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 <[email protected]>
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/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		6
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 	#define MESON_SAR_ADC_REG11_CMV_SEL			BIT(6)
159 	#define MESON_SAR_ADC_REG11_VREF_VOLTAGE		BIT(5)
160 	#define MESON_SAR_ADC_REG11_EOC				BIT(1)
161 	#define MESON_SAR_ADC_REG11_VREF_SEL			BIT(0)
162 
163 #define MESON_SAR_ADC_REG13					0x34
164 	#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK	GENMASK(13, 8)
165 
166 #define MESON_SAR_ADC_MAX_FIFO_SIZE				32
167 #define MESON_SAR_ADC_TIMEOUT					100 /* ms */
168 #define MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL			6
169 #define MESON_SAR_ADC_VOLTAGE_AND_MUX_CHANNEL			7
170 #define MESON_SAR_ADC_TEMP_OFFSET				27
171 
172 /* temperature sensor calibration information in eFuse */
173 #define MESON_SAR_ADC_EFUSE_BYTES				4
174 #define MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL			GENMASK(6, 0)
175 #define MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED			BIT(7)
176 
177 #define MESON_HHI_DPLL_TOP_0					0x318
178 #define MESON_HHI_DPLL_TOP_0_TSC_BIT4				BIT(9)
179 
180 /* for use with IIO_VAL_INT_PLUS_MICRO */
181 #define MILLION							1000000
182 
183 #define MESON_SAR_ADC_CHAN(_chan) {					\
184 	.type = IIO_VOLTAGE,						\
185 	.indexed = 1,							\
186 	.channel = _chan,						\
187 	.address = _chan,						\
188 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
189 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
190 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
191 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
192 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
193 	.datasheet_name = "SAR_ADC_CH"#_chan,				\
194 }
195 
196 #define MESON_SAR_ADC_TEMP_CHAN(_chan) {				\
197 	.type = IIO_TEMP,						\
198 	.channel = _chan,						\
199 	.address = MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL,		\
200 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
201 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
202 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |		\
203 					BIT(IIO_CHAN_INFO_SCALE),	\
204 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
205 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
206 	.datasheet_name = "TEMP_SENSOR",				\
207 }
208 
209 #define MESON_SAR_ADC_MUX(_chan, _sel) {				\
210 	.type = IIO_VOLTAGE,						\
211 	.channel = _chan,						\
212 	.indexed = 1,							\
213 	.address = MESON_SAR_ADC_VOLTAGE_AND_MUX_CHANNEL,		\
214 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
215 				BIT(IIO_CHAN_INFO_AVERAGE_RAW),		\
216 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
217 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) |	\
218 				BIT(IIO_CHAN_INFO_CALIBSCALE),		\
219 	.datasheet_name = "SAR_ADC_MUX_"#_sel,				\
220 }
221 
222 enum meson_sar_adc_vref_sel {
223 	VREF_CALIBATION_VOLTAGE = 0,
224 	VREF_VDDA = 1,
225 };
226 
227 enum meson_sar_adc_avg_mode {
228 	NO_AVERAGING = 0x0,
229 	MEAN_AVERAGING = 0x1,
230 	MEDIAN_AVERAGING = 0x2,
231 };
232 
233 enum meson_sar_adc_num_samples {
234 	ONE_SAMPLE = 0x0,
235 	TWO_SAMPLES = 0x1,
236 	FOUR_SAMPLES = 0x2,
237 	EIGHT_SAMPLES = 0x3,
238 };
239 
240 enum meson_sar_adc_chan7_mux_sel {
241 	CHAN7_MUX_VSS = 0x0,
242 	CHAN7_MUX_VDD_DIV4 = 0x1,
243 	CHAN7_MUX_VDD_DIV2 = 0x2,
244 	CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
245 	CHAN7_MUX_VDD = 0x4,
246 	CHAN7_MUX_CH7_INPUT = 0x7,
247 };
248 
249 enum meson_sar_adc_channel_index {
250 	NUM_CHAN_0,
251 	NUM_CHAN_1,
252 	NUM_CHAN_2,
253 	NUM_CHAN_3,
254 	NUM_CHAN_4,
255 	NUM_CHAN_5,
256 	NUM_CHAN_6,
257 	NUM_CHAN_7,
258 	NUM_CHAN_TEMP,
259 	NUM_MUX_0_VSS,
260 	NUM_MUX_1_VDD_DIV4,
261 	NUM_MUX_2_VDD_DIV2,
262 	NUM_MUX_3_VDD_MUL3_DIV4,
263 	NUM_MUX_4_VDD,
264 };
265 
266 static enum meson_sar_adc_chan7_mux_sel chan7_mux_values[] = {
267 	CHAN7_MUX_VSS,
268 	CHAN7_MUX_VDD_DIV4,
269 	CHAN7_MUX_VDD_DIV2,
270 	CHAN7_MUX_VDD_MUL3_DIV4,
271 	CHAN7_MUX_VDD,
272 };
273 
274 static const char * const chan7_mux_names[] = {
275 	[CHAN7_MUX_VSS] = "gnd",
276 	[CHAN7_MUX_VDD_DIV4] = "0.25vdd",
277 	[CHAN7_MUX_VDD_DIV2] = "0.5vdd",
278 	[CHAN7_MUX_VDD_MUL3_DIV4] = "0.75vdd",
279 	[CHAN7_MUX_VDD] = "vdd",
280 };
281 
282 static const struct iio_chan_spec meson_sar_adc_iio_channels[] = {
283 	MESON_SAR_ADC_CHAN(NUM_CHAN_0),
284 	MESON_SAR_ADC_CHAN(NUM_CHAN_1),
