1 // SPDX-License-Identifier: GPL-2.0-only
3  * Toshiba Visconti pulse-width-modulation controller driver
5  * Copyright (c) 2020 - 2021 TOSHIBA CORPORATION
6  * Copyright (c) 2020 - 2021 Toshiba Electronic Devices & Storage Corporation
11  * - The fixed input clock is running at 1 MHz and is divided by either 1,
13  * - When the settings of the PWM are modified, the new values are shadowed
17  * - Disabling the hardware completes the currently running period and keeps
33 #define PIPGM_PWMC_CLK_MASK		GENMASK(1, 0)
51 	if (!state->enabled) {  in visconti_pwm_apply()
52 		writel(0, priv->base + PIPGM_PCSR(pwm->hwpwm));  in visconti_pwm_apply()
62 	if (state->period > (0xffff << 3) * 1000)  in visconti_pwm_apply()
65 		period = state->period;  in visconti_pwm_apply()
67 	if (state->duty_cycle > period)  in visconti_pwm_apply()
70 		duty_cycle = state->duty_cycle;  in visconti_pwm_apply()
73 	 * The input clock runs fixed at 1 MHz, so we have only  in visconti_pwm_apply()
81 		return -ERANGE;  in visconti_pwm_apply()
85 	 * between 1 and 8. As a smaller divider yields higher precision, pick  in visconti_pwm_apply()
86 	 * the smallest possible one. As period is at most 0xffff << 3, pwmc0 is  in visconti_pwm_apply()
91 		return -EINVAL;  in visconti_pwm_apply()
96 	if (state->polarity == PWM_POLARITY_INVERSED)  in visconti_pwm_apply()
98 	writel(pwmc0, priv->base + PIPGM_PWMC(pwm->hwpwm));  in visconti_pwm_apply()
99 	writel(duty_cycle, priv->base + PIPGM_PDUT(pwm->hwpwm));  in visconti_pwm_apply()
100 	writel(period, priv->base + PIPGM_PCSR(pwm->hwpwm));  in visconti_pwm_apply()
111 	period = readl(priv->base + PIPGM_PCSR(pwm->hwpwm));  in visconti_pwm_get_state()
112 	duty = readl(priv->base + PIPGM_PDUT(pwm->hwpwm));  in visconti_pwm_get_state()
113 	pwmc0 = readl(priv->base + PIPGM_PWMC(pwm->hwpwm));  in visconti_pwm_get_state()
116 	state->period = (period << pwmc0_clk) * NSEC_PER_USEC;  in visconti_pwm_get_state()
117 	state->duty_cycle = (duty << pwmc0_clk) * NSEC_PER_USEC;  in visconti_pwm_get_state()
119 		state->polarity = PWM_POLARITY_INVERSED;  in visconti_pwm_get_state()
121 		state->polarity = PWM_POLARITY_NORMAL;  in visconti_pwm_get_state()
123 	state->enabled = true;  in visconti_pwm_get_state()
135 	struct device *dev = &pdev->dev;  in visconti_pwm_probe()
145 	priv->base = devm_platform_ioremap_resource(pdev, 0);  in visconti_pwm_probe()
146 	if (IS_ERR(priv->base))  in visconti_pwm_probe()
147 		return PTR_ERR(priv->base);  in visconti_pwm_probe()
149 	chip->ops = &visconti_pwm_ops;  in visconti_pwm_probe()
151 	ret = devm_pwmchip_add(&pdev->dev, chip);  in visconti_pwm_probe()
153 		return dev_err_probe(&pdev->dev, ret, "Cannot register visconti PWM\n");  in visconti_pwm_probe()
159 	{ .compatible = "toshiba,visconti-pwm", },
166 		.name = "pwm-visconti",
176 MODULE_ALIAS("platform:pwm-visconti");