Re: [PATCH v5 2/3] pwm: mtk_disp: implement atomic API .apply()
From: Uwe Kleine-König <hidden>
Date: 2021-06-25 17:52:31
Also in:
linux-arm-kernel, linux-pwm, lkml
On Wed, Jun 16, 2021 at 04:52:23PM +0800, Jitao Shi wrote:
quoted hunk ↗ jump to hunk
Switch the driver to support the .apply() method. Signed-off-by: Jitao Shi <redacted> --- drivers/pwm/pwm-mtk-disp.c | 69 ++++++++++---------------------------- 1 file changed, 17 insertions(+), 52 deletions(-)diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c index 204d76beeb26..a4766e931b68 100644 --- a/drivers/pwm/pwm-mtk-disp.c +++ b/drivers/pwm/pwm-mtk-disp.c@@ -67,14 +67,25 @@ static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset, writel(value, address); } -static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, - int duty_ns, int period_ns) +static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) { struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip); u32 clk_div, period, high_width, value; u64 div, rate; int err;
Here something like: if (state->polarity != PWM_POLARITY_NORMAL) return -EINVAL; is missing.
quoted hunk ↗ jump to hunk
+ if (!state->enabled) { + mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask, + 0x0); + if (mdp->enabled) { + clk_disable_unprepare(mdp->clk_mm); + clk_disable_unprepare(mdp->clk_main); + } + mdp->enabled = false; + return 0; + } + if (!mdp->enabled) { err = clk_prepare_enable(mdp->clk_main); if (err < 0) {@@ -102,7 +113,7 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, * high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1)) */ rate = clk_get_rate(mdp->clk_main); - clk_div = div_u64(rate * period_ns, NSEC_PER_SEC) >> + clk_div = div_u64(rate * state->period, NSEC_PER_SEC) >>
This multiplication might overflow. But maybe it's sensible to address this in a separate commit to keep things simple.
quoted hunk ↗ jump to hunk
PWM_PERIOD_BIT_WIDTH; if (clk_div > PWM_CLKDIV_MAX) { if (!mdp->enabled) {@@ -112,11 +123,11 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, return -EINVAL; } div = NSEC_PER_SEC * (clk_div + 1); - period = div64_u64(rate * period_ns, div); + period = div64_u64(rate * state->period, div);
ditto. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |