[PATCH 0/3] power: supply: cpcap-battery improvements

[PATCH 0/3] power: supply: cpcap-battery improvements

[Ivaylo Dimitrov]

This patch series implements few improvememts to cpcap-battery driver

[PATCH 1/3] power: cpcap-battery: Do not issue low signal too frequently

[Ivaylo Dimitrov]

It seems that low battery irq may be generated tens of times per second,
leading to userspace being flooded with unnecessary events.

Fix that by preventing such events being generated more than once every 30
seconds.

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
---
 drivers/power/supply/cpcap-battery.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
index 4676560..2659df7 100644
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -137,6 +137,7 @@ struct cpcap_battery_ddata {
 	struct power_supply *psy;
 	struct cpcap_battery_config config;
 	struct cpcap_battery_state_data state[CPCAP_BATTERY_STATE_NR];
+	struct timer_list low_timer;
 	u32 cc_lsb;		/* μAms per LSB */
 	atomic_t active;
 	int charge_full;
@@ -914,9 +915,14 @@ static irqreturn_t cpcap_battery_irq_thread(int irq, void *data)
 		dev_info(ddata->dev, "Coulomb counter calibration done\n");
 		break;
 	case CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW:
-		if (latest->current_ua >= 0)
+		if (latest->current_ua >= 0 &&
+		    !timer_pending(&ddata->low_timer)) {
 			dev_warn(ddata->dev, "Battery low at %imV!\n",
 				latest->voltage / 1000);
+			mod_timer(&ddata->low_timer,
+				  jiffies + msecs_to_jiffies(30000));
+			disable_irq_nosync(d->irq);
+		}
 		break;
 	case CPCAP_BATTERY_IRQ_ACTION_POWEROFF:
 		if (latest->current_ua >= 0 && latest->voltage <= 3200000) {
@@ -1087,6 +1093,19 @@ static int cpcap_battery_calibrate(struct cpcap_battery_ddata *ddata)
 	return error;
 }
 
+static void cpcap_battery_lowbph_enable(struct timer_list *t)
+{
+	struct cpcap_battery_ddata *ddata = from_timer(ddata, t, low_timer);
+	struct cpcap_interrupt_desc *d;
+
+	list_for_each_entry(d, &ddata->irq_list, node) {
+		if (d->action == CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW)
+			break;
+	}
+
+	enable_irq(d->irq);
+}
+
 #ifdef CONFIG_OF
 static const struct of_device_id cpcap_battery_id_table[] = {
 	{
@@ -1118,6 +1137,8 @@ static int cpcap_battery_probe(struct platform_device *pdev)
 	if (!ddata)
 		return -ENOMEM;
 
+	timer_setup(&ddata->low_timer, cpcap_battery_lowbph_enable, 0);
+
 	cpcap_battery_detect_battery_type(ddata);
 
 	INIT_LIST_HEAD(&ddata->irq_list);
@@ -1185,6 +1206,8 @@ static int cpcap_battery_remove(struct platform_device *pdev)
 	if (error)
 		dev_err(&pdev->dev, "could not disable: %i\n", error);
 
+	del_timer_sync(&ddata->low_timer);
+
 	return 0;
 }
 
-- 
1.9.1

[PATCH 2/3] power: supply: cpcap-battery: Fix battery identification

[Ivaylo Dimitrov]

Use the same logic to identify genuine batteries as Android does.

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
---
 drivers/power/supply/cpcap-battery.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
index 2659df7..4cfc325 100644
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -422,7 +422,7 @@ static int cpcap_battery_cc_to_ua(struct cpcap_battery_ddata *ddata,
 
 static int cpcap_battery_match_nvmem(struct device *dev, const void *data)
 {
-	if (strcmp(dev_name(dev), "89-500029ba0f73") == 0)
+	if (strncmp(dev_name(dev), "89-500", 6) == 0)
 		return 1;
 	else
 		return 0;
@@ -439,10 +439,19 @@ static void cpcap_battery_detect_battery_type(struct cpcap_battery_ddata *ddata)
 	if (IS_ERR_OR_NULL(nvmem)) {
 		ddata->check_nvmem = true;
 		dev_info_once(ddata->dev, "Can not find battery nvmem device. Assuming generic lipo battery\n");
-	} else if (nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) {
-		battery_id = 0;
-		ddata->check_nvmem = true;
-		dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n");
+	} else {
+		char buf[24];
+
+		if (nvmem_device_read(nvmem, 96, 4, buf) < 0 ||
+		    strncmp(buf, "COPR", 4) != 0 ||
+		    nvmem_device_read(nvmem, 104, 24, buf) < 0 ||
+		    strncmp(buf, "MOTOROLA E.P CHARGE ONLY", 24) != 0 ||
+		    nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) {
+			battery_id = 0;
+			ddata->check_nvmem = true;
+			dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n");
+		}
+
 	}
 
 	switch (battery_id) {
-- 
1.9.1

[PATCH 3/3] power: supply: cpcap_battery: Read battery parameters from nvram

[Ivaylo Dimitrov]

