Re: [PATCH 3/3] ARM: AT91: Add the ADC to the sam9g20ek board

[Nicolas Ferre <nicolas.ferre@atmel.com>]

On 11/14/2011 04:17 PM, Maxime Ripard :
> Hi Nicolas,
> 
> On 14/11/2011 12:29, Nicolas Ferre wrote:
>> On 11/14/2011 11:06 AM, Maxime Ripard :
>>> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
>>> Cc: Patrice Vilchez <patrice.vilchez@atmel.com>
>>> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
>>>
>>> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
>>
>>
>> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
>>
>> (even if I have a tiny comment: see below)
>>
>>> ---
>>>  arch/arm/mach-at91/at91sam9260_devices.c |   52 ++++++++++++++++++++++++++++++
>>>  arch/arm/mach-at91/board-sam9g20ek.c     |   11 ++++++
>>>  2 files changed, 63 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c
>>> index 39f81f4..0859553 100644
>>> --- a/arch/arm/mach-at91/at91sam9260_devices.c
>>> +++ b/arch/arm/mach-at91/at91sam9260_devices.c
>>> @@ -1312,6 +1312,58 @@ void __init at91_add_device_cf(struct at91_cf_data *data)
>>>  void __init at91_add_device_cf(struct at91_cf_data * data) {}
>>>  #endif
>>>  
>>> +/* --------------------------------------------------------------------
>>> + *  ADCs
>>> + * -------------------------------------------------------------------- */
>>
>> What about adding all this only if the IIO_AT91ADC is selected?
>> Otherwise, you configure pins without actually using them...
> 
> I'm not sure on what I should do here. Should I only wrap the pin
> configuration part in the at91_add_device_adc function in an ifdef, or
> wrap all there is in this patch (that is structure definitions,
> at91_add_device_adc declaration and call, etc) by the ifdef ?

I mean all adc material surrounded by ifdefs with empty function call if
not selected. I was only talking about the pin configuration because the
additional structure size is not so much a big deal.

>>> +
>>> +static struct at91_adc_data adc_data;
>>> +
>>> +static struct resource adc_resources[] = {
>>> +	[0] = {
>>> +		.start	= AT91SAM9260_BASE_ADC,
>>> +		.end	= AT91SAM9260_BASE_ADC + SZ_16K - 1,
>>> +		.flags	= IORESOURCE_MEM,
>>> +	},
>>> +	[1] = {
>>> +		.start	= AT91SAM9260_ID_ADC,
>>> +		.end	= AT91SAM9260_ID_ADC,
>>> +		.flags	= IORESOURCE_IRQ,
>>> +	},
>>> +};
>>> +
>>> +static struct platform_device at91_adc_device = {
>>> +	.name		= "at91adc",
>>> +	.id		= -1,
>>> +	.dev		= {
>>> +				.platform_data		= &adc_data,
>>> +	},
>>> +	.resource	= adc_resources,
>>> +	.num_resources	= ARRAY_SIZE(adc_resources),
>>> +};
>>> +
>>> +void __init at91_add_device_adc(struct at91_adc_data *data)
>>> +{
>>> +	if (!data)
>>> +		return;
>>> +
>>> +	if (test_bit(0, &(data->channels_used)))
>>> +		at91_set_A_periph(AT91_PIN_PC0, 0);
>>> +	if (test_bit(1, &(data->channels_used)))
>>> +		at91_set_A_periph(AT91_PIN_PC1, 0);
>>> +	if (test_bit(2, &(data->channels_used)))
>>> +		at91_set_A_periph(AT91_PIN_PC2, 0);
>>> +	if (test_bit(3, &(data->channels_used)))
>>> +		at91_set_A_periph(AT91_PIN_PC3, 0);
>>> +
>>> +	data->adc_clock = 5000000;
>>> +	data->num_channels = 4;
>>> +	data->startup_time = 10;
>>> +
>>> +	adc_data = *data;
>>> +	platform_device_register(&at91_adc_device);
>>> +}
>>> +
>>> +
>>>  /* -------------------------------------------------------------------- */
>>>  /*
>>>   * These devices are always present and don't need any board-specific
>>> diff --git a/arch/arm/mach-at91/board-sam9g20ek.c b/arch/arm/mach-at91/board-sam9g20ek.c
>>> index 817f59d..e34d41a 100644
>>> --- a/arch/arm/mach-at91/board-sam9g20ek.c
>>> +++ b/arch/arm/mach-at91/board-sam9g20ek.c
>>> @@ -314,6 +314,15 @@ static void __init ek_add_device_buttons(void)
>>>  static void __init ek_add_device_buttons(void) {}
>>>  #endif
>>>  
>>> +/*
>>> + * ADCs
>>> + */
>>> +
>>> +static struct at91_adc_data ek_adc_data = {
>>> +	.channels_used = BIT(0) | BIT(1) | BIT(2) | BIT(3),
>>> +	.vref = 3300,
>>> +};
>>> +
>>>  #if defined(CONFIG_REGULATOR_FIXED_VOLTAGE) || defined(CONFIG_REGULATOR_FIXED_VOLTAGE_MODULE)
>>>  static struct regulator_consumer_supply ek_audio_consumer_supplies[] = {
>>>  	REGULATOR_SUPPLY("AVDD", "0-001b"),
>>> @@ -389,6 +398,8 @@ static void __init ek_board_init(void)
>>>  	ek_add_device_gpio_leds();
>>>  	/* Push Buttons */
>>>  	ek_add_device_buttons();
>>> +	/* ADCs */
>>> +	at91_add_device_adc(&ek_adc_data);
>>>  	/* PCK0 provides MCLK to the WM8731 */
>>>  	at91_set_B_periph(AT91_PIN_PC1, 0);
>>>  	/* SSC (for WM8731) */


Bye,
-- 
Nicolas Ferre