On Mon, 10 Aug 2026 12:45:16 +0200 "H. Nikolaus Schaller" <[email protected]> wrote:
> Hi Daniel, > > > Am 10.08.2026 um 12:35 schrieb Daniel Thompson <[email protected]>: > > > > On Sat, Jul 11, 2026 at 08:02:02AM +0200, H. Nikolaus Schaller wrote: > >> Retire the platform specific pandora backlight driver since > >> it can now be replaced by twl_pm and device tree. > >> > >> Signed-off-by: H. Nikolaus Schaller <[email protected]> > > > > Yay! > > > > Reviewed-by: Daniel Thompson (RISCstar) <[email protected]> > > Well, there were some good comments by Sahiko to the prerequisites of this > patch, > because it has one speciality the PWM BL driver does not handle (avoid > interpretation of PWM signals as W1 protocol). > > I haven't found time to work on this, so we can't remove this yet. > > In the end it may either remain a pandora_bl driver (converted to DT) > or become a patch for something else. > But then it is a TPS61161 on top of PWM, not a pandora driver. And then there might be just a quirk for that chip in the pwm_bl using triggered by a compatible. I guess the quirk is this: if (priv->old_state == PANDORABL_WAS_OFF) { - /* - * set PWM duty cycle to max. TPS61161 seems to use this - * to calibrate it's PWM sensitivity when it starts. - */ - twl_i2c_write_u8(TWL_MODULE_PWM, MAX_VALUE, TWL_PWM0_OFF); - - /* first enable clock, then PWM0 out */ - twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1); - r &= ~PWM0_ENABLE; - r |= PWM0_CLK_ENABLE; - twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1); - r |= PWM0_ENABLE; - twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1); - - /* - * TI made it very easy to enable digital control, so easy that - * it often triggers unintentionally and disabes PWM control, - * so wait until 1 wire mode detection window ends. - */ - usleep_range(2000, 10000); - } Regards, Andreas
