forked from mirrors/linux
		
	pwm: stm32: Implementation of the waveform callbacks
Convert the stm32 pwm driver to use the new callbacks for hardware programming. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/332d4f736d8360038d03f109c013441c655eea23.1726819463.git.u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
This commit is contained in:
		
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					 1 changed files with 391 additions and 221 deletions
				
			
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					@ -51,6 +51,391 @@ static u32 active_channels(struct stm32_pwm *dev)
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	return ccer & TIM_CCER_CCXE;
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						return ccer & TIM_CCER_CCXE;
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}
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					}
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					struct stm32_pwm_waveform {
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						u32 ccer;
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						u32 psc;
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						u32 arr;
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						u32 ccr;
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					};
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					static int stm32_pwm_round_waveform_tohw(struct pwm_chip *chip,
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										 struct pwm_device *pwm,
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										 const struct pwm_waveform *wf,
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										 void *_wfhw)
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					{
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						struct stm32_pwm_waveform *wfhw = _wfhw;
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						struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
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						unsigned int ch = pwm->hwpwm;
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						unsigned long rate;
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						u64 ccr, duty;
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						int ret;
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						if (wf->period_length_ns == 0) {
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							*wfhw = (struct stm32_pwm_waveform){
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								.ccer = 0,
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							};
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							return 0;
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						}
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						ret = clk_enable(priv->clk);
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						if (ret)
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							return ret;
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						wfhw->ccer = TIM_CCER_CCxE(ch + 1);
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						if (priv->have_complementary_output)
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							wfhw->ccer = TIM_CCER_CCxNE(ch + 1);
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						rate = clk_get_rate(priv->clk);
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						if (active_channels(priv) & ~(1 << ch * 4)) {
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							u64 arr;
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							/*
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							 * Other channels are already enabled, so the configured PSC and
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							 * ARR must be used for this channel, too.
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							 */
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							ret = regmap_read(priv->regmap, TIM_PSC, &wfhw->psc);
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							if (ret)
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								goto out;
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							ret = regmap_read(priv->regmap, TIM_ARR, &wfhw->arr);
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							if (ret)
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								goto out;
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							/*
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							 * calculate the best value for ARR for the given PSC, refuse if
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							 * the resulting period gets bigger than the requested one.
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							 */
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							arr = mul_u64_u64_div_u64(wf->period_length_ns, rate,
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										  (u64)NSEC_PER_SEC * (wfhw->psc + 1));
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							if (arr <= wfhw->arr) {
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								/*
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								 * requested period is small than the currently
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								 * configured and unchangable period, report back the smallest
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								 * possible period, i.e. the current state; Initialize
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								 * ccr to anything valid.
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								 */
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								wfhw->ccr = 0;
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								ret = 1;
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								goto out;
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							}
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						} else {
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							/*
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							 * .probe() asserted that clk_get_rate() is not bigger than 1 GHz, so
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							 * the calculations here won't overflow.
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							 * First we need to find the minimal value for prescaler such that
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							 *
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							 *        period_ns * clkrate
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							 *   ------------------------------ < max_arr + 1
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							 *   NSEC_PER_SEC * (prescaler + 1)
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							 *
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							 * This equation is equivalent to
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							 *
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							 *        period_ns * clkrate
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							 *   ---------------------------- < prescaler + 1
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							 *   NSEC_PER_SEC * (max_arr + 1)
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							 *
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							 * Using integer division and knowing that the right hand side is
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							 * integer, this is further equivalent to
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							 *
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							 *   (period_ns * clkrate) // (NSEC_PER_SEC * (max_arr + 1)) ≤ prescaler
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							 */
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							u64 psc = mul_u64_u64_div_u64(wf->period_length_ns, rate,
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										      (u64)NSEC_PER_SEC * ((u64)priv->max_arr + 1));
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							u64 arr;
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							wfhw->psc = min_t(u64, psc, MAX_TIM_PSC);
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							arr = mul_u64_u64_div_u64(wf->period_length_ns, rate,
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										  (u64)NSEC_PER_SEC * (wfhw->psc + 1));
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							if (!arr) {
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								/*
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								 * requested period is too small, report back the smallest
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								 * possible period, i.e. ARR = 0. The only valid CCR
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								 * value is then zero, too.
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								 */
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								wfhw->arr = 0;
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								wfhw->ccr = 0;
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								ret = 1;
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								goto out;
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							}
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							/*
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							 * ARR is limited intentionally to values less than
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							 * priv->max_arr to allow 100% duty cycle.
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							 */
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							wfhw->arr = min_t(u64, arr, priv->max_arr) - 1;
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						}
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						duty = mul_u64_u64_div_u64(wf->duty_length_ns, rate,
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									   (u64)NSEC_PER_SEC * (wfhw->psc + 1));
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						duty = min_t(u64, duty, wfhw->arr + 1);
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						if (wf->duty_length_ns && wf->duty_offset_ns &&
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						    wf->duty_length_ns + wf->duty_offset_ns >= wf->period_length_ns) {
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							wfhw->ccer |= TIM_CCER_CCxP(ch + 1);
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							if (priv->have_complementary_output)
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								wfhw->ccer |= TIM_CCER_CCxNP(ch + 1);
