[v2] power: bq24735-charger: Request status GPIO with initial input setup

Submitted by Paul Kocialkowski on Aug. 29, 2016, 6:15 p.m.

Details

Message ID 20160829181503.9590-1-contact@paulk.fr
State New
Headers show

Commit Message

Paul Kocialkowski Aug. 29, 2016, 6:15 p.m.
This requests the status GPIO with initial input setup. it is required
to read the GPIO status at probe time and thus correctly avoid sending
i2c messages when AC is not plugged.

When requesting the GPIO without initial input setup, it always reads 0
which causes probe to fail as it assumes the charger is connected, sends
i2c messages and fails.

While at it, this switches the driver over to devm and gpio consumer.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
---
 drivers/power/bq24735-charger.c       | 29 +++++++----------------------
 include/linux/power/bq24735-charger.h |  3 +--
 2 files changed, 8 insertions(+), 24 deletions(-)

Comments

Sebastian Reichel Aug. 29, 2016, 11:32 p.m.
Hi,

On Mon, Aug 29, 2016 at 08:15:03PM +0200, Paul Kocialkowski wrote:
> This requests the status GPIO with initial input setup. it is required
> to read the GPIO status at probe time and thus correctly avoid sending
> i2c messages when AC is not plugged.
> 
> When requesting the GPIO without initial input setup, it always reads 0
> which causes probe to fail as it assumes the charger is connected, sends
> i2c messages and fails.

That looks mostly fine. I have some more comments, though.

> While at it, this switches the driver over to devm and gpio consumer.

NIT: the driver was already using devm previously

> Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
> ---
>  drivers/power/bq24735-charger.c       | 29 +++++++----------------------
>  include/linux/power/bq24735-charger.h |  3 +--
>  2 files changed, 8 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/power/bq24735-charger.c b/drivers/power/bq24735-charger.c
> index dc460bb..5744a88 100644
> --- a/drivers/power/bq24735-charger.c
> +++ b/drivers/power/bq24735-charger.c
> @@ -25,7 +25,8 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> -#include <linux/of_gpio.h>
> +#include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/power_supply.h>
>  #include <linux/slab.h>
>  
> @@ -181,8 +182,8 @@ static bool bq24735_charger_is_present(struct bq24735 *charger)
>  	int ret;
>  
>  	if (pdata->status_gpio_valid) {
> -		ret = gpio_get_value_cansleep(pdata->status_gpio);
> -		return ret ^= pdata->status_gpio_active_low == 0;
> +		ret = gpiod_get_value_cansleep(pdata->status_gpio);
> +		return ret ^= gpiod_is_active_low(pdata->status_gpio) == 0;

This looks fishy. The gpiod API outputs converted values already (if
one does not use the raw variant). I think you want to do:

return !gpiod_get_value_cansleep(pdata->status_gpio);

>  	} else {
>  		int ac = 0;
>  
> @@ -308,7 +309,6 @@ static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
>  	struct device_node *np = client->dev.of_node;
>  	u32 val;
>  	int ret;
> -	enum of_gpio_flags flags;
>  
>  	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
>  	if (!pdata) {
> @@ -317,11 +317,9 @@ static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
>  		return NULL;
>  	}
>  
> -	pdata->status_gpio = of_get_named_gpio_flags(np, "ti,ac-detect-gpios",
> -						     0, &flags);
> -
> -	if (flags & OF_GPIO_ACTIVE_LOW)
> -		pdata->status_gpio_active_low = 1;
> +	pdata->status_gpio = devm_gpiod_get(&client->dev, "ti,ac-detect",
> +						GPIOD_IN);
> +	pdata->status_gpio_valid = !IS_ERR(pdata->status_gpio);

Just use devm_gpiod_get_optional(). Then instead of
checking if (pdata->status_gpio_valid) you do
if (pdata->status_gpio).

Also you should check for EPROBE_DEFER. With the
_optional() change you can just do

if (IS_ERR(pdata->status_gpio)) {
    ret = PTR_ERR(pdata->status_gpio);
    dev_err(&client->dev, "Could not get gpio: %d\n", ret);
    return ret;
}

