2015-06-17 16:21:26

by Nicolas Ferre

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

From: Jan Leupold <[email protected]>

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 <[email protected]>
[[email protected]: change commit message, increase u16 to u32 for startup time]
Signed-off-by: Nicolas Ferre <[email protected]>
---
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

2015-06-18 14:02:41

by Alexandre Belloni

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

On 17/06/2015 at 18:21:36 +0200, Nicolas Ferre wrote :
> From: Jan Leupold <[email protected]>
>
> 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 <[email protected]>
> [[email protected]: change commit message, increase u16 to u32 for startup time]
> Signed-off-by: Nicolas Ferre <[email protected]>
Acked-by: Alexandre Belloni <[email protected]>

> ---
> 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

2015-06-21 13:07:19

by Jonathan Cameron

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

On 18/06/15 15:02, Alexandre Belloni wrote:
> On 17/06/2015 at 18:21:36 +0200, Nicolas Ferre wrote :
>> From: Jan Leupold <[email protected]>
>>
>> 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 <[email protected]>
>> [[email protected]: change commit message, increase u16 to u32 for startup time]
>> Signed-off-by: Nicolas Ferre <[email protected]>
> Acked-by: Alexandre Belloni <[email protected]>
Applied to the fixes-togreg branch of iio.git and marked for stable.
Probably won't now go upstream until post merge window.

Thanks,

Jonathan
>
>> ---
>> 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:Acked-by: Alexandre Belloni <[email protected]>
>> 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
>>
>