Exemplo n.º 1
0
int pwm_config(int pwm_id, int duty_ns, int period_ns)
{
	const struct s5p_timer *pwm =
			(struct s5p_timer *)samsung_get_base_timer();
	unsigned int offset;
	unsigned long tin_rate;
	unsigned long tin_ns;
	unsigned long frequency;
	unsigned long tcon;
	unsigned long tcnt;
	unsigned long tcmp;

	/*
	 * We currently avoid using 64bit arithmetic by using the
	 * fact that anything faster than 1GHz is easily representable
	 * by 32bits.
	 */
	if (period_ns > NS_IN_SEC || duty_ns > NS_IN_SEC || period_ns == 0)
		return -ERANGE;

	if (duty_ns > period_ns)
		return -EINVAL;

	frequency = NS_IN_SEC / period_ns;

	/* Check to see if we are changing the clock rate of the PWM */
	tin_rate = pwm_calc_tin(pwm_id, frequency);

	tin_ns = NS_IN_SEC / tin_rate;
	tcnt = period_ns / tin_ns;

	/* Note, counters count down */
	tcmp = duty_ns / tin_ns;
	tcmp = tcnt - tcmp;

	/* Update the PWM register block. */
	offset = pwm_id * 3;
	if (pwm_id < 4) {
		writel(tcnt, &pwm->tcntb0 + offset);
		writel(tcmp, &pwm->tcmpb0 + offset);
	}

	tcon = readl(&pwm->tcon);
	tcon |= TCON_UPDATE(pwm_id);
	if (pwm_id < 4)
		tcon |= TCON_AUTO_RELOAD(pwm_id);
	else
		tcon |= TCON4_AUTO_RELOAD;
	writel(tcon, &pwm->tcon);

	tcon &= ~TCON_UPDATE(pwm_id);
	writel(tcon, &pwm->tcon);

	return 0;
}
Exemplo n.º 2
0
static int s3c_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
		int duty_ns, int period_ns)
{
	struct s3c_chip *s3c = to_s3c_chip(chip);
	unsigned long tin_rate;
	unsigned long tin_ns;
	unsigned long period;
	unsigned long flags;
	unsigned long tcon;
	unsigned long tcnt;
	long tcmp;

	/* We currently avoid using 64bit arithmetic by using the
	 * fact that anything faster than 1Hz is easily representable
	 * by 32bits. */

	if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ)
		return -ERANGE;

	if (duty_ns > period_ns)
		return -EINVAL;

	if (period_ns == s3c->period_ns &&
	    duty_ns == s3c->duty_ns)
		return 0;

	/* The TCMP and TCNT can be read without a lock, they're not
	 * shared between the timers. */

	tcmp = __raw_readl(S3C2410_TCMPB(s3c->pwm_id));
	tcnt = __raw_readl(S3C2410_TCNTB(s3c->pwm_id));

	period = NS_IN_HZ / period_ns;

	pwm_dbg(s3c, "duty_ns=%d, period_ns=%d (%lu)\n",
		duty_ns, period_ns, period);

	/* Check to see if we are changing the clock rate of the PWM */

	if (s3c->period_ns != period_ns) {
		if (pwm_is_tdiv(s3c)) {
			tin_rate = pwm_calc_tin(s3c, period);
			clk_set_rate(s3c->clk_div, tin_rate);
		} else
			tin_rate = clk_get_rate(s3c->clk);

		s3c->period_ns = period_ns;

		pwm_dbg(s3c, "tin_rate=%lu\n", tin_rate);

		tin_ns = NS_IN_HZ / tin_rate;
		tcnt = period_ns / tin_ns;
	} else
		tin_ns = NS_IN_HZ / clk_get_rate(s3c->clk);

	/* Note, counters count down */

	tcmp = duty_ns / tin_ns;
	tcmp = tcnt - tcmp;
	/* the pwm hw only checks the compare register after a decrement,
	   so the pin never toggles if tcmp = tcnt */
	if (tcmp == tcnt)
		tcmp--;

	pwm_dbg(s3c, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);

	if (tcmp < 0)
		tcmp = 0;

