diff mbox

usb: phy: Cleanup error code in **_usb_get_phy_**() APIs

Message ID 1375880938-6979-1-git-send-email-gautam.vivek@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Vivek Gautam Aug. 7, 2013, 1:08 p.m. UTC
**_usb_get_phy_**() APIs should generate equivalent
error codes in case of failure in getting phy. There's no
need of returning NULL pointer, like in devm_usb_get_phy()
or devm_usb_get_phy_dev(), since it's nowhere handled.

Earlier series of patches starting:
9ee1c7f usb: host: ohci-exynos: fix PHY error handling,
fixed PHY error handling.

Also adding error handling in usb_phy_**() APIs.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
---
 drivers/usb/phy/phy.c   |   18 ++++++++++--------
 include/linux/usb/phy.h |   42 ++++++++++++++++++++++--------------------
 2 files changed, 32 insertions(+), 28 deletions(-)

Comments

Julius Werner Aug. 7, 2013, 6:35 p.m. UTC | #1
> @@ -94,11 +94,11 @@ static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
>   */
>  struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
>  {
> -       struct usb_phy **ptr, *phy;
> +       struct usb_phy  *phy = ERR_PTR(-ENOMEM), **ptr;

This looks a little roundabout, don't you think? Why don't you just
directly have 'return ERR_PTR(-ENOMEM)' down there where you put 'goto
err0'?

>
>         ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
>         if (!ptr)
> -               return NULL;
> +               goto err0;
>
>         phy = usb_get_phy(type);
>         if (!IS_ERR(phy)) {
> @@ -107,6 +107,7 @@ struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
>         } else
>                 devres_free(ptr);
>
> +err0:
>         return phy;
>  }
>  EXPORT_SYMBOL_GPL(devm_usb_get_phy);

>  struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index)
>  {
> -       struct usb_phy **ptr, *phy;
> +       struct usb_phy  *phy = ERR_PTR(-ENOMEM), **ptr;

Same here

>
>         ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
>         if (!ptr)
> -               return NULL;
> +               goto err0;
>
>         phy = usb_get_phy_dev(dev, index);
>         if (!IS_ERR(phy)) {
> @@ -267,6 +268,7 @@ struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index)
>         } else
>                 devres_free(ptr);
>
> +err0:
>         return phy;
>  }
>  EXPORT_SYMBOL_GPL(devm_usb_get_phy_dev);

> @@ -142,7 +142,7 @@ extern void usb_remove_phy(struct usb_phy *);
>  /* helpers for direct access thru low-level io interface */
>  static inline int usb_phy_io_read(struct usb_phy *x, u32 reg)
>  {
> -       if (x->io_ops && x->io_ops->read)
> +       if (!IS_ERR(x) && x->io_ops && x->io_ops->read)

I liked the ones where we had IS_ERR_OR_NULL() here (and in all the
ones below)... you sometimes have to handle PHYs in
platform-independent code where you don't want to worry about if this
platform actually has a PHY driver there or not. Any reason you
changed that?

