Merge branch 'bugfix/clear_ledc_gamma_ram_v5.1' into 'release/v5.1'

fix(ledc): left-off gamma ram registers should be cleared (v5.1) See merge request espressif/esp-idf!37577
2025-03-11 10:37:09 +08:00
parent f16e65b193 95dc2c57ca
commit 63da8bb6c2
7 changed files with 71 additions and 17 deletions
--- a/components/driver/ledc/include/driver/ledc.h
+++ b/components/driver/ledc/include/driver/ledc.h
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */
@@ -413,7 +413,18 @@ esp_err_t ledc_set_fade_with_step(ledc_mode_t speed_mode, ledc_channel_t channel
 * @param speed_mode Select the LEDC channel group with specified speed mode. Note that not all targets support high speed mode.
 * @param channel LEDC channel index (0 - LEDC_CHANNEL_MAX-1), select from ledc_channel_t
 * @param target_duty Target duty of fading [0, (2**duty_resolution)]
- * @param max_fade_time_ms The maximum time of the fading ( ms ).
+ * @param desired_fade_time_ms The intended time of the fading ( ms ).
+ *                             Note that the actual time it takes to complete the fade could vary by a factor of up to 2x shorter
+ *                             or longer than the expected time due to internal rounding errors in calculations.
+ *                             Specifically:
+ *                             * The total number of cycles (total_cycle_num = desired_fade_time_ms * freq / 1000)
+ *                             * The difference in duty cycle (duty_delta = |target_duty - current_duty|)
+ *                             The fade may complete faster than expected if total_cycle_num larger than duty_delta. Conversely,
+ *                             it may take longer than expected if total_cycle_num is less than duty_delta.
+ *                             The closer the ratio of total_cycle_num/duty_delta (or its inverse) is to a whole number (the floor value),
+ *                             the more accurately the actual fade duration will match the intended time.
+ *                             If an exact fade time is expected, please consider to split the entire fade into several smaller linear fades.
+ *                             The split should make each fade step has a divisible total_cycle_num/duty_delta (or its inverse) ratio.
 *
 * @return
 *     - ESP_OK Success
@@ -421,7 +432,7 @@ esp_err_t ledc_set_fade_with_step(ledc_mode_t speed_mode, ledc_channel_t channel
 *     - ESP_ERR_INVALID_STATE Channel not initialized
 *     - ESP_FAIL Fade function init error
 */
-esp_err_t ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, int max_fade_time_ms);
+esp_err_t ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, int desired_fade_time_ms);

 /**
 * @brief Install LEDC fade function. This function will occupy interrupt of LEDC module.
@@ -511,7 +522,18 @@ esp_err_t ledc_set_duty_and_update(ledc_mode_t speed_mode, ledc_channel_t channe
 * @param speed_mode Select the LEDC channel group with specified speed mode. Note that not all targets support high speed mode.
 * @param channel LEDC channel index (0 - LEDC_CHANNEL_MAX-1), select from ledc_channel_t
 * @param target_duty Target duty of fading [0, (2**duty_resolution)]
- * @param max_fade_time_ms The maximum time of the fading ( ms ).
+ * @param desired_fade_time_ms The intended time of the fading ( ms ).
+ *                             Note that the actual time it takes to complete the fade could vary by a factor of up to 2x shorter
+ *                             or longer than the expected time due to internal rounding errors in calculations.
+ *                             Specifically:
+ *                             * The total number of cycles (total_cycle_num = desired_fade_time_ms * freq / 1000)
+ *                             * The difference in duty cycle (duty_delta = |target_duty - current_duty|)
+ *                             The fade may complete faster than expected if total_cycle_num larger than duty_delta. Conversely,
+ *                             it may take longer than expected if total_cycle_num is less than duty_delta.
+ *                             The closer the ratio of total_cycle_num/duty_delta (or its inverse) is to a whole number (the floor value),
+ *                             the more accurately the actual fade duration will match the intended time.
+ *                             If an exact fade time is expected, please consider to split the entire fade into several smaller linear fades.
+ *                             The split should make each fade step has a divisible total_cycle_num/duty_delta (or its inverse) ratio.
 * @param fade_mode choose blocking or non-blocking mode
 *
 * @return
@@ -520,7 +542,7 @@ esp_err_t ledc_set_duty_and_update(ledc_mode_t speed_mode, ledc_channel_t channe
 *     - ESP_ERR_INVALID_STATE Channel not initialized
 *     - ESP_FAIL Fade function init error
 */
-esp_err_t ledc_set_fade_time_and_start(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, uint32_t max_fade_time_ms, ledc_fade_mode_t fade_mode);
+esp_err_t ledc_set_fade_time_and_start(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, uint32_t desired_fade_time_ms, ledc_fade_mode_t fade_mode);

