pwm: meson: Consider 128 a valid pre-divider
authorMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Mon, 1 Apr 2019 18:18:16 +0000 (20:18 +0200)
committerThierry Reding <thierry.reding@gmail.com>
Thu, 9 May 2019 14:50:04 +0000 (16:50 +0200)
The pre-divider allows configuring longer PWM periods compared to using
the input clock directly. The pre-divider is 7 bit wide, meaning it's
maximum value is 128 (the register value is off-by-one: 0x7f or 127).

Change the loop to also allow for the maximum possible value to be
considered valid.

Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
drivers/pwm/pwm-meson.c

index c1ed641b3e26622041c0fead2931a13bface7454..aaae48ab484ef0069c6b0bf957ef7fb7ab07df9d 100644 (file)
@@ -184,7 +184,7 @@ static int meson_pwm_calc(struct meson_pwm *meson,
        do_div(fin_ps, fin_freq);
 
        /* Calc pre_div with the period */
-       for (pre_div = 0; pre_div < MISC_CLK_DIV_MASK; pre_div++) {
+       for (pre_div = 0; pre_div <= MISC_CLK_DIV_MASK; pre_div++) {
                cnt = DIV_ROUND_CLOSEST_ULL((u64)period * 1000,
                                            fin_ps * (pre_div + 1));
                dev_dbg(meson->chip.dev, "fin_ps=%llu pre_div=%u cnt=%u\n",
@@ -193,7 +193,7 @@ static int meson_pwm_calc(struct meson_pwm *meson,
                        break;
        }
 
-       if (pre_div == MISC_CLK_DIV_MASK) {
+       if (pre_div > MISC_CLK_DIV_MASK) {
                dev_err(meson->chip.dev, "unable to get period pre_div\n");
                return -EINVAL;
        }