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							ccr = wfhw->arr + 1 - duty;
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						} else {
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							ccr = duty;
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						}
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						wfhw->ccr = min_t(u64, ccr, wfhw->arr + 1);
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						dev_dbg(&chip->dev, "pwm#%u: %lld/%lld [+%lld] @%lu -> CCER: %08x, PSC: %08x, ARR: %08x, CCR: %08x\n",
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							pwm->hwpwm, wf->duty_length_ns, wf->period_length_ns, wf->duty_offset_ns,
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							rate, wfhw->ccer, wfhw->psc, wfhw->arr, wfhw->ccr);
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					out:
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						clk_disable(priv->clk);
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						return ret;
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					}
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					/*
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					 * This should be moved to lib/math/div64.c. Currently there are some changes
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					 * pending to mul_u64_u64_div_u64. Uwe will care for that when the dust settles.
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					 */
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					static u64 stm32_pwm_mul_u64_u64_div_u64_roundup(u64 a, u64 b, u64 c)
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					{
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						u64 res = mul_u64_u64_div_u64(a, b, c);
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						/* Those multiplications might overflow but it doesn't matter */
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						u64 rem = a * b - c * res;
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						if (rem)
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							res += 1;
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						return res;
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					}
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					static int stm32_pwm_round_waveform_fromhw(struct pwm_chip *chip,
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										   struct pwm_device *pwm,
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										   const void *_wfhw,
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										   struct pwm_waveform *wf)
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					{
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						const struct stm32_pwm_waveform *wfhw = _wfhw;
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						struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
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						unsigned int ch = pwm->hwpwm;
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						if (wfhw->ccer & TIM_CCER_CCxE(ch + 1)) {
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							unsigned long rate = clk_get_rate(priv->clk);
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							u64 ccr_ns;
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							/* The result doesn't overflow for rate >= 15259 */
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							wf->period_length_ns = stm32_pwm_mul_u64_u64_div_u64_roundup(((u64)wfhw->psc + 1) * (wfhw->arr + 1),
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														     NSEC_PER_SEC, rate);
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							ccr_ns = stm32_pwm_mul_u64_u64_div_u64_roundup(((u64)wfhw->psc + 1) * wfhw->ccr,
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												       NSEC_PER_SEC, rate);
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							if (wfhw->ccer & TIM_CCER_CCxP(ch + 1)) {
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								wf->duty_length_ns =
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									stm32_pwm_mul_u64_u64_div_u64_roundup(((u64)wfhw->psc + 1) * (wfhw->arr + 1 - wfhw->ccr),
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													      NSEC_PER_SEC, rate);
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								wf->duty_offset_ns = ccr_ns;
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							} else {
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								wf->duty_length_ns = ccr_ns;
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								wf->duty_offset_ns = 0;
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							}
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							dev_dbg(&chip->dev, "pwm#%u: CCER: %08x, PSC: %08x, ARR: %08x, CCR: %08x @%lu -> %lld/%lld [+%lld]\n",
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								pwm->hwpwm, wfhw->ccer, wfhw->psc, wfhw->arr, wfhw->ccr, rate,
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								wf->duty_length_ns, wf->period_length_ns, wf->duty_offset_ns);
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						} else {
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							*wf = (struct pwm_waveform){
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								.period_length_ns = 0,
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							};
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						}
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						return 0;
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					}
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					static int stm32_pwm_read_waveform(struct pwm_chip *chip,
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									     struct pwm_device *pwm,
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									     void *_wfhw)
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					{
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						struct stm32_pwm_waveform *wfhw = _wfhw;
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						struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
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						unsigned int ch = pwm->hwpwm;
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						int ret;
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						ret = clk_enable(priv->clk);
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						if (ret)
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							return ret;
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						ret = regmap_read(priv->regmap, TIM_CCER, &wfhw->ccer);
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						if (ret)
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							goto out;
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						if (wfhw->ccer & TIM_CCER_CCxE(ch + 1)) {
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							ret = regmap_read(priv->regmap, TIM_PSC, &wfhw->psc);
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							if (ret)
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								goto out;
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							ret = regmap_read(priv->regmap, TIM_ARR, &wfhw->arr);
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							if (ret)
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								goto out;
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							if (wfhw->arr == U32_MAX)
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								wfhw->arr -= 1;
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							ret = regmap_read(priv->regmap, TIM_CCRx(ch + 1), &wfhw->ccr);
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							if (ret)
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								goto out;
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							if (wfhw->ccr > wfhw->arr + 1)
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								wfhw->ccr = wfhw->arr + 1;
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						}
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					out:
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						clk_disable(priv->clk);
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						return ret;
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					}
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					static int stm32_pwm_write_waveform(struct pwm_chip *chip,
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									      struct pwm_device *pwm,
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									      const void *_wfhw)
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					{
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						const struct stm32_pwm_waveform *wfhw = _wfhw;
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						struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
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						unsigned int ch = pwm->hwpwm;
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						int ret;
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						ret = clk_enable(priv->clk);
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						if (ret)
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							return ret;
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						if (wfhw->ccer & TIM_CCER_CCxE(ch + 1)) {
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							u32 ccer, mask;
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							unsigned int shift;
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							u32 ccmr;
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							ret = regmap_read(priv->regmap, TIM_CCER, &ccer);
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							if (ret)
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								goto out;
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							/* If there are other channels enabled, don't update PSC and ARR */
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							if (ccer & ~TIM_CCER_CCxE(ch + 1) & TIM_CCER_CCXE) {
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								u32 psc, arr;
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								ret = regmap_read(priv->regmap, TIM_PSC, &psc);
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								if (ret)
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									goto out;
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								if (psc != wfhw->psc) {
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									ret = -EBUSY;
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 | 
									goto out;
 | 
				
