1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Freescale Vybrid vf610 DAC driver
4 *
5 * Copyright 2016 Toradex AG
6 */
7
8#include <linux/clk.h>
9#include <linux/err.h>
10#include <linux/interrupt.h>
11#include <linux/io.h>
12#include <linux/kernel.h>
13#include <linux/mod_devicetable.h>
14#include <linux/module.h>
15#include <linux/platform_device.h>
16#include <linux/regulator/consumer.h>
17#include <linux/slab.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21
22#define VF610_DACx_STATCTRL 0x20
23
24#define VF610_DAC_DACEN BIT(15)
25#define VF610_DAC_DACRFS BIT(14)
26#define VF610_DAC_LPEN BIT(11)
27
28#define VF610_DAC_DAT0(x) ((x) & 0xFFF)
29
30enum vf610_conversion_mode_sel {
31 VF610_DAC_CONV_HIGH_POWER,
32 VF610_DAC_CONV_LOW_POWER,
33};
34
35struct vf610_dac {
36 struct clk *clk;
37 struct device *dev;
38 enum vf610_conversion_mode_sel conv_mode;
39 void __iomem *regs;
40 struct mutex lock;
41};
42
43static void vf610_dac_init(struct vf610_dac *info)
44{
45 int val;
46
47 info->conv_mode = VF610_DAC_CONV_LOW_POWER;
48 val = VF610_DAC_DACEN | VF610_DAC_DACRFS |
49 VF610_DAC_LPEN;
50 writel(val, addr: info->regs + VF610_DACx_STATCTRL);
51}
52
53static void vf610_dac_exit(struct vf610_dac *info)
54{
55 int val;
56
57 val = readl(addr: info->regs + VF610_DACx_STATCTRL);
58 val &= ~VF610_DAC_DACEN;
59 writel(val, addr: info->regs + VF610_DACx_STATCTRL);
60}
61
62static int vf610_set_conversion_mode(struct iio_dev *indio_dev,
63 const struct iio_chan_spec *chan,
64 unsigned int mode)
65{
66 struct vf610_dac *info = iio_priv(indio_dev);
67 int val;
68
69 mutex_lock(&info->lock);
70 info->conv_mode = mode;
71 val = readl(addr: info->regs + VF610_DACx_STATCTRL);
72 if (mode)
73 val |= VF610_DAC_LPEN;
74 else
75 val &= ~VF610_DAC_LPEN;
76 writel(val, addr: info->regs + VF610_DACx_STATCTRL);
77 mutex_unlock(lock: &info->lock);
78
79 return 0;
80}
81
82static int vf610_get_conversion_mode(struct iio_dev *indio_dev,
83 const struct iio_chan_spec *chan)
84{
85 struct vf610_dac *info = iio_priv(indio_dev);
86
87 return info->conv_mode;
88}
89
90static const char * const vf610_conv_modes[] = { "high-power", "low-power" };
91
92static const struct iio_enum vf610_conversion_mode = {
93 .items = vf610_conv_modes,
94 .num_items = ARRAY_SIZE(vf610_conv_modes),
95 .get = vf610_get_conversion_mode,
96 .set = vf610_set_conversion_mode,
97};
98
99static const struct iio_chan_spec_ext_info vf610_ext_info[] = {
100 IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR,
101 &vf610_conversion_mode),
102 {},
103};
104
105#define VF610_DAC_CHAN(_chan_type) { \
106 .type = (_chan_type), \
107 .output = 1, \
108 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
109 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
110 .ext_info = vf610_ext_info, \
111}
112
113static const struct iio_chan_spec vf610_dac_iio_channels[] = {
114 VF610_DAC_CHAN(IIO_VOLTAGE),
115};
116
117static int vf610_read_raw(struct iio_dev *indio_dev,
118 struct iio_chan_spec const *chan,
119 int *val, int *val2,
120 long mask)
121{
122 struct vf610_dac *info = iio_priv(indio_dev);
123
124 switch (mask) {
125 case IIO_CHAN_INFO_RAW:
126 *val = VF610_DAC_DAT0(readl(info->regs));
127 return IIO_VAL_INT;
128 case IIO_CHAN_INFO_SCALE:
129 /*
130 * DACRFS is always 1 for valid reference and typical
131 * reference voltage as per Vybrid datasheet is 3.3V
132 * from section 9.1.2.1 of Vybrid datasheet
133 */
134 *val = 3300 /* mV */;
135 *val2 = 12;
136 return IIO_VAL_FRACTIONAL_LOG2;
137
138 default:
139 return -EINVAL;
140 }
141}
142
143static int vf610_write_raw(struct iio_dev *indio_dev,
144 struct iio_chan_spec const *chan,
145 int val, int val2,
146 long mask)
