diff mbox series

[v2,2/2] staging: iio: cdc: ad7746: use dt for capacitive channel setup.

Message ID b0132613b82b17d63c8a91556c2c424015f202db.1618785336.git.lucas.p.stankus@gmail.com (mailing list archive)
State New, archived
Headers show
Series staging: iio: cdc: ad7746: add dt properties for capacitive channel setup | expand

Commit Message

Lucas Stankus April 18, 2021, 10:50 p.m. UTC 
Ditch platform_data fields in favor of device tree properties for
configuring EXCA and EXCB output pins and setting the capacitive channel
excitation level.

As this covers all current use cases for the platform_data struct, remove
ad7746.h header file since it's no longer needed.

Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
---

Changes in v2:
Previously this change set was composed of two patches, but it lead to
regressions between the two. Merging them avoids the unwanted behaviour
without having to deal with the special cases.

 drivers/staging/iio/cdc/ad7746.c | 42 +++++++++++++++-----------------
 drivers/staging/iio/cdc/ad7746.h | 28 ---------------------
 2 files changed, 19 insertions(+), 51 deletions(-)
 delete mode 100644 drivers/staging/iio/cdc/ad7746.h

Comments

Jonathan Cameron April 24, 2021, 12:11 p.m. UTC | #1 
On Sun, 18 Apr 2021 19:50:10 -0300
Lucas Stankus <lucas.p.stankus@gmail.com> wrote:

> Ditch platform_data fields in favor of device tree properties for
> configuring EXCA and EXCB output pins and setting the capacitive channel
> excitation level.
> 
> As this covers all current use cases for the platform_data struct, remove
> ad7746.h header file since it's no longer needed.
> 
> Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
Hi Lucas,

Just one comment which is that the permille to register value
is a bit opaque so I think I'd prefer a simple lookup table even though it
is a bit more code.

Otherwise looks good to me.

Thanks,

Jonathan
> ---
> 
> Changes in v2:
> Previously this change set was composed of two patches, but it lead to
> regressions between the two. Merging them avoids the unwanted behaviour
> without having to deal with the special cases.
> 
>  drivers/staging/iio/cdc/ad7746.c | 42 +++++++++++++++-----------------
>  drivers/staging/iio/cdc/ad7746.h | 28 ---------------------
>  2 files changed, 19 insertions(+), 51 deletions(-)
>  delete mode 100644 drivers/staging/iio/cdc/ad7746.h
> 
> diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
> index dfd71e99e872..c0e84c1cf4f1 100644
> --- a/drivers/staging/iio/cdc/ad7746.c
> +++ b/drivers/staging/iio/cdc/ad7746.c
> @@ -18,8 +18,6 @@
>  #include <linux/iio/iio.h>
>  #include <linux/iio/sysfs.h>
>  
> -#include "ad7746.h"
> -
>  /*
>   * AD7746 Register Definition
>   */
> @@ -66,7 +64,7 @@
>  #define AD7746_EXCSETUP_NEXCB		BIT(4)
>  #define AD7746_EXCSETUP_EXCA		BIT(3)
>  #define AD7746_EXCSETUP_NEXCA		BIT(2)
> -#define AD7746_EXCSETUP_EXCLVL(x)	(((x) & 0x3) << 0)
> +#define AD7746_EXCSETUP_EXCLVL(x)	(((x) >> 7) & 0x3)

I'd like a comment on this maths, or just use a lookup table instead so
we don't have to think about it and also enforce exact matches.
The rounding this results in is a bit odd