 /**
 * @brief A thread-safe API to set and start LEDC fade function.
--- a/components/driver/ledc/ledc.c
+++ b/components/driver/ledc/ledc.c
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */
@@ -212,6 +212,8 @@ int duty_val, ledc_duty_direction_t duty_direction, uint32_t duty_num, uint32_t
 #if SOC_LEDC_GAMMA_CURVE_FADE_SUPPORTED
    ledc_hal_set_duty_range_wr_addr(&(p_ledc_obj[speed_mode]->ledc_hal), channel, 0);
    ledc_hal_set_range_number(&(p_ledc_obj[speed_mode]->ledc_hal), channel, 1);
+    // Clear left-off LEDC gamma ram registers, random data in ram could cause output waveform error
+    ledc_hal_clear_left_off_fade_param(&(p_ledc_obj[speed_mode]->ledc_hal), channel, 1);
 #endif
    return ESP_OK;
 }
@@ -602,7 +604,7 @@ esp_err_t ledc_channel_config(const ledc_channel_config_t *ledc_conf)
    /*set channel parameters*/
    /*   channel parameters decide how the waveform looks like in one period */
    /*   set channel duty and hpoint value, duty range is [0, (2**duty_res)], hpoint range is [0, (2**duty_res)-1] */
-    /*   Note: On ESP32, ESP32S2, ESP32S3, ESP32C3, ESP32C2, ESP32C6, ESP32H2, due to a hardware bug,
+    /*   Note: On ESP32, ESP32S2, ESP32S3, ESP32C3, ESP32C2, ESP32C6, ESP32H2 (rev < 1.2), due to a hardware bug,
     *         100% duty cycle (i.e. 2**duty_res) is not reachable when the binded timer selects the maximum duty
     *         resolution. For example, the max duty resolution on ESP32C3 is 14-bit width, then set duty to (2**14)
     *         will mess up the duty calculation in hardware.
@@ -1012,7 +1014,7 @@ static esp_err_t _ledc_set_fade_with_step(ledc_mode_t speed_mode, ledc_channel_t
    return ESP_OK;
 }

-static esp_err_t _ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, int max_fade_time_ms)
+static esp_err_t _ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, int desired_fade_time_ms)
 {
    ledc_timer_t timer_sel;
    uint32_t duty_cur = 0;
@@ -1024,7 +1026,7 @@ static esp_err_t _ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t
    if (duty_delta == 0) {
        return _ledc_set_fade_with_step(speed_mode, channel, target_duty, 0, 0);
    }
-    uint32_t total_cycles = max_fade_time_ms * freq / 1000;
+    uint32_t total_cycles = desired_fade_time_ms * freq / 1000;
    if (total_cycles == 0) {
        ESP_LOGW(LEDC_TAG, LEDC_FADE_TOO_FAST_STR);
        return _ledc_set_fade_with_step(speed_mode, channel, target_duty, 0, 0);
@@ -1071,7 +1073,7 @@ static void _ledc_fade_start(ledc_mode_t speed_mode, ledc_channel_t channel, led
    }
 }

-esp_err_t ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, int max_fade_time_ms)
+esp_err_t ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, int desired_fade_time_ms)
 {
    LEDC_ARG_CHECK(speed_mode < LEDC_SPEED_MODE_MAX, "speed_mode");
    LEDC_ARG_CHECK(channel < LEDC_CHANNEL_MAX, "channel");
@@ -1080,7 +1082,7 @@ esp_err_t ledc_set_fade_with_time(ledc_mode_t speed_mode, ledc_channel_t channel
    LEDC_CHECK(ledc_fade_channel_init_check(speed_mode, channel) == ESP_OK, LEDC_FADE_INIT_ERROR_STR, ESP_FAIL);