			||||||
 | 
								}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								regmap_read(priv->regmap, TIM_ARR, &arr);
 | 
				
			||||||
 | 
								if (ret)
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								if (arr != wfhw->arr) {
 | 
				
			||||||
 | 
									ret = -EBUSY;
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
								}
 | 
				
			||||||
 | 
							} else {
 | 
				
			||||||
 | 
								ret = regmap_write(priv->regmap, TIM_PSC, wfhw->psc);
 | 
				
			||||||
 | 
								if (ret)
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								ret = regmap_write(priv->regmap, TIM_ARR, wfhw->arr);
 | 
				
			||||||
 | 
								if (ret)
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								ret = regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE);
 | 
				
			||||||
 | 
								if (ret)
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							/* set polarity */
 | 
				
			||||||
 | 
							mask = TIM_CCER_CCxP(ch + 1) | TIM_CCER_CCxNP(ch + 1);
 | 
				
			||||||
 | 
							ret = regmap_update_bits(priv->regmap, TIM_CCER, mask, wfhw->ccer);
 | 
				
			||||||
 | 
							if (ret)
 | 
				
			||||||
 | 
								goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							ret = regmap_write(priv->regmap, TIM_CCRx(ch + 1), wfhw->ccr);
 | 
				
			||||||
 | 
							if (ret)
 | 
				
			||||||
 | 
								goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							/* Configure output mode */
 | 
				