>  	ret = of_property_read_u32(np, "ti,charge-current", &val);
>  	if (!ret)
> @@ -396,19 +394,6 @@ static int bq24735_charger_probe(struct i2c_client *client,
>  
>  	i2c_set_clientdata(client, charger);
>  
> -	if (gpio_is_valid(charger->pdata->status_gpio)) {
> -		ret = devm_gpio_request(&client->dev,
> -					charger->pdata->status_gpio,
> -					name);
> -		if (ret) {
> -			dev_err(&client->dev,
> -				"Failed GPIO request for GPIO %d: %d\n",
> -				charger->pdata->status_gpio, ret);
> -		}
> -
> -		charger->pdata->status_gpio_valid = !ret;
> -	}
> -
>  	if (!charger->pdata->status_gpio_valid
>  	    || bq24735_charger_is_present(charger)) {
>  		ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
> diff --git a/include/linux/power/bq24735-charger.h b/include/linux/power/bq24735-charger.h
> index 6b750c1a..bbc284e 100644
> --- a/include/linux/power/bq24735-charger.h
> +++ b/include/linux/power/bq24735-charger.h
> @@ -28,8 +28,7 @@ struct bq24735_platform {
>  
>  	const char *name;
>  
> -	int status_gpio;
> -	int status_gpio_active_low;
> +	struct gpio_desc *status_gpio;
>  	bool status_gpio_valid;
>  
>  	bool ext_control;

Otherwise looks fine.

-- Sebastian
Paul Kocialkowski Sept. 1, 2016, 9:41 p.m.
Le mardi 30 août 2016 à 01:32 +0200, Sebastian Reichel a écrit :
> Hi,
> 
> On Mon, Aug 29, 2016 at 08:15:03PM +0200, Paul Kocialkowski wrote:
> > 
> > This requests the status GPIO with initial input setup. it is required
> > to read the GPIO status at probe time and thus correctly avoid sending
> > i2c messages when AC is not plugged.
> > 
> > When requesting the GPIO without initial input setup, it always reads 0
> > which causes probe to fail as it assumes the charger is connected, sends
> > i2c messages and fails.
> 
> That looks mostly fine. I have some more comments, though.

Thanks for the review, v3 sent. Feel free to add your Signed-off-by line since
your suggestions heavily influenced v3!

> > While at it, this switches the driver over to devm and gpio consumer.
> 
> NIT: the driver was already using devm previously
> 
> > 
> > Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
> > ---
> >  drivers/power/bq24735-charger.c       | 29 +++++++----------------------
> >  include/linux/power/bq24735-charger.h |  3 +--
> >  2 files changed, 8 insertions(+), 24 deletions(-)
> > 
> > diff --git a/drivers/power/bq24735-charger.c b/drivers/power/bq24735-
> > charger.c
> > index dc460bb..5744a88 100644
> > --- a/drivers/power/bq24735-charger.c
> > +++ b/drivers/power/bq24735-charger.c
> > @@ -25,7 +25,8 @@
> >  #include <linux/kernel.h>
> >  #include <linux/module.h>
> >  #include <linux/of.h>
> > -#include <linux/of_gpio.h>
> > +#include <linux/gpio.h>
> > +#include <linux/gpio/consumer.h>
> >  #include <linux/power_supply.h>
> >  #include <linux/slab.h>
> >  
> > @@ -181,8 +182,8 @@ static bool bq24735_charger_is_present(struct bq24735
> > *charger)
> >  	int ret;
> >  
> >  	if (pdata->status_gpio_valid) {
> > -		ret = gpio_get_value_cansleep(pdata->status_gpio);
> > -		return ret ^= pdata->status_gpio_active_low == 0;
> > +		ret = gpiod_get_value_cansleep(pdata->status_gpio);
> > +		return ret ^= gpiod_is_active_low(pdata->status_gpio) == 0;
> 
> This looks fishy. The gpiod API outputs converted values already (if
> one does not use the raw variant). I think you want to do:
> 
> return !gpiod_get_value_cansleep(pdata->status_gpio);
> 
> > 
> >  	} else {
> >  		int ac = 0;
> >  
> > @@ -308,7 +309,6 @@ static struct bq24735_platform
> > *bq24735_parse_dt_data(struct i2c_client *client)
> >  	struct device_node *np = client->dev.of_node;
> >  	u32 val;
> >  	int ret;
> > -	enum of_gpio_flags flags;
> >  
> >  	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
> >  	if (!pdata) {
> > @@ -317,11 +317,9 @@ static struct bq24735_platform
> > *bq24735_parse_dt_data(struct i2c_client *client)
> >  		return NULL;
> >  	}
> >  
> > -	pdata->status_gpio = of_get_named_gpio_flags(np, "ti,ac-detect-
> > gpios",
> > -						     0, &flags);
> > -
> > -	if (flags & OF_GPIO_ACTIVE_LOW)
> > -		pdata->status_gpio_active_low = 1;
> > +	pdata->status_gpio = devm_gpiod_get(&client->dev, "ti,ac-detect",
> > +						GPIOD_IN);
> > +	pdata->status_gpio_valid = !IS_ERR(pdata->status_gpio);
> 
> Just use devm_gpiod_get_optional(). Then instead of
> checking if (pdata->status_gpio_valid) you do
> if (pdata->status_gpio).
> 
> Also you should check for EPROBE_DEFER. With the
> _optional() change you can just do
> 
> if (IS_ERR(pdata->status_gpio)) {
>     ret = PTR_ERR(pdata->status_gpio);
>     dev_err(&client->dev, "Could not get gpio: %d\n", ret);
>     return ret;
> }
> 
> > 
> >  	ret = of_property_read_u32(np, "ti,charge-current", &val);
> >  	if (!ret)
> > @@ -396,19 +394,6 @@ static int bq24735_charger_probe(struct i2c_client
> > *client,
> >  
> >  	i2c_set_clientdata(client, charger);
> >  
> > -	if (gpio_is_valid(charger->pdata->status_gpio)) {
> > -		ret = devm_gpio_request(&client->dev,
> > -					charger->pdata->status_gpio,
> > -					name);
> > -		if (ret) {
> > -			dev_err(&client->dev,
> > -				"Failed GPIO request for GPIO %d: %d\n",
> > -				charger->pdata->status_gpio, ret);
> > -		}
> > -
> > -		charger->pdata->status_gpio_valid = !ret;
> > -	}
> > -
> >  	if (!charger->pdata->status_gpio_valid
> >  	    || bq24735_charger_is_present(charger)) {
> >  		ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
> > diff --git a/include/linux/power/bq24735-charger.h
> > b/include/linux/power/bq24735-charger.h
> > index 6b750c1a..bbc284e 100644
> > --- a/include/linux/power/bq24735-charger.h
> > +++ b/include/linux/power/bq24735-charger.h
> > @@ -28,8 +28,7 @@ struct bq24735_platform {
> >  
> >  	const char *name;
> >  
> > -	int status_gpio;
> > -	int status_gpio_active_low;
> > +	struct gpio_desc *status_gpio;
> >  	bool status_gpio_valid;
> >  
> >  	bool ext_control;
> 
> Otherwise looks fine.
> 
> -- Sebastian

