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1/*
2 * Copyright (C) 2014 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
7 *
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/clk.h>
15#include <linux/delay.h>
16#include <linux/err.h>
17#include <linux/io.h>
18#include <linux/ioport.h>
19#include <linux/math64.h>
20#include <linux/module.h>
21#include <linux/of.h>
22#include <linux/platform_device.h>
23#include <linux/pwm.h>
24#include <linux/slab.h>
25#include <linux/types.h>
26
27/*
28 * The Kona PWM has some unusual characteristics. Here are the main points.
29 *
30 * 1) There is no disable bit and the hardware docs advise programming a zero
31 * duty to achieve output equivalent to that of a normal disable operation.
32 *
33 * 2) Changes to prescale, duty, period, and polarity do not take effect until
34 * a subsequent rising edge of the trigger bit.
35 *
36 * 3) If the smooth bit and trigger bit are both low, the output is a constant
37 * high signal. Otherwise, the earlier waveform continues to be output.
38 *
39 * 4) If the smooth bit is set on the rising edge of the trigger bit, output
40 * will transition to the new settings on a period boundary (which could be
41 * seconds away). If the smooth bit is clear, new settings will be applied
42 * as soon as possible (the hardware always has a 400ns delay).
43 *
44 * 5) When the external clock that feeds the PWM is disabled, output is pegged
45 * high or low depending on its state at that exact instant.
46 */
47
48#define PWM_CONTROL_OFFSET (0x00000000)
49#define PWM_CONTROL_SMOOTH_SHIFT(chan) (24 + (chan))
50#define PWM_CONTROL_TYPE_SHIFT(chan) (16 + (chan))
51#define PWM_CONTROL_POLARITY_SHIFT(chan) (8 + (chan))
52#define PWM_CONTROL_TRIGGER_SHIFT(chan) (chan)
53
54#define PRESCALE_OFFSET (0x00000004)
55#define PRESCALE_SHIFT(chan) ((chan) << 2)
56#define PRESCALE_MASK(chan) (0x7 << PRESCALE_SHIFT(chan))
57#define PRESCALE_MIN (0x00000000)
58#define PRESCALE_MAX (0x00000007)
59
60#define PERIOD_COUNT_OFFSET(chan) (0x00000008 + ((chan) << 3))
61#define PERIOD_COUNT_MIN (0x00000002)
62#define PERIOD_COUNT_MAX (0x00ffffff)
63
64#define DUTY_CYCLE_HIGH_OFFSET(chan) (0x0000000c + ((chan) << 3))
65#define DUTY_CYCLE_HIGH_MIN (0x00000000)
66#define DUTY_CYCLE_HIGH_MAX (0x00ffffff)
67
68struct kona_pwmc {
69 struct pwm_chip chip;
70 void __iomem *base;
71 struct clk *clk;
72};
73
74static inline struct kona_pwmc *to_kona_pwmc(struct pwm_chip *_chip)
75{
76 return container_of(_chip, struct kona_pwmc, chip);
77}
78
79/*
80 * Clear trigger bit but set smooth bit to maintain old output.
81 */
82static void kona_pwmc_prepare_for_settings(struct kona_pwmc *kp,
83 unsigned int chan)
84{
85 unsigned int value = readl(kp->base + PWM_CONTROL_OFFSET);
86
87 value |= 1 << PWM_CONTROL_SMOOTH_SHIFT(chan);
88 value &= ~(1 << PWM_CONTROL_TRIGGER_SHIFT(chan));
89 writel(value, kp->base + PWM_CONTROL_OFFSET);
90
91 /*
92 * There must be a min 400ns delay between clearing trigger and setting
93 * it. Failing to do this may result in no PWM signal.
