/**************************************************************************** * arch/arm/src/kl/kl_pwm.c * * Copyright (C) 2013, 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * Alan Carvalho de Assis * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include "up_internal.h" #include "up_arch.h" #include "chip.h" #include "kl_pwm.h" #include "kl_gpio.h" #include "chip/kl_tpm.h" #include "chip/kl_sim.h" /* This module then only compiles if there is at least one enabled timer * intended for use with the PWM upper half driver. */ #if defined(CONFIG_KL_TPM0_PWM) || defined(CONFIG_KL_TPM1_PWM) || \ defined(CONFIG_KL_TPM2_PWM) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* PWM/Timer Definitions ****************************************************/ /* Debug ********************************************************************/ #ifdef CONFIG_DEBUG_PWM_INFO # define pwm_dumpgpio(p,m) kl_dumpgpio(p,m) #else # define pwm_dumpgpio(p,m) #endif /**************************************************************************** * Private Types ****************************************************************************/ /* This structure represents the state of one PWM timer */ struct kl_pwmtimer_s { FAR const struct pwm_ops_s *ops; /* PWM operations */ uint8_t tpmid; /* Timer/PWM Module ID {0,..,2} */ uint8_t channel; /* Timer/PWM Module channel: {0,..5} */ uint32_t base; /* The base address of the timer */ uint32_t pincfg; /* Output pin configuration */ uint32_t pclk; /* The frequency of the peripheral clock */ }; /**************************************************************************** * Static Function Prototypes ****************************************************************************/ /* Register access */ static uint32_t pwm_getreg(struct kl_pwmtimer_s *priv, int offset); static void pwm_putreg(struct kl_pwmtimer_s *priv, int offset, uint32_t value); #ifdef CONFIG_DEBUG_PWM_INFO static void pwm_dumpregs(struct kl_pwmtimer_s *priv, FAR const char *msg); #else # define pwm_dumpregs(priv,msg) #endif /* Timer management */ static int pwm_timer(FAR struct kl_pwmtimer_s *priv, FAR const struct pwm_info_s *info); /* PWM driver methods */ static int pwm_setup(FAR struct pwm_lowerhalf_s *dev); static int pwm_shutdown(FAR struct pwm_lowerhalf_s *dev); static int pwm_start(FAR struct pwm_lowerhalf_s *dev, FAR const struct pwm_info_s *info); static int pwm_stop(FAR struct pwm_lowerhalf_s *dev); static int pwm_ioctl(FAR struct pwm_lowerhalf_s *dev, int cmd, unsigned long arg); /**************************************************************************** * Private Data ****************************************************************************/ /* This is the list of lower half PWM driver methods used by the upper half driver */ static const struct pwm_ops_s g_pwmops = { .setup = pwm_setup, .shutdown = pwm_shutdown, .start = pwm_start, .stop = pwm_stop, .ioctl = pwm_ioctl, }; #ifdef CONFIG_KL_TPM0_PWM static struct kl_pwmtimer_s g_pwm0dev = { .ops = &g_pwmops, .tpmid = 0, .channel = CONFIG_KL_TPM0_CHANNEL, .base = KL_TPM0_BASE, .pincfg = PWM_TPM0_PINCFG, .pclk = BOARD_CORECLK_FREQ, }; #endif #ifdef CONFIG_KL_TPM1_PWM static struct kl_pwmtimer_s g_pwm1dev = { .ops = &g_pwmops, .tpmid = 1, .channel = CONFIG_KL_TPM1_CHANNEL, .base = KL_TPM1_BASE, .pincfg = PWM_TPM1_PINCFG, .pclk = BOARD_CORECLK_FREQ, }; #endif #ifdef CONFIG_KL_TPM2_PWM static struct kl_pwmtimer_s g_pwm2dev = { .ops = &g_pwmops, .tpmid = 2, .channel = CONFIG_KL_TPM2_CHANNEL, .base = KL_TPM2_BASE, .pincfg = PWM_TPM2_PINCFG, .pclk = BOARD_CORECLK_FREQ, }; #endif /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: pwm_getreg * * Description: * Read the value of an PWM timer register. * * Input Parameters: * priv - A reference to the PWM block status * offset - The offset to the register to read * * Returned Value: * The current contents of the specified register * ****************************************************************************/ static uint32_t pwm_getreg(struct kl_pwmtimer_s *priv, int offset) { return getreg32(priv->base + offset); } /**************************************************************************** * Name: pwm_putreg * * Description: * Read the value of an