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

Lee Jones Sept. 22, 2021, 4 p.m. UTC | #1
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

> +	.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@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;


-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog
Miquel Raynal Sept. 28, 2021, 10:34 a.m. UTC | #2
Hi Lee,

> >  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


I was about to add an enum for these but actually it is totally
redundant with the compatible name. Instead, I have added a
helper which checks the compatible string and gives the same
information.

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;