>  
>  /* Config Register Bit Designations (AD7746_REG_CFG) */
>  #define AD7746_CONF_VTFS_SHIFT		6
> @@ -676,10 +674,11 @@ static const struct iio_info ad7746_info = {
>  static int ad7746_probe(struct i2c_client *client,
>  			const struct i2c_device_id *id)
>  {
> -	struct ad7746_platform_data *pdata = client->dev.platform_data;
> +	struct device *dev = &client->dev;
>  	struct ad7746_chip_info *chip;
>  	struct iio_dev *indio_dev;
>  	unsigned char regval = 0;
> +	unsigned int vdd_permille;
>  	int ret = 0;
>  
>  	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
> @@ -703,28 +702,25 @@ static int ad7746_probe(struct i2c_client *client,
>  	indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  
> -	if (pdata) {
> -		if (pdata->exca_en) {
> -			if (pdata->exca_inv_en)
> -				regval |= AD7746_EXCSETUP_NEXCA;
> -			else
> -				regval |= AD7746_EXCSETUP_EXCA;
> -		}
> -
> -		if (pdata->excb_en) {
> -			if (pdata->excb_inv_en)
> -				regval |= AD7746_EXCSETUP_NEXCB;
> -			else
> -				regval |= AD7746_EXCSETUP_EXCB;
> -		}
> +	if (device_property_read_bool(dev, "adi,exca-output-en")) {
> +		if (device_property_read_bool(dev, "adi,exca-output-invert"))
> +			regval |= AD7746_EXCSETUP_NEXCA;
> +		else
> +			regval |= AD7746_EXCSETUP_EXCA;
> +	}
>  
> -		regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
> -	} else {
> -		dev_warn(&client->dev, "No platform data? using default\n");
> -		regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
> -			AD7746_EXCSETUP_EXCLVL(3);
> +	if (device_property_read_bool(dev, "adi,excb-output-en")) {
> +		if (device_property_read_bool(dev, "adi,excb-output-invert"))
> +			regval |= AD7746_EXCSETUP_NEXCB;
> +		else
> +			regval |= AD7746_EXCSETUP_EXCB;
>  	}
>  
> +	ret = device_property_read_u32(dev, "adi,excitation-vdd-permille",
> +				       &vdd_permille);
> +	if (!ret)
> +		regval |= AD7746_EXCSETUP_EXCLVL(vdd_permille);
> +
>  	ret = i2c_smbus_write_byte_data(chip->client,
>  					AD7746_REG_EXC_SETUP, regval);
>  	if (ret < 0)
> diff --git a/drivers/staging/iio/cdc/ad7746.h b/drivers/staging/iio/cdc/ad7746.h
> deleted file mode 100644
> index 8bdbd732dbbd..000000000000
> --- a/drivers/staging/iio/cdc/ad7746.h
> +++ /dev/null
> @@ -1,28 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0 */
> -/*
> - * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
> - *
> - * Copyright 2011 Analog Devices Inc.
> - */
> -
> -#ifndef IIO_CDC_AD7746_H_
> -#define IIO_CDC_AD7746_H_
> -
> -/*
> - * TODO: struct ad7746_platform_data needs to go into include/linux/iio
> - */
> -
> -#define AD7466_EXCLVL_0		0 /* +-VDD/8 */
> -#define AD7466_EXCLVL_1		1 /* +-VDD/4 */
> -#define AD7466_EXCLVL_2		2 /* +-VDD * 3/8 */
> -#define AD7466_EXCLVL_3		3 /* +-VDD/2 */
> -
> -struct ad7746_platform_data {
> -	unsigned char exclvl;	/*Excitation Voltage Level */
> -	bool exca_en;		/* enables EXCA pin as the excitation output */
> -	bool exca_inv_en;	/* enables /EXCA pin as the excitation output */
> -	bool excb_en;		/* enables EXCB pin as the excitation output */
> -	bool excb_inv_en;	/* enables /EXCB pin as the excitation output */
> -};
> -
> -#endif /* IIO_CDC_AD7746_H_ */
Lucas Stankus April 26, 2021, 12:54 a.m. UTC | #2 
On Sat, Apr 24, 2021 at 9:10 AM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Sun, 18 Apr 2021 19:50:10 -0300
> Lucas Stankus <lucas.p.stankus@gmail.com> wrote:
>
> > Ditch platform_data fields in favor of device tree properties for
> > configuring EXCA and EXCB output pins and setting the capacitive channel
> > excitation level.
> >
> > As this covers all current use cases for the platform_data struct, remove
> > ad7746.h header file since it's no longer needed.
> >
> > Signed-off-by: Lucas Stankus <lucas.p.stankus@gmail.com>
> Hi Lucas,
>
> Just one comment which is that the permille to register value
> is a bit opaque so I think I'd prefer a simple lookup table even though it
> is a bit more code.
>
> Otherwise looks good to me.
>
> Thanks,
>
> Jonathan

