diff mbox

power:bq27xxx: 27000/10 read FLAGS register as single

Message ID 6ff28e18f78d1b9581cba5fd214fcc00e4a6d23a.1468858328.git.hns@goldelico.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

H. Nikolaus Schaller July 18, 2016, 4:12 p.m. UTC
The bq27000 and bq27010 have a single byte FLAGS register.
Other gauges have 16 bit FLAGS registers.

For reading the FLAGS register it is sufficient to read the single
register instead of reading RSOC at the next higher address as
well and then ignore the high byte.

This does not change functionality but optimizes i2c and hdq
traffic.

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
---
 drivers/power/bq27xxx_battery.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

H. Nikolaus Schaller July 26, 2016, 6:08 a.m. UTC | #1
ping

> Am 18.07.2016 um 18:12 schrieb H. Nikolaus Schaller <hns@goldelico.com>:
> 
> The bq27000 and bq27010 have a single byte FLAGS register.
> Other gauges have 16 bit FLAGS registers.
> 
> For reading the FLAGS register it is sufficient to read the single
> register instead of reading RSOC at the next higher address as
> well and then ignore the high byte.
> 
> This does not change functionality but optimizes i2c and hdq
> traffic.
> 
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
> ---
> drivers/power/bq27xxx_battery.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
> index 45f6ebf..56712b2 100644
> --- a/drivers/power/bq27xxx_battery.c
> +++ b/drivers/power/bq27xxx_battery.c
> @@ -656,8 +656,9 @@ static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
> static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
> {
> 	int flags;
> +	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
> 
> -	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
> +	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
> 	if (flags < 0) {
> 		dev_err(di->dev, "error reading flag register:%d\n", flags);
> 		return flags;
> @@ -760,7 +761,7 @@ static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
> 	}
> 
> 	if (di->chip == BQ27000 || di->chip == BQ27010) {
> -		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
> +		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
> 		if (flags & BQ27000_FLAG_CHGS) {
> 			dev_dbg(di->dev, "negative current!\n");
> 			curr = -curr;
> -- 
> 2.7.3
> 

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Pali Rohár July 26, 2016, 7:27 a.m. UTC | #2
On Monday 18 July 2016 18:12:09 H. Nikolaus Schaller wrote:
> The bq27000 and bq27010 have a single byte FLAGS register.
> Other gauges have 16 bit FLAGS registers.
> 
> For reading the FLAGS register it is sufficient to read the single
> register instead of reading RSOC at the next higher address as
> well and then ignore the high byte.
> 
> This does not change functionality but optimizes i2c and hdq
> traffic.
> 
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>

Looks good, add my Acked-by.
Andrew Davis July 26, 2016, 1:04 p.m. UTC | #3
On 07/18/2016 11:12 AM, H. Nikolaus Schaller wrote:
> The bq27000 and bq27010 have a single byte FLAGS register.
> Other gauges have 16 bit FLAGS registers.
> 
> For reading the FLAGS register it is sufficient to read the single
> register instead of reading RSOC at the next higher address as
> well and then ignore the high byte.
> 
> This does not change functionality but optimizes i2c and hdq
> traffic.
> 
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
> ---

Matches the datasheet,

Acked-by: Andrew F. Davis <afd@ti.com>

>  drivers/power/bq27xxx_battery.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
> index 45f6ebf..56712b2 100644
> --- a/drivers/power/bq27xxx_battery.c
> +++ b/drivers/power/bq27xxx_battery.c
> @@ -656,8 +656,9 @@ static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
>  static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
>  {
>  	int flags;
> +	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
>  
> -	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
> +	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
>  	if (flags < 0) {
>  		dev_err(di->dev, "error reading flag register:%d\n", flags);
>  		return flags;
> @@ -760,7 +761,7 @@ static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
>  	}
>  
>  	if (di->chip == BQ27000 || di->chip == BQ27010) {
> -		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
> +		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
>  		if (flags & BQ27000_FLAG_CHGS) {
>  			dev_dbg(di->dev, "negative current!\n");
>  			curr = -curr;
> 
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Sebastian Reichel Aug. 15, 2016, 7:27 p.m. UTC | #4
Hi,

On Mon, Jul 18, 2016 at 06:12:09PM +0200, H. Nikolaus Schaller wrote:
> The bq27000 and bq27010 have a single byte FLAGS register.
> Other gauges have 16 bit FLAGS registers.
> 
> For reading the FLAGS register it is sufficient to read the single
> register instead of reading RSOC at the next higher address as
> well and then ignore the high byte.
> 
> This does not change functionality but optimizes i2c and hdq
> traffic.

Thanks, queued into power-supply's -next branch.

-- Sebastian
diff mbox

Patch

diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
index 45f6ebf..56712b2 100644
--- a/drivers/power/bq27xxx_battery.c
+++ b/drivers/power/bq27xxx_battery.c
@@ -656,8 +656,9 @@  static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
 static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
 {
 	int flags;
+	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
 
-	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
+	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
 	if (flags < 0) {
 		dev_err(di->dev, "error reading flag register:%d\n", flags);
 		return flags;
@@ -760,7 +761,7 @@  static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
 	}
 
 	if (di->chip == BQ27000 || di->chip == BQ27010) {
-		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
+		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
 		if (flags & BQ27000_FLAG_CHGS) {
 			dev_dbg(di->dev, "negative current!\n");
 			curr = -curr;