Re: [Intel-gfx] [PATCH v2 1/5] media: cec-notifier: Get notifier by device and connector name

[Neil Armstrong]

Hi Sean,

On 18/05/2018 17:48, Sean Paul wrote:
> On Fri, May 18, 2018 at 03:05:00PM +0200, Neil Armstrong wrote:
>> In non device-tree world, we can need to get the notifier by the driver
>> name directly and eventually defer probe if not yet created.
>>
>> This patch adds a variant of the get function by using the device name
>> instead and will not create a notifier if not yet created.
>>
>> But the i915 driver exposes at least 2 HDMI connectors, this patch also
>> adds the possibility to add a connector name tied to the notifier device
>> to form a tuple and associate different CEC controllers for each HDMI
>> connectors.
>>
>> Signed-off-by: Neil Armstrong 
> 
> Hi Neil,
> Thanks for posting these!
> 
>> ---
>>  drivers/media/cec/cec-notifier.c | 11 ---
>>  include/media/cec-notifier.h | 27 ---
>>  2 files changed, 32 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/media/cec/cec-notifier.c 
>> b/drivers/media/cec/cec-notifier.c
>> index 16dffa0..dd2078b 100644
>> --- a/drivers/media/cec/cec-notifier.c
>> +++ b/drivers/media/cec/cec-notifier.c
>> @@ -21,6 +21,7 @@ struct cec_notifier {
>>  struct list_head head;
>>  struct kref kref;
>>  struct device *dev;
>> +const char *conn;
>>  struct cec_adapter *cec_adap;
>>  void (*callback)(struct cec_adapter *adap, u16 pa);
>>  
>> @@ -30,13 +31,14 @@ struct cec_notifier {
>>  static LIST_HEAD(cec_notifiers);
>>  static DEFINE_MUTEX(cec_notifiers_lock);
>>  
>> -struct cec_notifier *cec_notifier_get(struct device *dev)
>> +struct cec_notifier *cec_notifier_get_conn(struct device *dev, const char 
>> *conn)
>>  {
>>  struct cec_notifier *n;
>>  
>>  mutex_lock(_notifiers_lock);
>>  list_for_each_entry(n, _notifiers, head) {
>> -if (n->dev == dev) {
>> +if (n->dev == dev &&
>> +(!conn || !strcmp(n->conn, conn))) {
>>  kref_get(>kref);
>>  mutex_unlock(_notifiers_lock);
>>  return n;
>> @@ -46,6 +48,8 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>>  if (!n)
>>  goto unlock;
>>  n->dev = dev;
>> +if (conn)
>> +n->conn = kstrdup(conn, GFP_KERNEL);
>>  n->phys_addr = CEC_PHYS_ADDR_INVALID;
>>  mutex_init(>lock);
>>  kref_init(>kref);
>> @@ -54,7 +58,7 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>>  mutex_unlock(_notifiers_lock);
>>  return n;
>>  }
>> -EXPORT_SYMBOL_GPL(cec_notifier_get);
>> +EXPORT_SYMBOL_GPL(cec_notifier_get_conn);
>>  
>>  static void cec_notifier_release(struct kref *kref)
>>  {
>> @@ -62,6 +66,7 @@ static void cec_notifier_release(struct kref *kref)
>>  container_of(kref, struct cec_notifier, kref);
>>  
>>  list_del(>head);
>> +kfree(n->conn);
>>  kfree(n);
>>  }
>>  
>> diff --git a/include/media/cec-notifier.h b/include/media/cec-notifier.h
>> index cf0add7..814eeef 100644
>> --- a/include/media/cec-notifier.h
>> +++ b/include/media/cec-notifier.h
>> @@ -20,8 +20,10 @@ struct cec_notifier;
>>  #if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
>>  
>>  /**
>> - * cec_notifier_get - find or create a new cec_notifier for the given 
>> device.
>> + * cec_notifier_get_conn - find or create a new cec_notifier for the given
>> + * device and connector tuple.
>>   * @dev: device that sends the events.
>> + * @conn: the connector name from which the event occurs
> 
> Probably best to use "name" instead of connector, since it doesn't necessarily
> _have_ to be a connector name. So, cec_notifier_get_by_name(dev, name)

I don't have a stong opinion, but since the CEC is tied to a connector, it 
should
mention connector, maybe conn_name ?

> 
>>   *
>>   * If a notifier for device @dev already exists, then increase the refcount
>>   * and return that notifier.
>> @@ -31,7 +33,8 @@ struct cec_notifier;
>>   *
>>   * Return NULL if the memory could not be allocated.
>>   */
>> -struct cec_notifier *cec_notifier_get(struct device *dev);
>> +struct cec_notifier *cec_notifier_get_conn(struct device *dev,
>> +   const char *conn);
>>  
>>  /**
>>   * cec_notifier_put - decrease refcount and delete when the refcount 
>> reaches 0.
>> @@ -85,7 +88,8 @@ void cec_register_cec_notifier(struct cec_adapter *adap,
>> struct cec_notifier *notifier);
>>  
>>  #else
>> -static inline struct cec_notifier *cec_notifier_get(struct device *dev)
>> +static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
>> + const char *conn)
>>  {
>>  /* A non-NULL pointer is expected on success */
>>  return (struct cec_notifier *)0xdeadfeed;
>> @@ -121,6 +125,23 @@ static inline void cec_register_cec_notifier(struct 
>> cec_adapter *adap,
>>  #endif
>>  
>>  /**
>> + * cec_notifier_get - find or create a new 

Re: [Intel-gfx] [PATCH v2 1/5] media: cec-notifier: Get notifier by device and connector name

[Sean Paul]

On Fri, May 18, 2018 at 03:05:00PM +0200, Neil Armstrong wrote:
> In non device-tree world, we can need to get the notifier by the driver
> name directly and eventually defer probe if not yet created.
> 
> This patch adds a variant of the get function by using the device name
> instead and will not create a notifier if not yet created.
> 
> But the i915 driver exposes at least 2 HDMI connectors, this patch also
> adds the possibility to add a connector name tied to the notifier device
> to form a tuple and associate different CEC controllers for each HDMI
> connectors.
> 
> Signed-off-by: Neil Armstrong 

Hi Neil,
Thanks for posting these!