Thank you!

> > ---
> >
> > Changes in v2:
> > Previously this change set was composed of two patches, but it lead to
> > regressions between the two. Merging them avoids the unwanted behaviour
> > without having to deal with the special cases.
> >
> >  drivers/staging/iio/cdc/ad7746.c | 42 +++++++++++++++-----------------
> >  drivers/staging/iio/cdc/ad7746.h | 28 ---------------------
> >  2 files changed, 19 insertions(+), 51 deletions(-)
> >  delete mode 100644 drivers/staging/iio/cdc/ad7746.h
> >
> > diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
> > index dfd71e99e872..c0e84c1cf4f1 100644
> > --- a/drivers/staging/iio/cdc/ad7746.c
> > +++ b/drivers/staging/iio/cdc/ad7746.c
> > @@ -18,8 +18,6 @@
> >  #include <linux/iio/iio.h>
> >  #include <linux/iio/sysfs.h>
> >
> > -#include "ad7746.h"
> > -
> >  /*
> >   * AD7746 Register Definition
> >   */
> > @@ -66,7 +64,7 @@
> >  #define AD7746_EXCSETUP_NEXCB                BIT(4)
> >  #define AD7746_EXCSETUP_EXCA         BIT(3)
> >  #define AD7746_EXCSETUP_NEXCA                BIT(2)
> > -#define AD7746_EXCSETUP_EXCLVL(x)    (((x) & 0x3) << 0)
> > +#define AD7746_EXCSETUP_EXCLVL(x)    (((x) >> 7) & 0x3)
>
> I'd like a comment on this maths, or just use a lookup table instead so
> we don't have to think about it and also enforce exact matches.
> The rounding this results in is a bit odd

To be fair this macro is a bit hack-ish, the permille binding can be 125, 250,
500 or 750, so dividing it by 128 maps these values from 0 to 3, which are the
expected numbers for configuring the device.

I decided to use the bit shift because it was more concise than a lookup table,
but the latter might be more legible, I'll send a v3 with one instead.