	/* Update the PWM register block. */

	local_irq_save(flags);

	__raw_writel(tcmp, S3C2410_TCMPB(s3c->pwm_id));
	__raw_writel(tcnt, S3C2410_TCNTB(s3c->pwm_id));

	tcon = __raw_readl(S3C2410_TCON);
	tcon |= pwm_tcon_manulupdate(s3c);
	tcon |= pwm_tcon_autoreload(s3c);
	__raw_writel(tcon, S3C2410_TCON);

	tcon &= ~pwm_tcon_manulupdate(s3c);
	__raw_writel(tcon, S3C2410_TCON);

	local_irq_restore(flags);

	return 0;
}
Exemplo n.º 3
0
static int s3c_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
		int duty_ns, int period_ns)
{
	struct s3c_chip *s3c = to_s3c_chip(chip);
	struct s3c_pwm_device *s3c_pwm = pwm_get_chip_data(pwm);
	void __iomem *reg_base = s3c->reg_base;
	unsigned long tin_rate;
	unsigned long tin_ns;
	unsigned long period;
	unsigned long flags;
	unsigned long tcon;
	unsigned long tcnt;
	long tcmp;
	enum duty_cycle duty_cycle;
	unsigned int id = pwm->pwm;

	/* We currently avoid using 64bit arithmetic by using the
	 * fact that anything faster than 1Hz is easily representable
	 * by 32bits. */

	if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ)
		return -ERANGE;

	if (duty_ns > period_ns)
		return -EINVAL;

	if (period_ns == s3c_pwm->period_ns &&
	    duty_ns == s3c_pwm->duty_ns)
		return 0;

	period = NS_IN_HZ / period_ns;

	/* Check to see if we are changing the clock rate of the PWM */

	if (s3c_pwm->period_ns != period_ns && pwm_is_tdiv(s3c_pwm)) {
		tin_rate = pwm_calc_tin(pwm, period);
		clk_set_rate(s3c_pwm->clk_div, tin_rate);
		tin_rate = clk_get_rate(s3c_pwm->clk_div);
		s3c_pwm->period_ns = period_ns;
		pwm_dbg(s3c, "tin_rate=%lu\n", tin_rate);
	} else {
		tin_rate = clk_get_rate(s3c_pwm->clk_tin);
	}

	if(!tin_rate)
		return -EFAULT;

	/* Note, counters count down */
	tin_ns = NS_IN_HZ / tin_rate;

	tcnt = DIV_ROUND_CLOSEST(period_ns, tin_ns);
	tcmp = DIV_ROUND_CLOSEST(duty_ns, tin_ns);

	if (tcnt <= 1) {
		/* Too small to generate a pulse */
		return -ERANGE;
	}

	pwm_dbg(s3c, "duty_ns=%d, period_ns=%d (%lu)\n",
		duty_ns, period_ns, period);

	if (tcmp == 0)
		duty_cycle = DUTY_CYCLE_ZERO;
	else if (tcmp == tcnt)
		duty_cycle = DUTY_CYCLE_FULL;
	else
		duty_cycle = DUTY_CYCLE_PULSE;

	tcmp = tcnt - tcmp;
	/* the pwm hw only checks the compare register after a decrement,
	   so the pin never toggles if tcmp = tcnt */
	if (tcmp == tcnt)
		tcmp--;

	/*
	 * PWM counts 1 hidden tick at the end of each period on S3C64XX and
	 * EXYNOS series, so tcmp and tcnt should be subtracted 1.
	 */
	if (!pwm_is_s3c24xx(s3c)) {
		tcnt--;
		/*
		 * tcmp can be -1. It appears 100% duty cycle and PWM never
		 * toggles when TCMPB is set to 0xFFFFFFFF (-1).
		 */
		tcmp--;
	}

	pwm_dbg(s3c, "tin_ns=%lu, tcmp=%ld/%lu\n", tin_ns, tcmp, tcnt);

