Commit | Line | Data |
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101353c8 BG |
1 | /* |
2 | * PWM driver for Rockchip SoCs | |
3 | * | |
4 | * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> | |
f6306299 | 5 | * Copyright (C) 2014 ROCKCHIP, Inc. |
101353c8 BG |
6 | * |
7 | * This program is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU General Public License | |
9 | * version 2 as published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/clk.h> | |
13 | #include <linux/io.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/of.h> | |
f6306299 | 16 | #include <linux/of_device.h> |
101353c8 BG |
17 | #include <linux/platform_device.h> |
18 | #include <linux/pwm.h> | |
19 | #include <linux/time.h> | |
20 | ||
101353c8 BG |
21 | #define PWM_CTRL_TIMER_EN (1 << 0) |
22 | #define PWM_CTRL_OUTPUT_EN (1 << 3) | |
23 | ||
f6306299 CW |
24 | #define PWM_ENABLE (1 << 0) |
25 | #define PWM_CONTINUOUS (1 << 1) | |
26 | #define PWM_DUTY_POSITIVE (1 << 3) | |
7264354c | 27 | #define PWM_DUTY_NEGATIVE (0 << 3) |
f6306299 | 28 | #define PWM_INACTIVE_NEGATIVE (0 << 4) |
7264354c | 29 | #define PWM_INACTIVE_POSITIVE (1 << 4) |
f6306299 CW |
30 | #define PWM_OUTPUT_LEFT (0 << 5) |
31 | #define PWM_LP_DISABLE (0 << 8) | |
101353c8 BG |
32 | |
33 | struct rockchip_pwm_chip { | |
34 | struct pwm_chip chip; | |
35 | struct clk *clk; | |
f6306299 | 36 | const struct rockchip_pwm_data *data; |
101353c8 BG |
37 | void __iomem *base; |
38 | }; | |
39 | ||
f6306299 CW |
40 | struct rockchip_pwm_regs { |
41 | unsigned long duty; | |
42 | unsigned long period; | |
43 | unsigned long cntr; | |
44 | unsigned long ctrl; | |
45 | }; | |
46 | ||
47 | struct rockchip_pwm_data { | |
48 | struct rockchip_pwm_regs regs; | |
49 | unsigned int prescaler; | |
7264354c | 50 | const struct pwm_ops *ops; |
f6306299 | 51 | |
7264354c DA |
52 | void (*set_enable)(struct pwm_chip *chip, |
53 | struct pwm_device *pwm, bool enable); | |
f6306299 CW |
54 | }; |
55 | ||
101353c8 BG |
56 | static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c) |
57 | { | |
58 | return container_of(c, struct rockchip_pwm_chip, chip); | |
59 | } | |
60 | ||
7264354c DA |
61 | static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip, |
62 | struct pwm_device *pwm, bool enable) | |
f6306299 CW |
63 | { |
64 | struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); | |
65 | u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN; | |
66 | u32 val; | |
67 | ||
68 | val = readl_relaxed(pc->base + pc->data->regs.ctrl); | |
69 | ||
70 | if (enable) | |
71 | val |= enable_conf; | |
72 | else | |
73 | val &= ~enable_conf; | |
74 | ||
75 | writel_relaxed(val, pc->base + pc->data->regs.ctrl); | |
76 | } | |
77 | ||
7264354c DA |
78 | static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, |
79 | struct pwm_device *pwm, bool enable) | |
f6306299 CW |
80 | { |
81 | struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); | |
82 | u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE | | |
7264354c | 83 | PWM_CONTINUOUS; |
f6306299 CW |
84 | u32 val; |
85 | ||
7264354c DA |
86 | if (pwm->polarity == PWM_POLARITY_INVERSED) |
87 | enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE; | |
88 | else | |
89 | enable_conf |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE; | |
90 | ||
f6306299 CW |
91 | val = readl_relaxed(pc->base + pc->data->regs.ctrl); |
92 | ||
93 | if (enable) | |
94 | val |= enable_conf; | |
95 | else | |
96 | val &= ~enable_conf; | |