Patch hide | download patch | download mbox

diff --git a/drivers/power/bq24735-charger.c b/drivers/power/bq24735-charger.c
index dc460bb..5744a88 100644
--- a/drivers/power/bq24735-charger.c
+++ b/drivers/power/bq24735-charger.c
@@ -25,7 +25,8 @@ 
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/power_supply.h>
 #include <linux/slab.h>
 
@@ -181,8 +182,8 @@  static bool bq24735_charger_is_present(struct bq24735 *charger)
 	int ret;
 
 	if (pdata->status_gpio_valid) {
-		ret = gpio_get_value_cansleep(pdata->status_gpio);
-		return ret ^= pdata->status_gpio_active_low == 0;
+		ret = gpiod_get_value_cansleep(pdata->status_gpio);
+		return ret ^= gpiod_is_active_low(pdata->status_gpio) == 0;
 	} else {
 		int ac = 0;
 
@@ -308,7 +309,6 @@  static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
 	struct device_node *np = client->dev.of_node;
 	u32 val;
 	int ret;
-	enum of_gpio_flags flags;
 
 	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
 	if (!pdata) {
@@ -317,11 +317,9 @@  static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client)
 		return NULL;
 	}
 
-	pdata->status_gpio = of_get_named_gpio_flags(np, "ti,ac-detect-gpios",
-						     0, &flags);
-
-	if (flags & OF_GPIO_ACTIVE_LOW)
-		pdata->status_gpio_active_low = 1;
+	pdata->status_gpio = devm_gpiod_get(&client->dev, "ti,ac-detect",
+						GPIOD_IN);
+	pdata->status_gpio_valid = !IS_ERR(pdata->status_gpio);
 
 	ret = of_property_read_u32(np, "ti,charge-current", &val);
 	if (!ret)
@@ -396,19 +394,6 @@  static int bq24735_charger_probe(struct i2c_client *client,
 
 	i2c_set_clientdata(client, charger);
 
-	if (gpio_is_valid(charger->pdata->status_gpio)) {
-		ret = devm_gpio_request(&client->dev,
-					charger->pdata->status_gpio,
-					name);
-		if (ret) {
-			dev_err(&client->dev,
-				"Failed GPIO request for GPIO %d: %d\n",
-				charger->pdata->status_gpio, ret);
-		}
-
-		charger->pdata->status_gpio_valid = !ret;
-	}
-
 	if (!charger->pdata->status_gpio_valid
 	    || bq24735_charger_is_present(charger)) {
 		ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID);
diff --git a/include/linux/power/bq24735-charger.h b/include/linux/power/bq24735-charger.h
index 6b750c1a..bbc284e 100644
--- a/include/linux/power/bq24735-charger.h
+++ b/include/linux/power/bq24735-charger.h
@@ -28,8 +28,7 @@  struct bq24735_platform {
 
 	const char *name;
 
-	int status_gpio;
-	int status_gpio_active_low;
+	struct gpio_desc *status_gpio;
 	bool status_gpio_valid;
 
 	bool ext_control;