94 */
95 ndelay(400);
96}
97
98static void kona_pwmc_apply_settings(struct kona_pwmc *kp, unsigned int chan)
99{
100 unsigned int value = readl(kp->base + PWM_CONTROL_OFFSET);
101
102 /* Set trigger bit and clear smooth bit to apply new settings */
103 value &= ~(1 << PWM_CONTROL_SMOOTH_SHIFT(chan));
104 value |= 1 << PWM_CONTROL_TRIGGER_SHIFT(chan);
105 writel(value, kp->base + PWM_CONTROL_OFFSET);
106
107 /* Trigger bit must be held high for at least 400 ns. */
108 ndelay(400);
109}
110
111static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm,
112 int duty_ns, int period_ns)
113{
114 struct kona_pwmc *kp = to_kona_pwmc(chip);
115 u64 val, div, rate;
116 unsigned long prescale = PRESCALE_MIN, pc, dc;
117 unsigned int value, chan = pwm->hwpwm;
118
119 /*
120 * Find period count, duty count and prescale to suit duty_ns and
121 * period_ns. This is done according to formulas described below:
122 *
123 * period_ns = 10^9 * (PRESCALE + 1) * PC / PWM_CLK_RATE
124 * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
125 *
126 * PC = (PWM_CLK_RATE * period_ns) / (10^9 * (PRESCALE + 1))
127 * DC = (PWM_CLK_RATE * duty_ns) / (10^9 * (PRESCALE + 1))
128 */
129
130 rate = clk_get_rate(kp->clk);
131
132 while (1) {
133 div = 1000000000;
134 div *= 1 + prescale;
135 val = rate * period_ns;
136 pc = div64_u64(val, div);
137 val = rate * duty_ns;
138 dc = div64_u64(val, div);
139
140 /* If duty_ns or period_ns are not achievable then return */
141 if (pc < PERIOD_COUNT_MIN || dc < DUTY_CYCLE_HIGH_MIN)
142 return -EINVAL;
143
144 /* If pc and dc are in bounds, the calculation is done */
145 if (pc <= PERIOD_COUNT_MAX && dc <= DUTY_CYCLE_HIGH_MAX)
146 break;
147
148 /* Otherwise, increase prescale and recalculate pc and dc */
149 if (++prescale > PRESCALE_MAX)
150 return -EINVAL;
151 }
152
153 /*
154 * Don't apply settings if disabled. The period and duty cycle are
155 * always calculated above to ensure the new values are
156 * validated immediately instead of on enable.
157 */
158 if (pwm_is_enabled(pwm)) {
159 kona_pwmc_prepare_for_settings(kp, chan);
160
161 value = readl(kp->base + PRESCALE_OFFSET);
162 value &= ~PRESCALE_MASK(chan);
163 value |= prescale << PRESCALE_SHIFT(chan);
164 writel(value, kp->base + PRESCALE_OFFSET);
165
166 writel(pc, kp->base + PERIOD_COUNT_OFFSET(chan));
167
168 writel(dc, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan));
169
170 kona_pwmc_apply_settings(kp, chan);
171 }
172
173 return 0;
174}
175
176static int kona_pwmc_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
177 enum pwm_polarity polarity)
178{
179 struct kona_pwmc *kp = to_kona_pwmc(chip);
180 unsigned int chan = pwm->hwpwm;
181 unsigned int value;
182 int ret;
183
184 ret = clk_prepare_enable(kp->clk);
185 if (ret < 0) {
186 dev_err(chip->dev, "failed to enable clock: %d\n", ret);
187 return ret;
188 }
189
190 kona_pwmc_prepare_for_settings(kp, chan);
191
192 value = readl(kp->base + PWM_CONTROL_OFFSET);
193
194 if (polarity == PWM_POLARITY_NORMAL)
195 value |= 1 << PWM_CONTROL_POLARITY_SHIFT(chan);
196 else
197 value &= ~(1 << PWM_CONTROL_POLARITY_SHIFT(chan));
198
199 writel(value, kp->base + PWM_CONTROL_OFFSET);
200
201 kona_pwmc_apply_settings(kp, chan);
202
203 clk_disable_unprepare(kp->clk);
204
205 return 0;
206}
207
208static int kona_pwmc_enable(struct pwm_chip *chip, struct pwm_device *pwm)
209{
210 struct kona_pwmc *kp = to_kona_pwmc(chip);
211 int ret;
212
213 ret = clk_prepare_enable(kp->clk);
214 if (ret < 0) {
215 dev_err(chip->dev, "failed to enable clock: %d\n", ret);
216 return ret;
217 }
218
219 ret = kona_pwmc_config(chip, pwm, pwm_get_duty_cycle(pwm),
220 pwm_get_period(pwm));
221 if (ret < 0) {
222 clk_disable_unprepare(kp->clk);
223 return ret;
224 }
225
226 return 0;
227}
228
