diff options
| -rw-r--r-- | drivers/platform/chrome/cros_ec_proto.c | 17 | ||||
| -rw-r--r-- | drivers/pwm/core.c | 3 | ||||
| -rw-r--r-- | drivers/pwm/pwm-atmel-hlcdc.c | 2 | ||||
| -rw-r--r-- | drivers/pwm/sysfs.c | 2 | ||||
| -rw-r--r-- | include/linux/mfd/cros_ec.h | 15 | ||||
| -rw-r--r-- | include/linux/mfd/cros_ec_commands.h | 31 | ||||
| -rw-r--r-- | include/linux/pwm.h | 108 |
7 files changed, 168 insertions, 10 deletions
diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index b6e161f..6c084b2 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -380,3 +380,20 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, return ret; } EXPORT_SYMBOL(cros_ec_cmd_xfer); + +int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg) +{ + int ret; + + ret = cros_ec_cmd_xfer(ec_dev, msg); + if (ret < 0) { + dev_err(ec_dev->dev, "Command xfer error (err:%d)\n", ret); + } else if (msg->result != EC_RES_SUCCESS) { + dev_dbg(ec_dev->dev, "Command result (err: %d)\n", msg->result); + return -EPROTO; + } + + return ret; +} +EXPORT_SYMBOL(cros_ec_cmd_xfer_status); diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 8f40604..0dbd29e 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -457,7 +457,8 @@ int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state) { int err; - if (!pwm) + if (!pwm || !state || !state->period || + state->duty_cycle > state->period) return -EINVAL; if (!memcmp(state, &pwm->state, sizeof(*state))) diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c index f994c7e..14fc011 100644 --- a/drivers/pwm/pwm-atmel-hlcdc.c +++ b/drivers/pwm/pwm-atmel-hlcdc.c @@ -272,7 +272,7 @@ static int atmel_hlcdc_pwm_probe(struct platform_device *pdev) chip->chip.of_pwm_n_cells = 3; chip->chip.can_sleep = 1; - ret = pwmchip_add(&chip->chip); + ret = pwmchip_add_with_polarity(&chip->chip, PWM_POLARITY_INVERSED); if (ret) { clk_disable_unprepare(hlcdc->periph_clk); return ret; diff --git a/drivers/pwm/sysfs.c b/drivers/pwm/sysfs.c index c3b1b56..18ed725 100644 --- a/drivers/pwm/sysfs.c +++ b/drivers/pwm/sysfs.c @@ -152,7 +152,7 @@ static ssize_t enable_store(struct device *child, goto unlock; } - pwm_apply_state(pwm, &state); + ret = pwm_apply_state(pwm, &state); unlock: mutex_unlock(&export->lock); diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h index 64184d2..d641a18 100644 --- a/include/linux/mfd/cros_ec.h +++ b/include/linux/mfd/cros_ec.h @@ -226,6 +226,21 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, struct cros_ec_command *msg); /** + * cros_ec_cmd_xfer_status - Send a command to the ChromeOS EC + * + * This function is identical to cros_ec_cmd_xfer, except it returns success + * status only if both the command was transmitted successfully and the EC + * replied with success status. It's not necessary to check msg->result when + * using this function. + * + * @ec_dev: EC device + * @msg: Message to write + * @return: Num. of bytes transferred on success, <0 on failure + */ +int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg); + +/** * cros_ec_remove - Remove a ChromeOS EC * * Call this to deregister a ChromeOS EC, then clean up any private data. diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h index 13b630c..7e7a8d4 100644 --- a/include/linux/mfd/cros_ec_commands.h +++ b/include/linux/mfd/cros_ec_commands.h @@ -949,6 +949,37 @@ struct ec_params_pwm_set_fan_duty { uint32_t percent; } __packed; +#define EC_CMD_PWM_SET_DUTY 0x25 +/* 16 bit duty cycle, 0xffff = 100% */ +#define EC_PWM_MAX_DUTY 0xffff + +enum ec_pwm_type { + /* All types, indexed by board-specific enum pwm_channel */ + EC_PWM_TYPE_GENERIC = 0, + /* Keyboard backlight */ + EC_PWM_TYPE_KB_LIGHT, + /* Display backlight */ + EC_PWM_TYPE_DISPLAY_LIGHT, + EC_PWM_TYPE_COUNT, +}; + +struct ec_params_pwm_set_duty { + uint16_t duty; /* Duty cycle, EC_PWM_MAX_DUTY = 100% */ + uint8_t pwm_type; /* ec_pwm_type */ + uint8_t index; /* Type-specific index, or 0 if unique */ +} __packed; + +#define EC_CMD_PWM_GET_DUTY 0x26 + +struct ec_params_pwm_get_duty { + uint8_t pwm_type; /* ec_pwm_type */ + uint8_t index; /* Type-specific index, or 0 if unique */ +} __packed; + +struct ec_response_pwm_get_duty { + uint16_t duty; /* Duty cycle, EC_PWM_MAX_DUTY = 100% */ +} __packed; + /*****************************************************************************/ /* * Lightbar commands. This looks worse than it is. Since we only use one HOST diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 8402b5d..f1bbae0 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -150,6 +150,94 @@ static inline void pwm_get_args(const struct pwm_device *pwm, } /** + * pwm_init_state() - prepare a new state to be applied with pwm_apply_state() + * @pwm: PWM device + * @state: state to fill with the prepared PWM state + * + * This functions prepares a state that can later be tweaked and applied + * to the PWM device with pwm_apply_state(). This is a convenient function + * that first retrieves the current PWM state and the replaces the period + * and polarity fields with the reference values defined in pwm->args. + * Once the function returns, you can adjust the ->enabled and ->duty_cycle + * fields according to your needs before calling pwm_apply_state(). + * + * ->duty_cycle is initially set to zero to avoid cases where the current + * ->duty_cycle value exceed the pwm_args->period one, which would trigger + * an error if the user calls pwm_apply_state() without adjusting ->duty_cycle + * first. + */ +static inline void pwm_init_state(const struct pwm_device *pwm, + struct pwm_state *state) +{ + struct pwm_args args; + + /* First get the current state. */ + pwm_get_state(pwm, state); + + /* Then fill it with the reference config */ + pwm_get_args(pwm, &args); + + state->period = args.period; + state->polarity = args.polarity; + state->duty_cycle = 0; +} + +/** + * pwm_get_relative_duty_cycle() - Get a relative duty cycle value + * @state: PWM state to extract the duty cycle from + * @scale: target scale of the relative duty cycle + * + * This functions converts the absolute duty cycle stored in @state (expressed + * in nanosecond) into a value relative to the period. + * + * For example if you want to get the duty_cycle expressed in percent, call: + * + * pwm_get_state(pwm, &state); + * duty = pwm_get_relative_duty_cycle(&state, 100); + */ +static inline unsigned int +pwm_get_relative_duty_cycle(const struct pwm_state *state, unsigned int scale) +{ + if (!state->period) + return 0; + + return DIV_ROUND_CLOSEST_ULL((u64)state->duty_cycle * scale, + state->period); +} + +/** + * pwm_set_relative_duty_cycle() - Set a relative duty cycle value + * @state: PWM state to fill + * @duty_cycle: relative duty cycle value + * @scale: scale in which @duty_cycle is expressed + * + * This functions converts a relative into an absolute duty cycle (expressed + * in nanoseconds), and puts the result in state->duty_cycle. + * + * For example if you want to configure a 50% duty cycle, call: + * + * pwm_init_state(pwm, &state); + * pwm_set_relative_duty_cycle(&state, 50, 100); + * pwm_apply_state(pwm, &state); + * + * This functions returns -EINVAL if @duty_cycle and/or @scale are + * inconsistent (@scale == 0 or @duty_cycle > @scale). + */ +static inline int +pwm_set_relative_duty_cycle(struct pwm_state *state, unsigned int duty_cycle, + unsigned int scale) +{ + if (!scale || duty_cycle > scale) + return -EINVAL; + + state->duty_cycle = DIV_ROUND_CLOSEST_ULL((u64)duty_cycle * + state->period, + scale); + + return 0; +} + +/** * struct pwm_ops - PWM controller operations * @request: optional hook for requesting a PWM * @free: optional hook for freeing a PWM @@ -250,6 +338,9 @@ static inline int pwm_config(struct pwm_device *pwm, int duty_ns, if (!pwm) return -EINVAL; + if (duty_ns < 0 || period_ns < 0) + return -EINVAL; + pwm_get_state(pwm, &state); if (state.duty_cycle == duty_ns && state.period == period_ns) return 0; @@ -335,7 +426,6 @@ static inline void pwm_disable(struct pwm_device *pwm) pwm_apply_state(pwm, &state); } - /* PWM provider APIs */ int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, unsigned long timeout); @@ -485,6 +575,8 @@ static inline bool pwm_can_sleep(struct pwm_device *pwm) static inline void pwm_apply_args(struct pwm_device *pwm) { + struct pwm_state state = { }; + /* * PWM users calling pwm_apply_args() expect to have a fresh config * where the polarity and period are set according to pwm_args info. @@ -497,18 +589,20 @@ static inline void pwm_apply_args(struct pwm_device *pwm) * at startup (even if they are actually enabled), thus authorizing * polarity setting. * - * Instead of setting ->enabled to false, we call pwm_disable() - * before pwm_set_polarity() to ensure that everything is configured - * as expected, and the PWM is really disabled when the user request - * it. + * To fulfill this requirement, we apply a new state which disables + * the PWM device and set the reference period and polarity config. * * Note that PWM users requiring a smooth handover between the * bootloader and the kernel (like critical regulators controlled by * PWM devices) will have to switch to the atomic API and avoid calling * pwm_apply_args(). */ - pwm_disable(pwm); - pwm_set_polarity(pwm, pwm->args.polarity); + + state.enabled = false; + state.polarity = pwm->args.polarity; + state.period = pwm->args.period; + + pwm_apply_state(pwm, &state); } struct pwm_lookup { |