97 | ||
98 | writel_relaxed(val, pc->base + pc->data->regs.ctrl); | |
99 | } | |
100 | ||
101353c8 BG |
101 | static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, |
102 | int duty_ns, int period_ns) | |
103 | { | |
104 | struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); | |
105 | unsigned long period, duty; | |
106 | u64 clk_rate, div; | |
107 | int ret; | |
108 | ||
109 | clk_rate = clk_get_rate(pc->clk); | |
110 | ||
111 | /* | |
112 | * Since period and duty cycle registers have a width of 32 | |
113 | * bits, every possible input period can be obtained using the | |
114 | * default prescaler value for all practical clock rate values. | |
115 | */ | |
116 | div = clk_rate * period_ns; | |
f6306299 | 117 | do_div(div, pc->data->prescaler * NSEC_PER_SEC); |
101353c8 BG |
118 | period = div; |
119 | ||
120 | div = clk_rate * duty_ns; | |
f6306299 | 121 | do_div(div, pc->data->prescaler * NSEC_PER_SEC); |
101353c8 BG |
122 | duty = div; |
123 | ||
124 | ret = clk_enable(pc->clk); | |
125 | if (ret) | |
126 | return ret; | |
127 | ||
f6306299 CW |
128 | writel(period, pc->base + pc->data->regs.period); |
129 | writel(duty, pc->base + pc->data->regs.duty); | |
130 | writel(0, pc->base + pc->data->regs.cntr); | |
101353c8 BG |
131 | |
132 | clk_disable(pc->clk); | |
133 | ||
134 | return 0; | |
135 | } | |
136 | ||
7264354c DA |
137 | static int rockchip_pwm_set_polarity(struct pwm_chip *chip, |
138 | struct pwm_device *pwm, | |
139 | enum pwm_polarity polarity) | |
140 | { | |
141 | /* | |
142 | * No action needed here because pwm->polarity will be set by the core | |
143 | * and the core will only change polarity when the PWM is not enabled. | |
144 | * We'll handle things in set_enable(). | |
145 | */ | |
146 | ||
147 | return 0; | |
148 | } | |
149 | ||
101353c8 BG |
150 | static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) |
151 | { | |
152 | struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); | |
153 | int ret; | |
101353c8 BG |
154 | |
155 | ret = clk_enable(pc->clk); | |
156 | if (ret) | |
157 | return ret; | |
158 | ||
7264354c | 159 | pc->data->set_enable(chip, pwm, true); |
101353c8 BG |
160 | |
161 | return 0; | |
162 | } | |
163 | ||
164 | static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) | |
165 | { | |
166 | struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); | |
101353c8 | 167 | |
7264354c | 168 | pc->data->set_enable(chip, pwm, false); |
101353c8 BG |
169 | |
170 | clk_disable(pc->clk); | |
171 | } | |
172 | ||
7264354c | 173 | static const struct pwm_ops rockchip_pwm_ops_v1 = { |
101353c8 BG |
174 | .config = rockchip_pwm_config, |
175 | .enable = rockchip_pwm_enable, | |
176 | .disable = rockchip_pwm_disable, | |
177 | .owner = THIS_MODULE, | |
178 | }; | |
179 | ||
7264354c DA |
180 | static const struct pwm_ops rockchip_pwm_ops_v2 = { |
181 | .config = rockchip_pwm_config, | |
182 | .set_polarity = rockchip_pwm_set_polarity, | |
183 | .enable = rockchip_pwm_enable, | |
184 | .disable = rockchip_pwm_disable, | |
185 | .owner = THIS_MODULE, | |
186 | }; | |
187 | ||
f6306299 CW |
188 | static const struct rockchip_pwm_data pwm_data_v1 = { |
189 | .regs = { | |
190 | .duty = 0x04, | |
191 | .period = 0x08, | |
192 | .cntr = 0x00, | |
193 | .ctrl = 0x0c, | |
194 | }, | |
195 | .prescaler = 2, | |
7264354c | 196 | .ops = &rockchip_pwm_ops_v1, |
f6306299 CW |
197 | .set_enable = rockchip_pwm_set_enable_v1, |
198 | }; | |
199 | ||