			||||||
 | 
							shift = (ch & 0x1) * CCMR_CHANNEL_SHIFT;
 | 
				
			||||||
 | 
							ccmr = (TIM_CCMR_PE | TIM_CCMR_M1) << shift;
 | 
				
			||||||
 | 
							mask = CCMR_CHANNEL_MASK << shift;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							if (ch < 2)
 | 
				
			||||||
 | 
								ret = regmap_update_bits(priv->regmap, TIM_CCMR1, mask, ccmr);
 | 
				
			||||||
 | 
							else
 | 
				
			||||||
 | 
								ret = regmap_update_bits(priv->regmap, TIM_CCMR2, mask, ccmr);
 | 
				
			||||||
 | 
							if (ret)
 | 
				
			||||||
 | 
								goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							ret = regmap_set_bits(priv->regmap, TIM_BDTR, TIM_BDTR_MOE);
 | 
				
			||||||
 | 
							if (ret)
 | 
				
			||||||
 | 
								goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							if (!(ccer & TIM_CCER_CCxE(ch + 1))) {
 | 
				
			||||||
 | 
								mask = TIM_CCER_CCxE(ch + 1) | TIM_CCER_CCxNE(ch + 1);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								ret = clk_enable(priv->clk);
 | 
				
			||||||
 | 
								if (ret)
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								ccer = (ccer & ~mask) | (wfhw->ccer & mask);
 | 
				
			||||||
 | 
								regmap_write(priv->regmap, TIM_CCER, ccer);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								/* Make sure that registers are updated */
 | 
				
			||||||
 | 
								regmap_set_bits(priv->regmap, TIM_EGR, TIM_EGR_UG);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								/* Enable controller */
 | 
				
			||||||
 | 
								regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
 | 
				
			||||||
 | 
							}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						} else {
 | 
				
			||||||
 | 
							/* disable channel */
 | 
				
			||||||
 | 
							u32 mask, ccer;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							mask = TIM_CCER_CCxE(ch + 1);
 | 
				
			||||||
 | 
							if (priv->have_complementary_output)
 | 
				
			||||||
 | 
								mask |= TIM_CCER_CCxNE(ch + 1);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							ret = regmap_read(priv->regmap, TIM_CCER, &ccer);
 | 
				
			||||||
 | 
							if (ret)
 | 
				
			||||||
 | 
								goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							if (ccer & mask) {
 | 
				
			||||||
 | 
								ccer = ccer & ~mask;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								ret = regmap_write(priv->regmap, TIM_CCER, ccer);
 | 
				
			||||||
 | 
								if (ret)
 | 
				
			||||||
 | 
									goto out;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								if (!(ccer & TIM_CCER_CCXE)) {
 | 
				
			||||||
 | 
									/* When all channels are disabled, we can disable the controller */
 | 
				
			||||||
 | 
									ret = regmap_clear_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
 | 
				
			||||||
 | 
									if (ret)
 | 
				
			||||||
 | 
										goto out;
 | 
				
			||||||
 | 
								}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								clk_disable(priv->clk);
 | 
				
			||||||
 | 
							}
 | 
				
			||||||
 | 
						}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					out:
 | 
				
			||||||
 | 
						clk_disable(priv->clk);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return ret;
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
#define TIM_CCER_CC12P (TIM_CCER_CC1P | TIM_CCER_CC2P)
 | 
					#define TIM_CCER_CC12P (TIM_CCER_CC1P | TIM_CCER_CC2P)
 | 
				
			||||||
#define TIM_CCER_CC12E (TIM_CCER_CC1E | TIM_CCER_CC2E)
 | 
					#define TIM_CCER_CC12E (TIM_CCER_CC1E | TIM_CCER_CC2E)
 | 
				
			||||||
#define TIM_CCER_CC34P (TIM_CCER_CC3P | TIM_CCER_CC4P)
 | 
					#define TIM_CCER_CC34P (TIM_CCER_CC3P | TIM_CCER_CC4P)
 | 
				
			||||||
| 
						 | 
					@ -308,228 +693,13 @@ static int stm32_pwm_capture(struct pwm_chip *chip, struct pwm_device *pwm,
 | 
				
			||||||
	return ret;
 | 
						return ret;
 | 
				
			||||||
}
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
static int stm32_pwm_config(struct stm32_pwm *priv, unsigned int ch,
 | 
					 | 
				