    _ledc_fade_hw_acquire(speed_mode, channel);
-    _ledc_set_fade_with_time(speed_mode, channel, target_duty, max_fade_time_ms);
+    _ledc_set_fade_with_time(speed_mode, channel, target_duty, desired_fade_time_ms);
    _ledc_fade_hw_release(speed_mode, channel);
    return ESP_OK;
 }
@@ -1224,7 +1226,7 @@ esp_err_t ledc_set_duty_and_update(ledc_mode_t speed_mode, ledc_channel_t channe
    return ESP_OK;
 }

-esp_err_t ledc_set_fade_time_and_start(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, uint32_t max_fade_time_ms, ledc_fade_mode_t fade_mode)
+esp_err_t ledc_set_fade_time_and_start(ledc_mode_t speed_mode, ledc_channel_t channel, uint32_t target_duty, uint32_t desired_fade_time_ms, ledc_fade_mode_t fade_mode)
 {
    LEDC_ARG_CHECK(speed_mode < LEDC_SPEED_MODE_MAX, "speed_mode");
    LEDC_ARG_CHECK(channel < LEDC_CHANNEL_MAX, "channel");
@@ -1234,7 +1236,7 @@ esp_err_t ledc_set_fade_time_and_start(ledc_mode_t speed_mode, ledc_channel_t ch
    LEDC_ARG_CHECK(target_duty <= ledc_get_max_duty(speed_mode, channel), "target_duty");
    _ledc_op_lock_acquire(speed_mode, channel);
    _ledc_fade_hw_acquire(speed_mode, channel);
-    _ledc_set_fade_with_time(speed_mode, channel, target_duty, max_fade_time_ms);
+    _ledc_set_fade_with_time(speed_mode, channel, target_duty, desired_fade_time_ms);
    _ledc_fade_start(speed_mode, channel, fade_mode);
    _ledc_op_lock_release(speed_mode, channel);
    return ESP_OK;
@@ -1274,6 +1276,8 @@ static esp_err_t _ledc_set_multi_fade(ledc_mode_t speed_mode, ledc_channel_t cha
        ledc_hal_set_duty_range_wr_addr(&(p_ledc_obj[speed_mode]->ledc_hal), channel, i);
    }
    ledc_hal_set_range_number(&(p_ledc_obj[speed_mode]->ledc_hal), channel, list_len);
+    // Clear left-off LEDC gamma ram registers, random data in ram could cause output waveform error
+    ledc_hal_clear_left_off_fade_param(&(p_ledc_obj[speed_mode]->ledc_hal), channel, list_len);
    portEXIT_CRITICAL(&ledc_spinlock);
    // Calculate target duty, and take account for overflow
    uint32_t target_duty = start_duty;
--- a/components/hal/include/hal/ledc_hal.h
+++ b/components/hal/include/hal/ledc_hal.h
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2019-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2019-2024 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */
@@ -386,6 +386,15 @@ void ledc_hal_get_range_number(ledc_hal_context_t *hal, ledc_channel_t channel_n
 * @return None
 */
 void ledc_hal_get_fade_param(ledc_hal_context_t *hal, ledc_channel_t channel_num, uint32_t range, uint32_t *dir, uint32_t *cycle, uint32_t *scale, uint32_t *step);
+
+/**
+ * @brief Clear left-off range fade parameters in LEDC gamma ram
+ *
+ * @param hal Context of the HAL layer
+ * @param channel_num LEDC channel index, select from ledc_channel_t
+ * @param start_range Start of the range to clear
+ */
+void ledc_hal_clear_left_off_fade_param(ledc_hal_context_t *hal, ledc_channel_t channel_num, uint32_t start_range);
 #endif //SOC_LEDC_GAMMA_CURVE_FADE_SUPPORTED

 /**
--- a/components/hal/ledc_hal_iram.c
+++ b/components/hal/ledc_hal_iram.c
@@ -1,11 +1,11 @@
 /*
- * SPDX-FileCopyrightText: 2019-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2019-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */

 // The HAL layer for LEDC (common part, in iram)
-// make these functions in a seperate file to make sure all LL functions are in the IRAM.
+// make these functions in a separate file to make sure all LL functions are in the IRAM.

