   MESON_HHI_DPLL_TOP_0_TSC_BIT4,
867 					   regval);
868 		}
869 	} else {
870 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
871 				   MESON_SAR_ADC_DELTA_10_TS_REVE1, 0);
872 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
873 				   MESON_SAR_ADC_DELTA_10_TS_REVE0, 0);
874 	}
875 
876 	ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
877 	if (ret)
878 		return dev_err_probe(dev, ret, "failed to set adc parent to clkin\n");
879 
880 	ret = clk_set_rate(priv->adc_clk, priv->param->clock_rate);
881 	if (ret)
882 		return dev_err_probe(dev, ret, "failed to set adc clock rate\n");
883 
884 	return 0;
885 }
886 
887 static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off)
888 {
889 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
890 	const struct meson_sar_adc_param *param = priv->param;
891 	u32 enable_mask;
892 
893 	if (param->bandgap_reg == MESON_SAR_ADC_REG11)
894 		enable_mask = MESON_SAR_ADC_REG11_BANDGAP_EN;
895 	else
896 		enable_mask = MESON_SAR_ADC_DELTA_10_TS_VBG_EN;
897 
898 	regmap_update_bits(priv->regmap, param->bandgap_reg, enable_mask,
899 			   on_off ? enable_mask : 0);
900 }
901 
902 static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
903 {
904 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
905 	struct device *dev = indio_dev->dev.parent;
906 	int ret;
907 	u32 regval;
908 
909 	ret = meson_sar_adc_lock(indio_dev);
910 	if (ret)
911 		goto err_lock;
912 
913 	ret = regulator_enable(priv->vref);
914 	if (ret < 0) {
915 		dev_err(dev, "failed to enable vref regulator\n");
916 		goto err_vref;
917 	}
918 
919 	ret = clk_prepare_enable(priv->core_clk);
920 	if (ret) {
921 		dev_err(dev, "failed to enable core clk\n");
922 		goto err_core_clk;
923 	}
924 
925 	regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
926 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
927 			   MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
928 
929 	meson_sar_adc_set_bandgap(indio_dev, true);
930 
931 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
932 			   MESON_SAR_ADC_REG3_ADC_EN,
933 			   MESON_SAR_ADC_REG3_ADC_EN);
934 
935 	udelay(5);
936 
937 	ret = clk_prepare_enable(priv->adc_clk);
938 	if (ret) {
939 		dev_err(dev, "failed to enable adc clk\n");
940 		goto err_adc_clk;
941 	}
942 
943 	meson_sar_adc_unlock(indio_dev);
944 
945 	return 0;
946 
947 err_adc_clk:
948 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
949 			   MESON_SAR_ADC_REG3_ADC_EN, 0);
950 	meson_sar_adc_set_bandgap(indio_dev, false);
951 	clk_disable_unprepare(priv->core_clk);
952 err_core_clk:
953 	regulator_disable(priv->vref);
954 err_vref:
955 	meson_sar_adc_unlock(indio_dev);
956 err_lock:
957 	return ret;
958 }
959 
960 static void meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
961 {
962 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
963 	int ret;
964 
965 	/*
966 	 * If taking the lock fails we have to assume that BL30 is broken. The
967 	 * best we can do then is to release the resources anyhow.
