[PATCH 1/2] staging:iio:ad7780: Make powerdown GPIO optional

[PATCH 1/2] staging:iio:ad7780: Make powerdown GPIO optional

[Lars-Peter Clausen]

Some designs hardwire the PDRST pin to always on. In this case there is no GPIO
to control the mode of the device, so make the GPIO optional. Since now all of
the the platform data fields are optional now, make the platform data as a whole
optional as well.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/iio/adc/ad7780.c |   31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
index 5f807ce..1dd7cdb 100644
--- a/drivers/staging/iio/adc/ad7780.c
+++ b/drivers/staging/iio/adc/ad7780.c
@@ -73,7 +73,8 @@ static int ad7780_set_mode(struct ad_sigma_delta *sigma_delta,
 		break;
 	}
 
-	gpio_set_value(st->powerdown_gpio, val);
+	if (gpio_is_valid(st->powerdown_gpio))
+		gpio_set_value(st->powerdown_gpio, val);
 
 	return 0;
 }
@@ -148,11 +149,6 @@ static int __devinit ad7780_probe(struct spi_device *spi)
 	struct iio_dev *indio_dev;
 	int ret, voltage_uv = 0;
 
-	if (!pdata) {
-		dev_dbg(&spi->dev, "no platform data?\n");
-		return -ENODEV;
-	}
-
 	indio_dev = iio_device_alloc(sizeof(*st));
 	if (indio_dev == NULL)
 		return -ENOMEM;
@@ -174,8 +170,6 @@ static int __devinit ad7780_probe(struct spi_device *spi)
 	st->chip_info =
 		&ad7780_chip_info_tbl[spi_get_device_id(spi)->driver_data];
 
-	st->powerdown_gpio = pdata->gpio_pdrst;
-
 	if (pdata && pdata->vref_mv)
 		st->int_vref_mv = pdata->vref_mv;
 	else if (voltage_uv)
@@ -192,11 +186,17 @@ static int __devinit ad7780_probe(struct spi_device *spi)
 	indio_dev->num_channels = 1;
 	indio_dev->info = &ad7780_info;
 
-	ret = gpio_request_one(pdata->gpio_pdrst, GPIOF_OUT_INIT_LOW,
+	if (pdata && gpio_is_valid(pdata->gpio_pdrst)) {
+
+		ret = gpio_request_one(pdata->gpio_pdrst, GPIOF_OUT_INIT_LOW,
 			       "AD7780 /PDRST");
-	if (ret) {
-		dev_err(&spi->dev, "failed to request GPIO PDRST\n");
-		goto error_disable_reg;
+		if (ret) {
+			dev_err(&spi->dev, "failed to request GPIO PDRST\n");
+			goto error_disable_reg;
+		}
+		st->powerdown_gpio = pdata->gpio_pdrst;
+	} else {
+		st->powerdown_gpio = -1;
 	}
 
 	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
@@ -212,7 +212,8 @@ static int __devinit ad7780_probe(struct spi_device *spi)
 error_cleanup_buffer_and_trigger:
 	ad_sd_cleanup_buffer_and_trigger(indio_dev);
 error_free_gpio:
-	gpio_free(pdata->gpio_pdrst);
+	if (pdata && gpio_is_valid(pdata->gpio_pdrst))
+		gpio_free(pdata->gpio_pdrst);
 error_disable_reg:
 	if (!IS_ERR(st->reg))
 		regulator_disable(st->reg);
@@ -233,7 +234,9 @@ static int __devexit ad7780_remove(struct spi_device *spi)
 	iio_device_unregister(indio_dev);
 	ad_sd_cleanup_buffer_and_trigger(indio_dev);
 
-	gpio_free(st->powerdown_gpio);
+	if (gpio_is_valid(st->powerdown_gpio))
+		gpio_free(st->powerdown_gpio);
+
 	if (!IS_ERR(st->reg)) {
 		regulator_disable(st->reg);
 		regulator_put(st->reg);
-- 
1.7.10.4

[PATCH 2/2] staging:iio:ad7780: Add support for the ad7170/ad7171

[Lars-Peter Clausen]

The ad7170/ad7171 have a software interface similar to the ad7780. They do not
have an external pin which allows to change the internal gain and the what is
used for the gain bit in the ad7780/ad7781 becomes part of the check pattern.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 drivers/staging/iio/adc/Kconfig  |    4 ++--
 drivers/staging/iio/adc/ad7780.c |   36 ++++++++++++++++++++++++++++++------
 2 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index 1b4a356..a525143 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -82,12 +82,12 @@ config AD7887
 	  module will be called ad7887.
 