>                 return x->io_ops->read(x, reg);
>
>         return -EINVAL;
> @@ -150,7 +150,7 @@ static inline int usb_phy_io_read(struct usb_phy *x, u32 reg)
>
>  static inline int usb_phy_io_write(struct usb_phy *x, u32 val, u32 reg)
>  {
> -       if (x->io_ops && x->io_ops->write)
> +       if (!IS_ERR(x) && x->io_ops && x->io_ops->write)
>                 return x->io_ops->write(x, val, reg);
>
>         return -EINVAL;
> @@ -159,7 +159,7 @@ static inline int usb_phy_io_write(struct usb_phy *x, u32 val, u32 reg)
>  static inline int
>  usb_phy_init(struct usb_phy *x)
>  {
> -       if (x->init)
> +       if (!IS_ERR(x) && x->init)
>                 return x->init(x);
>
>         return 0;
> @@ -168,26 +168,27 @@ usb_phy_init(struct usb_phy *x)
>  static inline void
>  usb_phy_shutdown(struct usb_phy *x)
>  {
> -       if (x->shutdown)
> +       if (!IS_ERR(x) && x->shutdown)
>                 x->shutdown(x);
>  }
>
>  static inline int
>  usb_phy_vbus_on(struct usb_phy *x)
>  {
> -       if (!x->set_vbus)
> -               return 0;
> +       if (!IS_ERR(x) && x->set_vbus)
> +               return x->set_vbus(x, true);
>
> -       return x->set_vbus(x, true);
> +       return 0;
>  }
>
>  static inline int
>  usb_phy_vbus_off(struct usb_phy *x)
>  {
> -       if (!x->set_vbus)
> -               return 0;
> +       if (!IS_ERR(x) && x->set_vbus)
> +               return x->set_vbus(x, false);
> +
> +       return 0;
>
> -       return x->set_vbus(x, false);
>  }
>
>  /* for usb host and peripheral controller drivers */
> @@ -249,8 +250,9 @@ static inline int usb_bind_phy(const char *dev_name, u8 index,
>  static inline int
>  usb_phy_set_power(struct usb_phy *x, unsigned mA)
>  {
> -       if (x && x->set_power)
> +       if (!IS_ERR(x) && x->set_power)
>                 return x->set_power(x, mA);
> +
>         return 0;
>  }
>
> @@ -258,28 +260,28 @@ usb_phy_set_power(struct usb_phy *x, unsigned mA)
>  static inline int
>  usb_phy_set_suspend(struct usb_phy *x, int suspend)
>  {
> -       if (x->set_suspend != NULL)
> +       if (!IS_ERR(x) && x->set_suspend != NULL)
>                 return x->set_suspend(x, suspend);
> -       else
> -               return 0;
> +
> +       return 0;
>  }
>
>  static inline int
>  usb_phy_notify_connect(struct usb_phy *x, enum usb_device_speed speed)
>  {
> -       if (x->notify_connect)
> +       if (!IS_ERR(x) && x->notify_connect)
>                 return x->notify_connect(x, speed);
> -       else
> -               return 0;
> +
> +       return 0;
>  }
>
>  static inline int
>  usb_phy_notify_disconnect(struct usb_phy *x, enum usb_device_speed speed)
>  {
> -       if (x->notify_disconnect)
> +       if (!IS_ERR(x) && x->notify_disconnect)
>                 return x->notify_disconnect(x, speed);
> -       else
> -               return 0;
> +
> +       return 0;
>  }

Otherwise looks good to me.
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Vivek Gautam Aug. 19, 2013, 2:40 a.m. UTC | #2
Hi,


On Thu, Aug 8, 2013 at 12:05 AM, Julius Werner <jwerner@chromium.org> wrote:
>> @@ -94,11 +94,11 @@ static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
>>   */
>>  struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
>>  {
>> -       struct usb_phy **ptr, *phy;
>> +       struct usb_phy  *phy = ERR_PTR(-ENOMEM), **ptr;
>
> This looks a little roundabout, don't you think? Why don't you just
> directly have 'return ERR_PTR(-ENOMEM)' down there where you put 'goto
> err0'?

Ok, will change this.

>
>>
>>         ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
>>         if (!ptr)
>> -               return NULL;
>> +               goto err0;
>>
>>         phy = usb_get_phy(type);
>>         if (!IS_ERR(phy)) {
>> @@ -107,6 +107,7 @@ struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
>>         } else
>>                 devres_free(ptr);
>>
>> +err0:
>>         return phy;
>>  }
>>  EXPORT_SYMBOL_GPL(devm_usb_get_phy);
>
>>  struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index)
>>  {
>> -       struct usb_phy **ptr, *phy;
>> +       struct usb_phy  *phy = ERR_PTR(-ENOMEM), **ptr;
>
> Same here

will change this too.

