Re: [PATCH] iio: adc: at91_adc: allow to use full range of startup time

[Alexandre Belloni <alexandre.belloni@free-electrons.com>]

On 17/06/2015 at 18:21:36 +0200, Nicolas Ferre wrote :
> From: Jan Leupold <leupold@rsi-elektrotechnik.de>
> 
> The DT-Property "atmel,adc-startup-time" is stored in an u8 for a microsecond
> value. When trying to increase the value of STARTUP in Register AT91_ADC_MR
> some higher values can't be reached.
> 
> Change the type in function parameter and private structure field from u8 to
> u32.
> 
> Signed-off-by: Jan Leupold <leupold@rsi-elektrotechnik.de>
> [nicolas.ferre@atmel.com: change commit message, increase u16 to u32 for startup time]
> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

> ---
>  drivers/iio/adc/at91_adc.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index 8a0eb4a04fb5..7b40925dd4ff 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -182,7 +182,7 @@ struct at91_adc_caps {
>  	u8	ts_pen_detect_sensitivity;
>  
>  	/* startup time calculate function */
> -	u32 (*calc_startup_ticks)(u8 startup_time, u32 adc_clk_khz);
> +	u32 (*calc_startup_ticks)(u32 startup_time, u32 adc_clk_khz);
>  
>  	u8	num_channels;
>  	struct at91_adc_reg_desc registers;
> @@ -201,7 +201,7 @@ struct at91_adc_state {
>  	u8			num_channels;
>  	void __iomem		*reg_base;
>  	struct at91_adc_reg_desc *registers;
> -	u8			startup_time;
> +	u32			startup_time;
>  	u8			sample_hold_time;
>  	bool			sleep_mode;
>  	struct iio_trigger	**trig;
> @@ -779,7 +779,7 @@ ret:
>  	return ret;
>  }
>  
> -static u32 calc_startup_ticks_9260(u8 startup_time, u32 adc_clk_khz)
> +static u32 calc_startup_ticks_9260(u32 startup_time, u32 adc_clk_khz)
>  {
>  	/*
>  	 * Number of ticks needed to cover the startup time of the ADC
> @@ -790,7 +790,7 @@ static u32 calc_startup_ticks_9260(u8 startup_time, u32 adc_clk_khz)
>  	return round_up((startup_time * adc_clk_khz / 1000) - 1, 8) / 8;
>  }
>  
> -static u32 calc_startup_ticks_9x5(u8 startup_time, u32 adc_clk_khz)
> +static u32 calc_startup_ticks_9x5(u32 startup_time, u32 adc_clk_khz)
>  {
>  	/*
>  	 * For sama5d3x and at91sam9x5, the formula changes to:
> -- 
> 2.1.3
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com