Formulas were taken from android blob

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
---
 drivers/power/supply/cpcap-battery.c | 88 ++++++++++++++++++++----------------
 1 file changed, 48 insertions(+), 40 deletions(-)

diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
index 4cfc325..5c51685 100644
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -74,9 +74,6 @@
 
 #define CPCAP_BATTERY_CC_SAMPLE_PERIOD_MS	250
 
-#define CPCAP_BATTERY_EB41_HW4X_ID 0x9E
-#define CPCAP_BATTERY_BW8X_ID 0x98
-
 enum {
 	CPCAP_BATTERY_IIO_BATTDET,
 	CPCAP_BATTERY_IIO_VOLTAGE,
@@ -388,22 +385,9 @@ static int cpcap_battery_cc_to_ua(struct cpcap_battery_ddata *ddata,
  * kernel on droid 4, full is 4351000 and software initiates shutdown
  * at 3078000. The device will die around 2743000.
  */
-static const struct cpcap_battery_config cpcap_battery_eb41_data = {
-	.cd_factor = 0x3cc,
-	.info.technology = POWER_SUPPLY_TECHNOLOGY_LION,
-	.info.voltage_max_design = 4351000,
-	.info.voltage_min_design = 3100000,
-	.info.charge_full_design = 1740000,
-	.bat.constant_charge_voltage_max_uv = 4200000,
-};
-
-/* Values for the extended Droid Bionic battery bw8x. */
-static const struct cpcap_battery_config cpcap_battery_bw8x_data = {
+static struct cpcap_battery_config cpcap_battery_mot_data = {
 	.cd_factor = 0x3cc,
 	.info.technology = POWER_SUPPLY_TECHNOLOGY_LION,
-	.info.voltage_max_design = 4200000,
-	.info.voltage_min_design = 3200000,
-	.info.charge_full_design = 2760000,
 	.bat.constant_charge_voltage_max_uv = 4200000,
 };
 
@@ -431,39 +415,63 @@ static int cpcap_battery_match_nvmem(struct device *dev, const void *data)
 static void cpcap_battery_detect_battery_type(struct cpcap_battery_ddata *ddata)
 {
 	struct nvmem_device *nvmem;
-	u8 battery_id = 0;
+	char buf[24];
+	u8 capacity;
+	u8 mul_idx;
+	u8 charge_voltage;
+	u32 v;
+	static const u32 multipliers[] = {20, 10, 10, 10, 10, 40, 10, 20, 40};
 
 	ddata->check_nvmem = false;
 
 	nvmem = nvmem_device_find(NULL, &cpcap_battery_match_nvmem);
 	if (IS_ERR_OR_NULL(nvmem)) {
-		ddata->check_nvmem = true;
 		dev_info_once(ddata->dev, "Can not find battery nvmem device. Assuming generic lipo battery\n");
-	} else {
-		char buf[24];
-
-		if (nvmem_device_read(nvmem, 96, 4, buf) < 0 ||
-		    strncmp(buf, "COPR", 4) != 0 ||
-		    nvmem_device_read(nvmem, 104, 24, buf) < 0 ||
-		    strncmp(buf, "MOTOROLA E.P CHARGE ONLY", 24) != 0 ||
-		    nvmem_device_read(nvmem, 2, 1, &battery_id) < 0) {
-			battery_id = 0;
-			ddata->check_nvmem = true;
-			dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n");
-		}
+		goto unknown;
+	}
 
+	if (nvmem_device_read(nvmem, 96, 4, buf) < 0 ||
+	    strncmp(buf, "COPR", 4) != 0 ||
+	    nvmem_device_read(nvmem, 104, 24, buf) < 0 ||
+	    strncmp(buf, "MOTOROLA E.P CHARGE ONLY", 24) != 0) {
+		dev_warn(ddata->dev, "Unknown battery nvmem device. Assuming generic lipo battery\n");
+		goto unknown;
 	}
 