285 	MESON_SAR_ADC_CHAN(NUM_CHAN_2),
286 	MESON_SAR_ADC_CHAN(NUM_CHAN_3),
287 	MESON_SAR_ADC_CHAN(NUM_CHAN_4),
288 	MESON_SAR_ADC_CHAN(NUM_CHAN_5),
289 	MESON_SAR_ADC_CHAN(NUM_CHAN_6),
290 	MESON_SAR_ADC_CHAN(NUM_CHAN_7),
291 	MESON_SAR_ADC_MUX(NUM_MUX_0_VSS, 0),
292 	MESON_SAR_ADC_MUX(NUM_MUX_1_VDD_DIV4, 1),
293 	MESON_SAR_ADC_MUX(NUM_MUX_2_VDD_DIV2, 2),
294 	MESON_SAR_ADC_MUX(NUM_MUX_3_VDD_MUL3_DIV4, 3),
295 	MESON_SAR_ADC_MUX(NUM_MUX_4_VDD, 4),
296 };
297 
298 static const struct iio_chan_spec meson_sar_adc_and_temp_iio_channels[] = {
299 	MESON_SAR_ADC_CHAN(NUM_CHAN_0),
300 	MESON_SAR_ADC_CHAN(NUM_CHAN_1),
301 	MESON_SAR_ADC_CHAN(NUM_CHAN_2),
302 	MESON_SAR_ADC_CHAN(NUM_CHAN_3),
303 	MESON_SAR_ADC_CHAN(NUM_CHAN_4),
304 	MESON_SAR_ADC_CHAN(NUM_CHAN_5),
305 	MESON_SAR_ADC_CHAN(NUM_CHAN_6),
306 	MESON_SAR_ADC_CHAN(NUM_CHAN_7),
307 	MESON_SAR_ADC_TEMP_CHAN(NUM_CHAN_TEMP),
308 	MESON_SAR_ADC_MUX(NUM_MUX_0_VSS, 0),
309 	MESON_SAR_ADC_MUX(NUM_MUX_1_VDD_DIV4, 1),
310 	MESON_SAR_ADC_MUX(NUM_MUX_2_VDD_DIV2, 2),
311 	MESON_SAR_ADC_MUX(NUM_MUX_3_VDD_MUL3_DIV4, 3),
312 	MESON_SAR_ADC_MUX(NUM_MUX_4_VDD, 4),
313 };
314 
315 struct meson_sar_adc_param {
316 	bool					has_bl30_integration;
317 	unsigned long				clock_rate;
318 	unsigned int				resolution;
319 	const struct regmap_config		*regmap_config;
320 	u8					temperature_trimming_bits;
321 	unsigned int				temperature_multiplier;
322 	unsigned int				temperature_divider;
323 	u8					disable_ring_counter;
324 	bool					has_vref_select;
325 	u8					vref_select;
326 	u8					cmv_select;
327 	u8					adc_eoc;
328 	enum meson_sar_adc_vref_sel		vref_voltage;
329 };
330 
331 struct meson_sar_adc_data {
332 	const struct meson_sar_adc_param	*param;
333 	const char				*name;
334 };
335 
336 struct meson_sar_adc_priv {
337 	struct regmap				*regmap;
338 	struct regulator			*vref;
339 	const struct meson_sar_adc_param	*param;
340 	struct clk				*clkin;
341 	struct clk				*core_clk;
342 	struct clk				*adc_sel_clk;
343 	struct clk				*adc_clk;
344 	struct clk_gate				clk_gate;
345 	struct clk				*adc_div_clk;
346 	struct clk_divider			clk_div;
347 	struct completion			done;
348 	/* lock to protect against multiple access to the device */
349 	struct mutex				lock;
350 	int					calibbias;
351 	int					calibscale;
352 	struct regmap				*tsc_regmap;
353 	bool					temperature_sensor_calibrated;
354 	u8					temperature_sensor_coefficient;
355 	u16					temperature_sensor_adc_val;
356 	enum meson_sar_adc_chan7_mux_sel	chan7_mux_sel;
357 };
358 
359 static const struct regmap_config meson_sar_adc_regmap_config_gxbb = {
360 	.reg_bits = 8,
361 	.val_bits = 32,
362 	.reg_stride = 4,
363 	.max_register = MESON_SAR_ADC_REG13,
364 };
365 
366 static const struct regmap_config meson_sar_adc_regmap_config_meson8 = {
367 	.reg_bits = 8,
368 	.val_bits = 32,
369 	.reg_stride = 4,
370 	.max_register = MESON_SAR_ADC_DELTA_10,
371 };
372 
373 static const struct iio_chan_spec *
find_channel_by_num(struct iio_dev * indio_dev,int num)374 find_channel_by_num(struct iio_dev *indio_dev, int num)
375 {
376 	int i;
377 
378 	for (i = 0; i < indio_dev->num_channels; i++)
379 		if (indio_dev->channels[i].channel == num)
380 			return &indio_dev->channels[i];
381 	return NULL;
382 }
383 
meson_sar_adc_get_fifo_count(struct iio_dev * indio_dev)384 static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev)
385 {
386 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
387 	u32 regval;
388 
389 	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
390 
391 	return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
392 }
393 
meson_sar_adc_calib_val(struct iio_dev * indio_dev,int val)394 static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val)
395 {
396 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
397 	int tmp;
398 
399 	/* use val_calib = scale * val_raw + offset calibration function */
400 	tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
401 
402 	return clamp(tmp, 0, (1 << priv->param->resolution) - 1);
403 }
404 
meson_sar_adc_wait_busy_clear(struct iio_dev * indio_dev)405 static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev)
406 {
407 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
408 	int val;
409 
410 	/*
411 	 * NOTE: we need a small delay before reading the status, otherwise
412 	 * the sample engine may not have started internally (which would
413 	 * seem to us that sampling is already finished).