PWM timer register. * * Input Parameters: * priv - A reference to the PWM block status * offset - The offset to the register to read * * Returned Value: * None * ****************************************************************************/ static void pwm_putreg(struct kl_pwmtimer_s *priv, int offset, uint32_t value) { putreg32(value, priv->base + offset); } /**************************************************************************** * Name: pwm_dumpregs * * Description: * Dump all timer registers. * * Input parameters: * priv - A reference to the PWM block status * * Returned Value: * None * ****************************************************************************/ #ifdef CONFIG_DEBUG_PWM_INFO static void pwm_dumpregs(struct kl_pwmtimer_s *priv, FAR const char *msg) { int nchannels = (priv->tpmid == 0) ? 6 : 2; pwminfo("%s:\n", msg); pwminfo(" TPM%d_SC: %04x TPM%d_CNT: %04x TPM%d_MOD: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_CNT_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_MOD_OFFSET)); pwminfo(" TPM%d_STATUS: %04x TPM%d_CONF: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_STATUS_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_CONF_OFFSET)); pwminfo(" TPM%d_C0SC: %04x TPM%d_C0V: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_C0SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_C0V_OFFSET)); pwminfo(" TPM%d_C1SC: %04x TPM%d_C1V: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_C1SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_C1V_OFFSET)); if (nchannels >= 3) { pwminfo(" TPM%d_C2SC: %04x TPM%d_C2V: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_C2SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_C2V_OFFSET)); } if (nchannels >= 4) { pwminfo(" TPM%d_C3SC: %04x TPM%d_C3V: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_C3SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_C3V_OFFSET)); } if (nchannels >= 5) { pwminfo(" TPM%d_C4SC: %04x TPM%d_C4V: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_C4SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_C4V_OFFSET)); } if (nchannels >= 6) { pwminfo(" TPM%d_C5SC: %04x TPM%d_C5V: %04x\n", priv->tpmid, pwm_getreg(priv, TPM_C5SC_OFFSET), priv->tpmid, pwm_getreg(priv, TPM_C5V_OFFSET)); } } #endif /**************************************************************************** * Name: pwm_timer * * Description: * (Re-)initialize the timer resources and start the pulsed output * * Input parameters: * priv - A reference to the lower half PWM driver state structure * info - A reference to the characteristics of the pulsed output * * Returned Value: * Zero on success; a negated errno value on failure * ****************************************************************************/ static int pwm_timer(FAR struct kl_pwmtimer_s *priv, FAR const struct pwm_info_s *info) { /* Calculated values */ uint32_t prescaler; uint32_t tpmclk; uint32_t modulo; uint32_t regval; uint32_t cv; uint8_t i; static const uint8_t presc_values[8] = {1, 2, 4, 8, 16, 32, 64, 128}; /* Register contents */ DEBUGASSERT(priv != NULL && info != NULL); pwminfo("TPM%d channel: %d frequency: %d duty: %08x\n", priv->tpmid, priv->channel, info->frequency, info->duty); DEBUGASSERT(info->frequency > 0 && info->duty > 0 && info->duty < uitoub16(100)); /* Calculate optimal values for the timer prescaler and for the timer modulo * register. If' frequency' is the desired frequency, then * * modulo = tpmclk / frequency * tpmclk = pclk / presc * * Or, * * modulo = pclk / presc / frequency * * There are many solutions to do this, but the best solution will be the * one that has the largest modulo value and the smallest prescaler value. * That is the solution that should give us the most accuracy in the timer * control. Subject to: * * 1 <= presc <= 128 (need to be 1, 2, 4, 8, 16, 32, 64, 128) * 1 <= modulo <= 65535 * * So presc = pclk / 65535 / frequency would be optimal. * * Example: * * pclk = 24 MHz * frequency = 100 Hz * * prescaler = 24,000,000 / 65,535 / 100 * = 3.6 (or 4 -- taking the ceiling always) * timclk = 24,000,000 / 4 * = 6,000,000 * modulo = 6,000,000 / 100 * = 60,000 */ prescaler = (priv->pclk / info->frequency + 65534) / 65535; for (i = 0; i < 7; i++) { if (prescaler <= presc_values[i]) { break; } } prescaler = i; tpmclk = priv->pclk / presc_values[prescaler]; modulo = tpmclk / info->frequency; if (modulo < 1) { modulo = 1; } else if (modulo > 65535) { modulo = 65535; } /* Duty cycle: * * duty cycle = cv / modulo (fractional value) */ cv = b16toi(info->duty * modulo + b16HALF); pwminfo("TPM%d PCLK: %d frequency: %d TPMCLK: %d prescaler: %d modulo: %d c0v: %d\n", priv->tpmid, priv->pclk, info->frequency, tpmclk, presc_values[prescaler], modulo, cv); /* Disable TPM and reset CNT before writing MOD and PS */ pwm_putreg(priv, TPM_SC_OFFSET, TPM_SC_CMOD_DIS); pwm_putreg(priv, TPM_CNT_OFFSET, 0); /* Set the modulo value */ pwm_putreg(priv, TPM_MOD_OFFSET, (uint16_t)modulo); /* Set the duty cycle for channel specific */ switch (priv->channel) { case 0: /* PWM Mode configuration: Channel 0 */ { pwm_putreg(priv, TPM_C0SC_OFFSET, TPM_CnSC_MSB | TPM_CnSC_ELSB); pwm_putreg(priv, TPM_C0V_OFFSET, (uint16_t) cv); } break; case 1: /* PWM Mode configuration: Channel 1 */ { pwm_putreg(priv, TPM_C1SC_OFFSET, TPM_CnSC_MSB | TPM_CnSC_ELSB); pwm_putreg(priv, TPM_C1V_OFFSET, (uint16_t) cv); } break; case 2: /* PWM Mode configuration: Channel 2 */ { pwm_putreg(priv, TPM_C2SC_OFFSET, TPM_CnSC_MSB | TPM_CnSC_ELSB); pwm_putreg(priv, TPM_C2V_OFFSET, (uint16_t) cv); } break; case 3: /* PWM Mode configuration: Channel 3 */ { pwm_putreg(priv, TPM_C3SC_OFFSET, TPM_CnSC_MSB | TPM_CnSC_ELSB); pwm_putreg(priv, TPM_C3V_OFFSET, (uint16_t) cv); } break; case 4: /* PWM Mode configuration: Channel 4 */ { pwm_putreg(priv, TPM_C4SC_OFFSET, TPM_CnSC_MSB | TPM_CnSC_ELSB); pwm_putreg(priv, TPM_C4V_OFFSET, (uint16_t) cv); } break; case 5: /* PWM Mode configuration: Channel 5 */ { pwm_putreg(priv, TPM_C5SC_OFFSET, TPM_CnSC_MSB | TPM_CnSC_ELSB); pwm_putreg(priv, TPM_C5V_OFFSET, (uint16_t) cv); } break; default: pwmerr("ERROR: No such channel: %d\n", priv->channel); return -EINVAL; } /* Set prescaler and enable clock */ regval = pwm_getreg(priv, TPM_SC_OFFSET); regval &= ~(TPM_SC_PS_MASK); regval &= ~(TPM_SC_CMOD_MASK); regval |= prescaler | TPM_SC_CMOD_LPTPM_CLK; pwm_putreg(priv, TPM_SC_OFFSET, (uint16_t)regval); pwm_dumpregs(priv, "After starting"); return OK; } /**************************************************************************** * Name: pwm_setup * * Description: * This method is called when the driver is opened. The lower half driver * should configure and initialize the device so that it is ready for use. * It should not, however, output pulses until the start method is called. * * Input parameters: * dev - A reference to the lower half PWM driver state structure * * Returned Value: * Zero on success; a negated errno value on failure * * Assumptions: * AHB1 or 2 clocking for the GPIOs and timer has already been configured * by the RCC logic at power up. * ****************************************************************************/ static int pwm_setup(FAR struct pwm_lowerhalf_s *dev) { uint32_t regval; FAR struct kl_pwmtimer_s *priv = (FAR struct kl_pwmtimer_s *)dev; /* Enable access to TPM modules */ regval = getreg32(KL_SIM_SCGC6); regval |= SIM_SCGC6_TPM0 | SIM_SCGC6_TPM1 | SIM_SCGC6_TPM2; putreg32(regval, KL_SIM_SCGC6); pwminfo("TPM%d pincfg: %08x\n", priv->tpmid, priv->pincfg); pwm_dumpregs(priv, "Initially"); /* Configure the PWM output pin, but do not start the timer yet */ kl_configgpio(priv->pincfg); pwm_dumpgpio(priv->pincfg, "PWM setup"); return OK; } /**************************************************************************** * Name: pwm_shutdown * * Description: * This method is called when the driver is closed. The lower half driver * stop pulsed output, free any resources, disable the timer hardware, and * put the system into the lowest possible power usage state * * Input parameters: * dev - A reference to the lower half PWM driver state structure * * Returned Value: * Zero on success; a negated errno value on failure * ****************************************************************************/ static int pwm_shutdown(FAR struct pwm_lowerhalf_s *dev) { FAR struct kl_pwmtimer_s *priv = (FAR struct kl_pwmtimer_s *)dev; uint32_t pincfg; pwminfo("TPM%d pincfg: %08x\n", priv->tpmid, priv->pincfg); /* Make sure that