On Wed, 15 Sep 2021, Miquel Raynal wrote:
> Introduce a new compatible that has another set of driver data,
> targeting am437x SoCs with a magnetic reader instead of the
> touchscreen and a more featureful set of registers.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> drivers/mfd/ti_am335x_tscadc.c | 41 ++++++++++++++++++++++++----
> include/linux/mfd/ti_am335x_tscadc.h | 7 +++++
> 2 files changed, 42 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
> index 65c0fa735a71..155a8ed879b3 100644
> --- a/drivers/mfd/ti_am335x_tscadc.c
> +++ b/drivers/mfd/ti_am335x_tscadc.c
> @@ -121,11 +121,11 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> struct mfd_cell *cell;
> struct property *prop;
> const __be32 *cur;
> - bool use_tsc = false;
> + bool use_tsc = false, use_mag = false;
> u32 val;
> int err;
> int tscmag_wires = 0, adc_channels = 0, cell_idx = 0, total_channels;
> - int readouts = 0;
> + int readouts = 0, mag_tracks = 0;
>
> /* Allocate memory for device */
> tscadc = devm_kzalloc(&pdev->dev, sizeof(*tscadc), GFP_KERNEL);
> @@ -148,6 +148,16 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> of_node_put(node);
> if (tscmag_wires)
> use_tsc = true;
> + } else {
> + /*
> + * When adding support for the magnetic reader, here is the
> + * place to look for the number of tracks used from device tree.
> + * Let's default to 0 for now.
> + */
> + mag_tracks = 0;
> + tscmag_wires = mag_tracks * 2;
> + if (tscmag_wires)
> + use_mag = true;
> }
>
> node = of_get_child_by_name(pdev->dev.of_node, "adc");
> @@ -209,8 +219,9 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> * The TSC_ADC_Subsystem has 2 clock domains: OCP_CLK and ADC_CLK.
> * ADCs produce a 12-bit sample every 15 ADC_CLK cycles.
> * am33xx ADCs expect to capture 200ksps.
> - * We need the ADC clocks to run at 3MHz.
> - * This frequency is valid since TSC_ADC_SS controller design
> + * am47xx ADCs expect to capture 867ksps.
> + * We need ADC clocks respectively running at 3MHz and 13MHz.
> + * These frequencies are valid since TSC_ADC_SS controller design
> * assumes the OCP clock is at least 6x faster than the ADC clock.
> */
> clk = devm_clk_get(&pdev->dev, NULL);
> @@ -238,6 +249,9 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> else
> tscadc->ctrl |= CNTRLREG_TSC_4WIRE;
> }
> + } else {
> + tscadc->ctrl |= CNTRLREG_MAG_PREAMP_PWRDOWN |
> + CNTRLREG_MAG_PREAMP_BYPASS;
> }
> regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl);
>
> @@ -246,7 +260,7 @@ static int ti_tscadc_probe(struct platform_device *pdev)
> /* Enable the TSC module enable bit */
> regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_SSENB);
>
> - /* TSC Cell */
> + /* TSC or MAG Cell */
> if (tscmag_wires > 0) {
> cell = &tscadc->cells[cell_idx++];
> cell->name = tscadc->data->name_tscmag;
> @@ -334,6 +348,7 @@ static SIMPLE_DEV_PM_OPS(tscadc_pm_ops, tscadc_suspend, tscadc_resume);
>
> static const struct ti_tscadc_data tscdata = {
> .has_tsc = true,
> + .has_mag = false,
> .name_tscmag = "TI-am335x-tsc",
> .compat_tscmag = "ti,am3359-tsc",
> .name_adc = "TI-am335x-adc",
> @@ -341,11 +356,25 @@ static const struct ti_tscadc_data tscdata = {
> .target_clk_rate = TSC_ADC_CLK,
> };
>
> +static const struct ti_tscadc_data magdata = {
> + .has_tsc = false,
> + .has_mag = true,
Why 2 bools?
Better to have a single u8:
MODE_TOUCHSCREEN
MODE_MAG_STRING
MODE_NONE
> + .name_tscmag = "TI-am43xx-mag",
> + .compat_tscmag = "ti,am4372-mag",
> + .name_adc = "TI-am43xx-adc",
> + .compat_adc = "ti,am4372-adc",
> + .target_clk_rate = MAG_ADC_CLK,
> +};
> +
> static const struct of_device_id ti_tscadc_dt_ids[] = {
> {
> .compatible = "ti,am3359-tscadc",
> .data = &tscdata,
> },
> + {
> + .compatible = "ti,am4372-magadc",
> + .data = &magdata,
> + },
> { }
> };
> MODULE_DEVICE_TABLE(of, ti_tscadc_dt_ids);
> @@ -363,6 +392,6 @@ static struct platform_driver ti_tscadc_driver = {
>
> module_platform_driver(ti_tscadc_driver);
>
> -MODULE_DESCRIPTION("TI touchscreen / ADC MFD controller driver");
> +MODULE_DESCRIPTION("TI touchscreen/magnetic reader/ADC MFD controller driver");
Magnetic what? Tape, disk, stripe?
> MODULE_AUTHOR("Rachna Patil <rachna@xxxxxx>");
> MODULE_LICENSE("GPL");
> diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
> index 467b3bec4335..9a412e6d764b 100644
> --- a/include/linux/mfd/ti_am335x_tscadc.h
> +++ b/include/linux/mfd/ti_am335x_tscadc.h
> @@ -106,6 +106,11 @@
> #define CNTRLREG_TSC_8WIRE CNTRLREG_TSC_AFE_CTRL(3)
> #define CNTRLREG_TSC_ENB BIT(7)
>
> +/*Control registers bitfields for MAGADC IP */
> +#define CNTRLREG_MAGADCENB BIT(0)
> +#define CNTRLREG_MAG_PREAMP_PWRDOWN BIT(5)
> +#define CNTRLREG_MAG_PREAMP_BYPASS BIT(6)
> +
> /* FIFO READ Register */
> #define FIFOREAD_DATA_MASK GENMASK(11, 0)
> #define FIFOREAD_CHNLID_MASK GENMASK(19, 16)
> @@ -119,6 +124,7 @@
> #define CHARGE_STEP 0x11
>
> #define TSC_ADC_CLK (3 * HZ_PER_MHZ)
> +#define MAG_ADC_CLK (13 * HZ_PER_MHZ)
> #define TOTAL_STEPS 16
> #define TOTAL_CHANNELS 8
> #define FIFO1_THRESHOLD 19
> @@ -141,6 +147,7 @@
>
> struct ti_tscadc_data {
> bool has_tsc;
> + bool has_mag;
> char *name_tscmag;
> char *compat_tscmag;
> char *name_adc;
--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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