1 // SPDX-License-Identifier: GPL-2.0
13 #include <linux/pwm.h>
46  * The list of clocks required by PWM channels, and each channel has 2 clocks:
47  * enable clock and pwm clock.
58 	u32 offset = reg + (hwid << SPRD_PWM_REGS_SHIFT);  in sprd_pwm_read()  local
60 	return readl_relaxed(spc->base + offset);  in sprd_pwm_read()
66 	u32 offset = reg + (hwid << SPRD_PWM_REGS_SHIFT);  in sprd_pwm_write()  local
68 	writel_relaxed(val, spc->base + offset);  in sprd_pwm_write()
71 static int sprd_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,  in sprd_pwm_get_state()  argument
75 	struct sprd_pwm_chn *chn = &spc->chn[pwm->hwpwm];  in sprd_pwm_get_state()
81 	 * The clocks to PWM channel has to be enabled first before  in sprd_pwm_get_state()
84 	ret = clk_bulk_prepare_enable(SPRD_PWM_CHN_CLKS_NUM, chn->clks);  in sprd_pwm_get_state()
86 		dev_err(pwmchip_parent(chip), "failed to enable pwm%u clocks\n",  in sprd_pwm_get_state()
87 			pwm->hwpwm);  in sprd_pwm_get_state()
91 	val = sprd_pwm_read(spc, pwm->hwpwm, SPRD_PWM_ENABLE);  in sprd_pwm_get_state()
93 		state->enabled = true;  in sprd_pwm_get_state()
95 		state->enabled = false;  in sprd_pwm_get_state()
105 	val = sprd_pwm_read(spc, pwm->hwpwm, SPRD_PWM_PRESCALE);  in sprd_pwm_get_state()
108 	state->period = DIV_ROUND_CLOSEST_ULL(tmp, chn->clk_rate);  in sprd_pwm_get_state()
110 	val = sprd_pwm_read(spc, pwm->hwpwm, SPRD_PWM_DUTY);  in sprd_pwm_get_state()
113 	state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, chn->clk_rate);  in sprd_pwm_get_state()
114 	state->polarity = PWM_POLARITY_NORMAL;  in sprd_pwm_get_state()
116 	/* Disable PWM clocks if the PWM channel is not in enable state. */  in sprd_pwm_get_state()
117 	if (!state->enabled)  in sprd_pwm_get_state()
118 		clk_bulk_disable_unprepare(SPRD_PWM_CHN_CLKS_NUM, chn->clks);  in sprd_pwm_get_state()
123 static int sprd_pwm_config(struct sprd_pwm_chip *spc, struct pwm_device *pwm,  in sprd_pwm_config()  argument
126 	struct sprd_pwm_chn *chn = &spc->chn[pwm->hwpwm];  in sprd_pwm_config()
142 	tmp = (u64)chn->clk_rate * period_ns;  in sprd_pwm_config()
144 	prescale = DIV_ROUND_CLOSEST_ULL(tmp, SPRD_PWM_MOD_MAX) - 1;  in sprd_pwm_config()
156 	sprd_pwm_write(spc, pwm->hwpwm, SPRD_PWM_PRESCALE, prescale);  in sprd_pwm_config()
157 	sprd_pwm_write(spc, pwm->hwpwm, SPRD_PWM_MOD, SPRD_PWM_MOD_MAX);  in sprd_pwm_config()
158 	sprd_pwm_write(spc, pwm->hwpwm, SPRD_PWM_DUTY, duty);  in sprd_pwm_config()
163 static int sprd_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,  in sprd_pwm_apply()  argument
167 	struct sprd_pwm_chn *chn = &spc->chn[pwm->hwpwm];  in sprd_pwm_apply()
168 	struct pwm_state *cstate = &pwm->state;  in sprd_pwm_apply()
171 	if (state->polarity != PWM_POLARITY_NORMAL)  in sprd_pwm_apply()
172 		return -EINVAL;  in sprd_pwm_apply()
174 	if (state->enabled) {  in sprd_pwm_apply()
175 		if (!cstate->enabled) {  in sprd_pwm_apply()
177 			 * The clocks to PWM channel has to be enabled first  in sprd_pwm_apply()
181 						      chn->clks);  in sprd_pwm_apply()
184 					"failed to enable pwm%u clocks\n",  in sprd_pwm_apply()
185 					pwm->hwpwm);  in sprd_pwm_apply()
190 		ret = sprd_pwm_config(spc, pwm, state->duty_cycle,  in sprd_pwm_apply()
191 				      state->period);  in sprd_pwm_apply()
195 		sprd_pwm_write(spc, pwm->hwpwm, SPRD_PWM_ENABLE, 1);  in sprd_pwm_apply()
196 	} else if (cstate->enabled) {  in sprd_pwm_apply()
200 		 * will stop the PWM channel immediately.  in sprd_pwm_apply()
202 		sprd_pwm_write(spc, pwm->hwpwm, SPRD_PWM_ENABLE, 0);  in sprd_pwm_apply()
204 		clk_bulk_disable_unprepare(SPRD_PWM_CHN_CLKS_NUM, chn->clks);  in sprd_pwm_apply()
231 			if (ret == -ENOENT)  in sprd_pwm_clk_init()
243 		return dev_err_probe(dev, -ENODEV, "no available PWM channels\n");  in sprd_pwm_clk_init()
255 	npwm = sprd_pwm_clk_init(&pdev->dev, chn);  in sprd_pwm_probe()
259 	chip = devm_pwmchip_alloc(&pdev->dev, npwm, sizeof(*spc));  in sprd_pwm_probe()
264 	spc->base = devm_platform_ioremap_resource(pdev, 0);  in sprd_pwm_probe()
265 	if (IS_ERR(spc->base))  in sprd_pwm_probe()
266 		return PTR_ERR(spc->base);  in sprd_pwm_probe()
268 	memcpy(spc->chn, chn, sizeof(chn));  in sprd_pwm_probe()
270 	chip->ops = &sprd_pwm_ops;  in sprd_pwm_probe()
272 	ret = devm_pwmchip_add(&pdev->dev, chip);  in sprd_pwm_probe()
274 		dev_err(&pdev->dev, "failed to add PWM chip\n");  in sprd_pwm_probe()
280 	{ .compatible = "sprd,ums512-pwm", },
287 		.name = "sprd-pwm",
295 MODULE_DESCRIPTION("Spreadtrum PWM Driver");