>
>>
>>         ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
>>         if (!ptr)
>> -               return NULL;
>> +               goto err0;
>>
>>         phy = usb_get_phy_dev(dev, index);
>>         if (!IS_ERR(phy)) {
>> @@ -267,6 +268,7 @@ struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index)
>>         } else
>>                 devres_free(ptr);
>>
>> +err0:
>>         return phy;
>>  }
>>  EXPORT_SYMBOL_GPL(devm_usb_get_phy_dev);
>
>> @@ -142,7 +142,7 @@ extern void usb_remove_phy(struct usb_phy *);
>>  /* helpers for direct access thru low-level io interface */
>>  static inline int usb_phy_io_read(struct usb_phy *x, u32 reg)
>>  {
>> -       if (x->io_ops && x->io_ops->read)
>> +       if (!IS_ERR(x) && x->io_ops && x->io_ops->read)
>
> I liked the ones where we had IS_ERR_OR_NULL() here (and in all the
> ones below)... you sometimes have to handle PHYs in
> platform-independent code where you don't want to worry about if this
> platform actually has a PHY driver there or not. Any reason you
> changed that?

The **get_phy_*() APIs never return a NULL pointer now, do we still
need to handle that in that case.
Or are we assuming that code will use these phy operations without
getting a phy in the first place ?

>
>>                 return x->io_ops->read(x, reg);
>>
>>         return -EINVAL;
>> @@ -150,7 +150,7 @@ static inline int usb_phy_io_read(struct usb_phy *x, u32 reg)
>>
>>  static inline int usb_phy_io_write(struct usb_phy *x, u32 val, u32 reg)
>>  {
>> -       if (x->io_ops && x->io_ops->write)
>> +       if (!IS_ERR(x) && x->io_ops && x->io_ops->write)
>>                 return x->io_ops->write(x, val, reg);
>>
>>         return -EINVAL;
>> @@ -159,7 +159,7 @@ static inline int usb_phy_io_write(struct usb_phy *x, u32 val, u32 reg)
>>  static inline int
>>  usb_phy_init(struct usb_phy *x)
>>  {
>> -       if (x->init)
>> +       if (!IS_ERR(x) && x->init)
>>                 return x->init(x);
>>
>>         return 0;
>> @@ -168,26 +168,27 @@ usb_phy_init(struct usb_phy *x)
>>  static inline void
>>  usb_phy_shutdown(struct usb_phy *x)
>>  {
>> -       if (x->shutdown)
>> +       if (!IS_ERR(x) && x->shutdown)
>>                 x->shutdown(x);
>>  }
>>
>>  static inline int
>>  usb_phy_vbus_on(struct usb_phy *x)
>>  {
>> -       if (!x->set_vbus)
>> -               return 0;
>> +       if (!IS_ERR(x) && x->set_vbus)
>> +               return x->set_vbus(x, true);
>>
>> -       return x->set_vbus(x, true);
>> +       return 0;
>>  }
>>
>>  static inline int
>>  usb_phy_vbus_off(struct usb_phy *x)
>>  {
>> -       if (!x->set_vbus)
>> -               return 0;
>> +       if (!IS_ERR(x) && x->set_vbus)
>> +               return x->set_vbus(x, false);
>> +
>> +       return 0;
>>
>> -       return x->set_vbus(x, false);
>>  }
>>
>>  /* for usb host and peripheral controller drivers */
>> @@ -249,8 +250,9 @@ static inline int usb_bind_phy(const char *dev_name, u8 index,
>>  static inline int
>>  usb_phy_set_power(struct usb_phy *x, unsigned mA)
>>  {
>> -       if (x && x->set_power)
>> +       if (!IS_ERR(x) && x->set_power)
>>                 return x->set_power(x, mA);
>> +
>>         return 0;
>>  }
>>
>> @@ -258,28 +260,28 @@ usb_phy_set_power(struct usb_phy *x, unsigned mA)
>>  static inline int
>>  usb_phy_set_suspend(struct usb_phy *x, int suspend)
>>  {
>> -       if (x->set_suspend != NULL)
>> +       if (!IS_ERR(x) && x->set_suspend != NULL)
>>                 return x->set_suspend(x, suspend);
>> -       else
>> -               return 0;
>> +
>> +       return 0;
>>  }
>>
>>  static inline int
>>  usb_phy_notify_connect(struct usb_phy *x, enum usb_device_speed speed)
>>  {
>> -       if (x->notify_connect)
>> +       if (!IS_ERR(x) && x->notify_connect)
>>                 return x->notify_connect(x, speed);
>> -       else
>> -               return 0;
>> +
>> +       return 0;
>>  }
>>
>>  static inline int
>>  usb_phy_notify_disconnect(struct usb_phy *x, enum usb_device_speed speed)
>>  {
>> -       if (x->notify_disconnect)
>> +       if (!IS_ERR(x) && x->notify_disconnect)
>>                 return x->notify_disconnect(x, speed);
>> -       else
>> -               return 0;
>> +
>> +       return 0;
>>  }
>
> Otherwise looks good to me.

