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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PWM Controller Driver for HiSilicon BVT SoCs
4 *
5 * Copyright (c) 2016 HiSilicon Technologies Co., Ltd.
6 */
7
8#include <linux/bitops.h>
9#include <linux/clk.h>
10#include <linux/delay.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/pwm.h>
16#include <linux/reset.h>
17
18#define PWM_CFG0_ADDR(x) (((x) * 0x20) + 0x0)
19#define PWM_CFG1_ADDR(x) (((x) * 0x20) + 0x4)
20#define PWM_CFG2_ADDR(x) (((x) * 0x20) + 0x8)
21#define PWM_CTRL_ADDR(x) (((x) * 0x20) + 0xC)
22
23#define PWM_ENABLE_SHIFT 0
24#define PWM_ENABLE_MASK BIT(0)
25
26#define PWM_POLARITY_SHIFT 1
27#define PWM_POLARITY_MASK BIT(1)
28
29#define PWM_KEEP_SHIFT 2
30#define PWM_KEEP_MASK BIT(2)
31
32#define PWM_PERIOD_MASK GENMASK(31, 0)
33#define PWM_DUTY_MASK GENMASK(31, 0)
34
35struct hibvt_pwm_chip {
36 struct clk *clk;
37 void __iomem *base;
38 struct reset_control *rstc;
39 const struct hibvt_pwm_soc *soc;
40};
41
42struct hibvt_pwm_soc {
43 u32 num_pwms;
44 bool quirk_force_enable;
45};
46
47static const struct hibvt_pwm_soc hi3516cv300_soc_info = {
48 .num_pwms = 4,
49};
50
51static const struct hibvt_pwm_soc hi3519v100_soc_info = {
52 .num_pwms = 8,
53};
54
55static const struct hibvt_pwm_soc hi3559v100_shub_soc_info = {
56 .num_pwms = 8,
57 .quirk_force_enable = true,
58};
59
60static const struct hibvt_pwm_soc hi3559v100_soc_info = {
61 .num_pwms = 2,
62 .quirk_force_enable = true,
63};
64
65static inline struct hibvt_pwm_chip *to_hibvt_pwm_chip(struct pwm_chip *chip)
66{
67 return pwmchip_get_drvdata(chip);
68}
69
70static void hibvt_pwm_set_bits(void __iomem *base, u32 offset,
71 u32 mask, u32 data)
72{
73 void __iomem *address = base + offset;
74 u32 value;
75
76 value = readl(address);
77 value &= ~mask;
78 value |= (data & mask);
79 writel(value, address);
80}
81
82static void hibvt_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
83{
84 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
85
86 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm),
87 PWM_ENABLE_MASK, 0x1);
88}
89
90static void hibvt_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
91{
92 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
93
94 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm),
95 PWM_ENABLE_MASK, 0x0);
96}
97
98static void hibvt_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
99 int duty_cycle_ns, int period_ns)
100{
101 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
102 u32 freq, period, duty;
103
104 freq = div_u64(clk_get_rate(hi_pwm_chip->clk), 1000000);
105
106 period = div_u64(freq * period_ns, 1000);
107 duty = div_u64(period * duty_cycle_ns, period_ns);
108
109 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CFG0_ADDR(pwm->hwpwm),
110 PWM_PERIOD_MASK, period);
111
112 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CFG1_ADDR(pwm->hwpwm),
113 PWM_DUTY_MASK, duty);
114}
115
116static void hibvt_pwm_set_polarity(struct pwm_chip *chip,
117 struct pwm_device *pwm,
118 enum pwm_polarity polarity)
119{
120 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
121
122 if (polarity == PWM_POLARITY_INVERSED)
123 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm),
124 PWM_POLARITY_MASK, (0x1 << PWM_POLARITY_SHIFT));
125 else
126 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(pwm->hwpwm),
127 PWM_POLARITY_MASK, (0x0 << PWM_POLARITY_SHIFT));
128}
129
130static int hibvt_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
131 struct pwm_state *state)
132{
133 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
134 void __iomem *base;
135 u32 freq, value;
136
137 freq = div_u64(clk_get_rate(hi_pwm_chip->clk), 1000000);
138 base = hi_pwm_chip->base;
139
140 value = readl(base + PWM_CFG0_ADDR(pwm->hwpwm));
141 state->period = div_u64(value * 1000, freq);
142
143 value = readl(base + PWM_CFG1_ADDR(pwm->hwpwm));
144 state->duty_cycle = div_u64(value * 1000, freq);
145
146 value = readl(base + PWM_CTRL_ADDR(pwm->hwpwm));
147 state->enabled = (PWM_ENABLE_MASK & value);
148 state->polarity = (PWM_POLARITY_MASK & value) ? PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
149
150 return 0;
151}
152
153static int hibvt_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
154 const struct pwm_state *state)
155{
156 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
157
158 if (state->polarity != pwm->state.polarity)
159 hibvt_pwm_set_polarity(chip, pwm, state->polarity);
160
161 if (state->period != pwm->state.period ||
162 state->duty_cycle != pwm->state.duty_cycle) {
163 hibvt_pwm_config(chip, pwm, state->duty_cycle, state->period);
164
165 /*
166 * Some implementations require the PWM to be enabled twice
167 * each time the duty cycle is refreshed.