 config AD7780
-	tristate "Analog Devices AD7780 AD7781 ADC driver"
+	tristate "Analog Devices AD7780 and similar ADCs driver"
 	depends on SPI
 	depends on GPIOLIB
 	select AD_SIGMA_DELTA
 	help
-	  Say yes here to build support for Analog Devices
+	  Say yes here to build support for Analog Devices AD7170, AD7171,
 	  AD7780 and AD7781 SPI analog to digital converters (ADC).
 	  If unsure, say N (but it's safe to say "Y").
 
diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
index 1dd7cdb..0a1328b 100644
--- a/drivers/staging/iio/adc/ad7780.c
+++ b/drivers/staging/iio/adc/ad7780.c
@@ -1,5 +1,5 @@
 /*
- * AD7780/AD7781 SPI ADC driver
+ * AD7170/AD7171 and AD7780/AD7781 SPI ADC driver
  *
  * Copyright 2011 Analog Devices Inc.
  *
@@ -34,7 +34,9 @@
 #define AD7780_PAT0	(1 << 0)
 
 struct ad7780_chip_info {
-	struct iio_chan_spec		channel;
+	struct iio_chan_spec	channel;
+	unsigned int		pattern_mask;
+	unsigned int		pattern;
 };
 
 struct ad7780_state {
@@ -48,6 +50,8 @@ struct ad7780_state {
 };
 
 enum ad7780_supported_device_ids {
+	ID_AD7170,
+	ID_AD7171,
 	ID_AD7780,
 	ID_AD7781,
 };
@@ -109,9 +113,10 @@ static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
 	unsigned int raw_sample)
 {
 	struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta);
+	const struct ad7780_chip_info *chip_info = st->chip_info;
 
 	if ((raw_sample & AD7780_ERR) ||
-		!((raw_sample & AD7780_PAT0) && !(raw_sample & AD7780_PAT1)))
+		((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
 		return -EIO;
 
 	if (raw_sample & AD7780_GAIN)
@@ -128,12 +133,29 @@ static const struct ad_sigma_delta_info ad7780_sigma_delta_info = {
 	.has_registers = false,
 };
 
+#define AD7780_CHANNEL(bits, wordsize) \
+	AD_SD_CHANNEL(1, 0, 0, bits, 32, wordsize - bits)
+
 static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
+	[ID_AD7170] = {
+		.channel = AD7780_CHANNEL(12, 24),
+		.pattern = 0x5,
+		.pattern_mask = 0x7,
+	},
+	[ID_AD7171] = {
+		.channel = AD7780_CHANNEL(16, 24),
+		.pattern = 0x5,
+		.pattern_mask = 0x7,
+	},
 	[ID_AD7780] = {
-		.channel = AD_SD_CHANNEL(1, 0, 0, 24, 32, 8),
+		.channel = AD7780_CHANNEL(24, 32),
+		.pattern = 0x1,
+		.pattern_mask = 0x3,
 	},
 	[ID_AD7781] = {
-		.channel = AD_SD_CHANNEL(1, 0, 0, 20, 32, 12),
+		.channel = AD7780_CHANNEL(20, 32),
+		.pattern = 0x1,
+		.pattern_mask = 0x3,
 	},
 };
 
@@ -247,6 +269,8 @@ static int __devexit ad7780_remove(struct spi_device *spi)
 }
 
 static const struct spi_device_id ad7780_id[] = {
+	{"ad7170", ID_AD7170},
+	{"ad7171", ID_AD7171},
 	{"ad7780", ID_AD7780},
 	{"ad7781", ID_AD7781},
 	{}
@@ -265,5 +289,5 @@ static struct spi_driver ad7780_driver = {
 module_spi_driver(ad7780_driver);
 
 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
-MODULE_DESCRIPTION("Analog Devices AD7780/1 ADC");
+MODULE_DESCRIPTION("Analog Devices AD7780 and similar ADCs");
 MODULE_LICENSE("GPL v2");
-- 
1.7.10.4

Re: [PATCH 1/2] staging:iio:ad7780: Make powerdown GPIO optional

[Jonathan Cameron]

