+/*
+ * Copyright © 2024 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include "ao.h"
+#include "ao_pwm.h"
+
+static uint8_t pwm_running;
+
+static uint16_t pwm_value[NUM_PWM];
+
+static void
+ao_pwm_up(void)
+{
+ if (pwm_running++ == 0) {
+ struct stm_tim234 *tim = &AO_PWM_TIMER;
+
+ tim->ccr1 = 0;
+ tim->ccr2 = 0;
+ tim->ccr3 = 0;
+ tim->ccr4 = 0;
+ tim->arr = PWM_MAX - 1; /* turn on the timer */
+ tim->cr1 = ((STM_TIM234_CR1_CKD_1 << STM_TIM234_CR1_CKD) |
+ (0 << STM_TIM234_CR1_ARPE) |
+ (STM_TIM234_CR1_CMS_EDGE << STM_TIM234_CR1_CMS) |
+ (STM_TIM234_CR1_DIR_UP << STM_TIM234_CR1_DIR) |
+ (0 << STM_TIM234_CR1_OPM) |
+ (0 << STM_TIM234_CR1_URS) |
+ (0 << STM_TIM234_CR1_UDIS) |
+ (1 << STM_TIM234_CR1_CEN));
+
+ /* Set the timer running */
+ tim->egr = (1 << STM_TIM234_EGR_UG);
+ }
+}
+
+static void
+ao_pwm_down(void)
+{
+ if (--pwm_running == 0) {
+ struct stm_tim234 *tim = &AO_PWM_TIMER;
+
+ tim->arr = 0;
+ tim->cr1 = ((STM_TIM234_CR1_CKD_1 << STM_TIM234_CR1_CKD) |
+ (0 << STM_TIM234_CR1_ARPE) |
+ (STM_TIM234_CR1_CMS_EDGE << STM_TIM234_CR1_CMS) |
+ (STM_TIM234_CR1_DIR_UP << STM_TIM234_CR1_DIR) |
+ (0 << STM_TIM234_CR1_OPM) |
+ (0 << STM_TIM234_CR1_URS) |
+ (0 << STM_TIM234_CR1_UDIS) |
+ (0 << STM_TIM234_CR1_CEN));
+
+ /* Stop the timer */
+ tim->egr = (1 << STM_TIM234_EGR_UG);
+ }
+}
+
+void
+ao_pwm_set(uint8_t pwm, uint16_t value)
+{
+ struct stm_tim234 *tim = &AO_PWM_TIMER;
+
+#if PWM_MAX < UINT16_MAX
+ if (value > PWM_MAX)
+ value = PWM_MAX;
+#endif
+ if (value != 0) {
+ if (pwm_value[pwm] == 0)
+ ao_pwm_up();
+ }
+ switch (pwm) {
+ case 0:
+ tim->ccr1 = value;
+ break;
+ case 1:
+ tim->ccr2 = value;
+ break;
+ case 2:
+ tim->ccr3 = value;
+ break;
+ case 3:
+ tim->ccr4 = value;
+ break;
+ }
+ if (value == 0) {
+ if (pwm_value[pwm] != 0)
+ ao_pwm_down();
+ }
+ pwm_value[pwm] = value;
+}
+
+static void
+ao_pwm_cmd(void)
+{
+ uint8_t ch;
+ uint16_t val;
+
+ ch = (uint8_t) ao_cmd_decimal();
+ val = (uint16_t) ao_cmd_decimal();
+ if (ao_cmd_status != ao_cmd_success)
+ return;
+
+ printf("Set channel %d to %d\n", ch, val);
+ ao_pwm_set(ch, val);
+}
+
+static const struct ao_cmds ao_pwm_cmds[] = {
+ { ao_pwm_cmd, "P <ch> <val>\0Set PWM ch to val" },
+ { 0, NULL },
+};
+
+void
+ao_pwm_init(void)
+{