200 | static const struct rockchip_pwm_data pwm_data_v2 = { | |
201 | .regs = { | |
202 | .duty = 0x08, | |
203 | .period = 0x04, | |
204 | .cntr = 0x00, | |
205 | .ctrl = 0x0c, | |
206 | }, | |
207 | .prescaler = 1, | |
7264354c | 208 | .ops = &rockchip_pwm_ops_v2, |
f6306299 CW |
209 | .set_enable = rockchip_pwm_set_enable_v2, |
210 | }; | |
211 | ||
212 | static const struct rockchip_pwm_data pwm_data_vop = { | |
213 | .regs = { | |
214 | .duty = 0x08, | |
215 | .period = 0x04, | |
216 | .cntr = 0x0c, | |
217 | .ctrl = 0x00, | |
218 | }, | |
219 | .prescaler = 1, | |
7264354c | 220 | .ops = &rockchip_pwm_ops_v2, |
f6306299 CW |
221 | .set_enable = rockchip_pwm_set_enable_v2, |
222 | }; | |
223 | ||
224 | static const struct of_device_id rockchip_pwm_dt_ids[] = { | |
225 | { .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1}, | |
226 | { .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2}, | |
227 | { .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop}, | |
228 | { /* sentinel */ } | |
229 | }; | |
230 | MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids); | |
231 | ||
101353c8 BG |
232 | static int rockchip_pwm_probe(struct platform_device *pdev) |
233 | { | |
f6306299 | 234 | const struct of_device_id *id; |
101353c8 BG |
235 | struct rockchip_pwm_chip *pc; |
236 | struct resource *r; | |
237 | int ret; | |
238 | ||
f6306299 CW |
239 | id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev); |
240 | if (!id) | |
241 | return -EINVAL; | |
242 | ||
101353c8 BG |
243 | pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); |
244 | if (!pc) | |
245 | return -ENOMEM; | |
246 | ||
247 | r = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
248 | pc->base = devm_ioremap_resource(&pdev->dev, r); | |
249 | if (IS_ERR(pc->base)) | |
250 | return PTR_ERR(pc->base); | |
251 | ||
252 | pc->clk = devm_clk_get(&pdev->dev, NULL); | |
253 | if (IS_ERR(pc->clk)) | |
254 | return PTR_ERR(pc->clk); | |
255 | ||
256 | ret = clk_prepare(pc->clk); | |
257 | if (ret) | |
258 | return ret; | |
259 | ||
260 | platform_set_drvdata(pdev, pc); | |
261 | ||
f6306299 | 262 | pc->data = id->data; |
101353c8 | 263 | pc->chip.dev = &pdev->dev; |
7264354c | 264 | pc->chip.ops = pc->data->ops; |
101353c8 BG |
265 | pc->chip.base = -1; |
266 | pc->chip.npwm = 1; | |
267 | ||
7264354c DA |
268 | if (pc->data->ops->set_polarity) { |
269 | pc->chip.of_xlate = of_pwm_xlate_with_flags; | |
270 | pc->chip.of_pwm_n_cells = 3; | |
271 | } | |
272 | ||
101353c8 BG |
273 | ret = pwmchip_add(&pc->chip); |
274 | if (ret < 0) { | |
275 | clk_unprepare(pc->clk); | |
276 | dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); | |
277 | } | |
278 | ||
279 | return ret; | |
280 | } | |
281 | ||
282 | static int rockchip_pwm_remove(struct platform_device *pdev) | |
283 | { | |
284 | struct rockchip_pwm_chip *pc = platform_get_drvdata(pdev); | |
285 | ||
286 | clk_unprepare(pc->clk); | |
287 | ||
288 | return pwmchip_remove(&pc->chip); | |
289 | } | |
290 | ||
101353c8 BG |
291 | static struct platform_driver rockchip_pwm_driver = { |
292 | .driver = { | |
293 | .name = "rockchip-pwm", | |
294 | .of_match_table = rockchip_pwm_dt_ids, | |
295 | }, | |
296 | .probe = rockchip_pwm_probe, | |
297 | .remove = rockchip_pwm_remove, | |
298 | }; | |
299 | module_platform_driver(rockchip_pwm_driver); | |
300 | ||
301 | MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); | |
302 | MODULE_DESCRIPTION("Rockchip SoC PWM driver"); | |
303 | MODULE_LICENSE("GPL v2"); |