			||||||
			    u64 duty_ns, u64 period_ns)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	unsigned long long prd, dty;
 | 
					 | 
				
			||||||
	unsigned long long prescaler;
 | 
					 | 
				
			||||||
	u32 ccmr, mask, shift;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/*
 | 
					 | 
				
			||||||
	 * .probe() asserted that clk_get_rate() is not bigger than 1 GHz, so
 | 
					 | 
				
			||||||
	 * the calculations here won't overflow.
 | 
					 | 
				
			||||||
	 * First we need to find the minimal value for prescaler such that
 | 
					 | 
				
			||||||
	 *
 | 
					 | 
				
			||||||
	 *        period_ns * clkrate
 | 
					 | 
				
			||||||
	 *   ------------------------------ < max_arr + 1
 | 
					 | 
				
			||||||
	 *   NSEC_PER_SEC * (prescaler + 1)
 | 
					 | 
				
			||||||
	 *
 | 
					 | 
				
			||||||
	 * This equation is equivalent to
 | 
					 | 
				
			||||||
	 *
 | 
					 | 
				
			||||||
	 *        period_ns * clkrate
 | 
					 | 
				
			||||||
	 *   ---------------------------- < prescaler + 1
 | 
					 | 
				
			||||||
	 *   NSEC_PER_SEC * (max_arr + 1)
 | 
					 | 
				
			||||||
	 *
 | 
					 | 
				
			||||||
	 * Using integer division and knowing that the right hand side is
 | 
					 | 
				
			||||||
	 * integer, this is further equivalent to
 | 
					 | 
				
			||||||
	 *
 | 
					 | 
				
			||||||
	 *   (period_ns * clkrate) // (NSEC_PER_SEC * (max_arr + 1)) ≤ prescaler
 | 
					 | 
				
			||||||
	 */
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	prescaler = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk),
 | 
					 | 
				
			||||||
					(u64)NSEC_PER_SEC * ((u64)priv->max_arr + 1));
 | 
					 | 
				
			||||||
	if (prescaler > MAX_TIM_PSC)
 | 
					 | 
				
			||||||
		return -EINVAL;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	prd = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk),
 | 
					 | 
				
			||||||
				  (u64)NSEC_PER_SEC * (prescaler + 1));
 | 
					 | 
				
			||||||
	if (!prd)
 | 
					 | 
				
			||||||
		return -EINVAL;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/*
 | 
					 | 
				
			||||||
	 * All channels share the same prescaler and counter so when two
 | 
					 | 
				
			||||||
	 * channels are active at the same time we can't change them
 | 
					 | 
				
			||||||
	 */
 | 
					 | 
				
			||||||
	if (active_channels(priv) & ~(1 << ch * 4)) {
 | 
					 | 
				
			||||||
		u32 psc, arr;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
		regmap_read(priv->regmap, TIM_PSC, &psc);
 | 
					 | 
				
			||||||
		regmap_read(priv->regmap, TIM_ARR, &arr);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
		if ((psc != prescaler) || (arr != prd - 1))
 | 
					 | 
				
			||||||
			return -EBUSY;
 | 
					 | 
				
			||||||
	}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	regmap_write(priv->regmap, TIM_PSC, prescaler);
 | 
					 | 
				
			||||||
	regmap_write(priv->regmap, TIM_ARR, prd - 1);
 | 
					 | 
				
			||||||
	regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* Calculate the duty cycles */
 | 
					 | 
				
			||||||
	dty = mul_u64_u64_div_u64(duty_ns, clk_get_rate(priv->clk),
 | 
					 | 
				
			||||||
				  (u64)NSEC_PER_SEC * (prescaler + 1));
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	regmap_write(priv->regmap, TIM_CCRx(ch + 1), dty);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* Configure output mode */
 | 
					 | 
				
			||||||
	shift = (ch & 0x1) * CCMR_CHANNEL_SHIFT;
 | 
					 | 
				
			||||||
	ccmr = (TIM_CCMR_PE | TIM_CCMR_M1) << shift;
 | 
					 | 
				
			||||||
	mask = CCMR_CHANNEL_MASK << shift;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	if (ch < 2)
 | 
					 | 
				