168 */
169 if (hi_pwm_chip->soc->quirk_force_enable && state->enabled)
170 hibvt_pwm_enable(chip, pwm);
171 }
172
173 if (state->enabled != pwm->state.enabled) {
174 if (state->enabled)
175 hibvt_pwm_enable(chip, pwm);
176 else
177 hibvt_pwm_disable(chip, pwm);
178 }
179
180 return 0;
181}
182
183static const struct pwm_ops hibvt_pwm_ops = {
184 .get_state = hibvt_pwm_get_state,
185 .apply = hibvt_pwm_apply,
186
187};
188
189static int hibvt_pwm_probe(struct platform_device *pdev)
190{
191 const struct hibvt_pwm_soc *soc =
192 of_device_get_match_data(&pdev->dev);
193 struct pwm_chip *chip;
194 struct hibvt_pwm_chip *hi_pwm_chip;
195 int ret, i;
196
197 chip = devm_pwmchip_alloc(&pdev->dev, soc->num_pwms, sizeof(*hi_pwm_chip));
198 if (IS_ERR(chip))
199 return PTR_ERR(chip);
200 hi_pwm_chip = to_hibvt_pwm_chip(chip);
201
202 hi_pwm_chip->clk = devm_clk_get(&pdev->dev, NULL);
203 if (IS_ERR(hi_pwm_chip->clk)) {
204 dev_err(&pdev->dev, "getting clock failed with %ld\n",
205 PTR_ERR(hi_pwm_chip->clk));
206 return PTR_ERR(hi_pwm_chip->clk);
207 }
208
209 chip->ops = &hibvt_pwm_ops;
210 hi_pwm_chip->soc = soc;
211
212 hi_pwm_chip->base = devm_platform_ioremap_resource(pdev, 0);
213 if (IS_ERR(hi_pwm_chip->base))
214 return PTR_ERR(hi_pwm_chip->base);
215
216 ret = clk_prepare_enable(hi_pwm_chip->clk);
217 if (ret < 0)
218 return ret;
219
220 hi_pwm_chip->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
221 if (IS_ERR(hi_pwm_chip->rstc)) {
222 clk_disable_unprepare(hi_pwm_chip->clk);
223 return PTR_ERR(hi_pwm_chip->rstc);
224 }
225
226 reset_control_assert(hi_pwm_chip->rstc);
227 msleep(30);
228 reset_control_deassert(hi_pwm_chip->rstc);
229
230 ret = pwmchip_add(chip);
231 if (ret < 0) {
232 clk_disable_unprepare(hi_pwm_chip->clk);
233 return ret;
234 }
235
236 for (i = 0; i < chip->npwm; i++) {
237 hibvt_pwm_set_bits(hi_pwm_chip->base, PWM_CTRL_ADDR(i),
238 PWM_KEEP_MASK, (0x1 << PWM_KEEP_SHIFT));
239 }
240
241 platform_set_drvdata(pdev, chip);
242
243 return 0;
244}
245
246static void hibvt_pwm_remove(struct platform_device *pdev)
247{
248 struct pwm_chip *chip = platform_get_drvdata(pdev);
249 struct hibvt_pwm_chip *hi_pwm_chip = to_hibvt_pwm_chip(chip);
250
251 pwmchip_remove(chip);
252
253 reset_control_assert(hi_pwm_chip->rstc);
254 msleep(30);
255 reset_control_deassert(hi_pwm_chip->rstc);
256
257 clk_disable_unprepare(hi_pwm_chip->clk);
258}
259
260static const struct of_device_id hibvt_pwm_of_match[] = {
261 { .compatible = "hisilicon,hi3516cv300-pwm",
262 .data = &hi3516cv300_soc_info },
263 { .compatible = "hisilicon,hi3519v100-pwm",
264 .data = &hi3519v100_soc_info },
265 { .compatible = "hisilicon,hi3559v100-shub-pwm",
266 .data = &hi3559v100_shub_soc_info },
267 { .compatible = "hisilicon,hi3559v100-pwm",
268 .data = &hi3559v100_soc_info },
269 { }
270};
271MODULE_DEVICE_TABLE(of, hibvt_pwm_of_match);
272
273static struct platform_driver hibvt_pwm_driver = {
274 .driver = {
275 .name = "hibvt-pwm",
276 .of_match_table = hibvt_pwm_of_match,
277 },
278 .probe = hibvt_pwm_probe,
279 .remove = hibvt_pwm_remove,
280};
281module_platform_driver(hibvt_pwm_driver);
282
283MODULE_AUTHOR("Jian Yuan");
284MODULE_DESCRIPTION("HiSilicon BVT SoCs PWM driver");
285MODULE_LICENSE("GPL");