414 	 */
415 	udelay(1);
416 	return regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_REG0, val,
417 					       !FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, val),
418 					       1, 10000);
419 }
420 
meson_sar_adc_set_chan7_mux(struct iio_dev * indio_dev,enum meson_sar_adc_chan7_mux_sel sel)421 static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev,
422 					enum meson_sar_adc_chan7_mux_sel sel)
423 {
424 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
425 	u32 regval;
426 
427 	regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
428 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
429 			   MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
430 
431 	usleep_range(10, 20);
432 
433 	priv->chan7_mux_sel = sel;
434 }
435 
meson_sar_adc_read_raw_sample(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,int * val)436 static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
437 					 const struct iio_chan_spec *chan,
438 					 int *val)
439 {
440 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
441 	struct device *dev = indio_dev->dev.parent;
442 	int regval, fifo_chan, fifo_val, count;
443 
444 	if (!wait_for_completion_timeout(&priv->done,
445 				msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
446 		return -ETIMEDOUT;
447 
448 	count = meson_sar_adc_get_fifo_count(indio_dev);
449 	if (count != 1) {
450 		dev_err(dev, "ADC FIFO has %d element(s) instead of one\n", count);
451 		return -EINVAL;
452 	}
453 
454 	regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
455 	fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
456 	if (fifo_chan != chan->address) {
457 		dev_err(dev, "ADC FIFO entry belongs to channel %d instead of %lu\n",
458 			fifo_chan, chan->address);
459 		return -EINVAL;
460 	}
461 
462 	fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
463 	fifo_val &= GENMASK(priv->param->resolution - 1, 0);
464 	*val = meson_sar_adc_calib_val(indio_dev, fifo_val);
465 
466 	return 0;
467 }
468 
meson_sar_adc_set_averaging(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum meson_sar_adc_avg_mode mode,enum meson_sar_adc_num_samples samples)469 static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev,
470 					const struct iio_chan_spec *chan,
471 					enum meson_sar_adc_avg_mode mode,
472 					enum meson_sar_adc_num_samples samples)
473 {
474 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
475 	int val, address = chan->address;
476 
477 	val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(address);
478 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
479 			   MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(address),
480 			   val);
481 
482 	val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(address);
483 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
484 			   MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(address), val);
485 }
486 
meson_sar_adc_enable_channel(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)487 static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev,
488 					const struct iio_chan_spec *chan)
489 {
490 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
491 	u32 regval;
492 
493 	/*
494 	 * the SAR ADC engine allows sampling multiple channels at the same
495 	 * time. to keep it simple we're only working with one *internal*
496 	 * channel, which starts counting at index 0 (which means: count = 1).
497 	 */
498 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
499 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
500 			   MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
501 
502 	/* map channel index 0 to the channel which we want to read */
503 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0),
504 			    chan->address);
505 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
506 			   MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
507 
508 	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
509 			    chan->address);
510 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
511 			   MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
512 			   regval);
513 
514 	regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
515 			    chan->address);
516 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
517 			   MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
518 			   regval);
519 
520 	if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL) {
521 		if (chan->type == IIO_TEMP)
522 			regval = MESON_SAR_ADC_DELTA_10_TEMP_SEL;
523 		else
524 			regval = 0;
525 
526 		regmap_update_bits(priv->regmap,
527 				   MESON_SAR_ADC_DELTA_10,
528 				   MESON_SAR_ADC_DELTA_10_TEMP_SEL, regval);
529 	} else if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_MUX_CHANNEL) {
530 		enum meson_sar_adc_chan7_mux_sel sel;
531 
532 		if (chan->channel == NUM_CHAN_7)
533 			sel = CHAN7_MUX_CH7_INPUT;
534 		else
535 			sel = chan7_mux_values[chan->channel - NUM_MUX_0_VSS];
536 		if (sel != priv->chan7_mux_sel)
537 			meson_sar_adc_set_chan7_mux(indio_dev, sel);
538 	}
539 }
540 
meson_sar_adc_start_sample_engine(struct iio_dev * indio_dev)541 static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
542 {
543 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
544 
545 	reinit_completion(&priv->done);
546 
547 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_REG0,
548 			MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
549 
550 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_REG0,
551 			MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
552 
553 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_REG0,
554 			MESON_SAR_ADC_REG0_SAMPLING_START);
555 }
556 
meson_sar_adc_stop_sample_engine(struct iio_dev * indio_dev)557 static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
558 {
559 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
560 
561 	regmap_clear_bits(priv->regmap, MESON_SAR_ADC_REG0,
562 			  MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
563 
564 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_REG0,
565 			MESON_SAR_ADC_REG0_SAMPLING_STOP);
566 
567 	/* wait until all modules are stopped */
568 	meson_sar_adc_wait_busy_clear(indio_dev);
569 
570 	regmap_clear_bits(priv->regmap, MESON_SAR_ADC_REG0,
571 			  MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
572 }
573 
meson_sar_adc_lock(struct iio_dev * indio_dev)574 static int meson_sar_adc_lock(struct iio_dev *indio_dev)
575 {
576 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
577 	int val, ret;
578 
579 	mutex_lock(&priv->lock);
580 
581 	if (priv->param->has_bl30_integration) {
582 		/* prevent BL30 from using the SAR ADC while we are using it */
583 		regmap_set_bits(priv->regmap, MESON_SAR_ADC_DELAY,
584 				MESON_SAR_ADC_DELAY_KERNEL_BUSY);
585 
586 		udelay(1);
587 
588 		/*
589 		 * wait until BL30 releases it's lock (so we can use the SAR
