[PATCH v2] power: supply: bq27xxx: Divide the reg cache to each register
From: Hermes Zhang
Date: Wed Mar 06 2024 - 05:09:57 EST
The reg cache used to be grouped and activated for each property
access, regardless of whether it was part of the group. That will
lead to a significant increase in I2C transmission.
Divide the cache group and create a cache for every register. The
cache won't work until the register has been fetched. This will help
in reducing the quantity of pointless I2C communication and avoiding
the error -16 (EBUSY) that occurs while using an I2C bus that is
shared by many devices.
Signed-off-by: Hermes Zhang <Hermes.Zhang@xxxxxxxx>
---
v2:
- Refactor implementation.
drivers/power/supply/bq27xxx_battery.c | 231 +++++++++++++++++--------
include/linux/power/bq27xxx_battery.h | 30 ++--
2 files changed, 179 insertions(+), 82 deletions(-)
diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c
index 1c4a9d137744..cc724322f4f0 100644
--- a/drivers/power/supply/bq27xxx_battery.c
+++ b/drivers/power/supply/bq27xxx_battery.c
@@ -1746,14 +1746,16 @@ static bool bq27xxx_battery_capacity_inaccurate(struct bq27xxx_device_info *di,
static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
{
+ int flags = di->cache[CACHE_REG_FLAGS].value;
+
/* Unlikely but important to return first */
- if (unlikely(bq27xxx_battery_overtemp(di, di->cache.flags)))
+ if (unlikely(bq27xxx_battery_overtemp(di, flags)))
return POWER_SUPPLY_HEALTH_OVERHEAT;
- if (unlikely(bq27xxx_battery_undertemp(di, di->cache.flags)))
+ if (unlikely(bq27xxx_battery_undertemp(di, flags)))
return POWER_SUPPLY_HEALTH_COLD;
- if (unlikely(bq27xxx_battery_dead(di, di->cache.flags)))
+ if (unlikely(bq27xxx_battery_dead(di, flags)))
return POWER_SUPPLY_HEALTH_DEAD;
- if (unlikely(bq27xxx_battery_capacity_inaccurate(di, di->cache.flags)))
+ if (unlikely(bq27xxx_battery_capacity_inaccurate(di, flags)))
return POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED;
return POWER_SUPPLY_HEALTH_GOOD;
@@ -1778,7 +1780,7 @@ static int bq27xxx_battery_current_and_status(
struct bq27xxx_device_info *di,
union power_supply_propval *val_curr,
union power_supply_propval *val_status,
- struct bq27xxx_reg_cache *cache)
+ struct bq27xxx_cache_reg *reg)
{
bool single_flags = (di->opts & BQ27XXX_O_ZERO);
int curr;
@@ -1790,8 +1792,8 @@ static int bq27xxx_battery_current_and_status(
return curr;
}
- if (cache) {
- flags = cache->flags;
+ if (reg) {
+ flags = reg->value;
} else {
flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, single_flags);
if (flags < 0) {
@@ -1832,57 +1834,128 @@ static int bq27xxx_battery_current_and_status(
return 0;
}
-static void bq27xxx_battery_update_unlocked(struct bq27xxx_device_info *di)
+static int bq27xxx_cached_reg_value_unlocked(struct bq27xxx_device_info *di,
+ enum bq27xxx_cache_registers item)
{
- union power_supply_propval status = di->last_status;
- struct bq27xxx_reg_cache cache = {0, };
- bool has_singe_flag = di->opts & BQ27XXX_O_ZERO;
-
- cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
- if ((cache.flags & 0xff) == 0xff)
- cache.flags = -1; /* read error */
- if (cache.flags >= 0) {
- cache.temperature = bq27xxx_battery_read_temperature(di);
+ struct bq27xxx_cache_reg *reg;
+ int tmp = -EINVAL;
+
+ reg = &di->cache[item];
+
+ if (time_is_after_jiffies(reg->last_update + 5 * HZ))
+ return reg->value;
+
+ switch (item) {
+ case CACHE_REG_TEMPERATURE:
+ tmp = bq27xxx_battery_read_temperature(di);
+ break;
+ case CACHE_REG_TIME_TO_EMPTY:
if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
- cache.time_to_empty = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
+ tmp = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
+ break;
+ case CACHE_REG_TIME_TO_EMPTY_AVG:
if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
- cache.time_to_empty_avg = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
+ tmp = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
+ break;
+ case CACHE_REG_TIME_TO_FULL:
if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
- cache.time_to_full = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
-
- cache.charge_full = bq27xxx_battery_read_fcc(di);
- cache.capacity = bq27xxx_battery_read_soc(di);
- if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
- cache.energy = bq27xxx_battery_read_energy(di);
- di->cache.flags = cache.flags;
- cache.health = bq27xxx_battery_read_health(di);
+ tmp = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
+ break;
+ case CACHE_REG_CHARGE_FULL:
+ tmp = bq27xxx_battery_read_fcc(di);
+ break;
+ case CACHE_REG_CYCLE_COUNT:
if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
- cache.cycle_count = bq27xxx_battery_read_cyct(di);
-
- /*
- * On gauges with signed current reporting the current must be
- * checked to detect charging <-> discharging status changes.
