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13#include <linux/err.h>
14#include <linux/i2c.h>
15#include <linux/mfd/lp3943.h>
16#include <linux/module.h>
17#include <linux/platform_device.h>
18#include <linux/pwm.h>
19#include <linux/slab.h>
20
21#define LP3943_MAX_DUTY 255
22#define LP3943_MIN_PERIOD 6250
23#define LP3943_MAX_PERIOD 1600000
24
25struct lp3943_pwm {
26 struct pwm_chip chip;
27 struct lp3943 *lp3943;
28 struct lp3943_platform_data *pdata;
29};
30
31static inline struct lp3943_pwm *to_lp3943_pwm(struct pwm_chip *_chip)
32{
33 return container_of(_chip, struct lp3943_pwm, chip);
34}
35
36static struct lp3943_pwm_map *
37lp3943_pwm_request_map(struct lp3943_pwm *lp3943_pwm, int hwpwm)
38{
39 struct lp3943_platform_data *pdata = lp3943_pwm->pdata;
40 struct lp3943 *lp3943 = lp3943_pwm->lp3943;
41 struct lp3943_pwm_map *pwm_map;
42 int i, offset;
43
44 pwm_map = kzalloc(sizeof(*pwm_map), GFP_KERNEL);
45 if (!pwm_map)
46 return ERR_PTR(-ENOMEM);
47
48 pwm_map->output = pdata->pwms[hwpwm]->output;
49 pwm_map->num_outputs = pdata->pwms[hwpwm]->num_outputs;
50
51 for (i = 0; i < pwm_map->num_outputs; i++) {
52 offset = pwm_map->output[i];
53
54
55 if (test_and_set_bit(offset, &lp3943->pin_used)) {
56 kfree(pwm_map);
57 return ERR_PTR(-EBUSY);
58 }
59 }
60
61 return pwm_map;
62}
63
64static int lp3943_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
65{
66 struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
67 struct lp3943_pwm_map *pwm_map;
68
69 pwm_map = lp3943_pwm_request_map(lp3943_pwm, pwm->hwpwm);
70 if (IS_ERR(pwm_map))
71 return PTR_ERR(pwm_map);
72
73 return pwm_set_chip_data(pwm, pwm_map);
74}
75
76static void lp3943_pwm_free_map(struct lp3943_pwm *lp3943_pwm,
77 struct lp3943_pwm_map *pwm_map)
78{
79 struct lp3943 *lp3943 = lp3943_pwm->lp3943;
80 int i, offset;
81
82 for (i = 0; i < pwm_map->num_outputs; i++) {
83 offset = pwm_map->output[i];
84 clear_bit(offset, &lp3943->pin_used);
85 }
86
87 kfree(pwm_map);
88}
89
90static void lp3943_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
91{
92 struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
93 struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
94
95 lp3943_pwm_free_map(lp3943_pwm, pwm_map);
96}
97
98static int lp3943_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
99 int duty_ns, int period_ns)
100{
101 struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
102 struct lp3943 *lp3943 = lp3943_pwm->lp3943;
103 u8 val, reg_duty, reg_prescale;
104 int err;
105
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114
115
116 if (pwm->hwpwm == 0) {
117 reg_prescale = LP3943_REG_PRESCALE0;
118 reg_duty = LP3943_REG_PWM0;
119 } else {
120 reg_prescale = LP3943_REG_PRESCALE1;
121 reg_duty = LP3943_REG_PWM1;
122 }
123
124 period_ns = clamp(period_ns, LP3943_MIN_PERIOD, LP3943_MAX_PERIOD);
125 val = (u8)(period_ns / LP3943_MIN_PERIOD - 1);
126
127 err = lp3943_write_byte(lp3943, reg_prescale, val);
128 if (err)
129 return err;
130
131 val = (u8)(duty_ns * LP3943_MAX_DUTY / period_ns);
132
133 return lp3943_write_byte(lp3943, reg_duty, val);
134}
135
136static int lp3943_pwm_set_mode(struct lp3943_pwm *lp3943_pwm,
137 struct lp3943_pwm_map *pwm_map,
138 u8 val)
139{
140 struct lp3943 *lp3943 = lp3943_pwm->lp3943;
141 const struct lp3943_reg_cfg *mux = lp3943->mux_cfg;
142 int i, index, err;
143
144 for (i = 0; i < pwm_map->num_outputs; i++) {
145 index = pwm_map->output[i];
146 err = lp3943_update_bits(lp3943, mux[index].reg,
147 mux[index].mask,
148 val << mux[index].shift);
149 if (err)
150 return err;
151 }
152
153 return 0;
154}
155
156static int lp3943_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
157{
158 struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
159 struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