590 		 * ADC)
591 		 */
592 		ret = regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_DELAY, val,
593 						      !(val & MESON_SAR_ADC_DELAY_BL30_BUSY),
594 						      1, 10000);
595 		if (ret) {
596 			mutex_unlock(&priv->lock);
597 			return ret;
598 		}
599 	}
600 
601 	return 0;
602 }
603 
meson_sar_adc_unlock(struct iio_dev * indio_dev)604 static void meson_sar_adc_unlock(struct iio_dev *indio_dev)
605 {
606 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
607 
608 	if (priv->param->has_bl30_integration)
609 		/* allow BL30 to use the SAR ADC again */
610 		regmap_clear_bits(priv->regmap, MESON_SAR_ADC_DELAY,
611 				  MESON_SAR_ADC_DELAY_KERNEL_BUSY);
612 
613 	mutex_unlock(&priv->lock);
614 }
615 
meson_sar_adc_clear_fifo(struct iio_dev * indio_dev)616 static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev)
617 {
618 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
619 	unsigned int count, tmp;
620 
621 	for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
622 		if (!meson_sar_adc_get_fifo_count(indio_dev))
623 			break;
624 
625 		regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
626 	}
627 }
628 
meson_sar_adc_get_sample(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum meson_sar_adc_avg_mode avg_mode,enum meson_sar_adc_num_samples avg_samples,int * val)629 static int meson_sar_adc_get_sample(struct iio_dev *indio_dev,
630 				    const struct iio_chan_spec *chan,
631 				    enum meson_sar_adc_avg_mode avg_mode,
632 				    enum meson_sar_adc_num_samples avg_samples,
633 				    int *val)
634 {
635 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
636 	struct device *dev = indio_dev->dev.parent;
637 	int ret;
638 
639 	if (chan->type == IIO_TEMP && !priv->temperature_sensor_calibrated)
640 		return -ENOTSUPP;
641 
642 	ret = meson_sar_adc_lock(indio_dev);
643 	if (ret)
644 		return ret;
645 
646 	/* clear the FIFO to make sure we're not reading old values */
647 	meson_sar_adc_clear_fifo(indio_dev);
648 
649 	meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples);
650 
651 	meson_sar_adc_enable_channel(indio_dev, chan);
652 
653 	meson_sar_adc_start_sample_engine(indio_dev);
654 	ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val);
655 	meson_sar_adc_stop_sample_engine(indio_dev);
656 
657 	meson_sar_adc_unlock(indio_dev);
658 
659 	if (ret) {
660 		dev_warn(dev, "failed to read sample for channel %lu: %d\n",
661 			 chan->address, ret);
662 		return ret;
663 	}
664 
665 	return IIO_VAL_INT;
666 }
667 
meson_sar_adc_iio_info_read_raw(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,int * val,int * val2,long mask)668 static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev,
669 					   const struct iio_chan_spec *chan,
670 					   int *val, int *val2, long mask)
671 {
672 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
673 	struct device *dev = indio_dev->dev.parent;
674 	int ret;
675 
676 	switch (mask) {
677 	case IIO_CHAN_INFO_RAW:
678 		return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING,
679 						ONE_SAMPLE, val);
680 
681 	case IIO_CHAN_INFO_AVERAGE_RAW:
682 		return meson_sar_adc_get_sample(indio_dev, chan,
683 						MEAN_AVERAGING, EIGHT_SAMPLES,
684 						val);
685 
686 	case IIO_CHAN_INFO_SCALE:
687 		if (chan->type == IIO_VOLTAGE) {
688 			ret = regulator_get_voltage(priv->vref);
689 			if (ret < 0) {
690 				dev_err(dev, "failed to get vref voltage: %d\n", ret);
691 				return ret;
692 			}
693 
694 			*val = ret / 1000;
695 			*val2 = priv->param->resolution;
696 			return IIO_VAL_FRACTIONAL_LOG2;
697 		} else if (chan->type == IIO_TEMP) {
698 			/* SoC specific multiplier and divider */
699 			*val = priv->param->temperature_multiplier;
700 			*val2 = priv->param->temperature_divider;
701 
702 			/* celsius to millicelsius */
703 			*val *= 1000;
704 
705 			return IIO_VAL_FRACTIONAL;
706 		} else {
707 			return -EINVAL;
708 		}
709 
710 	case IIO_CHAN_INFO_CALIBBIAS:
711 		*val = priv->calibbias;
712 		return IIO_VAL_INT;
713 
714 	case IIO_CHAN_INFO_CALIBSCALE:
715 		*val = priv->calibscale / MILLION;
716 		*val2 = priv->calibscale % MILLION;
717 		return IIO_VAL_INT_PLUS_MICRO;
718 
719 	case IIO_CHAN_INFO_OFFSET:
720 		*val = DIV_ROUND_CLOSEST(MESON_SAR_ADC_TEMP_OFFSET *
721 					 priv->param->temperature_divider,
722 					 priv->param->temperature_multiplier);
723 		*val -= priv->temperature_sensor_adc_val;
724 		return IIO_VAL_INT;
725 
726 	default:
727 		return -EINVAL;
728 	}
729 }
730 
meson_sar_adc_clk_init(struct iio_dev * indio_dev,void __iomem * base)731 static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
732 				  void __iomem *base)
733 {
734 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
735 	struct device *dev = indio_dev->dev.parent;
736 	struct clk_init_data init;
737 	const char *clk_parents[1];
738 
739 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_div", dev_name(dev));
740 	if (!init.name)
741 		return -ENOMEM;
742 
743 	init.flags = 0;
744 	init.ops = &clk_divider_ops;
745 	clk_parents[0] = __clk_get_name(priv->clkin);
746 	init.parent_names = clk_parents;
747 	init.num_parents = 1;
748 
749 	priv->clk_div.reg = base + MESON_SAR_ADC_REG3;
750 	priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT;
751 	priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH;
752 	priv->clk_div.hw.init = &init;
753 	priv->clk_div.flags = 0;
754 
755 	priv->adc_div_clk = devm_clk_register(dev, &priv->clk_div.hw);
756 	if (WARN_ON(IS_ERR(priv->adc_div_clk)))
757 		return PTR_ERR(priv->adc_div_clk);
758 
759 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_en", dev_name(dev));
760 	if (!init.name)
761 		return -ENOMEM;
762 
763 	init.flags = CLK_SET_RATE_PARENT;
764 	init.ops = &clk_gate_ops;
765 	clk_parents[0] = __clk_get_name(priv->adc_div_clk);
766 	init.parent_names = clk_parents;
767 	init.num_parents = 1;
768 
769 	priv->clk_gate.reg = base + MESON_SAR_ADC_REG3;
770 	priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN);
771 	priv->clk_gate.hw.init = &init;
772 
773 	priv->adc_clk = devm_clk_register(dev, &priv->clk_gate.hw);
774 	if (WARN_ON(IS_ERR(priv->adc_clk)))
775 		return PTR_ERR(priv->adc_clk);
776 
777 	return 0;
778 }
779 
meson_sar_adc_temp_sensor_init(struct iio_dev * indio_dev)780 static int meson_sar_adc_temp_sensor_init(struct iio_dev *indio_dev)
781 {
782 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
783 	u8 *buf, trimming_bits, trimming_mask, upper_adc_val;
784 	struct device *dev = indio_dev->dev.parent;
785 	struct nvmem_cell *temperature_calib;
786 	size_t read_len;
787 	int ret;
788 
789 	temperature_calib = devm_nvmem_cell_get(dev, "temperature_calib");
790 	if (IS_ERR(temperature_calib)) {
791 		ret = PTR_ERR(temperature_calib);
792 
793 		/*
794 		 * leave the temperature sensor disabled if no calibration data
795 		 * was passed via nvmem-cells.