Thanks !!
Julius Werner Aug. 19, 2013, 6 p.m. UTC | #3
>> I liked the ones where we had IS_ERR_OR_NULL() here (and in all the
>> ones below)... you sometimes have to handle PHYs in
>> platform-independent code where you don't want to worry about if this
>> platform actually has a PHY driver there or not. Any reason you
>> changed that?
>
> The **get_phy_*() APIs never return a NULL pointer now, do we still
> need to handle that in that case.
> Or are we assuming that code will use these phy operations without
> getting a phy in the first place ?

In our 5420 PHY tune patch (which I think has not made it upstream
yet), we're calling usb_phy_tune(hcd->phy) from the USB core. This
pointer is usually NULL unless it has been explicitly set by the
platform specific HCD driver. For situations like that I think it's
convenient if you can just fire-and-forget a generic PHY method
without worrying whether the particular PHY implements it or whether
it has a driver at all.
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diff mbox

Patch

diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
index a9984c7..86f9905 100644
--- a/drivers/usb/phy/phy.c
+++ b/drivers/usb/phy/phy.c
@@ -25,7 +25,7 @@  static DEFINE_SPINLOCK(phy_lock);
 static struct usb_phy *__usb_find_phy(struct list_head *list,
 	enum usb_phy_type type)
 {
-	struct usb_phy  *phy = NULL;
+	struct usb_phy  *phy;
 
 	list_for_each_entry(phy, list, head) {
 		if (phy->type != type)
@@ -40,7 +40,7 @@  static struct usb_phy *__usb_find_phy(struct list_head *list,
 static struct usb_phy *__usb_find_phy_dev(struct device *dev,
 	struct list_head *list, u8 index)
 {
-	struct usb_phy_bind *phy_bind = NULL;
+	struct usb_phy_bind *phy_bind;
 
 	list_for_each_entry(phy_bind, list, list) {
 		if (!(strcmp(phy_bind->dev_name, dev_name(dev))) &&
@@ -94,11 +94,11 @@  static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
  */
 struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
 {
-	struct usb_phy **ptr, *phy;
+	struct usb_phy	*phy = ERR_PTR(-ENOMEM), **ptr;
 
 	ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
 	if (!ptr)
-		return NULL;
+		goto err0;
 
 	phy = usb_get_phy(type);
 	if (!IS_ERR(phy)) {
@@ -107,6 +107,7 @@  struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
 	} else
 		devres_free(ptr);
 
+err0:
 	return phy;
 }
 EXPORT_SYMBOL_GPL(devm_usb_get_phy);
@@ -123,7 +124,7 @@  EXPORT_SYMBOL_GPL(devm_usb_get_phy);
  */
 struct usb_phy *usb_get_phy(enum usb_phy_type type)
 {
-	struct usb_phy	*phy = NULL;
+	struct usb_phy	*phy;
 	unsigned long	flags;
 
 	spin_lock_irqsave(&phy_lock, flags);
@@ -221,7 +222,7 @@  EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle);
  */
 struct usb_phy *usb_get_phy_dev(struct device *dev, u8 index)
 {
-	struct usb_phy	*phy = NULL;
+	struct usb_phy	*phy;
 	unsigned long	flags;
 
 	spin_lock_irqsave(&phy_lock, flags);
@@ -254,11 +255,11 @@  EXPORT_SYMBOL_GPL(usb_get_phy_dev);
  */
 struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index)
 {
-	struct usb_phy **ptr, *phy;
+	struct usb_phy	*phy = ERR_PTR(-ENOMEM), **ptr;
 