160 u8 val;
161
162 if (pwm->hwpwm == 0)
163 val = LP3943_DIM_PWM0;
164 else
165 val = LP3943_DIM_PWM1;
166
167
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170
171
172 return lp3943_pwm_set_mode(lp3943_pwm, pwm_map, val);
173}
174
175static void lp3943_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
176{
177 struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
178 struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
179
180
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182
183
184
185 lp3943_pwm_set_mode(lp3943_pwm, pwm_map, LP3943_GPIO_OUT_HIGH);
186}
187
188static const struct pwm_ops lp3943_pwm_ops = {
189 .request = lp3943_pwm_request,
190 .free = lp3943_pwm_free,
191 .config = lp3943_pwm_config,
192 .enable = lp3943_pwm_enable,
193 .disable = lp3943_pwm_disable,
194 .owner = THIS_MODULE,
195};
196
197static int lp3943_pwm_parse_dt(struct device *dev,
198 struct lp3943_pwm *lp3943_pwm)
199{
200 static const char * const name[] = { "ti,pwm0", "ti,pwm1", };
201 struct device_node *node = dev->of_node;
202 struct lp3943_platform_data *pdata;
203 struct lp3943_pwm_map *pwm_map;
204 enum lp3943_pwm_output *output;
205 int i, err, proplen, count = 0;
206 u32 num_outputs;
207
208 if (!node)
209 return -EINVAL;
210
211 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
212 if (!pdata)
213 return -ENOMEM;
214
215
216
217
218
219
220 for (i = 0; i < LP3943_NUM_PWMS; i++) {
221 if (!of_get_property(node, name[i], &proplen))
222 continue;
223
224 num_outputs = proplen / sizeof(u32);
225 if (num_outputs == 0)
226 continue;
227
228 output = devm_kzalloc(dev, sizeof(*output) * num_outputs,
229 GFP_KERNEL);
230 if (!output)
231 return -ENOMEM;
232
233 err = of_property_read_u32_array(node, name[i], output,
234 num_outputs);
235 if (err)
236 return err;
237
238 pwm_map = devm_kzalloc(dev, sizeof(*pwm_map), GFP_KERNEL);
239 if (!pwm_map)
240 return -ENOMEM;
241
242 pwm_map->output = output;
243 pwm_map->num_outputs = num_outputs;
244 pdata->pwms[i] = pwm_map;
245
246 count++;
247 }
248
249 if (count == 0)
250 return -ENODATA;
251
252 lp3943_pwm->pdata = pdata;
253 return 0;
254}
255
256static int lp3943_pwm_probe(struct platform_device *pdev)
257{
258 struct lp3943 *lp3943 = dev_get_drvdata(pdev->dev.parent);
259 struct lp3943_pwm *lp3943_pwm;
260 int ret;
261
262 lp3943_pwm = devm_kzalloc(&pdev->dev, sizeof(*lp3943_pwm), GFP_KERNEL);
263 if (!lp3943_pwm)
264 return -ENOMEM;
265
266 lp3943_pwm->pdata = lp3943->pdata;
267 if (!lp3943_pwm->pdata) {
268 if (IS_ENABLED(CONFIG_OF))
269 ret = lp3943_pwm_parse_dt(&pdev->dev, lp3943_pwm);
270 else
271 ret = -ENODEV;
272
273 if (ret)
274 return ret;
275 }
276
277 lp3943_pwm->lp3943 = lp3943;
278 lp3943_pwm->chip.dev = &pdev->dev;
279 lp3943_pwm->chip.ops = &lp3943_pwm_ops;
280 lp3943_pwm->chip.npwm = LP3943_NUM_PWMS;
281 lp3943_pwm->chip.can_sleep = true;
282
283 platform_set_drvdata(pdev, lp3943_pwm);
284
285 return pwmchip_add(&lp3943_pwm->chip);
286}
287
288static int lp3943_pwm_remove(struct platform_device *pdev)
289{
290 struct lp3943_pwm *lp3943_pwm = platform_get_drvdata(pdev);
291
292 return pwmchip_remove(&lp3943_pwm->chip);
293}
294
295#ifdef CONFIG_OF
296static const struct of_device_id lp3943_pwm_of_match[] = {
297 { .compatible = "ti,lp3943-pwm", },
298 { }
299};
300MODULE_DEVICE_TABLE(of, lp3943_pwm_of_match);
301#endif
302
303static struct platform_driver lp3943_pwm_driver = {
304 .probe = lp3943_pwm_probe,
305 .remove = lp3943_pwm_remove,
306 .driver = {
307 .name = "lp3943-pwm",
308 .of_match_table = of_match_ptr(lp3943_pwm_of_match),
309 },
310};
311module_platform_driver(lp3943_pwm_driver);
312
313MODULE_DESCRIPTION("LP3943 PWM driver");
314MODULE_ALIAS("platform:lp3943-pwm");
315MODULE_AUTHOR("Milo Kim");
316MODULE_LICENSE("GPL");
317