	/* Update the PWM register block. */

	spin_lock_irqsave(&pwm_spinlock, flags);

	__raw_writel(tcmp, reg_base + REG_TCMPB(id));
	__raw_writel(tcnt, reg_base + REG_TCNTB(id));

	if (pwm_is_s3c24xx(s3c)) {
		tcon = __raw_readl(reg_base + REG_TCON);
		tcon |= pwm_tcon_manulupdate(s3c_pwm);
		tcon |= pwm_tcon_autoreload(s3c_pwm);
		__raw_writel(tcon, reg_base + REG_TCON);

		tcon &= ~pwm_tcon_manulupdate(s3c_pwm);
		__raw_writel(tcon, reg_base + REG_TCON);
	} else {
		tcon = __raw_readl(reg_base + REG_TCON);
		if (s3c_pwm->running == 1 &&
		    tcon & pwm_tcon_start(s3c_pwm) &&
		    s3c_pwm->duty_cycle != duty_cycle) {
			if (duty_cycle == DUTY_CYCLE_ZERO) {
				tcon |= pwm_tcon_manulupdate(s3c_pwm);
				__raw_writel(tcon, reg_base + REG_TCON);

				tcon &= ~pwm_tcon_manulupdate(s3c_pwm);
				tcon &= ~pwm_tcon_autoreload(s3c_pwm);
			} else {
				tcon |= pwm_tcon_autoreload(s3c_pwm);
			}
			__raw_writel(tcon, reg_base + REG_TCON);
		}
	}
	s3c_pwm->duty_ns = duty_ns;
	s3c_pwm->period_ns = period_ns;
	s3c_pwm->duty_cycle = duty_cycle;

	spin_unlock_irqrestore(&pwm_spinlock, flags);

	return 0;
}
Exemplo n.º 4
0
int pwm_config(int pwm_id, int duty_ns, int period_ns)
{
	const struct s5p_timer *pwm =
			(struct s5p_timer *)samsung_get_base_timer();
	unsigned int offset;
	unsigned long tin_rate;
	unsigned long tin_ns;
	unsigned long period;
	unsigned long tcon;
	unsigned long tcnt;
	unsigned long timer_rate_hz;
	unsigned long tcmp;

	/*
	 * We currently avoid using 64bit arithmetic by using the
	 * fact that anything faster than 1GHz is easily representable
	 * by 32bits.
	 */
	if (period_ns > NS_IN_HZ || duty_ns > NS_IN_HZ)
		return -ERANGE;

	if (duty_ns > period_ns)
		return -EINVAL;

	period = NS_IN_HZ / period_ns;

	/* Check to see if we are changing the clock rate of the PWM */
	tin_rate = pwm_calc_tin(pwm_id, period);
	timer_rate_hz = tin_rate;

	tin_ns = NS_IN_HZ / tin_rate;
	tcnt = period_ns / tin_ns;

	/* Note, counters count down */
	tcmp = duty_ns / tin_ns;
	tcmp = tcnt - tcmp;

	/*
	 * the pwm hw only checks the compare register after a decrement,
	 * so the pin never toggles if tcmp = tcnt
	 */
	if (tcmp == tcnt)
		tcmp--;

	if (tcmp < 0)
		tcmp = 0;

	/* Update the PWM register block. */
	offset = pwm_id * 3;
	if (pwm_id < 4) {
		writel(tcnt, &pwm->tcntb0 + offset);
		writel(tcmp, &pwm->tcmpb0 + offset);
	}

	tcon = readl(&pwm->tcon);
	tcon |= TCON_UPDATE(pwm_id);
	if (pwm_id < 4)
		tcon |= TCON_AUTO_RELOAD(pwm_id);
	else
		tcon |= TCON4_AUTO_RELOAD;
	writel(tcon, &pwm->tcon);

	tcon &= ~TCON_UPDATE(pwm_id);
	writel(tcon, &pwm->tcon);

	return 0;
}