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authorGuenter Roeck <linux@roeck-us.net>2016-09-09 04:10:00 +0200
committerSebastian Reichel <sre@kernel.org>2016-09-19 21:02:17 +0200
commit17c6d3979e5bbff1de36a4e89015fa09ac495d27 (patch)
treeef0dd71aebc4183c4c7c00baadc7fa1ef8cc9e7d /drivers/power
parentpower: bq24257: Fix use of uninitialized pointer bq->charger (diff)
downloadlinux-17c6d3979e5bbff1de36a4e89015fa09ac495d27.tar.xz
linux-17c6d3979e5bbff1de36a4e89015fa09ac495d27.zip
sbs-battery: make writes to ManufacturerAccess optional
According to the Smart Battery Data Specification, the use of ManufacturerAcess (register 0x0) is implementation-defined. It appears that some batteries use writes to this register in order to implement certain functionality, but others may simply NAK all writes to it. As a result, write failures to ManufacturerAccess should not be used as an indicator of battery presence, nor as a failure to enter sleep mode. The failed write access was seen with SANYO AP13J3K. Cc: Brian Norris <briannorris@chromium.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Sebastian Reichel <sre@kernel.org>
Diffstat (limited to 'drivers/power')
-rw-r--r--drivers/power/supply/sbs-battery.c29
1 files changed, 15 insertions, 14 deletions
diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
index 248a5dd75e22..bc7acdf84d60 100644
--- a/drivers/power/supply/sbs-battery.c
+++ b/drivers/power/supply/sbs-battery.c
@@ -317,21 +317,22 @@ static int sbs_get_battery_presence_and_health(
return ret;
}
- /* Write to ManufacturerAccess with
- * ManufacturerAccess command and then
- * read the status */
- ret = sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
- MANUFACTURER_ACCESS_STATUS);
+ /*
+ * Write to ManufacturerAccess with ManufacturerAccess command
+ * and then read the status. Do not check for error on the write
+ * since not all batteries implement write access to this command,
+ * while others mandate it.
+ */
+ sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
+ MANUFACTURER_ACCESS_STATUS);
+
+ ret = sbs_read_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr);
if (ret < 0) {
if (psp == POWER_SUPPLY_PROP_PRESENT)
val->intval = 0; /* battery removed */
return ret;
}
- ret = sbs_read_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr);
- if (ret < 0)
- return ret;
-
if (ret < sbs_data[REG_MANUFACTURER_DATA].min_value ||
ret > sbs_data[REG_MANUFACTURER_DATA].max_value) {
val->intval = 0;
@@ -882,16 +883,16 @@ static int sbs_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct sbs_info *chip = i2c_get_clientdata(client);
- s32 ret;
if (chip->poll_time > 0)
cancel_delayed_work_sync(&chip->work);
- /* write to manufacturer access with sleep command */
- ret = sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
+ /*
+ * Write to manufacturer access with sleep command.
+ * Support is manufacturer dependend, so ignore errors.
+ */
+ sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
MANUFACTURER_ACCESS_SLEEP);
- if (chip->is_present && ret < 0)
- return ret;
return 0;
}