147{
148 struct vf610_dac *info = iio_priv(indio_dev);
149
150 switch (mask) {
151 case IIO_CHAN_INFO_RAW:
152 mutex_lock(&info->lock);
153 writel(VF610_DAC_DAT0(val), addr: info->regs);
154 mutex_unlock(lock: &info->lock);
155 return 0;
156
157 default:
158 return -EINVAL;
159 }
160}
161
162static const struct iio_info vf610_dac_iio_info = {
163 .read_raw = &vf610_read_raw,
164 .write_raw = &vf610_write_raw,
165};
166
167static const struct of_device_id vf610_dac_match[] = {
168 { .compatible = "fsl,vf610-dac", },
169 { /* sentinel */ }
170};
171MODULE_DEVICE_TABLE(of, vf610_dac_match);
172
173static int vf610_dac_probe(struct platform_device *pdev)
174{
175 struct iio_dev *indio_dev;
176 struct vf610_dac *info;
177 int ret;
178
179 indio_dev = devm_iio_device_alloc(parent: &pdev->dev,
180 sizeof_priv: sizeof(struct vf610_dac));
181 if (!indio_dev) {
182 dev_err(&pdev->dev, "Failed allocating iio device\n");
183 return -ENOMEM;
184 }
185
186 info = iio_priv(indio_dev);
187 info->dev = &pdev->dev;
188
189 info->regs = devm_platform_ioremap_resource(pdev, index: 0);
190 if (IS_ERR(ptr: info->regs))
191 return PTR_ERR(ptr: info->regs);
192
193 info->clk = devm_clk_get(dev: &pdev->dev, id: "dac");
194 if (IS_ERR(ptr: info->clk)) {
195 dev_err(&pdev->dev, "Failed getting clock, err = %ld\n",
196 PTR_ERR(info->clk));
197 return PTR_ERR(ptr: info->clk);
198 }
199
200 platform_set_drvdata(pdev, data: indio_dev);
201
202 indio_dev->name = dev_name(dev: &pdev->dev);
203 indio_dev->info = &vf610_dac_iio_info;
204 indio_dev->modes = INDIO_DIRECT_MODE;
205 indio_dev->channels = vf610_dac_iio_channels;
206 indio_dev->num_channels = ARRAY_SIZE(vf610_dac_iio_channels);
207
208 mutex_init(&info->lock);
209
210 ret = clk_prepare_enable(clk: info->clk);
211 if (ret) {
212 dev_err(&pdev->dev,
213 "Could not prepare or enable the clock\n");
214 return ret;
215 }
216
217 vf610_dac_init(info);
218
219 ret = iio_device_register(indio_dev);
220 if (ret) {
221 dev_err(&pdev->dev, "Couldn't register the device\n");
222 goto error_iio_device_register;
223 }
224
225 return 0;
226
227error_iio_device_register:
228 vf610_dac_exit(info);
229 clk_disable_unprepare(clk: info->clk);
230
231 return ret;
232}
233
234static void vf610_dac_remove(struct platform_device *pdev)
235{
236 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
237 struct vf610_dac *info = iio_priv(indio_dev);
238
239 iio_device_unregister(indio_dev);
240 vf610_dac_exit(info);
241 clk_disable_unprepare(clk: info->clk);
242}
243
244static int vf610_dac_suspend(struct device *dev)
245{
246 struct iio_dev *indio_dev = dev_get_drvdata(dev);
247 struct vf610_dac *info = iio_priv(indio_dev);
248
249 vf610_dac_exit(info);
250 clk_disable_unprepare(clk: info->clk);
251
252 return 0;
253}
254
255static int vf610_dac_resume(struct device *dev)
256{
257 struct iio_dev *indio_dev = dev_get_drvdata(dev);
258 struct vf610_dac *info = iio_priv(indio_dev);
259 int ret;
260
261 ret = clk_prepare_enable(clk: info->clk);
262 if (ret)
263 return ret;
264
265 vf610_dac_init(info);
266
267 return 0;
268}
269
270static DEFINE_SIMPLE_DEV_PM_OPS(vf610_dac_pm_ops, vf610_dac_suspend,
271 vf610_dac_resume);
272
273static struct platform_driver vf610_dac_driver = {
274 .probe = vf610_dac_probe,
275 .remove_new = vf610_dac_remove,
276 .driver = {
277 .name = "vf610-dac",
278 .of_match_table = vf610_dac_match,
279 .pm = pm_sleep_ptr(&vf610_dac_pm_ops),
280 },
281};
282module_platform_driver(vf610_dac_driver);
283
284MODULE_AUTHOR("Sanchayan Maity <sanchayan.maity@toradex.com>");
285MODULE_DESCRIPTION("Freescale VF610 DAC driver");
286MODULE_LICENSE("GPL v2");
287

source code of linux/drivers/iio/dac/vf610_dac.c