On Wed, 25 Aug 2021 17:24:58 +0200
Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:
> Instead of deriving in the probe and in the resume path the value of the
> ctrl register, let's do it only once in the probe, save the value of
> this register in the driver's structure and use it from the resume
> callback.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
A few minor things inline.
J
> ---
> drivers/mfd/ti_am335x_tscadc.c | 31 ++++++++--------------------
> include/linux/mfd/ti_am335x_tscadc.h | 2 +-
> 2 files changed, 10 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
> index 7071344ad18e..d661e8ae66c9 100644
> --- a/drivers/mfd/ti_am335x_tscadc.c
> +++ b/drivers/mfd/ti_am335x_tscadc.c
> @@ -122,7 +122,7 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> struct clk *clk;
> u32 val;
> int tsc_wires = 0, adc_channels = 0, readouts = 0, cell_idx = 0;
> - int total_channels, ctrl, err;
> + int total_channels, err;
>
> /* Allocate memory for device */
> tscadc = devm_kzalloc(&pdev->dev, sizeof(*tscadc), GFP_KERNEL);
> @@ -215,22 +215,21 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div);
>
> /* Set the control register bits */
> - ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID;
> - regmap_write(tscadc->regmap, REG_CTRL, ctrl);
> + tscadc->ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID;
> + regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl);
>
> if (tsc_wires > 0) {
> - tscadc->tsc_wires = tsc_wires;
> + tscadc->ctrl |= CNTRLREG_TSCENB;
> if (tsc_wires == 5)
> - ctrl |= CNTRLREG_5WIRE | CNTRLREG_TSCENB;
> + tscadc->ctrl |= CNTRLREG_5WIRE;
> else
> - ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB;
> + tscadc->ctrl |= CNTRLREG_4WIRE;
> }
>
> tscadc_idle_config(tscadc);
>
> /* Enable the TSC module enable bit */
> - ctrl |= CNTRLREG_TSCSSENB;
> - regmap_write(tscadc->regmap, REG_CTRL, ctrl);
> + regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_TSCSSENB);
>
> /* TSC Cell */
> if (tsc_wires > 0) {
> @@ -305,25 +304,13 @@ static int __maybe_unused tscadc_suspend(struct device *dev)
> static int __maybe_unused tscadc_resume(struct device *dev)
> {
> struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev);
> - u32 ctrl;
>
> pm_runtime_get_sync(dev);
>
> - /* context restore */
> - ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID;
> - regmap_write(tscadc->regmap, REG_CTRL, ctrl);
> -
> - if (tscadc->tsc_wires > 0) {
> - if (tscadc->tsc_wires == 5)
> - ctrl |= CNTRLREG_5WIRE | CNTRLREG_TSCENB;
> - else
> - ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB;
> - }
> - ctrl |= CNTRLREG_TSCSSENB;
> - regmap_write(tscadc->regmap, REG_CTRL, ctrl);
> -
> regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div);
> + regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl);
Patch description should mention why this ordering change is here.
> tscadc_idle_config(tscadc);
> + regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_TSCSSENB);
As the value of tscadc->ctrl is not the same as REG_CTRL this is a bit non obvious.
You might be better off keeping them in sync, but masking that bit out and then resetting
it as appropriate.
>
> return 0;
> }
> diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
> index e734fb97dff8..02963b6ebbac 100644
> --- a/include/linux/mfd/ti_am335x_tscadc.h
> +++ b/include/linux/mfd/ti_am335x_tscadc.h
> @@ -177,8 +177,8 @@ struct ti_tscadc_dev {
> phys_addr_t tscadc_phys_base;
> const struct ti_tscadc_data *data;
> int irq;
> - int tsc_wires;
> struct mfd_cell cells[TSCADC_CELLS];
> + u32 ctrl;
> u32 reg_se_cache;
> bool adc_waiting;
> bool adc_in_use;