>
> >
> >  /* Config Register Bit Designations (AD7746_REG_CFG) */
> >  #define AD7746_CONF_VTFS_SHIFT               6
> > @@ -676,10 +674,11 @@ static const struct iio_info ad7746_info = {
> >  static int ad7746_probe(struct i2c_client *client,
> >                       const struct i2c_device_id *id)
> >  {
> > -     struct ad7746_platform_data *pdata = client->dev.platform_data;
> > +     struct device *dev = &client->dev;
> >       struct ad7746_chip_info *chip;
> >       struct iio_dev *indio_dev;
> >       unsigned char regval = 0;
> > +     unsigned int vdd_permille;
> >       int ret = 0;
> >
> >       indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
> > @@ -703,28 +702,25 @@ static int ad7746_probe(struct i2c_client *client,
> >       indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
> >       indio_dev->modes = INDIO_DIRECT_MODE;
> >
> > -     if (pdata) {
> > -             if (pdata->exca_en) {
> > -                     if (pdata->exca_inv_en)
> > -                             regval |= AD7746_EXCSETUP_NEXCA;
> > -                     else
> > -                             regval |= AD7746_EXCSETUP_EXCA;
> > -             }
> > -
> > -             if (pdata->excb_en) {
> > -                     if (pdata->excb_inv_en)
> > -                             regval |= AD7746_EXCSETUP_NEXCB;
> > -                     else
> > -                             regval |= AD7746_EXCSETUP_EXCB;
> > -             }
> > +     if (device_property_read_bool(dev, "adi,exca-output-en")) {
> > +             if (device_property_read_bool(dev, "adi,exca-output-invert"))
> > +                     regval |= AD7746_EXCSETUP_NEXCA;
> > +             else
> > +                     regval |= AD7746_EXCSETUP_EXCA;
> > +     }
> >
> > -             regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
> > -     } else {
> > -             dev_warn(&client->dev, "No platform data? using default\n");
> > -             regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
> > -                     AD7746_EXCSETUP_EXCLVL(3);
> > +     if (device_property_read_bool(dev, "adi,excb-output-en")) {
> > +             if (device_property_read_bool(dev, "adi,excb-output-invert"))
> > +                     regval |= AD7746_EXCSETUP_NEXCB;
> > +             else
> > +                     regval |= AD7746_EXCSETUP_EXCB;
> >       }
> >
> > +     ret = device_property_read_u32(dev, "adi,excitation-vdd-permille",
> > +                                    &vdd_permille);
> > +     if (!ret)
> > +             regval |= AD7746_EXCSETUP_EXCLVL(vdd_permille);
> > +
> >       ret = i2c_smbus_write_byte_data(chip->client,
> >                                       AD7746_REG_EXC_SETUP, regval);
> >       if (ret < 0)
> > diff --git a/drivers/staging/iio/cdc/ad7746.h b/drivers/staging/iio/cdc/ad7746.h
> > deleted file mode 100644
> > index 8bdbd732dbbd..000000000000
> > --- a/drivers/staging/iio/cdc/ad7746.h
> > +++ /dev/null
> > @@ -1,28 +0,0 @@
> > -/* SPDX-License-Identifier: GPL-2.0 */
> > -/*
> > - * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
> > - *
> > - * Copyright 2011 Analog Devices Inc.
> > - */
> > -
> > -#ifndef IIO_CDC_AD7746_H_
> > -#define IIO_CDC_AD7746_H_
> > -
> > -/*
> > - * TODO: struct ad7746_platform_data needs to go into include/linux/iio
> > - */
> > -
> > -#define AD7466_EXCLVL_0              0 /* +-VDD/8 */
> > -#define AD7466_EXCLVL_1              1 /* +-VDD/4 */
> > -#define AD7466_EXCLVL_2              2 /* +-VDD * 3/8 */
> > -#define AD7466_EXCLVL_3              3 /* +-VDD/2 */
> > -
> > -struct ad7746_platform_data {
> > -     unsigned char exclvl;   /*Excitation Voltage Level */
> > -     bool exca_en;           /* enables EXCA pin as the excitation output */
> > -     bool exca_inv_en;       /* enables /EXCA pin as the excitation output */
> > -     bool excb_en;           /* enables EXCB pin as the excitation output */
> > -     bool excb_inv_en;       /* enables /EXCB pin as the excitation output */
> > -};
> > -
> > -#endif /* IIO_CDC_AD7746_H_ */
>
diff mbox series

Patch

diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
index dfd71e99e872..c0e84c1cf4f1 100644
--- a/drivers/staging/iio/cdc/ad7746.c
+++ b/drivers/staging/iio/cdc/ad7746.c
@@ -18,8 +18,6 @@ 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 
-#include "ad7746.h"
-
 /*
  * AD7746 Register Definition
  */
@@ -66,7 +64,7 @@ 
 #define AD7746_EXCSETUP_NEXCB		BIT(4)
 #define AD7746_EXCSETUP_EXCA		BIT(3)
 #define AD7746_EXCSETUP_NEXCA		BIT(2)
-#define AD7746_EXCSETUP_EXCLVL(x)	(((x) & 0x3) << 0)
+#define AD7746_EXCSETUP_EXCLVL(x)	(((x) >> 7) & 0x3)
 
