diff options
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-fsl-ftm.c | 6 | ||||
| -rw-r--r-- | drivers/pwm/pwm-mediatek.c | 8 | ||||
| -rw-r--r-- | drivers/pwm/pwm-rcar.c | 24 |
3 files changed, 25 insertions, 13 deletions
diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c index 0247757f9a72..6751f3d00560 100644 --- a/drivers/pwm/pwm-fsl-ftm.c +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -123,6 +123,9 @@ static unsigned int fsl_pwm_ticks_to_ns(struct fsl_pwm_chip *fpc, unsigned long long exval; rate = clk_get_rate(fpc->clk[fpc->period.clk_select]); + if (rate >> fpc->period.clk_ps == 0) + return 0; + exval = ticks; exval *= 1000000000UL; do_div(exval, rate >> fpc->period.clk_ps); @@ -195,6 +198,9 @@ static unsigned int fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc, unsigned int period = fpc->period.mod_period + 1; unsigned int period_ns = fsl_pwm_ticks_to_ns(fpc, period); + if (!period_ns) + return 0; + duty = (unsigned long long)duty_ns * period; do_div(duty, period_ns); diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c index f8f9a7489129..bb764428bfe7 100644 --- a/drivers/pwm/pwm-mediatek.c +++ b/drivers/pwm/pwm-mediatek.c @@ -120,21 +120,25 @@ static int pwm_mediatek_config(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_mediatek_chip *pc = to_pwm_mediatek_chip(chip); u32 clkdiv = 0, cnt_period, cnt_duty, reg_width = PWMDWIDTH, reg_thres = PWMTHRES; + unsigned long clk_rate; u64 resolution; int ret; ret = pwm_mediatek_clk_enable(chip, pwm); - if (ret < 0) return ret; + clk_rate = clk_get_rate(pc->clk_pwms[pwm->hwpwm]); + if (!clk_rate) + return -EINVAL; + /* Make sure we use the bus clock and not the 26MHz clock */ if (pc->soc->has_ck_26m_sel) writel(0, pc->regs + PWM_CK_26M_SEL); /* Using resolution in picosecond gets accuracy higher */ resolution = (u64)NSEC_PER_SEC * 1000; - do_div(resolution, clk_get_rate(pc->clk_pwms[pwm->hwpwm])); + do_div(resolution, clk_rate); cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000, resolution); while (cnt_period > 8191) { diff --git a/drivers/pwm/pwm-rcar.c b/drivers/pwm/pwm-rcar.c index b437192380e2..b2e75d870532 100644 --- a/drivers/pwm/pwm-rcar.c +++ b/drivers/pwm/pwm-rcar.c @@ -8,6 +8,7 @@ * - The hardware cannot generate a 0% duty cycle. */ +#include <linux/bitfield.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> @@ -103,23 +104,24 @@ static void rcar_pwm_set_clock_control(struct rcar_pwm_chip *rp, rcar_pwm_write(rp, value, RCAR_PWMCR); } -static int rcar_pwm_set_counter(struct rcar_pwm_chip *rp, int div, int duty_ns, - int period_ns) +static int rcar_pwm_set_counter(struct rcar_pwm_chip *rp, int div, u64 duty_ns, + u64 period_ns) { - unsigned long long one_cycle, tmp; /* 0.01 nanoseconds */ + unsigned long long tmp; unsigned long clk_rate = clk_get_rate(rp->clk); u32 cyc, ph; - one_cycle = (unsigned long long)NSEC_PER_SEC * 100ULL * (1 << div); - do_div(one_cycle, clk_rate); + /* div <= 24 == RCAR_PWM_MAX_DIVISION, so the shift doesn't overflow. */ + tmp = mul_u64_u64_div_u64(period_ns, clk_rate, (u64)NSEC_PER_SEC << div); + if (tmp > FIELD_MAX(RCAR_PWMCNT_CYC0_MASK)) + tmp = FIELD_MAX(RCAR_PWMCNT_CYC0_MASK); - tmp = period_ns * 100ULL; - do_div(tmp, one_cycle); - cyc = (tmp << RCAR_PWMCNT_CYC0_SHIFT) & RCAR_PWMCNT_CYC0_MASK; + cyc = FIELD_PREP(RCAR_PWMCNT_CYC0_MASK, tmp); - tmp = duty_ns * 100ULL; - do_div(tmp, one_cycle); - ph = tmp & RCAR_PWMCNT_PH0_MASK; + tmp = mul_u64_u64_div_u64(duty_ns, clk_rate, (u64)NSEC_PER_SEC << div); + if (tmp > FIELD_MAX(RCAR_PWMCNT_PH0_MASK)) + tmp = FIELD_MAX(RCAR_PWMCNT_PH0_MASK); + ph = FIELD_PREP(RCAR_PWMCNT_PH0_MASK, tmp); /* Avoid prohibited setting */ if (cyc == 0 || ph == 0) |