- */
- if (!(di->opts & BQ27XXX_O_ZERO))
- bq27xxx_battery_current_and_status(di, NULL, &status, &cache);
-
- /* We only have to read charge design full once */
- if (di->charge_design_full <= 0)
- di->charge_design_full = bq27xxx_battery_read_dcap(di);
+ tmp = bq27xxx_battery_read_cyct(di);
+ break;
+ case CACHE_REG_CAPACITY:
+ tmp = bq27xxx_battery_read_soc(di);
+ break;
+ case CACHE_REG_ENERGY:
+ if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
+ tmp = bq27xxx_battery_read_energy(di);
+ break;
+ case CACHE_REG_FLAGS:
+ bool has_singe_flag = di->opts & BQ27XXX_O_ZERO;
+
+ tmp = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
+ if ((tmp & 0xff) == 0xff)
+ tmp = -1; /* read error */
+ break;
+ default:
+ break;
+ }
+
+ /* only update cache value when successful */
+ if (tmp >= 0) {
+ reg->value = tmp;
+ reg->last_update = jiffies;
}
- if ((di->cache.capacity != cache.capacity) ||
- (di->cache.flags != cache.flags) ||
+ return tmp;
+}
+
+static int bq27xxx_cached_reg_value(struct bq27xxx_device_info *di,
+ enum bq27xxx_cache_registers item)
+{
+ int ret;
+
+ mutex_lock(&di->lock);
+ ret = bq27xxx_cached_reg_value_unlocked(di, item);
+ mutex_unlock(&di->lock);
+
+ return ret;
+}
+
+static void bq27xxx_battery_update_unlocked(struct bq27xxx_device_info *di)
+{
+ union power_supply_propval status = di->last_status;
+ int old_flags, flags;
+ int old_capacity, capacity;
+
+ old_capacity = di->cache[CACHE_REG_CAPACITY].value;
+ capacity = old_capacity;
+
+ old_flags = di->cache[CACHE_REG_FLAGS].value;
+ flags = bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_FLAGS);
+
+ if (flags < 0)
+ goto out;
+
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_TEMPERATURE);
+ if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_TIME_TO_EMPTY);
+ if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_TIME_TO_EMPTY_AVG);
+ if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_TIME_TO_FULL);
+
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_CHARGE_FULL);
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_CAPACITY);
+ if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_ENERGY);
+ if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
+ bq27xxx_cached_reg_value_unlocked(di, CACHE_REG_CYCLE_COUNT);
+
+ /*
+ * On gauges with signed current reporting the current must be
+ * checked to detect charging <-> discharging status changes.
+ */
+ if (!(di->opts & BQ27XXX_O_ZERO))
+ bq27xxx_battery_current_and_status(di, NULL, &status,
+ &di->cache[CACHE_REG_FLAGS]);
+
+ /* We only have to read charge design full once */
+ if (di->charge_design_full <= 0)
+ di->charge_design_full = bq27xxx_battery_read_dcap(di);
+
+out:
+ if ((old_capacity != capacity) || (old_flags != flags) ||
(di->last_status.intval != status.intval)) {
di->last_status.intval = status.intval;
power_supply_changed(di->bat);
}
- if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
- di->cache = cache;
-
- di->last_update = jiffies;
-
if (!di->removed && poll_interval > 0)
mod_delayed_work(system_wq, &di->work, poll_interval * HZ);
}
@@ -1934,29 +2007,32 @@ static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
union power_supply_propval *val)
{
int level;
+ int flags;
+
+ flags = di->cache[CACHE_REG_FLAGS].value;
if (di->opts & BQ27XXX_O_ZERO) {
- if (di->cache.flags & BQ27000_FLAG_FC)
+ if (flags & BQ27000_FLAG_FC)
level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
- else if (di->cache.flags & BQ27000_FLAG_EDVF)
+ else if (flags & BQ27000_FLAG_EDVF)
level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
- else if (di->cache.flags & BQ27000_FLAG_EDV1)
+ else if (flags & BQ27000_FLAG_EDV1)
level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
else
level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
} else if (di->opts & BQ27Z561_O_BITS) {
- if (di->cache.flags & BQ27Z561_FLAG_FC)
+ if (flags & BQ27Z561_FLAG_FC)
level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
- else if (di->cache.flags & BQ27Z561_FLAG_FDC)
+ else if (flags & BQ27Z561_FLAG_FDC)
level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
else
level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
} else {
- if (di->cache.flags & BQ27XXX_FLAG_FC)
+ if (flags & BQ27XXX_FLAG_FC)
level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
- else if (di->cache.flags & BQ27XXX_FLAG_SOCF)
+ else if (flags & BQ27XXX_FLAG_SOCF)
level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
- else if (di->cache.flags & BQ27XXX_FLAG_SOC1)
+ else if (flags & BQ27XXX_FLAG_SOC1)
level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
else