 	ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
 	if (!ptr)
-		return NULL;
+		goto err0;
 
 	phy = usb_get_phy_dev(dev, index);
 	if (!IS_ERR(phy)) {
@@ -267,6 +268,7 @@  struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index)
 	} else
 		devres_free(ptr);
 
+err0:
 	return phy;
 }
 EXPORT_SYMBOL_GPL(devm_usb_get_phy_dev);
diff --git a/include/linux/usb/phy.h b/include/linux/usb/phy.h
index 4403680..9aa6aae 100644
--- a/include/linux/usb/phy.h
+++ b/include/linux/usb/phy.h
@@ -142,7 +142,7 @@  extern void usb_remove_phy(struct usb_phy *);
 /* helpers for direct access thru low-level io interface */
 static inline int usb_phy_io_read(struct usb_phy *x, u32 reg)
 {
-	if (x->io_ops && x->io_ops->read)
+	if (!IS_ERR(x) && x->io_ops && x->io_ops->read)
 		return x->io_ops->read(x, reg);
 
 	return -EINVAL;
@@ -150,7 +150,7 @@  static inline int usb_phy_io_read(struct usb_phy *x, u32 reg)
 
 static inline int usb_phy_io_write(struct usb_phy *x, u32 val, u32 reg)
 {
-	if (x->io_ops && x->io_ops->write)
+	if (!IS_ERR(x) && x->io_ops && x->io_ops->write)
 		return x->io_ops->write(x, val, reg);
 
 	return -EINVAL;
@@ -159,7 +159,7 @@  static inline int usb_phy_io_write(struct usb_phy *x, u32 val, u32 reg)
 static inline int
 usb_phy_init(struct usb_phy *x)
 {
-	if (x->init)
+	if (!IS_ERR(x) && x->init)
 		return x->init(x);
 
 	return 0;
@@ -168,26 +168,27 @@  usb_phy_init(struct usb_phy *x)
 static inline void
 usb_phy_shutdown(struct usb_phy *x)
 {
-	if (x->shutdown)
+	if (!IS_ERR(x) && x->shutdown)
 		x->shutdown(x);
 }
 
 static inline int
 usb_phy_vbus_on(struct usb_phy *x)
 {
-	if (!x->set_vbus)
-		return 0;
+	if (!IS_ERR(x) && x->set_vbus)
+		return x->set_vbus(x, true);
 
-	return x->set_vbus(x, true);
+	return 0;
 }
 
 static inline int
 usb_phy_vbus_off(struct usb_phy *x)
 {
-	if (!x->set_vbus)
-		return 0;
+	if (!IS_ERR(x) && x->set_vbus)
+		return x->set_vbus(x, false);
+
+	return 0;
 
-	return x->set_vbus(x, false);
 }
 
 /* for usb host and peripheral controller drivers */
@@ -249,8 +250,9 @@  static inline int usb_bind_phy(const char *dev_name, u8 index,
 static inline int
 usb_phy_set_power(struct usb_phy *x, unsigned mA)
 {
-	if (x && x->set_power)
+	if (!IS_ERR(x) && x->set_power)
 		return x->set_power(x, mA);
+
 	return 0;
 }
 
@@ -258,28 +260,28 @@  usb_phy_set_power(struct usb_phy *x, unsigned mA)
 static inline int
 usb_phy_set_suspend(struct usb_phy *x, int suspend)
 {
-	if (x->set_suspend != NULL)
+	if (!IS_ERR(x) && x->set_suspend != NULL)
 		return x->set_suspend(x, suspend);
-	else
-		return 0;
+
+	return 0;
 }
 
 static inline int
 usb_phy_notify_connect(struct usb_phy *x, enum usb_device_speed speed)
 {
-	if (x->notify_connect)
+	if (!IS_ERR(x) && x->notify_connect)
 		return x->notify_connect(x, speed);
-	else
-		return 0;
+
+	return 0;
 }
 
 static inline int
 usb_phy_notify_disconnect(struct usb_phy *x, enum usb_device_speed speed)
 {
-	if (x->notify_disconnect)
+	if (!IS_ERR(x) && x->notify_disconnect)
 		return x->notify_disconnect(x, speed);
-	else
-		return 0;
+
+	return 0;
 }
 
 /* notifiers */