968 	 */
969 	ret = meson_sar_adc_lock(indio_dev);
970 	if (ret)
971 		dev_err(indio_dev->dev.parent, "Failed to lock ADC (%pE)\n", ERR_PTR(ret));
972 
973 	clk_disable_unprepare(priv->adc_clk);
974 
975 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
976 			   MESON_SAR_ADC_REG3_ADC_EN, 0);
977 
978 	meson_sar_adc_set_bandgap(indio_dev, false);
979 
980 	clk_disable_unprepare(priv->core_clk);
981 
982 	regulator_disable(priv->vref);
983 
984 	if (!ret)
985 		meson_sar_adc_unlock(indio_dev);
986 }
987 
988 static irqreturn_t meson_sar_adc_irq(int irq, void *data)
989 {
990 	struct iio_dev *indio_dev = data;
991 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
992 	unsigned int cnt, threshold;
993 	u32 regval;
994 
995 	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
996 	cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
997 	threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
998 
999 	if (cnt < threshold)
1000 		return IRQ_NONE;
1001 
1002 	complete(&priv->done);
1003 
1004 	return IRQ_HANDLED;
1005 }
1006 
1007 static int meson_sar_adc_calib(struct iio_dev *indio_dev)
1008 {
1009 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1010 	int ret, nominal0, nominal1, value0, value1;
1011 
1012 	/* use points 25% and 75% for calibration */
1013 	nominal0 = (1 << priv->param->resolution) / 4;
1014 	nominal1 = (1 << priv->param->resolution) * 3 / 4;
1015 
1016 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4);
1017 	usleep_range(10, 20);
1018 	ret = meson_sar_adc_get_sample(indio_dev,
1019 				       &indio_dev->channels[7],
1020 				       MEAN_AVERAGING, EIGHT_SAMPLES, &value0);
1021 	if (ret < 0)
1022 		goto out;
1023 
1024 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4);
1025 	usleep_range(10, 20);
1026 	ret = meson_sar_adc_get_sample(indio_dev,
1027 				       &indio_dev->channels[7],
1028 				       MEAN_AVERAGING, EIGHT_SAMPLES, &value1);
1029 	if (ret < 0)
1030 		goto out;
1031 
1032 	if (value1 <= value0) {
1033 		ret = -EINVAL;
1034 		goto out;
1035 	}
1036 
1037 	priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
1038 				   value1 - value0);
1039 	priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
1040 					     MILLION);
1041 	ret = 0;
1042 out:
1043 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
1044 
1045 	return ret;
1046 }
1047 
1048 static const struct iio_info meson_sar_adc_iio_info = {
1049 	.read_raw = meson_sar_adc_iio_info_read_raw,
1050 };
1051 
1052 static const struct meson_sar_adc_param meson_sar_adc_meson8_param = {
1053 	.has_bl30_integration = false,
1054 	.clock_rate = 1150000,
1055 	.bandgap_reg = MESON_SAR_ADC_DELTA_10,
1056 	.regmap_config = &meson_sar_adc_regmap_config_meson8,
1057 	.resolution = 10,
1058 	.temperature_trimming_bits = 4,
1059 	.temperature_multiplier = 18 * 10000,
1060 	.temperature_divider = 1024 * 10 * 85,
1061 };
1062 
1063 static const struct meson_sar_adc_param meson_sar_adc_meson8b_param = {
1064 	.has_bl30_integration = false,
1065 	.clock_rate = 1150000,
1066 	.bandgap_reg = MESON_SAR_ADC_DELTA_10,
1067 	.regmap_config = &meson_sar_adc_regmap_config_meson8,
1068 	.resolution = 10,
1069 	.temperature_trimming_bits = 5,
1070 	.temperature_multiplier = 10,
1071 	.temperature_divider = 32,
1072 };
1073 
1074 static const struct meson_sar_adc_param meson_sar_adc_gxbb_param = {
1075 	.has_bl30_integration = true,
1076 	.clock_rate = 1200000,
1077 	.bandgap_reg = MESON_SAR_ADC_REG11,
1078 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1079 	.resolution = 10,
1080 };
1081 
1082 static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
1083 	.has_bl30_integration = true,
1084 	.clock_rate = 1200000,
1085 	.bandgap_reg = MESON_SAR_ADC_REG11,
