1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (C) 2017-2018 SiFive
5  * Reference Manual : https://static.dev.sifive.com/FU540-C000-v1.0.pdf
8  * - When changing both duty cycle and period, we cannot prevent in
11  * - The hardware cannot generate a 100% duty cycle.
12  * - The hardware generates only inverted output.
65 	mutex_lock(&ddata->lock);  in pwm_sifive_request()
66 	ddata->user_count++;  in pwm_sifive_request()
67 	mutex_unlock(&ddata->lock);  in pwm_sifive_request()
76 	mutex_lock(&ddata->lock);  in pwm_sifive_free()
77 	ddata->user_count--;  in pwm_sifive_free()
78 	mutex_unlock(&ddata->lock);  in pwm_sifive_free()
95 	scale_pow = div64_ul(ddata->approx_period * (u64)rate, NSEC_PER_SEC);  in pwm_sifive_update_clock()
96 	scale = clamp(ilog2(scale_pow) - PWM_SIFIVE_CMPWIDTH, 0, 0xf);  in pwm_sifive_update_clock()
100 	writel(val, ddata->regs + PWM_SIFIVE_PWMCFG);  in pwm_sifive_update_clock()
104 	ddata->real_period = div64_ul(num, rate);  in pwm_sifive_update_clock()
105 	dev_dbg(ddata->chip.dev,  in pwm_sifive_update_clock()
106 		"New real_period = %u ns\n", ddata->real_period);  in pwm_sifive_update_clock()
115 	duty = readl(ddata->regs + PWM_SIFIVE_PWMCMP0 +  in pwm_sifive_get_state()
116 		     pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP);  in pwm_sifive_get_state()
118 	state->enabled = duty > 0;  in pwm_sifive_get_state()
120 	val = readl(ddata->regs + PWM_SIFIVE_PWMCFG);  in pwm_sifive_get_state()
122 		state->enabled = false;  in pwm_sifive_get_state()
124 	state->period = ddata->real_period;  in pwm_sifive_get_state()
125 	state->duty_cycle =  in pwm_sifive_get_state()
126 		(u64)duty * ddata->real_period >> PWM_SIFIVE_CMPWIDTH;  in pwm_sifive_get_state()
127 	state->polarity = PWM_POLARITY_INVERSED;  in pwm_sifive_get_state()
136 		ret = clk_enable(ddata->clk);  in pwm_sifive_enable()
138 			dev_err(ddata->chip.dev, "Enable clk failed\n");  in pwm_sifive_enable()
144 		clk_disable(ddata->clk);  in pwm_sifive_enable()
160 	if (state->polarity != PWM_POLARITY_INVERSED)  in pwm_sifive_apply()
161 		return -EINVAL;  in pwm_sifive_apply()
163 	ret = clk_enable(ddata->clk);  in pwm_sifive_apply()
165 		dev_err(ddata->chip.dev, "Enable clk failed\n");  in pwm_sifive_apply()
169 	mutex_lock(&ddata->lock);  in pwm_sifive_apply()
170 	cur_state = pwm->state;  in pwm_sifive_apply()
173 	duty_cycle = state->duty_cycle;  in pwm_sifive_apply()
174 	if (!state->enabled)  in pwm_sifive_apply()
184 	frac = DIV64_U64_ROUND_CLOSEST(num, state->period);  in pwm_sifive_apply()
186 	frac = min(frac, (1U << PWM_SIFIVE_CMPWIDTH) - 1);  in pwm_sifive_apply()
188 	if (state->period != ddata->approx_period) {  in pwm_sifive_apply()
189 		if (ddata->user_count != 1) {  in pwm_sifive_apply()
190 			ret = -EBUSY;  in pwm_sifive_apply()
193 		ddata->approx_period = state->period;  in pwm_sifive_apply()
194 		pwm_sifive_update_clock(ddata, clk_get_rate(ddata->clk));  in pwm_sifive_apply()
197 	writel(frac, ddata->regs + PWM_SIFIVE_PWMCMP0 +  in pwm_sifive_apply()
198 	       pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP);  in pwm_sifive_apply()
200 	if (state->enabled != enabled)  in pwm_sifive_apply()
201 		pwm_sifive_enable(chip, state->enabled);  in pwm_sifive_apply()
204 	clk_disable(ddata->clk);  in pwm_sifive_apply()
205 	mutex_unlock(&ddata->lock);  in pwm_sifive_apply()
225 		pwm_sifive_update_clock(ddata, ndata->new_rate);  in pwm_sifive_clock_notifier()
232 	struct device *dev = &pdev->dev;  in pwm_sifive_probe()
240 		return -ENOMEM;  in pwm_sifive_probe()
242 	mutex_init(&ddata->lock);  in pwm_sifive_probe()
243 	chip = &ddata->chip;  in pwm_sifive_probe()
244 	chip->dev = dev;  in pwm_sifive_probe()
245 	chip->ops = &pwm_sifive_ops;  in pwm_sifive_probe()
246 	chip->of_xlate = of_pwm_xlate_with_flags;  in pwm_sifive_probe()
247 	chip->of_pwm_n_cells = 3;  in pwm_sifive_probe()
248 	chip->base = -1;  in pwm_sifive_probe()
249 	chip->npwm = 4;  in pwm_sifive_probe()
252 	ddata->regs = devm_ioremap_resource(dev, res);  in pwm_sifive_probe()
253 	if (IS_ERR(ddata->regs))  in pwm_sifive_probe()
254 		return PTR_ERR(ddata->regs);  in pwm_sifive_probe()
256 	ddata->clk = devm_clk_get(dev, NULL);  in pwm_sifive_probe()
257 	if (IS_ERR(ddata->clk))  in pwm_sifive_probe()
258 		return dev_err_probe(dev, PTR_ERR(ddata->clk),  in pwm_sifive_probe()
261 	ret = clk_prepare_enable(ddata->clk);  in pwm_sifive_probe()
268 	ddata->notifier.notifier_call = pwm_sifive_clock_notifier;  in pwm_sifive_probe()
269 	ret = clk_notifier_register(ddata->clk, &ddata->notifier);  in pwm_sifive_probe()
282 	dev_dbg(dev, "SiFive PWM chip registered %d PWMs\n", chip->npwm);  in pwm_sifive_probe()
287 	clk_notifier_unregister(ddata->clk, &ddata->notifier);  in pwm_sifive_probe()
289 	clk_disable_unprepare(ddata->clk);  in pwm_sifive_probe()
301 	for (ch = 0; ch < ddata->chip.npwm; ch++) {  in pwm_sifive_remove()
302 		pwm = &ddata->chip.pwms[ch];  in pwm_sifive_remove()
303 		if (pwm->state.enabled) {  in pwm_sifive_remove()
309 		clk_disable(ddata->clk);  in pwm_sifive_remove()
311 	clk_disable_unprepare(ddata->clk);  in pwm_sifive_remove()
312 	ret = pwmchip_remove(&ddata->chip);  in pwm_sifive_remove()
313 	clk_notifier_unregister(ddata->clk, &ddata->notifier);  in pwm_sifive_remove()
328 		.name = "pwm-sifive",