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authorJitao Shi <jitao.shi@mediatek.com>2021-08-08 21:24:33 +0800
committerThierry Reding <thierry.reding@gmail.com>2021-09-02 22:27:46 +0200
commit3f2b16734914fa7c53ef7f8a10a63828890dbd37 (patch)
tree9a791958e0ae6d1b1fb9737eef14286fed39788d /drivers/pwm
parent331e049dec64c2d269648a3ea4ea6aae8a54b4ac (diff)
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>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-mtk-disp.c43
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,
};