1086 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1087 	.resolution = 12,
1088 };
1089 
1090 static const struct meson_sar_adc_param meson_sar_adc_g12a_param = {
1091 	.has_bl30_integration = false,
1092 	.clock_rate = 1200000,
1093 	.bandgap_reg = MESON_SAR_ADC_REG11,
1094 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1095 	.resolution = 12,
1096 };
1097 
1098 static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
1099 	.param = &meson_sar_adc_meson8_param,
1100 	.name = "meson-meson8-saradc",
1101 };
1102 
1103 static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
1104 	.param = &meson_sar_adc_meson8b_param,
1105 	.name = "meson-meson8b-saradc",
1106 };
1107 
1108 static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
1109 	.param = &meson_sar_adc_meson8b_param,
1110 	.name = "meson-meson8m2-saradc",
1111 };
1112 
1113 static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
1114 	.param = &meson_sar_adc_gxbb_param,
1115 	.name = "meson-gxbb-saradc",
1116 };
1117 
1118 static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
1119 	.param = &meson_sar_adc_gxl_param,
1120 	.name = "meson-gxl-saradc",
1121 };
1122 
1123 static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
1124 	.param = &meson_sar_adc_gxl_param,
1125 	.name = "meson-gxm-saradc",
1126 };
1127 
1128 static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
1129 	.param = &meson_sar_adc_gxl_param,
1130 	.name = "meson-axg-saradc",
1131 };
1132 
1133 static const struct meson_sar_adc_data meson_sar_adc_g12a_data = {
1134 	.param = &meson_sar_adc_g12a_param,
1135 	.name = "meson-g12a-saradc",
1136 };
1137 
1138 static const struct of_device_id meson_sar_adc_of_match[] = {
1139 	{
1140 		.compatible = "amlogic,meson8-saradc",
1141 		.data = &meson_sar_adc_meson8_data,
1142 	}, {
1143 		.compatible = "amlogic,meson8b-saradc",
1144 		.data = &meson_sar_adc_meson8b_data,
1145 	}, {
1146 		.compatible = "amlogic,meson8m2-saradc",
1147 		.data = &meson_sar_adc_meson8m2_data,
1148 	}, {
1149 		.compatible = "amlogic,meson-gxbb-saradc",
1150 		.data = &meson_sar_adc_gxbb_data,
1151 	}, {
1152 		.compatible = "amlogic,meson-gxl-saradc",
1153 		.data = &meson_sar_adc_gxl_data,
1154 	}, {
1155 		.compatible = "amlogic,meson-gxm-saradc",
1156 		.data = &meson_sar_adc_gxm_data,
1157 	}, {
1158 		.compatible = "amlogic,meson-axg-saradc",
1159 		.data = &meson_sar_adc_axg_data,
1160 	}, {
1161 		.compatible = "amlogic,meson-g12a-saradc",
1162 		.data = &meson_sar_adc_g12a_data,
1163 	},
1164 	{ /* sentinel */ }
1165 };
1166 MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match);
1167 
1168 static int meson_sar_adc_probe(struct platform_device *pdev)
1169 {
1170 	const struct meson_sar_adc_data *match_data;
1171 	struct meson_sar_adc_priv *priv;
1172 	struct device *dev = &pdev->dev;
1173 	struct iio_dev *indio_dev;
1174 	void __iomem *base;
1175 	int irq, ret;
1176 
1177 	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
1178 	if (!indio_dev)
1179 		return dev_err_probe(dev, -ENOMEM, "failed allocating iio device\n");
1180 
1181 	priv = iio_priv(indio_dev);
1182 	init_completion(&priv->done);
1183 
1184 	match_data = of_device_get_match_data(dev);
1185 	if (!match_data)
1186 		return dev_err_probe(dev, -ENODEV, "failed to get match data\n");
1187 
1188 	priv->param = match_data->param;
1189 
1190 	indio_dev->name = match_data->name;
1191 	indio_dev->modes = INDIO_DIRECT_MODE;
1192 	indio_dev->info = &meson_sar_adc_iio_info;
1193 
1194 	base = devm_platform_ioremap_resource(pdev, 0);
1195 	if (IS_ERR(base))
1196 		return PTR_ERR(base);
1197 
1198 	priv->regmap = devm_regmap_init_mmio(dev, base, priv->param->regmap_config);
1199 	if (IS_ERR(priv->regmap))
1200 		return PTR_ERR(priv->regmap);
1201 
1202 	irq = irq_of_parse_and_map(dev->of_node, 0);