 /* Config Register Bit Designations (AD7746_REG_CFG) */
 #define AD7746_CONF_VTFS_SHIFT		6
@@ -676,10 +674,11 @@  static const struct iio_info ad7746_info = {
 static int ad7746_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
-	struct ad7746_platform_data *pdata = client->dev.platform_data;
+	struct device *dev = &client->dev;
 	struct ad7746_chip_info *chip;
 	struct iio_dev *indio_dev;
 	unsigned char regval = 0;
+	unsigned int vdd_permille;
 	int ret = 0;
 
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
@@ -703,28 +702,25 @@  static int ad7746_probe(struct i2c_client *client,
 	indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
-	if (pdata) {
-		if (pdata->exca_en) {
-			if (pdata->exca_inv_en)
-				regval |= AD7746_EXCSETUP_NEXCA;
-			else
-				regval |= AD7746_EXCSETUP_EXCA;
-		}
-
-		if (pdata->excb_en) {
-			if (pdata->excb_inv_en)
-				regval |= AD7746_EXCSETUP_NEXCB;
-			else
-				regval |= AD7746_EXCSETUP_EXCB;
-		}
+	if (device_property_read_bool(dev, "adi,exca-output-en")) {
+		if (device_property_read_bool(dev, "adi,exca-output-invert"))
+			regval |= AD7746_EXCSETUP_NEXCA;
+		else
+			regval |= AD7746_EXCSETUP_EXCA;
+	}
 
-		regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
-	} else {
-		dev_warn(&client->dev, "No platform data? using default\n");
-		regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
-			AD7746_EXCSETUP_EXCLVL(3);
+	if (device_property_read_bool(dev, "adi,excb-output-en")) {
+		if (device_property_read_bool(dev, "adi,excb-output-invert"))
+			regval |= AD7746_EXCSETUP_NEXCB;
+		else
+			regval |= AD7746_EXCSETUP_EXCB;
 	}
 
+	ret = device_property_read_u32(dev, "adi,excitation-vdd-permille",
+				       &vdd_permille);
+	if (!ret)
+		regval |= AD7746_EXCSETUP_EXCLVL(vdd_permille);
+
 	ret = i2c_smbus_write_byte_data(chip->client,
 					AD7746_REG_EXC_SETUP, regval);
 	if (ret < 0)
diff --git a/drivers/staging/iio/cdc/ad7746.h b/drivers/staging/iio/cdc/ad7746.h
deleted file mode 100644
index 8bdbd732dbbd..000000000000
--- a/drivers/staging/iio/cdc/ad7746.h
+++ /dev/null
@@ -1,28 +0,0 @@ 
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
- *
- * Copyright 2011 Analog Devices Inc.
- */
-
-#ifndef IIO_CDC_AD7746_H_
-#define IIO_CDC_AD7746_H_
-
-/*
- * TODO: struct ad7746_platform_data needs to go into include/linux/iio
- */
-
-#define AD7466_EXCLVL_0		0 /* +-VDD/8 */
-#define AD7466_EXCLVL_1		1 /* +-VDD/4 */
-#define AD7466_EXCLVL_2		2 /* +-VDD * 3/8 */
-#define AD7466_EXCLVL_3		3 /* +-VDD/2 */
-
-struct ad7746_platform_data {
-	unsigned char exclvl;	/*Excitation Voltage Level */
-	bool exca_en;		/* enables EXCA pin as the excitation output */
-	bool exca_inv_en;	/* enables /EXCA pin as the excitation output */
-	bool excb_en;		/* enables EXCB pin as the excitation output */
-	bool excb_inv_en;	/* enables /EXCB pin as the excitation output */
-};
-
-#endif /* IIO_CDC_AD7746_H_ */