On 09/21/2012 02:29 PM, Lars-Peter Clausen wrote:
> Some designs hardwire the PDRST pin to always on. In this case there is no GPIO
> to control the mode of the device, so make the GPIO optional. Since now all of
> the the platform data fields are optional now, make the platform data as a whole
> optional as well.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
added to togreg branch of iio.git
> ---
>  drivers/staging/iio/adc/ad7780.c |   31 +++++++++++++++++--------------
>  1 file changed, 17 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
> index 5f807ce..1dd7cdb 100644
> --- a/drivers/staging/iio/adc/ad7780.c
> +++ b/drivers/staging/iio/adc/ad7780.c
> @@ -73,7 +73,8 @@ static int ad7780_set_mode(struct ad_sigma_delta *sigma_delta,
>  		break;
>  	}
>  
> -	gpio_set_value(st->powerdown_gpio, val);
> +	if (gpio_is_valid(st->powerdown_gpio))
> +		gpio_set_value(st->powerdown_gpio, val);
>  
>  	return 0;
>  }
> @@ -148,11 +149,6 @@ static int __devinit ad7780_probe(struct spi_device *spi)
>  	struct iio_dev *indio_dev;
>  	int ret, voltage_uv = 0;
>  
> -	if (!pdata) {
> -		dev_dbg(&spi->dev, "no platform data?\n");
> -		return -ENODEV;
> -	}
> -
>  	indio_dev = iio_device_alloc(sizeof(*st));
>  	if (indio_dev == NULL)
>  		return -ENOMEM;
> @@ -174,8 +170,6 @@ static int __devinit ad7780_probe(struct spi_device *spi)
>  	st->chip_info =
>  		&ad7780_chip_info_tbl[spi_get_device_id(spi)->driver_data];
>  
> -	st->powerdown_gpio = pdata->gpio_pdrst;
> -
>  	if (pdata && pdata->vref_mv)
>  		st->int_vref_mv = pdata->vref_mv;
>  	else if (voltage_uv)
> @@ -192,11 +186,17 @@ static int __devinit ad7780_probe(struct spi_device *spi)
>  	indio_dev->num_channels = 1;
>  	indio_dev->info = &ad7780_info;
>  
> -	ret = gpio_request_one(pdata->gpio_pdrst, GPIOF_OUT_INIT_LOW,
> +	if (pdata && gpio_is_valid(pdata->gpio_pdrst)) {
> +
> +		ret = gpio_request_one(pdata->gpio_pdrst, GPIOF_OUT_INIT_LOW,
>  			       "AD7780 /PDRST");
> -	if (ret) {
> -		dev_err(&spi->dev, "failed to request GPIO PDRST\n");
> -		goto error_disable_reg;
> +		if (ret) {
> +			dev_err(&spi->dev, "failed to request GPIO PDRST\n");
> +			goto error_disable_reg;
> +		}
> +		st->powerdown_gpio = pdata->gpio_pdrst;
> +	} else {
> +		st->powerdown_gpio = -1;
>  	}
>  
>  	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
> @@ -212,7 +212,8 @@ static int __devinit ad7780_probe(struct spi_device *spi)
>  error_cleanup_buffer_and_trigger:
>  	ad_sd_cleanup_buffer_and_trigger(indio_dev);
>  error_free_gpio:
> -	gpio_free(pdata->gpio_pdrst);
> +	if (pdata && gpio_is_valid(pdata->gpio_pdrst))
> +		gpio_free(pdata->gpio_pdrst);
>  error_disable_reg:
>  	if (!IS_ERR(st->reg))
>  		regulator_disable(st->reg);
> @@ -233,7 +234,9 @@ static int __devexit ad7780_remove(struct spi_device *spi)
>  	iio_device_unregister(indio_dev);
>  	ad_sd_cleanup_buffer_and_trigger(indio_dev);
>  
> -	gpio_free(st->powerdown_gpio);
> +	if (gpio_is_valid(st->powerdown_gpio))
> +		gpio_free(st->powerdown_gpio);
> +
>  	if (!IS_ERR(st->reg)) {
>  		regulator_disable(st->reg);
>  		regulator_put(st->reg);
> 

Re: [PATCH 2/2] staging:iio:ad7780: Add support for the ad7170/ad7171

[Jonathan Cameron]

On 09/21/2012 02:29 PM, Lars-Peter Clausen wrote:
> The ad7170/ad7171 have a software interface similar to the ad7780. They do not
> have an external pin which allows to change the internal gain and the what is
> used for the gain bit in the ad7780/ad7781 becomes part of the check pattern.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
added to togreg branch of iio.git

