diff mbox series

[v5] mfd: ti_am335x_tscadc: Add ADC1/magnetic reader support

Message ID 20211004155319.1507652-1-miquel.raynal@bootlin.com (mailing list archive)
State Not Applicable
Headers show
Series [v5] mfd: ti_am335x_tscadc: Add ADC1/magnetic reader support | expand

Commit Message

Miquel Raynal Oct. 4, 2021, 3:53 p.m. UTC
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@bootlin.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---

Changes in v5:
* Let the 48 v4 patch series aside, while only resending this patch that
  triggered a robot warning. Use the use_mag boolean instead of sticking
  to tscmag_wires which was not optimal anyway, silencing the 'not used'
  warning while keeping the code simple and clear.


 drivers/mfd/ti_am335x_tscadc.c       | 37 ++++++++++++++++++++++------
 include/linux/mfd/ti_am335x_tscadc.h |  6 +++++
 2 files changed, 36 insertions(+), 7 deletions(-)

Comments

Lee Jones Oct. 12, 2021, 10:56 a.m. UTC | #1
On Mon, 04 Oct 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@bootlin.com>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
> 
> Changes in v5:
> * Let the 48 v4 patch series aside, while only resending this patch that
>   triggered a robot warning. Use the use_mag boolean instead of sticking
>   to tscmag_wires which was not optimal anyway, silencing the 'not used'
>   warning while keeping the code simple and clear.
> 
> 
>  drivers/mfd/ti_am335x_tscadc.c       | 37 ++++++++++++++++++++++------
>  include/linux/mfd/ti_am335x_tscadc.h |  6 +++++
>  2 files changed, 36 insertions(+), 7 deletions(-)

Okay, so I've been battling with this set for a while.  I've finally
managed to figure out how to apply the whole set including this
straggler, but Patch 10 is not applying to my tree.  Could you please
rebase and resend the whole set with this one included please?
diff mbox series

Patch

diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
index 4f76b5498077..bfbc8288a71e 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 stripe 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);
 
@@ -246,8 +260,8 @@  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 */
-	if (tscmag_wires > 0) {
+	/* TSC or MAG Cell */
+	if (use_tsc || use_mag) {
 		cell = &tscadc->cells[cell_idx++];
 		cell->name = tscadc->data->secondary_feature_name;
 		cell->of_compatible = tscadc->data->secondary_feature_compatible;
@@ -340,8 +354,17 @@  static const struct ti_tscadc_data tscdata = {
 	.target_clk_rate = TSC_ADC_CLK,
 };
 
+static const struct ti_tscadc_data magdata = {
+	.adc_feature_name = "TI-am43xx-adc",
+	.adc_feature_compatible = "ti,am4372-adc",
+	.secondary_feature_name = "TI-am43xx-mag",
+	.secondary_feature_compatible = "ti,am4372-mag",
+	.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);
@@ -359,6 +382,6 @@  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 stripe reader/ADC MFD controller driver");
 MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
 MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/ti_am335x_tscadc.h b/include/linux/mfd/ti_am335x_tscadc.h
index ee160b2036c1..5225e3fc194d 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