 #include "esp_attr.h"
 #include "hal/ledc_hal.h"
@@ -70,6 +70,17 @@ void ledc_hal_get_range_number(ledc_hal_context_t *hal, ledc_channel_t channel_n
 {
    ledc_ll_get_range_number(hal->dev, hal->speed_mode, channel_num, range_num);
 }
+
+void ledc_hal_clear_left_off_fade_param(ledc_hal_context_t *hal, ledc_channel_t channel_num, uint32_t start_range)
+{
+    for (int i = start_range; i < SOC_LEDC_GAMMA_CURVE_FADE_RANGE_MAX; i++) {
+        ledc_ll_set_duty_direction(hal->dev, hal->speed_mode, channel_num, 0);
+        ledc_ll_set_duty_cycle(hal->dev, hal->speed_mode, channel_num, 0);
+        ledc_ll_set_duty_scale(hal->dev, hal->speed_mode, channel_num, 0);
+        ledc_ll_set_duty_num(hal->dev, hal->speed_mode, channel_num, 0);
+        ledc_ll_set_duty_range_wr_addr(hal->dev, hal->speed_mode, channel_num, i);
+    }
+}
 #endif //SOC_LEDC_GAMMA_CURVE_FADE_SUPPORTED

 void ledc_hal_get_fade_end_intr_status(ledc_hal_context_t *hal, uint32_t *intr_status)
--- a/docs/en/api-reference/peripherals/ledc.rst
+++ b/docs/en/api-reference/peripherals/ledc.rst
@@ -247,6 +247,10 @@ The range of the duty cycle values passed to functions depends on selected ``dut

        On {IDF_TARGET_NAME}, when channel's binded timer selects its maximum duty resolution, the duty cycle value cannot be set to ``(2 ** duty_resolution)``. Otherwise, the internal duty counter in the hardware will overflow and be messed up.

+    .. only:: esp32h2
+
+        The hardware limitation above only applies to chip revision before v1.2.
+

 Change PWM Duty Cycle using Hardware
 """"""""""""""""""""""""""""""""""""
--- a/docs/zh_CN/api-reference/peripherals/ledc.rst
+++ b/docs/zh_CN/api-reference/peripherals/ledc.rst
@@ -247,6 +247,10 @@ LED PWM 控制器可在无需 CPU 干预的情况下自动改变占空比，实

        在 {IDF_TARGET_NAME} 上，当通道绑定的定时器配置了其最大 PWM 占空比分辨率（ ``MAX_DUTY_RES`` ），通道的占空比不能被设置到 ``(2 ** MAX_DUTY_RES)`` 。否则，硬件内部占空比计数器会溢出，并导致占空比计算错误。

+    .. only:: esp32h2
+
+        以上硬件限制仅在芯片版本低于 v1.2 的 ESP32H2 上存在。
+

 使用硬件改变 PWM 占空比
 """"""""""""""""""""""""""""""""""""
--- a/examples/peripherals/ledc/ledc_basic/main/ledc_basic_example_main.c
+++ b/examples/peripherals/ledc/ledc_basic/main/ledc_basic_example_main.c
@@ -19,7 +19,7 @@
 #define LEDC_FREQUENCY          (5000) // Frequency in Hertz. Set frequency at 5 kHz

 /* Warning:
- * For ESP32, ESP32S2, ESP32S3, ESP32C3, ESP32C2, ESP32C6, ESP32H2 targets,
+ * For ESP32, ESP32S2, ESP32S3, ESP32C3, ESP32C2, ESP32C6, ESP32H2 (rev < 1.2) targets,
 * when LEDC_DUTY_RES selects the maximum duty resolution (i.e. value equal to SOC_LEDC_TIMER_BIT_WIDTH),
 * 100% duty cycle is not reachable (duty cannot be set to (2 ** SOC_LEDC_TIMER_BIT_WIDTH)).
 */