Thanks,
> ---
>  drivers/staging/iio/adc/Kconfig  |    4 ++--
>  drivers/staging/iio/adc/ad7780.c |   36 ++++++++++++++++++++++++++++++------
>  2 files changed, 32 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
> index 1b4a356..a525143 100644
> --- a/drivers/staging/iio/adc/Kconfig
> +++ b/drivers/staging/iio/adc/Kconfig
> @@ -82,12 +82,12 @@ config AD7887
>  	  module will be called ad7887.
>  
>  config AD7780
> -	tristate "Analog Devices AD7780 AD7781 ADC driver"
> +	tristate "Analog Devices AD7780 and similar ADCs driver"
>  	depends on SPI
>  	depends on GPIOLIB
>  	select AD_SIGMA_DELTA
>  	help
> -	  Say yes here to build support for Analog Devices
> +	  Say yes here to build support for Analog Devices AD7170, AD7171,
>  	  AD7780 and AD7781 SPI analog to digital converters (ADC).
>  	  If unsure, say N (but it's safe to say "Y").
>  
> diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
> index 1dd7cdb..0a1328b 100644
> --- a/drivers/staging/iio/adc/ad7780.c
> +++ b/drivers/staging/iio/adc/ad7780.c
> @@ -1,5 +1,5 @@
>  /*
> - * AD7780/AD7781 SPI ADC driver
> + * AD7170/AD7171 and AD7780/AD7781 SPI ADC driver
>   *
>   * Copyright 2011 Analog Devices Inc.
>   *
> @@ -34,7 +34,9 @@
>  #define AD7780_PAT0	(1 << 0)
>  
>  struct ad7780_chip_info {
> -	struct iio_chan_spec		channel;
> +	struct iio_chan_spec	channel;
> +	unsigned int		pattern_mask;
> +	unsigned int		pattern;
>  };
>  
>  struct ad7780_state {
> @@ -48,6 +50,8 @@ struct ad7780_state {
>  };
>  
>  enum ad7780_supported_device_ids {
> +	ID_AD7170,
> +	ID_AD7171,
>  	ID_AD7780,
>  	ID_AD7781,
>  };
> @@ -109,9 +113,10 @@ static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
>  	unsigned int raw_sample)
>  {
>  	struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta);
> +	const struct ad7780_chip_info *chip_info = st->chip_info;
>  
>  	if ((raw_sample & AD7780_ERR) ||
> -		!((raw_sample & AD7780_PAT0) && !(raw_sample & AD7780_PAT1)))
> +		((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
>  		return -EIO;
>  
>  	if (raw_sample & AD7780_GAIN)
> @@ -128,12 +133,29 @@ static const struct ad_sigma_delta_info ad7780_sigma_delta_info = {
>  	.has_registers = false,
>  };
>  
> +#define AD7780_CHANNEL(bits, wordsize) \
> +	AD_SD_CHANNEL(1, 0, 0, bits, 32, wordsize - bits)
> +
>  static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
> +	[ID_AD7170] = {
> +		.channel = AD7780_CHANNEL(12, 24),
> +		.pattern = 0x5,
> +		.pattern_mask = 0x7,
> +	},
> +	[ID_AD7171] = {
> +		.channel = AD7780_CHANNEL(16, 24),
> +		.pattern = 0x5,
> +		.pattern_mask = 0x7,
> +	},
>  	[ID_AD7780] = {
> -		.channel = AD_SD_CHANNEL(1, 0, 0, 24, 32, 8),
> +		.channel = AD7780_CHANNEL(24, 32),
> +		.pattern = 0x1,
> +		.pattern_mask = 0x3,
>  	},
>  	[ID_AD7781] = {
> -		.channel = AD_SD_CHANNEL(1, 0, 0, 20, 32, 12),
> +		.channel = AD7780_CHANNEL(20, 32),
> +		.pattern = 0x1,
> +		.pattern_mask = 0x3,
>  	},
>  };
>  
> @@ -247,6 +269,8 @@ static int __devexit ad7780_remove(struct spi_device *spi)
>  }
>  
>  static const struct spi_device_id ad7780_id[] = {
> +	{"ad7170", ID_AD7170},
> +	{"ad7171", ID_AD7171},
>  	{"ad7780", ID_AD7780},
>  	{"ad7781", ID_AD7781},
>  	{}
> @@ -265,5 +289,5 @@ static struct spi_driver ad7780_driver = {
>  module_spi_driver(ad7780_driver);
>  
>  MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
> -MODULE_DESCRIPTION("Analog Devices AD7780/1 ADC");
> +MODULE_DESCRIPTION("Analog Devices AD7780 and similar ADCs");
>  MODULE_LICENSE("GPL v2");
>