+ struct stm_tim234 *tim = &AO_PWM_TIMER;
+
+ stm_rcc.apb1enr |= (1 << AO_PWM_TIMER_ENABLE);
+
+ tim->cr1 = 0;
+ tim->psc = AO_PWM_TIMER_SCALE - 1;
+ tim->cnt = 0;
+ tim->ccer = ((1 << STM_TIM234_CCER_CC1E) |
+ (0 << STM_TIM234_CCER_CC1P) |
+ (1 << STM_TIM234_CCER_CC2E) |
+ (0 << STM_TIM234_CCER_CC2P) |
+ (1 << STM_TIM234_CCER_CC3E) |
+ (0 << STM_TIM234_CCER_CC3P) |
+ (1 << STM_TIM234_CCER_CC4E) |
+ (0 << STM_TIM234_CCER_CC4P));
+
+ tim->ccmr1 = ((0 << STM_TIM234_CCMR1_OC2CE) |
+ (STM_TIM234_CCMR1_OC2M_PWM_MODE_1 << STM_TIM234_CCMR1_OC2M) |
+ (0 << STM_TIM234_CCMR1_OC2PE) |
+ (0 << STM_TIM234_CCMR1_OC2FE) |
+ (STM_TIM234_CCMR1_CC2S_OUTPUT << STM_TIM234_CCMR1_CC2S) |
+
+ (0 << STM_TIM234_CCMR1_OC1CE) |
+ (STM_TIM234_CCMR1_OC1M_PWM_MODE_1 << STM_TIM234_CCMR1_OC1M) |
+ (0 << STM_TIM234_CCMR1_OC1PE) |
+ (0 << STM_TIM234_CCMR1_OC1FE) |
+ (STM_TIM234_CCMR1_CC1S_OUTPUT << STM_TIM234_CCMR1_CC1S));
+
+
+ tim->ccmr2 = ((0 << STM_TIM234_CCMR2_OC4CE) |
+ (STM_TIM234_CCMR2_OC4M_PWM_MODE_1 << STM_TIM234_CCMR2_OC4M) |
+ (0 << STM_TIM234_CCMR2_OC4PE) |
+ (0 << STM_TIM234_CCMR2_OC4FE) |
+ (STM_TIM234_CCMR2_CC4S_OUTPUT << STM_TIM234_CCMR2_CC4S) |
+
+ (0 << STM_TIM234_CCMR2_OC3CE) |
+ (STM_TIM234_CCMR2_OC3M_PWM_MODE_1 << STM_TIM234_CCMR2_OC3M) |
+ (0 << STM_TIM234_CCMR2_OC3PE) |
+ (0 << STM_TIM234_CCMR2_OC3FE) |
+ (STM_TIM234_CCMR2_CC3S_OUTPUT << STM_TIM234_CCMR2_CC3S));
+ tim->egr = 0;
+
+ tim->sr = 0;
+ tim->dier = 0;
+ tim->smcr = 0;
+ tim->cr2 = ((0 << STM_TIM234_CR2_TI1S) |
+ (STM_TIM234_CR2_MMS_RESET<< STM_TIM234_CR2_MMS) |
+ (0 << STM_TIM234_CR2_CCDS));
+
+ stm_set_afio_mapr(AO_AFIO_PWM_REMAP,
+ AO_AFIO_PWM_REMAP_VAL,
+ AO_AFIO_PWM_REMAP_MASK);
+
+ ao_enable_port(AO_PWM_0_GPIO);
+
+ stm_gpio_conf(AO_PWM_0_GPIO, AO_PWM_0_PIN,
+ STM_GPIO_CR_MODE_OUTPUT_2MHZ,
+ STM_GPIO_CR_CNF_OUTPUT_AF_PUSH_PULL);
+#if NUM_PWM > 1
+ stm_gpio_conf(AO_PWM_1_GPIO, AO_PWM_1_PIN,
+ STM_GPIO_CR_MODE_OUTPUT_2MHZ,
+ STM_GPIO_CR_CNF_OUTPUT_AF_PUSH_PULL);
+#endif
+#if NUM_PWM > 2
+ stm_gpio_conf(AO_PWM_2_GPIO, AO_PWM_2_PIN,
+ STM_GPIO_CR_MODE_OUTPUT_2MHZ,
+ STM_GPIO_CR_CNF_OUTPUT_AF_PUSH_PULL);
+#endif
+#if NUM_PWM > 3
+ stm_gpio_conf(AO_PWM_3_GPIO, AO_PWM_3_PIN,
+ STM_GPIO_CR_MODE_OUTPUT_2MHZ,
+ STM_GPIO_CR_CNF_OUTPUT_AF_PUSH_PULL);
+#endif
+ ao_cmd_register(&ao_pwm_cmds[0]);
+}