drivers/pwm/pwm-samsung.c

9  * PWM driver for Samsung SoCs
21 #include <linux/pwm.h>
59  * struct samsung_pwm_channel - private data of PWM channel
71  * struct samsung_pwm_chip - private data of PWM chip
75  * @base:		base address of mapped PWM registers
95  * PWM block is shared between pwm-samsung and samsung_pwm_timer drivers
101  * because all the supported SoCs contain only one instance of the PWM
121 				      struct pwm_device *pwm)  in __pwm_samsung_manual_update()  argument
123 	unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);  in __pwm_samsung_manual_update()
200 			"tclk of PWM %d is inoperational, using tdiv\n", chan);  in pwm_samsung_calc_tin()
207 	 * Compare minimum PWM frequency that can be achieved with possible  in pwm_samsung_calc_tin()
229 static int pwm_samsung_request(struct pwm_chip *chip, struct pwm_device *pwm)  in pwm_samsung_request()  argument
233 	if (!(our_chip->variant.output_mask & BIT(pwm->hwpwm))) {  in pwm_samsung_request()
235 			"tried to request PWM channel %d without output\n",  in pwm_samsung_request()
236 			pwm->hwpwm);  in pwm_samsung_request()
240 	memset(&our_chip->channel[pwm->hwpwm], 0, sizeof(our_chip->channel[pwm->hwpwm]));  in pwm_samsung_request()
245 static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm)  in pwm_samsung_enable()  argument
248 	unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);  in pwm_samsung_enable()
264 	our_chip->disabled_mask &= ~BIT(pwm->hwpwm);  in pwm_samsung_enable()
271 static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm)  in pwm_samsung_disable()  argument
274 	unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);  in pwm_samsung_disable()
285 	 * In case the PWM is at 100% duty cycle, force a manual  in pwm_samsung_disable()
288 	if (readl(our_chip->base + REG_TCMPB(pwm->hwpwm)) == (u32)-1U)  in pwm_samsung_disable()
289 		__pwm_samsung_manual_update(our_chip, pwm);  in pwm_samsung_disable()
291 	our_chip->disabled_mask |= BIT(pwm->hwpwm);  in pwm_samsung_disable()
297 				      struct pwm_device *pwm)  in pwm_samsung_manual_update()  argument
303 	__pwm_samsung_manual_update(our_chip, pwm);  in pwm_samsung_manual_update()
308 static int __pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,  in __pwm_samsung_config()  argument
312 	struct samsung_pwm_channel *chan = &our_chip->channel[pwm->hwpwm];  in __pwm_samsung_config()
315 	tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm));  in __pwm_samsung_config()
316 	oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm));  in __pwm_samsung_config()
321 	/* Check to see if we are changing the clock rate of the PWM. */  in __pwm_samsung_config()
331 		tin_rate = pwm_samsung_calc_tin(chip, pwm->hwpwm, period);  in __pwm_samsung_config()
359 	/* Update PWM registers. */  in __pwm_samsung_config()
360 	writel(tcnt, our_chip->base + REG_TCNTB(pwm->hwpwm));  in __pwm_samsung_config()
361 	writel(tcmp, our_chip->base + REG_TCMPB(pwm->hwpwm));  in __pwm_samsung_config()
364 	 * In case the PWM is currently at 100% duty cycle, force a manual  in __pwm_samsung_config()
365 	 * update to prevent the signal staying high if the PWM is disabled  in __pwm_samsung_config()
370 		pwm_samsung_manual_update(our_chip, pwm);  in __pwm_samsung_config()
380 static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,  in pwm_samsung_config()  argument
383 	return __pwm_samsung_config(chip, pwm, duty_ns, period_ns, false);  in pwm_samsung_config()
411 				    struct pwm_device *pwm,  in pwm_samsung_set_polarity()  argument
418 	pwm_samsung_set_invert(our_chip, pwm->hwpwm, invert);  in pwm_samsung_set_polarity()
423 static int pwm_samsung_apply(struct pwm_chip *chip, struct pwm_device *pwm,  in pwm_samsung_apply()  argument
426 	int err, enabled = pwm->state.enabled;  in pwm_samsung_apply()
428 	if (state->polarity != pwm->state.polarity) {  in pwm_samsung_apply()
430 			pwm_samsung_disable(chip, pwm);  in pwm_samsung_apply()
434 		err = pwm_samsung_set_polarity(chip, pwm, state->polarity);  in pwm_samsung_apply()
441 			pwm_samsung_disable(chip, pwm);  in pwm_samsung_apply()
454 	err = pwm_samsung_config(chip, pwm, state->duty_cycle, state->period);  in pwm_samsung_apply()
458 	if (!pwm->state.enabled)  in pwm_samsung_apply()
459 		err = pwm_samsung_enable(chip, pwm);  in pwm_samsung_apply()
499 	{ .compatible = "samsung,s3c2410-pwm", .data = &s3c24xx_variant },
500 	{ .compatible = "samsung,s3c6400-pwm", .data = &s3c64xx_variant },
501 	{ .compatible = "samsung,s5p6440-pwm", .data = &s5p64x0_variant },
502 	{ .compatible = "samsung,s5pc100-pwm", .data = &s5pc100_variant },
503 	{ .compatible = "samsung,exynos4210-pwm", .data = &s5p64x0_variant },
521 	of_property_for_each_u32(np, "samsung,pwm-outputs", val) {  in pwm_samsung_parse_dt()
524 				"%s: invalid channel index in samsung,pwm-outputs property\n",  in pwm_samsung_parse_dt()
583 	our_chip->tclk0 = devm_clk_get(&pdev->dev, "pwm-tclk0");  in pwm_samsung_probe()
584 	our_chip->tclk1 = devm_clk_get(&pdev->dev, "pwm-tclk1");  in pwm_samsung_probe()
590 		return dev_err_probe(dev, ret, "failed to register PWM chip\n");  in pwm_samsung_probe()
607 		struct pwm_device *pwm = &chip->pwms[i];  in pwm_samsung_resume()  local
610 		if (!test_bit(PWMF_REQUESTED, &pwm->flags))  in pwm_samsung_resume()
618 			__pwm_samsung_config(chip, pwm, chan->duty_ns,  in pwm_samsung_resume()
620 			/* needed to make PWM disable work on Odroid-XU3 */  in pwm_samsung_resume()
621 			pwm_samsung_manual_update(our_chip, pwm);  in pwm_samsung_resume()
625 			pwm_samsung_disable(chip, pwm);  in pwm_samsung_resume()
627 			pwm_samsung_enable(chip, pwm);  in pwm_samsung_resume()
637 		.name	= "samsung-pwm",
648 MODULE_ALIAS("platform:samsung-pwm");