On Thu, 2 Sep 2021 23:51:19 +0200 Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote: > TI AM335X TRM [1] states that most of the configuration should be set in > the control register in the first place, before actually enabling the > hardware with the subsystem enable bit. > > So far only half of the configuration was made in the first step (before > enabling the "subsystem"), which does not make really sense. Also, the > probe and the resume patch were acting differently. Let's harmonize all > this by following these steps: > 1/ Configure the CLKDIV register > 2/ Configure the CTRL register > 3/ Configure the idle configuration > 4/ Really enable the device by rewriting the CTRL register with the > subsystem enable bit set. > > [1] https://www.ti.com/lit/pdf/spruh73 > > Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> This tidies up the other patches which is good. Now I haven't checked the new order against the datasheet but it now does things as you describe so I'm assuming that's fine. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > --- > drivers/mfd/ti_am335x_tscadc.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c > index 5f189da99468..61f878c7593b 100644 > --- a/drivers/mfd/ti_am335x_tscadc.c > +++ b/drivers/mfd/ti_am335x_tscadc.c > @@ -221,8 +221,6 @@ static int ti_tscadc_probe(struct platform_device *pdev) > > /* Set the control register bits */ > ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID; > - regmap_write(tscadc->regmap, REG_CTRL, ctrl); > - > if (tsc_wires > 0) { > tscadc->tsc_wires = tsc_wires; > if (tsc_wires == 5) > @@ -230,6 +228,7 @@ static int ti_tscadc_probe(struct platform_device *pdev) > else > ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB; > } > + regmap_write(tscadc->regmap, REG_CTRL, ctrl); > > tscadc_idle_config(tscadc); > > @@ -315,9 +314,9 @@ static int __maybe_unused tscadc_resume(struct device *dev) > pm_runtime_get_sync(dev); > > /* context restore */ > - ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID; > - regmap_write(tscadc->regmap, REG_CTRL, ctrl); > + regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div); > > + ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID; > if (tscadc->tsc_wires > 0) { > if (tscadc->tsc_wires == 5) > ctrl |= CNTRLREG_5WIRE | CNTRLREG_TSCENB; > @@ -325,13 +324,13 @@ static int __maybe_unused tscadc_resume(struct device *dev) > ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB; > } > > + regmap_write(tscadc->regmap, REG_CTRL, ctrl); > + > tscadc_idle_config(tscadc); > > ctrl |= CNTRLREG_TSCSSENB; > regmap_write(tscadc->regmap, REG_CTRL, ctrl); > > - regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div); > - > return 0; > } >