229static void kona_pwmc_disable(struct pwm_chip *chip, struct pwm_device *pwm)
230{
231 struct kona_pwmc *kp = to_kona_pwmc(chip);
232 unsigned int chan = pwm->hwpwm;
233 unsigned int value;
234
235 kona_pwmc_prepare_for_settings(kp, chan);
236
237 /* Simulate a disable by configuring for zero duty */
238 writel(0, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan));
239 writel(0, kp->base + PERIOD_COUNT_OFFSET(chan));
240
241 /* Set prescale to 0 for this channel */
242 value = readl(kp->base + PRESCALE_OFFSET);
243 value &= ~PRESCALE_MASK(chan);
244 writel(value, kp->base + PRESCALE_OFFSET);
245
246 kona_pwmc_apply_settings(kp, chan);
247
248 clk_disable_unprepare(kp->clk);
249}
250
251static const struct pwm_ops kona_pwm_ops = {
252 .config = kona_pwmc_config,
253 .set_polarity = kona_pwmc_set_polarity,
254 .enable = kona_pwmc_enable,
255 .disable = kona_pwmc_disable,
256 .owner = THIS_MODULE,
257};
258
259static int kona_pwmc_probe(struct platform_device *pdev)
260{
261 struct kona_pwmc *kp;
262 struct resource *res;
263 unsigned int chan;
264 unsigned int value = 0;
265 int ret = 0;
266
267 kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL);
268 if (kp == NULL)
269 return -ENOMEM;
270
271 platform_set_drvdata(pdev, kp);
272
273 kp->chip.dev = &pdev->dev;
274 kp->chip.ops = &kona_pwm_ops;
275 kp->chip.base = -1;
276 kp->chip.npwm = 6;
277 kp->chip.of_xlate = of_pwm_xlate_with_flags;
278 kp->chip.of_pwm_n_cells = 3;
279 kp->chip.can_sleep = true;
280
281 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
282 kp->base = devm_ioremap_resource(&pdev->dev, res);
283 if (IS_ERR(kp->base))
284 return PTR_ERR(kp->base);
285
286 kp->clk = devm_clk_get(&pdev->dev, NULL);
287 if (IS_ERR(kp->clk)) {
288 dev_err(&pdev->dev, "failed to get clock: %ld\n",
289 PTR_ERR(kp->clk));
290 return PTR_ERR(kp->clk);
291 }
292
293 ret = clk_prepare_enable(kp->clk);
294 if (ret < 0) {
295 dev_err(&pdev->dev, "failed to enable clock: %d\n", ret);
296 return ret;
297 }
298
299 /* Set push/pull for all channels */
300 for (chan = 0; chan < kp->chip.npwm; chan++)
301 value |= (1 << PWM_CONTROL_TYPE_SHIFT(chan));
302
303 writel(value, kp->base + PWM_CONTROL_OFFSET);
304
305 clk_disable_unprepare(kp->clk);
306
307 ret = pwmchip_add_with_polarity(&kp->chip, PWM_POLARITY_INVERSED);
308 if (ret < 0)
309 dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
310
311 return ret;
312}
313
314static int kona_pwmc_remove(struct platform_device *pdev)
315{
316 struct kona_pwmc *kp = platform_get_drvdata(pdev);
317 unsigned int chan;
318
319 for (chan = 0; chan < kp->chip.npwm; chan++)
320 if (pwm_is_enabled(&kp->chip.pwms[chan]))
321 clk_disable_unprepare(kp->clk);
322
323 return pwmchip_remove(&kp->chip);
324}
325
326static const struct of_device_id bcm_kona_pwmc_dt[] = {
327 { .compatible = "brcm,kona-pwm" },
328 { },
329};
330MODULE_DEVICE_TABLE(of, bcm_kona_pwmc_dt);
331
332static struct platform_driver kona_pwmc_driver = {
333 .driver = {
334 .name = "bcm-kona-pwm",
335 .of_match_table = bcm_kona_pwmc_dt,
336 },
337 .probe = kona_pwmc_probe,
338 .remove = kona_pwmc_remove,
339};
340module_platform_driver(kona_pwmc_driver);
341
342MODULE_AUTHOR("Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>");
343MODULE_AUTHOR("Tim Kryger <tkryger@broadcom.com>");
344MODULE_DESCRIPTION("Broadcom Kona PWM driver");
345MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0-only
2// Copyright (C) 2014 Broadcom Corporation
3
4#include <linux/clk.h>
5#include <linux/delay.h>
6#include <linux/err.h>
7#include <linux/io.h>
8#include <linux/ioport.h>
9#include <linux/math64.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/platform_device.h>
13#include <linux/pwm.h>
14#include <linux/slab.h>
15#include <linux/types.h>
16
17/*
18 * The Kona PWM has some unusual characteristics. Here are the main points.