796 		 */
797 		if (ret == -ENODEV)
798 			return 0;
799 
800 		return dev_err_probe(dev, ret, "failed to get temperature_calib cell\n");
801 	}
802 
803 	priv->tsc_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "amlogic,hhi-sysctrl");
804 	if (IS_ERR(priv->tsc_regmap))
805 		return dev_err_probe(dev, PTR_ERR(priv->tsc_regmap),
806 				     "failed to get amlogic,hhi-sysctrl regmap\n");
807 
808 	read_len = MESON_SAR_ADC_EFUSE_BYTES;
809 	buf = nvmem_cell_read(temperature_calib, &read_len);
810 	if (IS_ERR(buf))
811 		return dev_err_probe(dev, PTR_ERR(buf), "failed to read temperature_calib cell\n");
812 	if (read_len != MESON_SAR_ADC_EFUSE_BYTES) {
813 		kfree(buf);
814 		return dev_err_probe(dev, -EINVAL, "invalid read size of temperature_calib cell\n");
815 	}
816 
817 	trimming_bits = priv->param->temperature_trimming_bits;
818 	trimming_mask = BIT(trimming_bits) - 1;
819 
820 	priv->temperature_sensor_calibrated =
821 		buf[3] & MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED;
822 	priv->temperature_sensor_coefficient = buf[2] & trimming_mask;
823 
824 	upper_adc_val = FIELD_GET(MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL,
825 				  buf[3]);
826 
827 	priv->temperature_sensor_adc_val = buf[2];
828 	priv->temperature_sensor_adc_val |= upper_adc_val << BITS_PER_BYTE;
829 	priv->temperature_sensor_adc_val >>= trimming_bits;
830 
831 	kfree(buf);
832 
833 	return 0;
834 }
835 
meson_sar_adc_init(struct iio_dev * indio_dev)836 static int meson_sar_adc_init(struct iio_dev *indio_dev)
837 {
838 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
839 	struct device *dev = indio_dev->dev.parent;
840 	int regval, i, ret;
841 
842 	/*
843 	 * make sure we start at CH7 input since the other muxes are only used
844 	 * for internal calibration.
845 	 */
846 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
847 
848 	if (priv->param->has_bl30_integration) {
849 		/*
850 		 * leave sampling delay and the input clocks as configured by
851 		 * BL30 to make sure BL30 gets the values it expects when
852 		 * reading the temperature sensor.
853 		 */
854 		regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
855 		if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED)
856 			return 0;
857 	}
858 
859 	meson_sar_adc_stop_sample_engine(indio_dev);
860 
861 	/*
862 	 * disable this bit as seems to be only relevant for Meson6 (based
863 	 * on the vendor driver), which we don't support at the moment.
864 	 */
865 	regmap_clear_bits(priv->regmap, MESON_SAR_ADC_REG0,
866 			  MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL);
867 
868 	/* disable all channels by default */
869 	regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
870 
871 	regmap_clear_bits(priv->regmap, MESON_SAR_ADC_REG3,
872 			  MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE);
873 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_REG3,
874 			MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
875 
876 	/* delay between two samples = (10+1) * 1uS */
877 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
878 			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
879 			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
880 				      10));
881 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
882 			   MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
883 			   FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
884 				      0));
885 
886 	/* delay between two samples = (10+1) * 1uS */
887 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
888 			   MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
889 			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
890 				      10));
891 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
892 			   MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
893 			   FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
894 				      1));
895 
896 	/*
897 	 * set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
898 	 * (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
899 	 */
900 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
901 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
902 			   MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
903 			   regval);
904 	regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
905 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
906 			   MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
907 			   regval);
908 
909 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
910 			MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW);
911 
912 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
913 			MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW);
914 
915 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
916 			MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW);
917 
918 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
919 			MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW);
920 
921 	/*
922 	 * set up the input channel muxes in MESON_SAR_ADC_AUX_SW
923 	 * (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
924 	 * MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
925 	 * MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
926 	 */
927 	regval = 0;
928 	for (i = 2; i <= 7; i++)
929 		regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
930 	regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
931 	regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
932 	regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
933 
934 	if (priv->temperature_sensor_calibrated) {
935 		regmap_set_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
936 				MESON_SAR_ADC_DELTA_10_TS_REVE1);
937 		regmap_set_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
938 				MESON_SAR_ADC_DELTA_10_TS_REVE0);
939 
940 		/*
941 		 * set bits [3:0] of the TSC (temperature sensor coefficient)
942 		 * to get the correct values when reading the temperature.
943 		 */
944 		regval = FIELD_PREP(MESON_SAR_ADC_DELTA_10_TS_C_MASK,
945 				    priv->temperature_sensor_coefficient);
946 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
947 				   MESON_SAR_ADC_DELTA_10_TS_C_MASK, regval);
948 
949 		if (priv->param->temperature_trimming_bits == 5) {
950 			if (priv->temperature_sensor_coefficient & BIT(4))
951 				regval = MESON_HHI_DPLL_TOP_0_TSC_BIT4;
952 			else
953 				regval = 0;
954 
955 			/*
956 			 * bit [4] (the 5th bit when starting to count at 1)
957 			 * of the TSC is located in the HHI register area.
958 			 */
959 			regmap_update_bits(priv->tsc_regmap,
960 					   MESON_HHI_DPLL_TOP_0,
961 					   MESON_HHI_DPLL_TOP_0_TSC_BIT4,
962 					   regval);
963 		}
964 	} else {
965 		regmap_clear_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
966 				  MESON_SAR_ADC_DELTA_10_TS_REVE1);
967 		regmap_clear_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
968 				  MESON_SAR_ADC_DELTA_10_TS_REVE0);
969 	}
970 
971 	regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN,
972 			    priv->param->disable_ring_counter);
973 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
974 			   MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN,
975 			   regval);
976 
977 	if (priv->param->regmap_config->max_register >= MESON_SAR_ADC_REG11) {
978 		regval = FIELD_PREP(MESON_SAR_ADC_REG11_EOC, priv->param->adc_eoc);
979 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
980 				   MESON_SAR_ADC_REG11_EOC, regval);
981 
982 		if (priv->param->has_vref_select) {
983 			regval = FIELD_PREP(MESON_SAR_ADC_REG11_VREF_SEL,
984 					    priv->param->vref_select);
985 			regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
986 					   MESON_SAR_ADC_REG11_VREF_SEL, regval);
987 		}
988 
989 		regval = FIELD_PREP(MESON_SAR_ADC_REG11_VREF_VOLTAGE,
990 				    priv->param->vref_voltage);
991 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
992 				   MESON_SAR_ADC_REG11_VREF_VOLTAGE, regval);
993 
994 		regval = FIELD_PREP(MESON_SAR_ADC_REG11_CMV_SEL,
995 				    priv->param->cmv_select);
996 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
997 				   MESON_SAR_ADC_REG11_CMV_SEL, regval);
998 	}
999 
1000 	ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
1001 	if (ret)
1002 		return dev_err_probe(dev, ret, "failed to set adc parent to clkin\n");
1003 
1004 	ret = clk_set_rate(priv->adc_clk, priv->param->clock_rate);
1005 	if (ret)
1006 		return dev_err_probe(dev, ret, "failed to set adc clock rate\n");
1007 
1008 	return 0;
1009 }
1010 
meson_sar_adc_set_bandgap(struct iio_dev * indio_dev,bool on_off)1011 static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off)
1012 {
1013 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1014 
1015 	if (priv->param->regmap_config->max_register >= MESON_SAR_ADC_REG11)
1016 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
1017 				   MESON_SAR_ADC_REG11_BANDGAP_EN,
1018 				   on_off ? MESON_SAR_ADC_REG11_BANDGAP_EN : 0);
1019 	else
1020 		regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
1021 				   MESON_SAR_ADC_DELTA_10_TS_VBG_EN,
1022 				   on_off ? MESON_SAR_ADC_DELTA_10_TS_VBG_EN : 0);
1023 }
1024 
meson_sar_adc_hw_enable(struct iio_dev * indio_dev)1025 static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
1026 {
1027 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1028 	struct device *dev = indio_dev->dev.parent;
1029 	int ret;
1030 	u32 regval;
1031 
1032 	ret = meson_sar_adc_lock(indio_dev);
1033 	if (ret) {
1034 		dev_err(dev, "failed to lock adc\n");
1035 		goto err_lock;
1036 	}
1037 
1038 	ret = regulator_enable(priv->vref);
1039 	if (ret < 0) {
1040 		dev_err(dev, "failed to enable vref regulator\n");
1041 		goto err_vref;
1042 	}
1043 
1044 	regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
1045 	regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
1046 			   MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
1047 
1048 	meson_sar_adc_set_bandgap(indio_dev, true);
1049 
1050 	regmap_set_bits(priv->regmap, MESON_SAR_ADC_REG3,
1051 			MESON_SAR_ADC_REG3_ADC_EN);
1052 
1053 	udelay(5);
1054 
1055 	ret = clk_prepare_enable(priv->adc_clk);
1056 	if (ret) {
1057 		dev_err(dev, "failed to enable adc clk\n");
1058 		goto err_adc_clk;
1059 	}
1060 
1061 	meson_sar_adc_unlock(indio_dev);
1062 
1063 	return 0;
1064 
1065 err_adc_clk:
1066 	regmap_clear_bits(priv->regmap, MESON_SAR_ADC_REG3,
1067 			  MESON_SAR_ADC_REG3_ADC_EN);
1068 	meson_sar_adc_set_bandgap(indio_dev, false);
1069 	regulator_disable(priv->vref);
1070 err_vref:
1071 	meson_sar_adc_unlock(indio_dev);
1072 err_lock:
1073 	return ret;
1074 }
1075 
meson_sar_adc_hw_disable(struct iio_dev * indio_dev)1076 static void meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
1077 {
1078 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1079 	int ret;
1080 
1081 	/*
1082 	 * If taking the lock fails we have to assume that BL30 is broken. The
1083 	 * best we can do then is to release the resources anyhow.
1084 	 */
1085 	ret = meson_sar_adc_lock(indio_dev);
1086 	if (ret)
1087 		dev_err(indio_dev->dev.parent, "Failed to lock ADC (%pE)\n", ERR_PTR(ret));
1088 
1089 	clk_disable_unprepare(priv->adc_clk);
1090 
1091 	regmap_clear_bits(priv->regmap, MESON_SAR_ADC_REG3,
1092 			  MESON_SAR_ADC_REG3_ADC_EN);
1093 
1094 	meson_sar_adc_set_bandgap(indio_dev, false);
1095 
1096 	regulator_disable(priv->vref);
1097 
1098 	if (!ret)
1099 		meson_sar_adc_unlock(indio_dev);
1100 }
1101 
meson_sar_adc_irq(int irq,void * data)1102 static irqreturn_t meson_sar_adc_irq(int irq, void *data)
1103 {
1104 	struct iio_dev *indio_dev = data;
1105 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1106 	unsigned int cnt, threshold;
1107 	u32 regval;
1108 
1109 	regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
1110 	cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
1111 	threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
1112 
1113 	if (cnt < threshold)
1114 		return IRQ_NONE;
1115 
1116 	complete(&priv->done);
1117 
1118 	return IRQ_HANDLED;
1119 }
1120 
meson_sar_adc_calib(struct iio_dev * indio_dev)1121 static int meson_sar_adc_calib(struct iio_dev *indio_dev)
1122 {
1123 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1124 	int ret, nominal0, nominal1, value0, value1;
1125 
1126 	/* use points 25% and 75% for calibration */
1127 	nominal0 = (1 << priv->param->resolution) / 4;
1128 	nominal1 = (1 << priv->param->resolution) * 3 / 4;
