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