level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
@@ -2004,13 +2080,12 @@ static int bq27xxx_battery_get_property(struct power_supply *psy,
{
int ret = 0;
struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
+ int flags;
+ int cache;
- mutex_lock(&di->lock);
- if (time_is_before_jiffies(di->last_update + 5 * HZ))
- bq27xxx_battery_update_unlocked(di);
- mutex_unlock(&di->lock);
+ flags = bq27xxx_cached_reg_value(di, CACHE_REG_FLAGS);
- if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
+ if (psp != POWER_SUPPLY_PROP_PRESENT && flags < 0)
return -ENODEV;
switch (psp) {
@@ -2021,30 +2096,40 @@ static int bq27xxx_battery_get_property(struct power_supply *psy,
ret = bq27xxx_battery_voltage(di, val);
break;
case POWER_SUPPLY_PROP_PRESENT:
- val->intval = di->cache.flags < 0 ? 0 : 1;
+ val->intval = flags < 0 ? 0 : 1;
break;
case POWER_SUPPLY_PROP_CURRENT_NOW:
ret = bq27xxx_battery_current_and_status(di, val, NULL, NULL);
break;
case POWER_SUPPLY_PROP_CAPACITY:
- ret = bq27xxx_simple_value(di->cache.capacity, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_CAPACITY);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
ret = bq27xxx_battery_capacity_level(di, val);
break;
case POWER_SUPPLY_PROP_TEMP:
- ret = bq27xxx_simple_value(di->cache.temperature, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_TEMPERATURE);
+
+ ret = bq27xxx_simple_value(cache, val);
if (ret == 0)
val->intval -= 2731; /* convert decidegree k to c */
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
- ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_TIME_TO_EMPTY);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
- ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_TIME_TO_EMPTY_AVG);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
- ret = bq27xxx_simple_value(di->cache.time_to_full, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_TIME_TO_FULL);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
if (di->opts & BQ27XXX_O_MUL_CHEM)
@@ -2059,7 +2144,9 @@ static int bq27xxx_battery_get_property(struct power_supply *psy,
ret = bq27xxx_simple_value(bq27xxx_battery_read_rc(di), val);
break;
case POWER_SUPPLY_PROP_CHARGE_FULL:
- ret = bq27xxx_simple_value(di->cache.charge_full, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_CHARGE_FULL);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
ret = bq27xxx_simple_value(di->charge_design_full, val);
@@ -2072,16 +2159,22 @@ static int bq27xxx_battery_get_property(struct power_supply *psy,
case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
return -EINVAL;
case POWER_SUPPLY_PROP_CYCLE_COUNT:
- ret = bq27xxx_simple_value(di->cache.cycle_count, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_CYCLE_COUNT);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_ENERGY_NOW:
- ret = bq27xxx_simple_value(di->cache.energy, val);
+ cache = bq27xxx_cached_reg_value(di, CACHE_REG_ENERGY);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_POWER_AVG:
ret = bq27xxx_battery_pwr_avg(di, val);
break;
case POWER_SUPPLY_PROP_HEALTH:
- ret = bq27xxx_simple_value(di->cache.health, val);
+ cache = bq27xxx_battery_read_health(di);
+
+ ret = bq27xxx_simple_value(cache, val);
break;
case POWER_SUPPLY_PROP_MANUFACTURER:
val->strval = BQ27XXX_MANUFACTURER;
diff --git a/include/linux/power/bq27xxx_battery.h b/include/linux/power/bq27xxx_battery.h
index 7d8025fb74b7..617c8409d80f 100644
--- a/include/linux/power/bq27xxx_battery.h
+++ b/include/linux/power/bq27xxx_battery.h
@@ -46,17 +46,22 @@ struct bq27xxx_access_methods {
int (*write_bulk)(struct bq27xxx_device_info *di, u8 reg, u8 *data, int len);
};
-struct bq27xxx_reg_cache {
- int temperature;
- int time_to_empty;
- int time_to_empty_avg;
- int time_to_full;
- int charge_full;
- int cycle_count;
- int capacity;
- int energy;
- int flags;
- int health;
+struct bq27xxx_cache_reg {
+ int value;
+ unsigned long last_update;
+};
+
+enum bq27xxx_cache_registers {
+ CACHE_REG_TEMPERATURE = 0,
+ CACHE_REG_TIME_TO_EMPTY,
+ CACHE_REG_TIME_TO_EMPTY_AVG,
+ CACHE_REG_TIME_TO_FULL,
+ CACHE_REG_CHARGE_FULL,
+ CACHE_REG_CYCLE_COUNT,
+ CACHE_REG_CAPACITY,
+ CACHE_REG_ENERGY,
+ CACHE_REG_FLAGS,
+ CACHE_REG_MAX,
};
struct bq27xxx_device_info {
@@ -68,10 +73,9 @@ struct bq27xxx_device_info {
struct bq27xxx_dm_reg *dm_regs;
u32 unseal_key;
struct bq27xxx_access_methods bus;
- struct bq27xxx_reg_cache cache;
+ struct bq27xxx_cache_reg cache[CACHE_REG_MAX];
int charge_design_full;
bool removed;
- unsigned long last_update;
union power_supply_propval last_status;
struct delayed_work work;
struct power_supply *bat;
--
2.39.2