1203 	if (!irq)
1204 		return -EINVAL;
1205 
1206 	ret = devm_request_irq(dev, irq, meson_sar_adc_irq, IRQF_SHARED, dev_name(dev), indio_dev);
1207 	if (ret)
1208 		return ret;
1209 
1210 	priv->clkin = devm_clk_get(dev, "clkin");
1211 	if (IS_ERR(priv->clkin))
1212 		return dev_err_probe(dev, PTR_ERR(priv->clkin), "failed to get clkin\n");
1213 
1214 	priv->core_clk = devm_clk_get(dev, "core");
1215 	if (IS_ERR(priv->core_clk))
1216 		return dev_err_probe(dev, PTR_ERR(priv->core_clk), "failed to get core clk\n");
1217 
1218 	priv->adc_clk = devm_clk_get_optional(dev, "adc_clk");
1219 	if (IS_ERR(priv->adc_clk))
1220 		return dev_err_probe(dev, PTR_ERR(priv->adc_clk), "failed to get adc clk\n");
1221 
1222 	priv->adc_sel_clk = devm_clk_get_optional(dev, "adc_sel");
1223 	if (IS_ERR(priv->adc_sel_clk))
1224 		return dev_err_probe(dev, PTR_ERR(priv->adc_sel_clk), "failed to get adc_sel clk\n");
1225 
1226 	/* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */
1227 	if (!priv->adc_clk) {
1228 		ret = meson_sar_adc_clk_init(indio_dev, base);
1229 		if (ret)
1230 			return ret;
1231 	}
1232 
1233 	priv->vref = devm_regulator_get(dev, "vref");
1234 	if (IS_ERR(priv->vref))
1235 		return dev_err_probe(dev, PTR_ERR(priv->vref), "failed to get vref regulator\n");
1236 
1237 	priv->calibscale = MILLION;
1238 
1239 	if (priv->param->temperature_trimming_bits) {
1240 		ret = meson_sar_adc_temp_sensor_init(indio_dev);
1241 		if (ret)
1242 			return ret;
1243 	}
1244 
1245 	if (priv->temperature_sensor_calibrated) {
1246 		indio_dev->channels = meson_sar_adc_and_temp_iio_channels;
1247 		indio_dev->num_channels =
1248 			ARRAY_SIZE(meson_sar_adc_and_temp_iio_channels);
1249 	} else {
1250 		indio_dev->channels = meson_sar_adc_iio_channels;
1251 		indio_dev->num_channels =
1252 			ARRAY_SIZE(meson_sar_adc_iio_channels);
1253 	}
1254 
1255 	ret = meson_sar_adc_init(indio_dev);
1256 	if (ret)
1257 		goto err;
1258 
1259 	mutex_init(&priv->lock);
1260 
1261 	ret = meson_sar_adc_hw_enable(indio_dev);
1262 	if (ret)
1263 		goto err;
1264 
1265 	ret = meson_sar_adc_calib(indio_dev);
1266 	if (ret)
1267 		dev_warn(dev, "calibration failed\n");
1268 
1269 	platform_set_drvdata(pdev, indio_dev);
1270 
1271 	ret = iio_device_register(indio_dev);
1272 	if (ret)
1273 		goto err_hw;
1274 
1275 	return 0;
1276 
1277 err_hw:
1278 	meson_sar_adc_hw_disable(indio_dev);
1279 err:
1280 	return ret;
1281 }
1282 
1283 static int meson_sar_adc_remove(struct platform_device *pdev)
1284 {
1285 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
1286 
1287 	iio_device_unregister(indio_dev);
1288 
1289 	meson_sar_adc_hw_disable(indio_dev);
1290 
1291 	return 0;
1292 }
1293 
1294 static int meson_sar_adc_suspend(struct device *dev)
1295 {
1296 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1297 
1298 	meson_sar_adc_hw_disable(indio_dev);
1299 
1300 	return 0;
1301 }
1302 
1303 static int meson_sar_adc_resume(struct device *dev)
1304 {
1305 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1306 
1307 	return meson_sar_adc_hw_enable(indio_dev);
1308 }
1309 
1310 static DEFINE_SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops,
1311 				meson_sar_adc_suspend, meson_sar_adc_resume);
1312 
1313 static struct platform_driver meson_sar_adc_driver = {
1314 	.probe		= meson_sar_adc_probe,
1315 	.remove		= meson_sar_adc_remove,
1316 	.driver		= {
1317 		.name	= "meson-saradc",
1318 		.of_match_table = meson_sar_adc_of_match,
1319 		.pm = pm_sleep_ptr(&meson_sar_adc_pm_ops),
1320 	},
1321 };
1322 
1323 module_platform_driver(meson_sar_adc_driver);
1324 
1325 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
1326 MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver");
1327 MODULE_LICENSE("GPL v2");
1328