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authorGravatar AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> 2023-04-03 15:30:53 +0200
committerGravatar Thierry Reding <thierry.reding@gmail.com> 2023-04-06 16:23:22 +0200
commit36dd7f530ae7d9ce9e853ffb8aa337de65c6600b (patch)
tree5d53f90cf585de8ea5c14f47c554d6c7a4d84db1 /drivers/pwm/pwm-mtk-disp.c
parentpwm: stm32-lp: Drop of_match_ptr for ID table (diff)
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pwm: mtk-disp: Disable shadow registers before setting backlight values
If shadow registers usage is not desired, disable that before performing any write to CON0/1 registers in the .apply() callback, otherwise we may lose clkdiv or period/width updates. Fixes: cd4b45ac449a ("pwm: Add MediaTek MT2701 display PWM driver support") Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com> Tested-by: Alexandre Mergnat <amergnat@baylibre.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm/pwm-mtk-disp.c')
-rw-r--r--drivers/pwm/pwm-mtk-disp.c24
1 files changed, 13 insertions, 11 deletions
diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 4cfe88d54652..ea361976eb34 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -138,6 +138,19 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
high_width = mul_u64_u64_div_u64(state->duty_cycle, rate, div);
value = period | (high_width << PWM_HIGH_WIDTH_SHIFT);
+ if (mdp->data->bls_debug && !mdp->data->has_commit) {
+ /*
+ * For MT2701, disable double buffer before writing register
+ * and select manual mode and use PWM_PERIOD/PWM_HIGH_WIDTH.
+ */
+ mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
+ mdp->data->bls_debug_mask,
+ mdp->data->bls_debug_mask);
+ mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
+ mdp->data->con0_sel,
+ mdp->data->con0_sel);
+ }
+
mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
PWM_CLKDIV_MASK,
clk_div << PWM_CLKDIV_SHIFT);
@@ -152,17 +165,6 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
mtk_disp_pwm_update_bits(mdp, mdp->data->commit,
mdp->data->commit_mask,
0x0);
- } else {
- /*
- * For MT2701, disable double buffer before writing register
- * and select manual mode and use PWM_PERIOD/PWM_HIGH_WIDTH.
- */
- mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
- mdp->data->bls_debug_mask,
- mdp->data->bls_debug_mask);
- mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
- mdp->data->con0_sel,
- mdp->data->con0_sel);
}
mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,