			||||||
		regmap_update_bits(priv->regmap, TIM_CCMR1, mask, ccmr);
 | 
					 | 
				
			||||||
	else
 | 
					 | 
				
			||||||
		regmap_update_bits(priv->regmap, TIM_CCMR2, mask, ccmr);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	regmap_set_bits(priv->regmap, TIM_BDTR, TIM_BDTR_MOE);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	return 0;
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static int stm32_pwm_set_polarity(struct stm32_pwm *priv, unsigned int ch,
 | 
					 | 
				
			||||||
				  enum pwm_polarity polarity)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	u32 mask;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	mask = TIM_CCER_CCxP(ch + 1);
 | 
					 | 
				
			||||||
	if (priv->have_complementary_output)
 | 
					 | 
				
			||||||
		mask |= TIM_CCER_CCxNP(ch + 1);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	regmap_update_bits(priv->regmap, TIM_CCER, mask,
 | 
					 | 
				
			||||||
			   polarity == PWM_POLARITY_NORMAL ? 0 : mask);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	return 0;
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static int stm32_pwm_enable(struct stm32_pwm *priv, unsigned int ch)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	u32 mask;
 | 
					 | 
				
			||||||
	int ret;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	ret = clk_enable(priv->clk);
 | 
					 | 
				
			||||||
	if (ret)
 | 
					 | 
				
			||||||
		return ret;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* Enable channel */
 | 
					 | 
				
			||||||
	mask = TIM_CCER_CCxE(ch + 1);
 | 
					 | 
				
			||||||
	if (priv->have_complementary_output)
 | 
					 | 
				
			||||||
		mask |= TIM_CCER_CCxNE(ch + 1);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	regmap_set_bits(priv->regmap, TIM_CCER, mask);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* Make sure that registers are updated */
 | 
					 | 
				
			||||||
	regmap_set_bits(priv->regmap, TIM_EGR, TIM_EGR_UG);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* Enable controller */
 | 
					 | 
				
			||||||
	regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	return 0;
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static void stm32_pwm_disable(struct stm32_pwm *priv, unsigned int ch)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	u32 mask;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* Disable channel */
 | 
					 | 
				
			||||||
	mask = TIM_CCER_CCxE(ch + 1);
 | 
					 | 
				
			||||||
	if (priv->have_complementary_output)
 | 
					 | 
				
			||||||
		mask |= TIM_CCER_CCxNE(ch + 1);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	regmap_clear_bits(priv->regmap, TIM_CCER, mask);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* When all channels are disabled, we can disable the controller */
 | 
					 | 
				
			||||||
	if (!active_channels(priv))
 | 
					 | 
				
			||||||
		regmap_clear_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	clk_disable(priv->clk);
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static int stm32_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 | 
					 | 
				
			||||||
			   const struct pwm_state *state)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	bool enabled;
 | 
					 | 
				
			||||||
	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
 | 
					 | 
				
			||||||
	int ret;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	enabled = pwm->state.enabled;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	if (!state->enabled) {
 | 
					 | 
				
			||||||
		if (enabled)
 | 
					 | 
				
			||||||
			stm32_pwm_disable(priv, pwm->hwpwm);
 | 
					 | 
				
			||||||
		return 0;
 | 
					 | 
				
			||||||
	}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	if (state->polarity != pwm->state.polarity)
 | 
					 | 
				
			||||||
		stm32_pwm_set_polarity(priv, pwm->hwpwm, state->polarity);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	ret = stm32_pwm_config(priv, pwm->hwpwm,
 | 
					 | 
				
			||||||
			       state->duty_cycle, state->period);
 | 
					 | 
				
			||||||
	if (ret)
 | 
					 | 
				
			||||||
		return ret;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	if (!enabled && state->enabled)
 | 
					 | 
				
			||||||
		ret = stm32_pwm_enable(priv, pwm->hwpwm);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	return ret;
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static int stm32_pwm_apply_locked(struct pwm_chip *chip, struct pwm_device *pwm,
 | 
					 | 
				
			||||||
				  const struct pwm_state *state)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
 | 
					 | 
				
			||||||
	int ret;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	/* protect common prescaler for all active channels */
 | 
					 | 
				