19 *
20 * 1) There is no disable bit and the hardware docs advise programming a zero
21 * duty to achieve output equivalent to that of a normal disable operation.
22 *
23 * 2) Changes to prescale, duty, period, and polarity do not take effect until
24 * a subsequent rising edge of the trigger bit.
25 *
26 * 3) If the smooth bit and trigger bit are both low, the output is a constant
27 * high signal. Otherwise, the earlier waveform continues to be output.
28 *
29 * 4) If the smooth bit is set on the rising edge of the trigger bit, output
30 * will transition to the new settings on a period boundary (which could be
31 * seconds away). If the smooth bit is clear, new settings will be applied
32 * as soon as possible (the hardware always has a 400ns delay).
33 *
34 * 5) When the external clock that feeds the PWM is disabled, output is pegged
35 * high or low depending on its state at that exact instant.
36 */
37
38#define PWM_CONTROL_OFFSET 0x00000000
39#define PWM_CONTROL_SMOOTH_SHIFT(chan) (24 + (chan))
40#define PWM_CONTROL_TYPE_SHIFT(chan) (16 + (chan))
41#define PWM_CONTROL_POLARITY_SHIFT(chan) (8 + (chan))
42#define PWM_CONTROL_TRIGGER_SHIFT(chan) (chan)
43
44#define PRESCALE_OFFSET 0x00000004
45#define PRESCALE_SHIFT(chan) ((chan) << 2)
46#define PRESCALE_MASK(chan) (0x7 << PRESCALE_SHIFT(chan))
47#define PRESCALE_MIN 0x00000000
48#define PRESCALE_MAX 0x00000007
49
50#define PERIOD_COUNT_OFFSET(chan) (0x00000008 + ((chan) << 3))
51#define PERIOD_COUNT_MIN 0x00000002
52#define PERIOD_COUNT_MAX 0x00ffffff
53
54#define DUTY_CYCLE_HIGH_OFFSET(chan) (0x0000000c + ((chan) << 3))
55#define DUTY_CYCLE_HIGH_MIN 0x00000000
56#define DUTY_CYCLE_HIGH_MAX 0x00ffffff
57
58struct kona_pwmc {
59 void __iomem *base;
60 struct clk *clk;
61};
62
63static inline struct kona_pwmc *to_kona_pwmc(struct pwm_chip *chip)
64{
65 return pwmchip_get_drvdata(chip);
66}
67
68/*
69 * Clear trigger bit but set smooth bit to maintain old output.
70 */
71static void kona_pwmc_prepare_for_settings(struct kona_pwmc *kp,
72 unsigned int chan)
73{
74 unsigned int value = readl(kp->base + PWM_CONTROL_OFFSET);
75
76 value |= 1 << PWM_CONTROL_SMOOTH_SHIFT(chan);
77 value &= ~(1 << PWM_CONTROL_TRIGGER_SHIFT(chan));
78 writel(value, kp->base + PWM_CONTROL_OFFSET);
79
80 /*
81 * There must be a min 400ns delay between clearing trigger and setting
82 * it. Failing to do this may result in no PWM signal.
