s3c_adc_battery: Average over more than one adc sample

Some sources for adc battery information provide only inaccurate results
where the read value differs from the real value with positive and negative
offsets. For such sources it can be more accurate to collect two or more
value sample and use the average of all collected values.

This patch adds pdata options volt_samples, current_samples and
backup_volt_samples to specifiy the number of samples to collect,
reads the specified number of samples and calculates the average of those.
For unset sample-number-values a default of 1 is assumed.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/s3c_adc_battery.h b/include/linux/s3c_adc_battery.h
index fbe58b7e63e..99dadbffdd4 100644
--- a/include/linux/s3c_adc_battery.h
+++ b/include/linux/s3c_adc_battery.h
@@ -25,6 +25,10 @@ struct s3c_adc_bat_pdata {
 	const unsigned int current_channel;
 	const unsigned int backup_volt_channel;
 
+	const unsigned int volt_samples;
+	const unsigned int current_samples;
+	const unsigned int backup_volt_samples;
+
 	const unsigned int volt_mult;
 	const unsigned int current_mult;
 	const unsigned int backup_volt_mult;