diff mbox series

[v3,35/47] mfd: ti_am335x_tscadc: Add ADC1/magnetic reader support

Message ID 20210915155908.476767-36-miquel.raynal@bootlin.com
State New
Headers show
Series TI AM437X ADC1 | expand

Commit Message

Miquel Raynal Sept. 15, 2021, 3:58 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>
---
 drivers/mfd/ti_am335x_tscadc.c       | 41 ++++++++++++++++++++++++----
 include/linux/mfd/ti_am335x_tscadc.h |  7 +++++
 2 files changed, 42 insertions(+), 6 deletions(-)

Comments

Miquel Raynal Sept. 23, 2021, 8:33 a.m. UTC | #1
Hi Lee,

lee.jones@linaro.org wrote on Wed, 22 Sep 2021 17:00:20 +0100:

> 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@bootlin.com>

> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> > ---

> >  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


It's not a mode like "please use this feature", it is more like a
feature that is present and we need to know which one it is.

Anyway, I can use an enum for this, fine.

> 

> > +	.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?


I guess my current knowledge of English tricked me as I thought
"magnetic reader" was clear enough for everybody, but I'll make the
commit logs and this module description clearer by specifying the
"stripe" keyword, sure.
 
> 

> >  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 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;  

> 



Thanks,
Miquèl
diff mbox series

Patch

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,
+	.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");
 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 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;