3  * Intel Low Power Subsystem PWM controller driver
24 #include "pwm-lpss.h"
26 #define PWM				0x00000000  macro
32 /* Size of each PWM register space if multiple */
74 static inline u32 pwm_lpss_read(const struct pwm_device *pwm)  in pwm_lpss_read()  argument
76 	struct pwm_lpss_chip *lpwm = to_lpwm(pwm->chip);  in pwm_lpss_read()
78 	return readl(lpwm->regs + pwm->hwpwm * PWM_SIZE + PWM);  in pwm_lpss_read()
81 static inline void pwm_lpss_write(const struct pwm_device *pwm, u32 value)  in pwm_lpss_write()  argument
83 	struct pwm_lpss_chip *lpwm = to_lpwm(pwm->chip);  in pwm_lpss_write()
85 	writel(value, lpwm->regs + pwm->hwpwm * PWM_SIZE + PWM);  in pwm_lpss_write()
88 static int pwm_lpss_wait_for_update(struct pwm_device *pwm)  in pwm_lpss_wait_for_update()  argument
90 	struct pwm_lpss_chip *lpwm = to_lpwm(pwm->chip);  in pwm_lpss_wait_for_update()
91 	const void __iomem *addr = lpwm->regs + pwm->hwpwm * PWM_SIZE + PWM;  in pwm_lpss_wait_for_update()
97 	 * PWM Configuration register has SW_UPDATE bit that is set when a new  in pwm_lpss_wait_for_update()
102 	 * the bit enabled, PWM may freeze. That is, while one can still write  in pwm_lpss_wait_for_update()
109 		dev_err(pwm->chip->dev, "PWM_SW_UPDATE was not cleared\n");  in pwm_lpss_wait_for_update()
114 static inline int pwm_lpss_is_updating(struct pwm_device *pwm)  in pwm_lpss_is_updating()  argument
116 	if (pwm_lpss_read(pwm) & PWM_SW_UPDATE) {  in pwm_lpss_is_updating()
117 		dev_err(pwm->chip->dev, "PWM_SW_UPDATE is still set, skipping update\n");  in pwm_lpss_is_updating()
124 static void pwm_lpss_prepare(struct pwm_lpss_chip *lpwm, struct pwm_device *pwm,  in pwm_lpss_prepare()  argument
149 	ctrl = pwm_lpss_read(pwm);  in pwm_lpss_prepare()
155 	pwm_lpss_write(pwm, ctrl);  in pwm_lpss_prepare()
156 	pwm_lpss_write(pwm, ctrl | PWM_SW_UPDATE);  in pwm_lpss_prepare()
159 static inline void pwm_lpss_cond_enable(struct pwm_device *pwm, bool cond)  in pwm_lpss_cond_enable()  argument
162 		pwm_lpss_write(pwm, pwm_lpss_read(pwm) | PWM_ENABLE);  in pwm_lpss_cond_enable()
166 				   struct pwm_device *pwm,  in pwm_lpss_prepare_enable()  argument
171 	ret = pwm_lpss_is_updating(pwm);  in pwm_lpss_prepare_enable()
175 	pwm_lpss_prepare(lpwm, pwm, state->duty_cycle, state->period);  in pwm_lpss_prepare_enable()
176 	pwm_lpss_cond_enable(pwm, lpwm->info->bypass == false);  in pwm_lpss_prepare_enable()
177 	ret = pwm_lpss_wait_for_update(pwm);  in pwm_lpss_prepare_enable()
181 	pwm_lpss_cond_enable(pwm, lpwm->info->bypass == true);  in pwm_lpss_prepare_enable()
185 static int pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm,  in pwm_lpss_apply()  argument
192 		if (!pwm_is_enabled(pwm)) {  in pwm_lpss_apply()
194 			ret = pwm_lpss_prepare_enable(lpwm, pwm, state);  in pwm_lpss_apply()
198 			ret = pwm_lpss_prepare_enable(lpwm, pwm, state);  in pwm_lpss_apply()
200 	} else if (pwm_is_enabled(pwm)) {  in pwm_lpss_apply()
201 		pwm_lpss_write(pwm, pwm_lpss_read(pwm) & ~PWM_ENABLE);  in pwm_lpss_apply()
208 static void pwm_lpss_get_state(struct pwm_chip *chip, struct pwm_device *pwm,  in pwm_lpss_get_state()  argument
220 	ctrl = pwm_lpss_read(pwm);  in pwm_lpss_get_state()
275 		dev_err(dev, "failed to add PWM chip: %d\n", ret);  in pwm_lpss_probe()
289 MODULE_DESCRIPTION("PWM driver for Intel LPSS");