diff options
| author |   Jitao Shi <jitao.shi@mediatek.com> | 2021-08-08 21:24:33 +0800 |
|---|---|---|
| committer |   Thierry Reding <thierry.reding@gmail.com> | 2021-09-02 22:27:46 +0200 |
| commit | 3f2b16734914fa7c53ef7f8a10a63828890dbd37 (patch) | |
| tree | 9a791958e0ae6d1b1fb9737eef14286fed39788d | |
| parent | pwm: mtk-disp: Fix overflow in period and duty calculation (diff) | |
| download | linux-dev-3f2b16734914fa7c53ef7f8a10a63828890dbd37.tar.xz linux-dev-3f2b16734914fa7c53ef7f8a10a63828890dbd37.zip | |
pwm: mtk-disp: Implement atomic API .get_state()
Switch the driver to support the .get_state() method.
Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
[thierry.reding@gmail.com: add missing linux/bitfield.h include]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
| -rw-r--r-- | drivers/pwm/pwm-mtk-disp.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c index 73f8103a782c..c605013e4114 100644 --- a/drivers/pwm/pwm-mtk-disp.c +++ b/drivers/pwm/pwm-mtk-disp.c @@ -5,6 +5,7 @@ * Author: YH Huang <yh.huang@mediatek.com> */ +#include <linux/bitfield.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> @@ -171,8 +172,50 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } +static void mtk_disp_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip); + u64 rate, period, high_width; + u32 clk_div, con0, con1; + int err; + + err = clk_prepare_enable(mdp->clk_main); + if (err < 0) { + dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n", ERR_PTR(err)); + return; + } + + err = clk_prepare_enable(mdp->clk_mm); + if (err < 0) { + dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n", ERR_PTR(err)); + clk_disable_unprepare(mdp->clk_main); + return; + } + + rate = clk_get_rate(mdp->clk_main); + con0 = readl(mdp->base + mdp->data->con0); + con1 = readl(mdp->base + mdp->data->con1); + state->enabled = !!(con0 & BIT(0)); + clk_div = FIELD_GET(PWM_CLKDIV_MASK, con0); + period = FIELD_GET(PWM_PERIOD_MASK, con1); + /* + * period has 12 bits, clk_div 11 and NSEC_PER_SEC has 30, + * so period * (clk_div + 1) * NSEC_PER_SEC doesn't overflow. + */ + state->period = DIV64_U64_ROUND_UP(period * (clk_div + 1) * NSEC_PER_SEC, rate); + high_width = FIELD_GET(PWM_HIGH_WIDTH_MASK, con1); + state->duty_cycle = DIV64_U64_ROUND_UP(high_width * (clk_div + 1) * NSEC_PER_SEC, + rate); + state->polarity = PWM_POLARITY_NORMAL; + clk_disable_unprepare(mdp->clk_mm); + clk_disable_unprepare(mdp->clk_main); +} + static const struct pwm_ops mtk_disp_pwm_ops = { .apply = mtk_disp_pwm_apply, + .get_state = mtk_disp_pwm_get_state, .owner = THIS_MODULE, }; |