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16#include <linux/module.h>
17#include <linux/platform_device.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/of.h>
21#include <linux/of_device.h>
22#include <linux/clk.h>
23#include <linux/completion.h>
24#include <linux/delay.h>
25#include <linux/reset.h>
26#include <linux/regulator/consumer.h>
27#include <linux/iio/iio.h>
28
29#define SARADC_DATA 0x00
30
31#define SARADC_STAS 0x04
32#define SARADC_STAS_BUSY BIT(0)
33
34#define SARADC_CTRL 0x08
35#define SARADC_CTRL_IRQ_STATUS BIT(6)
36#define SARADC_CTRL_IRQ_ENABLE BIT(5)
37#define SARADC_CTRL_POWER_CTRL BIT(3)
38#define SARADC_CTRL_CHN_MASK 0x7
39
40#define SARADC_DLY_PU_SOC 0x0c
41#define SARADC_DLY_PU_SOC_MASK 0x3f
42
43#define SARADC_TIMEOUT msecs_to_jiffies(100)
44
45struct rockchip_saradc_data {
46 int num_bits;
47 const struct iio_chan_spec *channels;
48 int num_channels;
49 unsigned long clk_rate;
50};
51
52struct rockchip_saradc {
53 void __iomem *regs;
54 struct clk *pclk;
55 struct clk *clk;
56 struct completion completion;
57 struct regulator *vref;
58 struct reset_control *reset;
59 const struct rockchip_saradc_data *data;
60 u16 last_val;
61};
62
63static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
64 struct iio_chan_spec const *chan,
65 int *val, int *val2, long mask)
66{
67 struct rockchip_saradc *info = iio_priv(indio_dev);
68 int ret;
69
70 switch (mask) {
71 case IIO_CHAN_INFO_RAW:
72 mutex_lock(&indio_dev->mlock);
73
74 reinit_completion(&info->completion);
75
76
77 writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
78
79
80 writel(SARADC_CTRL_POWER_CTRL
81 | (chan->channel & SARADC_CTRL_CHN_MASK)
82 | SARADC_CTRL_IRQ_ENABLE,
83 info->regs + SARADC_CTRL);
84
85 if (!wait_for_completion_timeout(&info->completion,
86 SARADC_TIMEOUT)) {
87 writel_relaxed(0, info->regs + SARADC_CTRL);
88 mutex_unlock(&indio_dev->mlock);
89 return -ETIMEDOUT;
90 }
91
92 *val = info->last_val;
93 mutex_unlock(&indio_dev->mlock);
94 return IIO_VAL_INT;
95 case IIO_CHAN_INFO_SCALE:
96 ret = regulator_get_voltage(info->vref);
97 if (ret < 0) {
98 dev_err(&indio_dev->dev, "failed to get voltage\n");
99 return ret;
100 }
101
102 *val = ret / 1000;
103 *val2 = info->data->num_bits;
104 return IIO_VAL_FRACTIONAL_LOG2;
105 default:
106 return -EINVAL;
107 }
108}
109
110static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
111{
112 struct rockchip_saradc *info = dev_id;
113
114
115 info->last_val = readl_relaxed(info->regs + SARADC_DATA);
116 info->last_val &= GENMASK(info->data->num_bits - 1, 0);
117
118
119 writel_relaxed(0, info->regs + SARADC_CTRL);
120
121 complete(&info->completion);
122
123 return IRQ_HANDLED;
124}
125
126static const struct iio_info rockchip_saradc_iio_info = {
127 .read_raw = rockchip_saradc_read_raw,
128 .driver_module = THIS_MODULE,
129};
130
131#define ADC_CHANNEL(_index, _id) { \
132 .type = IIO_VOLTAGE, \
133 .indexed = 1, \
134 .channel = _index, \
135 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
136 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
137 .datasheet_name = _id, \
138}
139
140static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
141 ADC_CHANNEL(0, "adc0"),
142 ADC_CHANNEL(1, "adc1"),
143 ADC_CHANNEL(2, "adc2"),
144};
145
146static const struct rockchip_saradc_data saradc_data = {
147 .num_bits = 10,
148 .channels = rockchip_saradc_iio_channels,
149 .num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels),
150 .clk_rate = 1000000,
151};
152
153static const struct iio_chan_spec rockchip_rk3066_tsadc_iio_channels[] = {
154 ADC_CHANNEL(0, "adc0"),
155 ADC_CHANNEL(1, "adc1"),
156};
157
158static const struct rockchip_saradc_data rk3066_tsadc_data = {
159 .num_bits = 12,
160 .channels = rockchip_rk3066_tsadc_iio_channels,
161 .num_channels = ARRAY_SIZE(rockchip_rk3066_tsadc_iio_channels),
162 .clk_rate = 50000,
163};
164
165static const struct iio_chan_spec rockchip_rk3399_saradc_iio_channels[] = {
166 ADC_CHANNEL(0, "adc0"),
167 ADC_CHANNEL(1, "adc1"),
168 ADC_CHANNEL(2, "adc2"),
169 ADC_CHANNEL(3, "adc3"),
170 ADC_CHANNEL(4, "adc4"),
171 ADC_CHANNEL(5, "adc5"),
172};
173
174static const struct rockchip_saradc_data rk3399_saradc_data = {
175 .num_bits = 10,
176 .channels = rockchip_rk3399_saradc_iio_channels,
177 .num_channels = ARRAY_SIZE(rockchip_rk3399_saradc_iio_channels),
178 .clk_rate = 1000000,
179};
180
181static const struct of_device_id rockchip_saradc_match[] = {
182 {
183 .compatible = "rockchip,saradc",
184 .data = &saradc_data,
185 }, {
186 .compatible = "rockchip,rk3066-tsadc",
187 .data = &rk3066_tsadc_data,
188 }, {
189 .compatible = "rockchip,rk3399-saradc",
190 .data = &rk3399_saradc_data,
191 },
192 {},
193};
194MODULE_DEVICE_TABLE(of, rockchip_saradc_match);
195
196
197
198
199static void rockchip_saradc_reset_controller(struct reset_control *reset)
200{
201 reset_control_assert(reset);
202 usleep_range(10, 20);
203 reset_control_deassert(reset);
204}
205
206static int rockchip_saradc_probe(struct platform_device *pdev)
207{
208 struct rockchip_saradc *info = NULL;
209 struct device_node *np = pdev->dev.of_node;
210 struct iio_dev *indio_dev = NULL;
211 struct resource *mem;
212 const struct of_device_id *match;
213 int ret;
214 int irq;
215
216 if (!np)
217 return -ENODEV;
218
219 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
220 if (!indio_dev) {
221 dev_err(&pdev->dev, "failed allocating iio device\n");
222 return -ENOMEM;
223 }
224 info = iio_priv(indio_dev);
225
226 match = of_match_device(rockchip_saradc_match, &pdev->dev);
227 if (!match) {
228 dev_err(&pdev->dev, "failed to match device\n");
229 return -ENODEV;
230 }
231
232 info->data = match->data;
233
234 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
235 info->regs = devm_ioremap_resource(&pdev->dev, mem);
236 if (IS_ERR(info->regs))
237 return PTR_ERR(info->regs);
238
239
240
241
242
243 info->reset = devm_reset_control_get_exclusive(&pdev->dev,
244 "saradc-apb");
245 if (IS_ERR(info->reset)) {
246 ret = PTR_ERR(info->reset);
247 if (ret != -ENOENT)
248 return ret;
249
250 dev_dbg(&pdev->dev, "no reset control found\n");
251 info->reset = NULL;
252 }
253
254 init_completion(&info->completion);
255
256 irq = platform_get_irq(pdev, 0);
257 if (irq < 0) {
258 dev_err(&pdev->dev, "no irq resource?\n");
259 return irq;
260 }
261
262 ret = devm_request_irq(&pdev->dev, irq, rockchip_saradc_isr,
263 0, dev_name(&pdev->dev), info);
264 if (ret < 0) {
265 dev_err(&pdev->dev, "failed requesting irq %d\n", irq);
266 return ret;
267 }
268
269 info->pclk = devm_clk_get(&pdev->dev, "apb_pclk");
270 if (IS_ERR(info->pclk)) {
271 dev_err(&pdev->dev, "failed to get pclk\n");
272 return PTR_ERR(info->pclk);
273 }
274
275 info->clk = devm_clk_get(&pdev->dev, "saradc");
276 if (IS_ERR(info->clk)) {