83 */
84 ndelay(400);
85}
86
87static void kona_pwmc_apply_settings(struct kona_pwmc *kp, unsigned int chan)
88{
89 unsigned int value = readl(kp->base + PWM_CONTROL_OFFSET);
90
91 /* Set trigger bit and clear smooth bit to apply new settings */
92 value &= ~(1 << PWM_CONTROL_SMOOTH_SHIFT(chan));
93 value |= 1 << PWM_CONTROL_TRIGGER_SHIFT(chan);
94 writel(value, kp->base + PWM_CONTROL_OFFSET);
95
96 /* Trigger bit must be held high for at least 400 ns. */
97 ndelay(400);
98}
99
100static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm,
101 u64 duty_ns, u64 period_ns)
102{
103 struct kona_pwmc *kp = to_kona_pwmc(chip);
104 u64 div, rate;
105 unsigned long prescale = PRESCALE_MIN, pc, dc;
106 unsigned int value, chan = pwm->hwpwm;
107
108 /*
109 * Find period count, duty count and prescale to suit duty_ns and
110 * period_ns. This is done according to formulas described below:
111 *
112 * period_ns = 10^9 * (PRESCALE + 1) * PC / PWM_CLK_RATE
113 * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
114 *
115 * PC = (PWM_CLK_RATE * period_ns) / (10^9 * (PRESCALE + 1))
116 * DC = (PWM_CLK_RATE * duty_ns) / (10^9 * (PRESCALE + 1))
117 */
118
119 rate = clk_get_rate(kp->clk);
120
121 while (1) {
122 div = 1000000000;
123 div *= 1 + prescale;
124 pc = mul_u64_u64_div_u64(rate, period_ns, div);
125 dc = mul_u64_u64_div_u64(rate, duty_ns, div);
126
127 /* If duty_ns or period_ns are not achievable then return */
128 if (pc < PERIOD_COUNT_MIN)
129 return -EINVAL;
130
131 /* If pc and dc are in bounds, the calculation is done */
132 if (pc <= PERIOD_COUNT_MAX && dc <= DUTY_CYCLE_HIGH_MAX)
133 break;
134
135 /* Otherwise, increase prescale and recalculate pc and dc */
136 if (++prescale > PRESCALE_MAX)
137 return -EINVAL;
138 }
139
140 kona_pwmc_prepare_for_settings(kp, chan);
141
142 value = readl(kp->base + PRESCALE_OFFSET);
143 value &= ~PRESCALE_MASK(chan);
144 value |= prescale << PRESCALE_SHIFT(chan);
145 writel(value, kp->base + PRESCALE_OFFSET);
146
147 writel(pc, kp->base + PERIOD_COUNT_OFFSET(chan));
148
149 writel(dc, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan));
150
151 kona_pwmc_apply_settings(kp, chan);
152
153 return 0;
154}
155
156static int kona_pwmc_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
157 enum pwm_polarity polarity)
158{
159 struct kona_pwmc *kp = to_kona_pwmc(chip);
160 unsigned int chan = pwm->hwpwm;
161 unsigned int value;
162 int ret;
163
164 ret = clk_prepare_enable(kp->clk);
165 if (ret < 0) {
166 dev_err(pwmchip_parent(chip), "failed to enable clock: %d\n", ret);
167 return ret;
168 }
169
170 kona_pwmc_prepare_for_settings(kp, chan);
171
172 value = readl(kp->base + PWM_CONTROL_OFFSET);
173
174 if (polarity == PWM_POLARITY_NORMAL)
175 value |= 1 << PWM_CONTROL_POLARITY_SHIFT(chan);
176 else
177 value &= ~(1 << PWM_CONTROL_POLARITY_SHIFT(chan));
178
179 writel(value, kp->base + PWM_CONTROL_OFFSET);
180
181 kona_pwmc_apply_settings(kp, chan);
182
183 clk_disable_unprepare(kp->clk);
184
185 return 0;
186}
187
188static int kona_pwmc_enable(struct pwm_chip *chip, struct pwm_device *pwm)
189{
190 struct kona_pwmc *kp = to_kona_pwmc(chip);
191 int ret;
192
193 ret = clk_prepare_enable(kp->clk);
194 if (ret < 0) {
195 dev_err(pwmchip_parent(chip), "failed to enable clock: %d\n", ret);
196 return ret;
197 }
198
199 return 0;
200}
201
202static void kona_pwmc_disable(struct pwm_chip *chip, struct pwm_device *pwm)
203{
204 struct kona_pwmc *kp = to_kona_pwmc(chip);
205 unsigned int chan = pwm->hwpwm;
206 unsigned int value;
207
208 kona_pwmc_prepare_for_settings(kp, chan);
209
