diff options
| author | AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> | 2023-04-03 15:30:53 +0200 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2023-04-06 16:23:22 +0200 |
| commit | 36dd7f530ae7d9ce9e853ffb8aa337de65c6600b (patch) | |
| tree | 5d53f90cf585de8ea5c14f47c554d6c7a4d84db1 /drivers/pwm | |
| parent | fa359c1938adbd04cf7e68786ea58366dddc3ad7 (diff) | |
| download | lwn-36dd7f530ae7d9ce9e853ffb8aa337de65c6600b.tar.gz lwn-36dd7f530ae7d9ce9e853ffb8aa337de65c6600b.zip | |
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')
| -rw-r--r-- | drivers/pwm/pwm-mtk-disp.c | 24 |
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, |