1129 
1130 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4);
1131 	usleep_range(10, 20);
1132 	ret = meson_sar_adc_get_sample(indio_dev,
1133 				       find_channel_by_num(indio_dev,
1134 							   NUM_MUX_1_VDD_DIV4),
1135 				       MEAN_AVERAGING, EIGHT_SAMPLES, &value0);
1136 	if (ret < 0)
1137 		goto out;
1138 
1139 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4);
1140 	usleep_range(10, 20);
1141 	ret = meson_sar_adc_get_sample(indio_dev,
1142 				       find_channel_by_num(indio_dev,
1143 							   NUM_MUX_3_VDD_MUL3_DIV4),
1144 				       MEAN_AVERAGING, EIGHT_SAMPLES, &value1);
1145 	if (ret < 0)
1146 		goto out;
1147 
1148 	if (value1 <= value0) {
1149 		ret = -EINVAL;
1150 		goto out;
1151 	}
1152 
1153 	priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
1154 				   value1 - value0);
1155 	priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
1156 					     MILLION);
1157 	ret = 0;
1158 out:
1159 	meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
1160 
1161 	return ret;
1162 }
1163 
read_label(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,char * label)1164 static int read_label(struct iio_dev *indio_dev,
1165 		      struct iio_chan_spec const *chan,
1166 		      char *label)
1167 {
1168 	if (chan->type == IIO_TEMP)
1169 		return sprintf(label, "temp-sensor\n");
1170 	if (chan->type == IIO_VOLTAGE && chan->channel >= NUM_MUX_0_VSS)
1171 		return sprintf(label, "%s\n",
1172 			       chan7_mux_names[chan->channel - NUM_MUX_0_VSS]);
1173 	if (chan->type == IIO_VOLTAGE)
1174 		return sprintf(label, "channel-%d\n", chan->channel);
1175 	return 0;
1176 }
1177 
1178 static const struct iio_info meson_sar_adc_iio_info = {
1179 	.read_raw = meson_sar_adc_iio_info_read_raw,
1180 	.read_label = read_label,
1181 };
1182 
1183 static const struct meson_sar_adc_param meson_sar_adc_meson8_param = {
1184 	.has_bl30_integration = false,
1185 	.clock_rate = 1150000,
1186 	.regmap_config = &meson_sar_adc_regmap_config_meson8,
1187 	.resolution = 10,
1188 	.temperature_trimming_bits = 4,
1189 	.temperature_multiplier = 18 * 10000,
1190 	.temperature_divider = 1024 * 10 * 85,
1191 };
1192 
1193 static const struct meson_sar_adc_param meson_sar_adc_meson8b_param = {
1194 	.has_bl30_integration = false,
1195 	.clock_rate = 1150000,
1196 	.regmap_config = &meson_sar_adc_regmap_config_meson8,
1197 	.resolution = 10,
1198 	.temperature_trimming_bits = 5,
1199 	.temperature_multiplier = 10,
1200 	.temperature_divider = 32,
1201 };
1202 
1203 static const struct meson_sar_adc_param meson_sar_adc_gxbb_param = {
1204 	.has_bl30_integration = true,
1205 	.clock_rate = 1200000,
1206 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1207 	.resolution = 10,
1208 	.vref_voltage = 1,
1209 	.cmv_select = 1,
1210 };
1211 
1212 static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
1213 	.has_bl30_integration = true,
1214 	.clock_rate = 1200000,
1215 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1216 	.resolution = 12,
1217 	.disable_ring_counter = 1,
1218 	.vref_voltage = 1,
1219 	.cmv_select = 1,
1220 };
1221 
1222 static const struct meson_sar_adc_param meson_sar_adc_axg_param = {
1223 	.has_bl30_integration = true,
1224 	.clock_rate = 1200000,
1225 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1226 	.resolution = 12,
1227 	.disable_ring_counter = 1,
1228 	.vref_voltage = 1,
1229 	.has_vref_select = true,
1230 	.vref_select = VREF_VDDA,
1231 	.cmv_select = 1,
1232 };
1233 
1234 static const struct meson_sar_adc_param meson_sar_adc_g12a_param = {
1235 	.has_bl30_integration = false,
1236 	.clock_rate = 1200000,
1237 	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
1238 	.resolution = 12,
1239 	.disable_ring_counter = 1,
1240 	.adc_eoc = 1,
1241 	.has_vref_select = true,
1242 	.vref_select = VREF_VDDA,
1243 };
1244 
1245 static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
1246 	.param = &meson_sar_adc_meson8_param,
1247 	.name = "meson-meson8-saradc",
1248 };
1249 
1250 static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
1251 	.param = &meson_sar_adc_meson8b_param,
1252 	.name = "meson-meson8b-saradc",
1253 };
1254 
1255 static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
1256 	.param = &meson_sar_adc_meson8b_param,
1257 	.name = "meson-meson8m2-saradc",
1258 };
1259 
1260 static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
1261 	.param = &meson_sar_adc_gxbb_param,
1262 	.name = "meson-gxbb-saradc",
1263 };
1264 
1265 static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
1266 	.param = &meson_sar_adc_gxl_param,
1267 	.name = "meson-gxl-saradc",
1268 };
1269 
1270 static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
1271 	.param = &meson_sar_adc_gxl_param,
1272 	.name = "meson-gxm-saradc",
1273 };
1274 
1275 static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
1276 	.param = &meson_sar_adc_axg_param,
1277 	.name = "meson-axg-saradc",
1278 };
1279 
1280 static const struct meson_sar_adc_data meson_sar_adc_g12a_data = {
1281 	.param = &meson_sar_adc_g12a_param,
1282 	.name = "meson-g12a-saradc",
1283 };
1284 
1285 static const struct of_device_id meson_sar_adc_of_match[] = {
1286 	{
1287 		.compatible = "amlogic,meson8-saradc",
1288 		.data = &meson_sar_adc_meson8_data,
1289 	}, {
1290 		.compatible = "amlogic,meson8b-saradc",
1291 		.data = &meson_sar_adc_meson8b_data,
1292 	}, {
1293 		.compatible = "amlogic,meson8m2-saradc",
1294 		.data = &meson_sar_adc_meson8m2_data,
1295 	}, {
1296 		.compatible = "amlogic,meson-gxbb-saradc",
1297 		.data = &meson_sar_adc_gxbb_data,
1298 	}, {
1299 		.compatible = "amlogic,meson-gxl-saradc",
1300 		.data = &meson_sar_adc_gxl_data,
1301 	}, {
1302 		.compatible = "amlogic,meson-gxm-saradc",
1303 		.data = &meson_sar_adc_gxm_data,
1304 	}, {
1305 		.compatible = "amlogic,meson-axg-saradc",
1306 		.data = &meson_sar_adc_axg_data,
1307 	}, {
