[U-Boot] [PATCH V3 07/14] dm: adc: add simple ADC uclass implementation

[Przemyslaw Marczak <p.marczak@samsung.com>]

Hello all,

On 10/27/2015 01:08 PM, Przemyslaw Marczak wrote:
> This commit adds:
> - new uclass id: UCLASS_ADC
> - new uclass driver: drivers/adc/adc-uclass.c
>
> The new uclass's API allows for ADC operation on:
> * single-channel with channel selection by a number
> * multti-channel with channel selection by bit mask
>
> ADC uclass's functions:
> * single-channel:
>    - adc_start_channel()        - start channel conversion
>    - adc_channel_data()         - get conversion data
>    - adc_channel_single_shot()  - start/get conversion data
> * multi-channel:
>    - adc_start_channels()       - start selected channels conversion
>    - adc_channels_data()        - get conversion data
>    - adc_channels_single_shot() - start/get conversion data for channels
>                                   selected by bit mask
> * general:
>    - adc_stop()      - stop the conversion
>    - adc_vdd_value() - positive reference Voltage value with polarity [uV]
>    - adc_vss_value() - negative reference Voltage value with polarity [uV]
>    - adc_data_mask() - conversion data bit mask
>
> The device tree can provide below constraints/properties:
> - vdd-polarity-negative: if true: Vdd = vdd-microvolts * (-1)
> - vss-polarity-negative: if true: Vss = vss-microvolts * (-1)
> - vdd-supply:            phandle to Vdd regulator's node
> - vss-supply:            phandle to Vss regulator's node
> And optional, checked only if the above corresponding, doesn't exist:
>    - vdd-microvolts:      positive reference Voltage [uV]
>    - vss-microvolts:      negative reference Voltage [uV]
>
> Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
> Cc: Simon Glass <sjg@chromium.org>
> ---
> Changes V2:
> - new commit - introduce ADC uclass driver
> Changes V3:
> - Add binding info
> - ADC uclass's code rework, add single/multi-channel API
> - Select single channel by a number and multi, by a bit mask
> - Wait for conversion end in uclass's internal function
> - Add ADC supply polarity constraint
> - Add function for getting supply Voltage with polarity
> ---
>   doc/device-tree-bindings/adc/adc.txt |  62 ++++++
>   drivers/Kconfig                      |   2 +
>   drivers/Makefile                     |   1 +
>   drivers/adc/Kconfig                  |  12 +
>   drivers/adc/Makefile                 |   8 +
>   drivers/adc/adc-uclass.c             | 409 +++++++++++++++++++++++++++++++++++
>   include/adc.h                        | 288 ++++++++++++++++++++++++
>   include/dm/uclass-id.h               |   1 +
>   8 files changed, 783 insertions(+)
>   create mode 100644 doc/device-tree-bindings/adc/adc.txt
>   create mode 100644 drivers/adc/Kconfig
>   create mode 100644 drivers/adc/Makefile
>   create mode 100644 drivers/adc/adc-uclass.c
>   create mode 100644 include/adc.h
>

--- cut ---

> diff --git a/drivers/adc/adc-uclass.c b/drivers/adc/adc-uclass.c
> new file mode 100644
> index 0000000..9233fcd
> --- /dev/null
> +++ b/drivers/adc/adc-uclass.c
> @@ -0,0 +1,409 @@
> +/*
> + * Copyright (C) 2015 Samsung Electronics
> + * Przemyslaw Marczak <p.marczak@samsung.com>
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <errno.h>
> +#include <dm.h>
> +#include <dm/lists.h>
> +#include <dm/device-internal.h>
> +#include <dm/uclass-internal.h>
> +#include <adc.h>
> +#include <power/regulator.h>
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +#define ADC_UCLASS_PLATDATA_SIZE	sizeof(struct adc_uclass_platdata)
> +#define CHECK_NUMBER			true
> +#define CHECK_MASK			(!CHECK_NUMBER)
> +
> +/* TODO: add support for timer uclass (for early calls) */
> +#ifdef CONFIG_SANDBOX_ARCH
> +#define sdelay(x)	udelay(x)
> +#else
> +extern void sdelay(unsigned long loops);
> +#endif
--- cut ---

I would like precise the sdelay() calls in this code.

I didn't make the cleanup for the sdelay(), as Simon requested.

For some architectures it's declared in a different headers, but we have 
timer uclass now, so this sdelay mess can be used temporary.

Now, I don't have time for moving Exynos timer to driver model.
And also it should be done as a separated patch set.

Best regards,
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com