From 94be46b9e5e2954b6d5962750f8aae8b5f099baa Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 18 Apr 2016 15:33:10 +0200 Subject: regulator: s2mps11: Set default ramp delay for S2MPS11 LDOs Driver did not provide default value for ramp delay for LDOs which lead to warning in dmesg, e.g. on Odroid XU4: [ 1.486076] vdd_ldo9: ramp_delay not set [ 1.506875] vddq_mmc2: ramp_delay not set [ 1.523766] vdd_ldo15: ramp_delay not set [ 1.544702] vdd_sd: ramp_delay not set The datasheet for all the S2MPS1x family is inconsistent here and does not specify unambiguously the value of ramp delay for LDO. It mentions 30 mV/us in one timing diagram but then omits it completely in LDO regulator characteristics table (it is specified for bucks). However the vendor kernels for Galaxy S5 and Odroid XU3 use values of 12 mV/us or 24 mV/us. Without the ramp delay value the consumers do not wait for voltage settle after changing it. Although the proper value of ramp delay for LDOs is unknown, it seems safer to use at least some value from reference kernel than to leave it unset. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Mark Brown --- include/linux/mfd/samsung/core.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mfd/samsung/core.h b/include/linux/mfd/samsung/core.h index 6bc4bcd488ac..5a23dd4df432 100644 --- a/include/linux/mfd/samsung/core.h +++ b/include/linux/mfd/samsung/core.h @@ -30,6 +30,9 @@ #define MIN_600_MV 600000 #define MIN_500_MV 500000 +/* Ramp delay in uV/us */ +#define RAMP_DELAY_12_MVUS 12000 + /* Macros to represent steps for LDO/BUCK */ #define STEP_50_MV 50000 #define STEP_25_MV 25000 -- cgit v1.2.3 From e39c0df1be5a97e0910b09af1530bdf3de057a06 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Thu, 14 Apr 2016 21:17:21 +0200 Subject: pwm: Introduce the pwm_args concept Currently the PWM core mixes the current PWM state with the per-platform reference config (specified through the PWM lookup table, DT definition or directly hardcoded in PWM drivers). Create a struct pwm_args to store this reference configuration, so that PWM users can differentiate between the current and reference configurations. Patch all places where pwm->args should be initialized. We keep the pwm_set_polarity/period() calls until all PWM users are patched to use pwm_args instead of pwm_get_period/polarity(). Signed-off-by: Boris Brezillon [thierry.reding@gmail.com: reword kerneldoc comments] Signed-off-by: Thierry Reding --- include/linux/pwm.h | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'include/linux') diff --git a/include/linux/pwm.h b/include/linux/pwm.h index cfc3ed46cad2..b78d27c42629 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -74,6 +74,24 @@ enum pwm_polarity { PWM_POLARITY_INVERSED, }; +/** + * struct pwm_args - board-dependent PWM arguments + * @period: reference period + * @polarity: reference polarity + * + * This structure describes board-dependent arguments attached to a PWM + * device. These arguments are usually retrieved from the PWM lookup table or + * device tree. + * + * Do not confuse this with the PWM state: PWM arguments represent the initial + * configuration that users want to use on this PWM device rather than the + * current PWM hardware state. + */ +struct pwm_args { + unsigned int period; + enum pwm_polarity polarity; +}; + enum { PWMF_REQUESTED = 1 << 0, PWMF_ENABLED = 1 << 1, @@ -92,6 +110,7 @@ enum { * @period: period of the PWM signal (in nanoseconds) * @duty_cycle: duty cycle of the PWM signal (in nanoseconds) * @polarity: polarity of the PWM signal + * @args: PWM arguments */ struct pwm_device { const char *label; @@ -105,6 +124,8 @@ struct pwm_device { unsigned int period; unsigned int duty_cycle; enum pwm_polarity polarity; + + struct pwm_args args; }; static inline bool pwm_is_enabled(const struct pwm_device *pwm) @@ -144,6 +165,18 @@ static inline enum pwm_polarity pwm_get_polarity(const struct pwm_device *pwm) return pwm ? pwm->polarity : PWM_POLARITY_NORMAL; } +static inline void pwm_get_args(const struct pwm_device *pwm, + struct pwm_args *args) +{ + *args = pwm->args; +} + +static inline void pwm_apply_args(struct pwm_device *pwm) +{ + pwm_set_period(pwm, pwm->args.period); + pwm_set_polarity(pwm, pwm->args.polarity); +} + /** * struct pwm_ops - PWM controller operations * @request: optional hook for requesting a PWM -- cgit v1.2.3