			||||||
	mutex_lock(&priv->lock);
 | 
					 | 
				
			||||||
	ret = stm32_pwm_apply(chip, pwm, state);
 | 
					 | 
				
			||||||
	mutex_unlock(&priv->lock);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	return ret;
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static int stm32_pwm_get_state(struct pwm_chip *chip,
 | 
					 | 
				
			||||||
			       struct pwm_device *pwm, struct pwm_state *state)
 | 
					 | 
				
			||||||
{
 | 
					 | 
				
			||||||
	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
 | 
					 | 
				
			||||||
	int ch = pwm->hwpwm;
 | 
					 | 
				
			||||||
	unsigned long rate;
 | 
					 | 
				
			||||||
	u32 ccer, psc, arr, ccr;
 | 
					 | 
				
			||||||
	u64 dty, prd;
 | 
					 | 
				
			||||||
	int ret;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	mutex_lock(&priv->lock);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	ret = regmap_read(priv->regmap, TIM_CCER, &ccer);
 | 
					 | 
				
			||||||
	if (ret)
 | 
					 | 
				
			||||||
		goto out;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	state->enabled = ccer & TIM_CCER_CCxE(ch + 1);
 | 
					 | 
				
			||||||
	state->polarity = (ccer & TIM_CCER_CCxP(ch + 1)) ?
 | 
					 | 
				
			||||||
			  PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
 | 
					 | 
				
			||||||
	ret = regmap_read(priv->regmap, TIM_PSC, &psc);
 | 
					 | 
				
			||||||
	if (ret)
 | 
					 | 
				
			||||||
		goto out;
 | 
					 | 
				
			||||||
	ret = regmap_read(priv->regmap, TIM_ARR, &arr);
 | 
					 | 
				
			||||||
	if (ret)
 | 
					 | 
				
			||||||
		goto out;
 | 
					 | 
				
			||||||
	ret = regmap_read(priv->regmap, TIM_CCRx(ch + 1), &ccr);
 | 
					 | 
				
			||||||
	if (ret)
 | 
					 | 
				
			||||||
		goto out;
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	rate = clk_get_rate(priv->clk);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
	prd = (u64)NSEC_PER_SEC * (psc + 1) * (arr + 1);
 | 
					 | 
				
			||||||
	state->period = DIV_ROUND_UP_ULL(prd, rate);
 | 
					 | 
				
			||||||
	dty = (u64)NSEC_PER_SEC * (psc + 1) * ccr;
 | 
					 | 
				
			||||||
	state->duty_cycle = DIV_ROUND_UP_ULL(dty, rate);
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
out:
 | 
					 | 
				
			||||||
	mutex_unlock(&priv->lock);
 | 
					 | 
				
			||||||
	return ret;
 | 
					 | 
				
			||||||
}
 | 
					 | 
				
			||||||
 | 
					 | 
				
			||||||
static const struct pwm_ops stm32pwm_ops = {
 | 
					static const struct pwm_ops stm32pwm_ops = {
 | 
				
			||||||
	.apply = stm32_pwm_apply_locked,
 | 
						.sizeof_wfhw = sizeof(struct stm32_pwm_waveform),
 | 
				
			||||||
	.get_state = stm32_pwm_get_state,
 | 
						.round_waveform_tohw = stm32_pwm_round_waveform_tohw,
 | 
				
			||||||
 | 
						.round_waveform_fromhw = stm32_pwm_round_waveform_fromhw,
 | 
				
			||||||
 | 
						.read_waveform = stm32_pwm_read_waveform,
 | 
				
			||||||
 | 
						.write_waveform = stm32_pwm_write_waveform,
 | 
				
			||||||
 | 
					
 | 
				
			||||||
	.capture = IS_ENABLED(CONFIG_DMA_ENGINE) ? stm32_pwm_capture : NULL,
 | 
						.capture = IS_ENABLED(CONFIG_DMA_ENGINE) ? stm32_pwm_capture : NULL,
 | 
				
			||||||
};
 | 
					};
 | 
				
			||||||
 | 
					
 | 
				
			||||||
| 
						 | 
					
 | 
				
			||||||
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		Reference in a new issue