210 /* Simulate a disable by configuring for zero duty */
211 writel(0, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan));
212 writel(0, kp->base + PERIOD_COUNT_OFFSET(chan));
213
214 /* Set prescale to 0 for this channel */
215 value = readl(kp->base + PRESCALE_OFFSET);
216 value &= ~PRESCALE_MASK(chan);
217 writel(value, kp->base + PRESCALE_OFFSET);
218
219 kona_pwmc_apply_settings(kp, chan);
220
221 clk_disable_unprepare(kp->clk);
222}
223
224static int kona_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm,
225 const struct pwm_state *state)
226{
227 int err;
228 struct kona_pwmc *kp = to_kona_pwmc(chip);
229 bool enabled = pwm->state.enabled;
230
231 if (state->polarity != pwm->state.polarity) {
232 if (enabled) {
233 kona_pwmc_disable(chip, pwm);
234 enabled = false;
235 }
236
237 err = kona_pwmc_set_polarity(chip, pwm, state->polarity);
238 if (err)
239 return err;
240
241 pwm->state.polarity = state->polarity;
242 }
243
244 if (!state->enabled) {
245 if (enabled)
246 kona_pwmc_disable(chip, pwm);
247 return 0;
248 } else if (!enabled) {
249 /*
250 * This is a bit special here, usually the PWM should only be
251 * enabled when duty and period are setup. But before this
252 * driver was converted to .apply it was done the other way
253 * around and so this behaviour was kept even though this might
254 * result in a glitch. This might be improvable by someone with
255 * hardware and/or documentation.
256 */
257 err = kona_pwmc_enable(chip, pwm);
258 if (err)
259 return err;
260 }
261
262 err = kona_pwmc_config(chip, pwm, state->duty_cycle, state->period);
263 if (err && !pwm->state.enabled)
264 clk_disable_unprepare(kp->clk);
265
266 return err;
267}
268
269static const struct pwm_ops kona_pwm_ops = {
270 .apply = kona_pwmc_apply,
271};
272
273static int kona_pwmc_probe(struct platform_device *pdev)
274{
275 struct pwm_chip *chip;
276 struct kona_pwmc *kp;
277 unsigned int chan;
278 unsigned int value = 0;
279 int ret = 0;
280
281 chip = devm_pwmchip_alloc(&pdev->dev, 6, sizeof(*kp));
282 if (IS_ERR(chip))
283 return PTR_ERR(chip);
284 kp = to_kona_pwmc(chip);
285
286 chip->ops = &kona_pwm_ops;
287
288 kp->base = devm_platform_ioremap_resource(pdev, 0);
289 if (IS_ERR(kp->base))
290 return PTR_ERR(kp->base);
291
292 kp->clk = devm_clk_get(&pdev->dev, NULL);
293 if (IS_ERR(kp->clk)) {
294 dev_err(&pdev->dev, "failed to get clock: %ld\n",
295 PTR_ERR(kp->clk));
296 return PTR_ERR(kp->clk);
297 }
298
299 ret = clk_prepare_enable(kp->clk);
300 if (ret < 0) {
301 dev_err(&pdev->dev, "failed to enable clock: %d\n", ret);
302 return ret;
303 }
304
305 /* Set push/pull for all channels */
306 for (chan = 0; chan < chip->npwm; chan++)
307 value |= (1 << PWM_CONTROL_TYPE_SHIFT(chan));
308
309 writel(value, kp->base + PWM_CONTROL_OFFSET);
310
311 clk_disable_unprepare(kp->clk);
312
313 ret = devm_pwmchip_add(&pdev->dev, chip);
314 if (ret < 0)
315 dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
316
317 return ret;
318}
319
320static const struct of_device_id bcm_kona_pwmc_dt[] = {
321 { .compatible = "brcm,kona-pwm" },
322 { },
323};
324MODULE_DEVICE_TABLE(of, bcm_kona_pwmc_dt);
325
326static struct platform_driver kona_pwmc_driver = {
327 .driver = {
328 .name = "bcm-kona-pwm",
329 .of_match_table = bcm_kona_pwmc_dt,
330 },
331 .probe = kona_pwmc_probe,
332};
333module_platform_driver(kona_pwmc_driver);
334
335MODULE_AUTHOR("Broadcom Corporation <bcm-kernel-feedback-list@broadcom.com>");
336MODULE_AUTHOR("Tim Kryger <tkryger@broadcom.com>");
337MODULE_DESCRIPTION("Broadcom Kona PWM driver");
338MODULE_LICENSE("GPL v2");