1308 		.compatible = "amlogic,meson-g12a-saradc",
1309 		.data = &meson_sar_adc_g12a_data,
1310 	},
1311 	{ /* sentinel */ }
1312 };
1313 MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match);
1314 
meson_sar_adc_probe(struct platform_device * pdev)1315 static int meson_sar_adc_probe(struct platform_device *pdev)
1316 {
1317 	const struct meson_sar_adc_data *match_data;
1318 	struct meson_sar_adc_priv *priv;
1319 	struct device *dev = &pdev->dev;
1320 	struct iio_dev *indio_dev;
1321 	void __iomem *base;
1322 	int irq, ret;
1323 
1324 	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
1325 	if (!indio_dev)
1326 		return dev_err_probe(dev, -ENOMEM, "failed allocating iio device\n");
1327 
1328 	priv = iio_priv(indio_dev);
1329 	init_completion(&priv->done);
1330 
1331 	match_data = of_device_get_match_data(dev);
1332 	if (!match_data)
1333 		return dev_err_probe(dev, -ENODEV, "failed to get match data\n");
1334 
1335 	priv->param = match_data->param;
1336 
1337 	indio_dev->name = match_data->name;
1338 	indio_dev->modes = INDIO_DIRECT_MODE;
1339 	indio_dev->info = &meson_sar_adc_iio_info;
1340 
1341 	base = devm_platform_ioremap_resource(pdev, 0);
1342 	if (IS_ERR(base))
1343 		return PTR_ERR(base);
1344 
1345 	priv->regmap = devm_regmap_init_mmio(dev, base, priv->param->regmap_config);
1346 	if (IS_ERR(priv->regmap))
1347 		return dev_err_probe(dev, PTR_ERR(priv->regmap), "failed to init regmap\n");
1348 
1349 	irq = irq_of_parse_and_map(dev->of_node, 0);
1350 	if (!irq)
1351 		return dev_err_probe(dev, -EINVAL, "failed to get irq\n");
1352 
1353 	ret = devm_request_irq(dev, irq, meson_sar_adc_irq, IRQF_SHARED, dev_name(dev), indio_dev);
1354 	if (ret)
1355 		return dev_err_probe(dev, ret, "failed to request irq\n");
1356 
1357 	priv->clkin = devm_clk_get(dev, "clkin");
1358 	if (IS_ERR(priv->clkin))
1359 		return dev_err_probe(dev, PTR_ERR(priv->clkin), "failed to get clkin\n");
1360 
1361 	priv->core_clk = devm_clk_get_enabled(dev, "core");
1362 	if (IS_ERR(priv->core_clk))
1363 		return dev_err_probe(dev, PTR_ERR(priv->core_clk), "failed to get core clk\n");
1364 
1365 	priv->adc_clk = devm_clk_get_optional(dev, "adc_clk");
1366 	if (IS_ERR(priv->adc_clk))
1367 		return dev_err_probe(dev, PTR_ERR(priv->adc_clk), "failed to get adc clk\n");
1368 
1369 	priv->adc_sel_clk = devm_clk_get_optional(dev, "adc_sel");
1370 	if (IS_ERR(priv->adc_sel_clk))
1371 		return dev_err_probe(dev, PTR_ERR(priv->adc_sel_clk), "failed to get adc_sel clk\n");
1372 
1373 	/* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */
1374 	if (!priv->adc_clk) {
1375 		ret = meson_sar_adc_clk_init(indio_dev, base);
1376 		if (ret)
1377 			return dev_err_probe(dev, ret, "failed to init internal clk\n");
1378 	}
1379 
1380 	priv->vref = devm_regulator_get(dev, "vref");
1381 	if (IS_ERR(priv->vref))
1382 		return dev_err_probe(dev, PTR_ERR(priv->vref), "failed to get vref regulator\n");
1383 
1384 	priv->calibscale = MILLION;
1385 
1386 	if (priv->param->temperature_trimming_bits) {
1387 		ret = meson_sar_adc_temp_sensor_init(indio_dev);
1388 		if (ret)
1389 			return ret;
1390 	}
1391 
1392 	if (priv->temperature_sensor_calibrated) {
1393 		indio_dev->channels = meson_sar_adc_and_temp_iio_channels;
1394 		indio_dev->num_channels =
1395 			ARRAY_SIZE(meson_sar_adc_and_temp_iio_channels);
1396 	} else {
1397 		indio_dev->channels = meson_sar_adc_iio_channels;
1398 		indio_dev->num_channels =
1399 			ARRAY_SIZE(meson_sar_adc_iio_channels);
1400 	}
1401 
1402 	ret = meson_sar_adc_init(indio_dev);
1403 	if (ret)
1404 		goto err;
1405 
1406 	mutex_init(&priv->lock);
1407 
1408 	ret = meson_sar_adc_hw_enable(indio_dev);
1409 	if (ret)
1410 		goto err;
1411 
1412 	ret = meson_sar_adc_calib(indio_dev);
1413 	if (ret)
1414 		dev_warn(dev, "calibration failed\n");
1415 
1416 	platform_set_drvdata(pdev, indio_dev);
1417 
1418 	ret = iio_device_register(indio_dev);
1419 	if (ret) {
1420 		dev_err_probe(dev, ret, "failed to register iio device\n");
1421 		goto err_hw;
1422 	}
1423 
1424 	return 0;
1425 
1426 err_hw:
1427 	meson_sar_adc_hw_disable(indio_dev);
1428 err:
1429 	return ret;
1430 }
1431 
meson_sar_adc_remove(struct platform_device * pdev)1432 static void meson_sar_adc_remove(struct platform_device *pdev)
1433 {
1434 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
1435 
1436 	iio_device_unregister(indio_dev);
1437 
1438 	meson_sar_adc_hw_disable(indio_dev);
1439 }
1440 
meson_sar_adc_suspend(struct device * dev)1441 static int meson_sar_adc_suspend(struct device *dev)
1442 {
1443 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1444 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1445 
1446 	meson_sar_adc_hw_disable(indio_dev);
1447 
1448 	clk_disable_unprepare(priv->core_clk);
1449 
1450 	return 0;
1451 }
1452 
meson_sar_adc_resume(struct device * dev)1453 static int meson_sar_adc_resume(struct device *dev)
1454 {
1455 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1456 	struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
1457 	int ret;
1458 
1459 	ret = clk_prepare_enable(priv->core_clk);
1460 	if (ret) {
1461 		dev_err(dev, "failed to enable core clk\n");
1462 		return ret;
1463 	}
1464 
1465 	return meson_sar_adc_hw_enable(indio_dev);
1466 }
1467 
1468 static DEFINE_SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops,
1469 				meson_sar_adc_suspend, meson_sar_adc_resume);
1470 
1471 static struct platform_driver meson_sar_adc_driver = {
1472 	.probe		= meson_sar_adc_probe,
1473 	.remove		= meson_sar_adc_remove,
1474 	.driver		= {
1475 		.name	= "meson-saradc",
1476 		.of_match_table = meson_sar_adc_of_match,
1477 		.pm = pm_sleep_ptr(&meson_sar_adc_pm_ops),
1478 	},
1479 };
1480 
1481 module_platform_driver(meson_sar_adc_driver);
1482 
1483 MODULE_AUTHOR("Martin Blumenstingl <[email protected]>");
1484 MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver");
1485 MODULE_LICENSE("GPL v2");
1486