the output has been stopped */ pwm_stop(dev); /* Then put the GPIO pin back to the default state */ pincfg = (priv->pincfg & ~(_PIN_MODE_MASK)); pincfg |= GPIO_INPUT; kl_configgpio(pincfg); return OK; } /**************************************************************************** * Name: pwm_start * * Description: * (Re-)initialize the timer resources and start the pulsed output * * Input parameters: * dev - A reference to the lower half PWM driver state structure * info - A reference to the characteristics of the pulsed output * * Returned Value: * Zero on success; a negated errno value on failure * ****************************************************************************/ static int pwm_start(FAR struct pwm_lowerhalf_s *dev, FAR const struct pwm_info_s *info) { FAR struct kl_pwmtimer_s *priv = (FAR struct kl_pwmtimer_s *)dev; return pwm_timer(priv, info); } /**************************************************************************** * Name: pwm_stop * * Description: * Stop the pulsed output and reset the timer resources * * Input parameters: * dev - A reference to the lower half PWM driver state structure * * Returned Value: * Zero on success; a negated errno value on failure * * Assumptions: * This function is called to stop the pulsed output at anytime. This * method is also called from the timer interrupt handler when a repetition * count expires... automatically stopping the timer. * ****************************************************************************/ static int pwm_stop(FAR struct pwm_lowerhalf_s *dev) { FAR struct kl_pwmtimer_s *priv = (FAR struct kl_pwmtimer_s *)dev; irqstate_t flags; pwminfo("TPM%d\n", priv->tpmid); /* Disable interrupts momentary to stop any ongoing timer processing and * to prevent any concurrent access to the reset register. */ flags = enter_critical_section(); /* Disable further interrupts and stop the timer */ pwm_putreg(priv, TPM_SC_OFFSET, TPM_SC_CMOD_DIS); pwm_putreg(priv, TPM_CNT_OFFSET, 0); /* Determine which timer channel to clear */ switch (priv->channel) { case 0: pwm_putreg(priv, TPM_C0V_OFFSET, 0); break; case 1: pwm_putreg(priv, TPM_C1V_OFFSET, 0); break; case 2: pwm_putreg(priv, TPM_C2V_OFFSET, 0); break; case 3: pwm_putreg(priv, TPM_C3V_OFFSET, 0); break; case 4: pwm_putreg(priv, TPM_C4V_OFFSET, 0); break; case 5: pwm_putreg(priv, TPM_C5V_OFFSET, 0); break; default: pwmerr("ERROR: No such channel: %d\n", priv->channel); return -EINVAL; } leave_critical_section(flags); pwm_dumpregs(priv, "After stop"); return OK; } /**************************************************************************** * Name: pwm_ioctl * * Description: * Lower-half logic may support platform-specific ioctl commands * * Input parameters: * dev - A reference to the lower half PWM driver state structure * cmd - The ioctl command * arg - The argument accompanying the ioctl command * * Returned Value: * Zero on success; a negated errno value on failure * ****************************************************************************/ static int pwm_ioctl(FAR struct pwm_lowerhalf_s *dev, int cmd, unsigned long arg) { #ifdef CONFIG_DEBUG_PWM_INFO FAR struct kl_pwmtimer_s *priv = (FAR struct kl_pwmtimer_s *)dev; /* There are no platform-specific ioctl commands */ pwminfo("TPM%d\n", priv->tpmid); #endif return -ENOTTY; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: kl_pwminitialize * * Description: * Initialize one timer for use with the upper_level PWM driver. * * Input Parameters: * timer - A number identifying the timer use. * * Returned Value: * On success, a pointer to the KL lower half PWM driver is returned. * NULL is returned on any failure. * ****************************************************************************/ FAR struct pwm_lowerhalf_s *kl_pwminitialize(int timer) { FAR struct kl_pwmtimer_s *lower; pwminfo("TPM%d\n", timer); switch (timer) { #ifdef CONFIG_KL_TPM0_PWM case 0: lower = &g_pwm0dev; break; #endif #ifdef CONFIG_KL_TPM1_PWM case 1: lower = &g_pwm1dev; break; #endif #ifdef CONFIG_KL_TPM2_PWM case 2: lower = &g_pwm2dev; break; #endif default: pwmerr("ERROR: No such timer configured\n"); return NULL; } return (FAR struct pwm_lowerhalf_s *)lower; } #endif /* CONFIG_KL_TPMn_PWM, n = 0,...,2 */