-	switch (battery_id) {
-	case CPCAP_BATTERY_EB41_HW4X_ID:
-		ddata->config = cpcap_battery_eb41_data;
-		break;
-	case CPCAP_BATTERY_BW8X_ID:
-		ddata->config = cpcap_battery_bw8x_data;
-		break;
-	default:
-		ddata->config = cpcap_battery_unkown_data;
+	if (nvmem_device_read(nvmem, 49, 1, &mul_idx) < 0 ||
+	    nvmem_device_read(nvmem, 34, 1, &capacity) < 0 ||
+	    nvmem_device_read(nvmem, 65, 1, &charge_voltage) < 0) {
+		dev_warn(ddata->dev, "Can not read battery nvmem device. Assuming generic lipo battery\n");
+		goto unknown;
 	}
+
+	/* design capacity */
+	mul_idx -= 2;
+
+	if (mul_idx < ARRAY_SIZE(multipliers))
+		v = multipliers[mul_idx];
+	else
+		v = 10;
+
+	cpcap_battery_mot_data.info.charge_full_design = 1000 * v * capacity;
+
+	/* design max voltage */
+	v = 1000 * ((16702 * charge_voltage) / 1000 + 1260);
+	cpcap_battery_mot_data.info.voltage_max_design = v;
+
+	/* design min voltage */
+	if (v > 4200000)
+		cpcap_battery_mot_data.info.voltage_min_design = 3100000;
+	else
+		cpcap_battery_mot_data.info.voltage_min_design = 3200000;
+
+	ddata->config = cpcap_battery_mot_data;
+
+	return;
+
+unknown:
+	ddata->check_nvmem = true;
+	ddata->config = cpcap_battery_unkown_data;
 }
 
 /**
-- 
1.9.1

Re: [PATCH 1/3] power: cpcap-battery: Do not issue low signal too frequently

[Ivaylo Dimitrov]

This patch has issues (calling enable_irq() from timer function), will 
send v2 that uses delayed_work.

On 1.11.22 г. 21:53 ч., Ivaylo Dimitrov wrote:
> It seems that low battery irq may be generated tens of times per second,
> leading to userspace being flooded with unnecessary events.
> 
> Fix that by preventing such events being generated more than once every 30
> seconds.
> 
> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
> ---
>   drivers/power/supply/cpcap-battery.c | 25 ++++++++++++++++++++++++-
>   1 file changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
> index 4676560..2659df7 100644
> --- a/drivers/power/supply/cpcap-battery.c
> +++ b/drivers/power/supply/cpcap-battery.c
> @@ -137,6 +137,7 @@ struct cpcap_battery_ddata {
>   	struct power_supply *psy;
>   	struct cpcap_battery_config config;
>   	struct cpcap_battery_state_data state[CPCAP_BATTERY_STATE_NR];
> +	struct timer_list low_timer;
>   	u32 cc_lsb;		/* μAms per LSB */
>   	atomic_t active;
>   	int charge_full;
> @@ -914,9 +915,14 @@ static irqreturn_t cpcap_battery_irq_thread(int irq, void *data)
>   		dev_info(ddata->dev, "Coulomb counter calibration done\n");
>   		break;
>   	case CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW:
> -		if (latest->current_ua >= 0)
> +		if (latest->current_ua >= 0 &&
> +		    !timer_pending(&ddata->low_timer)) {
>   			dev_warn(ddata->dev, "Battery low at %imV!\n",
>   				latest->voltage / 1000);
> +			mod_timer(&ddata->low_timer,
> +				  jiffies + msecs_to_jiffies(30000));
> +			disable_irq_nosync(d->irq);
> +		}
>   		break;
>   	case CPCAP_BATTERY_IRQ_ACTION_POWEROFF:
>   		if (latest->current_ua >= 0 && latest->voltage <= 3200000) {
> @@ -1087,6 +1093,19 @@ static int cpcap_battery_calibrate(struct cpcap_battery_ddata *ddata)
>   	return error;
>   }
>   
> +static void cpcap_battery_lowbph_enable(struct timer_list *t)
> +{
> +	struct cpcap_battery_ddata *ddata = from_timer(ddata, t, low_timer);
> +	struct cpcap_interrupt_desc *d;
> +
> +	list_for_each_entry(d, &ddata->irq_list, node) {
> +		if (d->action == CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW)
> +			break;
> +	}
> +
> +	enable_irq(d->irq);
> +}
> +
>   #ifdef CONFIG_OF
>   static const struct of_device_id cpcap_battery_id_table[] = {
>   	{
> @@ -1118,6 +1137,8 @@ static int cpcap_battery_probe(struct platform_device *pdev)
>   	if (!ddata)
>   		return -ENOMEM;
>   
> +	timer_setup(&ddata->low_timer, cpcap_battery_lowbph_enable, 0);
> +
>   	cpcap_battery_detect_battery_type(ddata);
>   
>   	INIT_LIST_HEAD(&ddata->irq_list);
> @@ -1185,6 +1206,8 @@ static int cpcap_battery_remove(struct platform_device *pdev)
>   	if (error)
>   		dev_err(&pdev->dev, "could not disable: %i\n", error);
>   
> +	del_timer_sync(&ddata->low_timer);
> +
>   	return 0;
>   }
>   
>