Re: [PATCH v3 4/4] iio: adc: at91_adc: remove platform data and move defs in driver file

[Alexandre Belloni]

On 30/09/2020 15:52:16+0300, Alexandru Ardelean wrote:
> The AT91 ADC driver no longer uses the 'at91_add_device_adc' platform data
> type. This is no longer used (at least in mainline drivers).

s/drivers/boards/

> 
> This change removes the platform-data initialization from the driver, since
> it is mostly dead code now.

It is definitively dead code, it has been a while that board file
support has been removed for the platforms with this ADC.

> 
> Some definitions [from the platform data at91_adc.h include] have been to
> be moved in the driver, since they are needed in the driver.

s/to be//

> 
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> ---
>  drivers/iio/adc/at91_adc.c             | 51 ++++++++++----------------
>  include/linux/platform_data/at91_adc.h | 49 -------------------------
>  2 files changed, 20 insertions(+), 80 deletions(-)
>  delete mode 100644 include/linux/platform_data/at91_adc.h
> 
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index 473bffe84fbd..d0e56b1b5949 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -22,8 +22,6 @@
>  #include <linux/slab.h>
>  #include <linux/wait.h>
>  
> -#include <linux/platform_data/at91_adc.h>
> -
>  #include <linux/iio/iio.h>
>  #include <linux/iio/buffer.h>
>  #include <linux/iio/trigger.h>
> @@ -153,6 +151,25 @@
>  #define TOUCH_SHTIM                    0xa
>  #define TOUCH_SCTIM_US		10		/* 10us for the Touchscreen Switches Closure Time */
>  
> +enum atmel_adc_ts_type {
> +	ATMEL_ADC_TOUCHSCREEN_NONE = 0,
> +	ATMEL_ADC_TOUCHSCREEN_4WIRE = 4,
> +	ATMEL_ADC_TOUCHSCREEN_5WIRE = 5,
> +};
> +
> +/**
> + * struct at91_adc_trigger - description of triggers
> + * @name:		name of the trigger advertised to the user
> + * @value:		value to set in the ADC's trigger setup register
> +			to enable the trigger
> + * @is_external:	Does the trigger rely on an external pin?
> + */
> +struct at91_adc_trigger {
> +	const char	*name;
> +	u8		value;
> +	bool		is_external;
> +};
> +
>  /**
>   * struct at91_adc_reg_desc - Various informations relative to registers
>   * @channel_base:	Base offset for the channel data registers
> @@ -957,30 +974,6 @@ static int at91_adc_probe_dt(struct iio_dev *idev,
>  	return ret;
>  }
>  
> -static int at91_adc_probe_pdata(struct at91_adc_state *st,
> -				struct platform_device *pdev)
> -{
> -	struct at91_adc_data *pdata = pdev->dev.platform_data;
> -
> -	if (!pdata)
> -		return -EINVAL;
> -
> -	st->caps = (struct at91_adc_caps *)
> -			platform_get_device_id(pdev)->driver_data;
> -
> -	st->use_external = pdata->use_external_triggers;
> -	st->vref_mv = pdata->vref;
> -	st->channels_mask = pdata->channels_used;
> -	st->num_channels = st->caps->num_channels;
> -	st->startup_time = pdata->startup_time;
> -	st->trigger_number = pdata->trigger_number;
> -	st->trigger_list = pdata->trigger_list;
> -	st->registers = &st->caps->registers;
> -	st->touchscreen_type = pdata->touchscreen_type;
> -
> -	return 0;
> -}
> -
>  static const struct iio_info at91_adc_info = {
>  	.read_raw = &at91_adc_read_raw,
>  };
> @@ -1157,11 +1150,7 @@ static int at91_adc_probe(struct platform_device *pdev)
>  
>  	st = iio_priv(idev);
>  
> -	if (pdev->dev.of_node)
> -		ret = at91_adc_probe_dt(idev, pdev);
> -	else
> -		ret = at91_adc_probe_pdata(st, pdev);
> -
> +	ret = at91_adc_probe_dt(idev, pdev);
>  	if (ret) {
>  		dev_err(&pdev->dev, "No platform data available.\n");
>  		return -EINVAL;

You can simply do:

	if (ret)
		return ret;

The debug message is not relevant anymore.

You can also remove:

	if (!node)
		return -EINVAL;

from at91_adc_probe_dt, there is no way the driver will probe without a
DT node.


> diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
> deleted file mode 100644
> index f20eaeb827ce..000000000000
> --- a/include/linux/platform_data/at91_adc.h
> +++ /dev/null
> @@ -1,49 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0-or-later */
> -/*
> - * Copyright (C) 2011 Free Electrons
> - */
> -
> -#ifndef _AT91_ADC_H_
> -#define _AT91_ADC_H_
> -
> -enum atmel_adc_ts_type {
> -	ATMEL_ADC_TOUCHSCREEN_NONE = 0,
> -	ATMEL_ADC_TOUCHSCREEN_4WIRE = 4,
> -	ATMEL_ADC_TOUCHSCREEN_5WIRE = 5,
> -};
> -
> -/**
> - * struct at91_adc_trigger - description of triggers
> - * @name:		name of the trigger advertised to the user
> - * @value:		value to set in the ADC's trigger setup register
> -			to enable the trigger
> - * @is_external:	Does the trigger rely on an external pin?
> - */
> -struct at91_adc_trigger {
> -	const char	*name;
> -	u8		value;
> -	bool		is_external;
> -};
> -
> -/**
> - * struct at91_adc_data - platform data for ADC driver
> - * @channels_used:		channels in use on the board as a bitmask
> - * @startup_time:		startup time of the ADC in microseconds
> - * @trigger_list:		Triggers available in the ADC
> - * @trigger_number:		Number of triggers available in the ADC
> - * @use_external_triggers:	does the board has external triggers availables
> - * @vref:			Reference voltage for the ADC in millivolts
> - * @touchscreen_type:		If a touchscreen is connected, its type (4 or 5 wires)
> - */
> -struct at91_adc_data {
> -	unsigned long			channels_used;
> -	u8				startup_time;
> -	struct at91_adc_trigger		*trigger_list;
> -	u8				trigger_number;
> -	bool				use_external_triggers;
> -	u16				vref;
> -	enum atmel_adc_ts_type		touchscreen_type;
> -};
> -
> -extern void __init at91_add_device_adc(struct at91_adc_data *data);
> -#endif
> -- 
> 2.17.1
> 

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com