[PATCH 3.16.y-ckt 021/118] iio: adc: at91_adc: allow to use full range of startup time

From: Luis Henriques
Date: Wed Aug 12 2015 - 05:38:08 EST


3.16.7-ckt16 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Jan Leupold <leupold@xxxxxxxxxxxxxxxxxxxxx>

commit 2ab5f39bc7825808e0fa1e7e5f0b23e174563467 upstream.

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@xxxxxxxxxxxxxxxxxxxxx>
[nicolas.ferre@xxxxxxxxx: change commit message, increase u16 to u32 for startup time]
Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Acked-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
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 e7ff26a4aef9..fa5d299d9222 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:
--
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