277 dev_err(&pdev->dev, "failed to get adc clock\n");
278 return PTR_ERR(info->clk);
279 }
280
281 info->vref = devm_regulator_get(&pdev->dev, "vref");
282 if (IS_ERR(info->vref)) {
283 dev_err(&pdev->dev, "failed to get regulator, %ld\n",
284 PTR_ERR(info->vref));
285 return PTR_ERR(info->vref);
286 }
287
288 if (info->reset)
289 rockchip_saradc_reset_controller(info->reset);
290
291
292
293
294
295 ret = clk_set_rate(info->clk, info->data->clk_rate);
296 if (ret < 0) {
297 dev_err(&pdev->dev, "failed to set adc clk rate, %d\n", ret);
298 return ret;
299 }
300
301 ret = regulator_enable(info->vref);
302 if (ret < 0) {
303 dev_err(&pdev->dev, "failed to enable vref regulator\n");
304 return ret;
305 }
306
307 ret = clk_prepare_enable(info->pclk);
308 if (ret < 0) {
309 dev_err(&pdev->dev, "failed to enable pclk\n");
310 goto err_reg_voltage;
311 }
312
313 ret = clk_prepare_enable(info->clk);
314 if (ret < 0) {
315 dev_err(&pdev->dev, "failed to enable converter clock\n");
316 goto err_pclk;
317 }
318
319 platform_set_drvdata(pdev, indio_dev);
320
321 indio_dev->name = dev_name(&pdev->dev);
322 indio_dev->dev.parent = &pdev->dev;
323 indio_dev->dev.of_node = pdev->dev.of_node;
324 indio_dev->info = &rockchip_saradc_iio_info;
325 indio_dev->modes = INDIO_DIRECT_MODE;
326
327 indio_dev->channels = info->data->channels;
328 indio_dev->num_channels = info->data->num_channels;
329
330 ret = iio_device_register(indio_dev);
331 if (ret)
332 goto err_clk;
333
334 return 0;
335
336err_clk:
337 clk_disable_unprepare(info->clk);
338err_pclk:
339 clk_disable_unprepare(info->pclk);
340err_reg_voltage:
341 regulator_disable(info->vref);
342 return ret;
343}
344
345static int rockchip_saradc_remove(struct platform_device *pdev)
346{
347 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
348 struct rockchip_saradc *info = iio_priv(indio_dev);
349
350 iio_device_unregister(indio_dev);
351 clk_disable_unprepare(info->clk);
352 clk_disable_unprepare(info->pclk);
353 regulator_disable(info->vref);
354
355 return 0;
356}
357
358#ifdef CONFIG_PM_SLEEP
359static int rockchip_saradc_suspend(struct device *dev)
360{
361 struct iio_dev *indio_dev = dev_get_drvdata(dev);
362 struct rockchip_saradc *info = iio_priv(indio_dev);
363
364 clk_disable_unprepare(info->clk);
365 clk_disable_unprepare(info->pclk);
366 regulator_disable(info->vref);
367
368 return 0;
369}
370
371static int rockchip_saradc_resume(struct device *dev)
372{
373 struct iio_dev *indio_dev = dev_get_drvdata(dev);
374 struct rockchip_saradc *info = iio_priv(indio_dev);
375 int ret;
376
377 ret = regulator_enable(info->vref);
378 if (ret)
379 return ret;
380
381 ret = clk_prepare_enable(info->pclk);
382 if (ret)
383 return ret;
384
385 ret = clk_prepare_enable(info->clk);
386 if (ret)
387 return ret;
388
389 return ret;
390}
391#endif
392
393static SIMPLE_DEV_PM_OPS(rockchip_saradc_pm_ops,
394 rockchip_saradc_suspend, rockchip_saradc_resume);
395
396static struct platform_driver rockchip_saradc_driver = {
397 .probe = rockchip_saradc_probe,
398 .remove = rockchip_saradc_remove,
399 .driver = {
400 .name = "rockchip-saradc",
401 .of_match_table = rockchip_saradc_match,
402 .pm = &rockchip_saradc_pm_ops,
403 },
404};
405
406module_platform_driver(rockchip_saradc_driver);
407
408MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
409MODULE_DESCRIPTION("Rockchip SARADC driver");
410MODULE_LICENSE("GPL v2");
411