> ---
>  drivers/media/cec/cec-notifier.c | 11 ---
>  include/media/cec-notifier.h | 27 ---
>  2 files changed, 32 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/cec/cec-notifier.c 
> b/drivers/media/cec/cec-notifier.c
> index 16dffa0..dd2078b 100644
> --- a/drivers/media/cec/cec-notifier.c
> +++ b/drivers/media/cec/cec-notifier.c
> @@ -21,6 +21,7 @@ struct cec_notifier {
>   struct list_head head;
>   struct kref kref;
>   struct device *dev;
> + const char *conn;
>   struct cec_adapter *cec_adap;
>   void (*callback)(struct cec_adapter *adap, u16 pa);
>  
> @@ -30,13 +31,14 @@ struct cec_notifier {
>  static LIST_HEAD(cec_notifiers);
>  static DEFINE_MUTEX(cec_notifiers_lock);
>  
> -struct cec_notifier *cec_notifier_get(struct device *dev)
> +struct cec_notifier *cec_notifier_get_conn(struct device *dev, const char 
> *conn)
>  {
>   struct cec_notifier *n;
>  
>   mutex_lock(_notifiers_lock);
>   list_for_each_entry(n, _notifiers, head) {
> - if (n->dev == dev) {
> + if (n->dev == dev &&
> + (!conn || !strcmp(n->conn, conn))) {
>   kref_get(>kref);
>   mutex_unlock(_notifiers_lock);
>   return n;
> @@ -46,6 +48,8 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>   if (!n)
>   goto unlock;
>   n->dev = dev;
> + if (conn)
> + n->conn = kstrdup(conn, GFP_KERNEL);
>   n->phys_addr = CEC_PHYS_ADDR_INVALID;
>   mutex_init(>lock);
>   kref_init(>kref);
> @@ -54,7 +58,7 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>   mutex_unlock(_notifiers_lock);
>   return n;
>  }
> -EXPORT_SYMBOL_GPL(cec_notifier_get);
> +EXPORT_SYMBOL_GPL(cec_notifier_get_conn);
>  
>  static void cec_notifier_release(struct kref *kref)
>  {
> @@ -62,6 +66,7 @@ static void cec_notifier_release(struct kref *kref)
>   container_of(kref, struct cec_notifier, kref);
>  
>   list_del(>head);
> + kfree(n->conn);
>   kfree(n);
>  }
>  
> diff --git a/include/media/cec-notifier.h b/include/media/cec-notifier.h
> index cf0add7..814eeef 100644
> --- a/include/media/cec-notifier.h
> +++ b/include/media/cec-notifier.h
> @@ -20,8 +20,10 @@ struct cec_notifier;
>  #if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
>  
>  /**
> - * cec_notifier_get - find or create a new cec_notifier for the given device.
> + * cec_notifier_get_conn - find or create a new cec_notifier for the given
> + * device and connector tuple.
>   * @dev: device that sends the events.
> + * @conn: the connector name from which the event occurs

Probably best to use "name" instead of connector, since it doesn't necessarily
_have_ to be a connector name. So, cec_notifier_get_by_name(dev, name)

>   *
>   * If a notifier for device @dev already exists, then increase the refcount
>   * and return that notifier.
> @@ -31,7 +33,8 @@ struct cec_notifier;
>   *
>   * Return NULL if the memory could not be allocated.
>   */
> -struct cec_notifier *cec_notifier_get(struct device *dev);
> +struct cec_notifier *cec_notifier_get_conn(struct device *dev,
> +const char *conn);
>  
>  /**
>   * cec_notifier_put - decrease refcount and delete when the refcount reaches 
> 0.
> @@ -85,7 +88,8 @@ void cec_register_cec_notifier(struct cec_adapter *adap,
>  struct cec_notifier *notifier);
>  
>  #else
> -static inline struct cec_notifier *cec_notifier_get(struct device *dev)
> +static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
> +  const char *conn)
>  {
>   /* A non-NULL pointer is expected on success */
>   return (struct cec_notifier *)0xdeadfeed;
> @@ -121,6 +125,23 @@ static inline void cec_register_cec_notifier(struct 
> cec_adapter *adap,
>  #endif
>  
>  /**
> + * cec_notifier_get - find or create a new cec_notifier for the given device.
> + * @dev: device that sends the events.
> + *
> + * If a notifier for device @dev already exists, then increase the refcount
> + * and return that notifier.
> + *
> + * If it doesn't exist, then allocate a new notifier struct and return a

Re: [Intel-gfx] [PATCH v2 1/5] media: cec-notifier: Get notifier by device and connector name

[Neil Armstrong]

On 15/05/2018 17:22, Hans Verkuil wrote:
> On 05/15/2018 04:42 PM, Neil Armstrong wrote:
>> In non device-tree world, we can need to get the notifier by the driver
>> name directly and eventually defer probe if not yet created.
>>
>> This patch adds a variant of the get function by using the device name
>> instead and will not create a notifier if not yet created.
>>
>> But the i915 driver exposes at least 2 HDMI connectors, this patch also
>> adds the possibility to add a connector name tied to the notifier device
>> to form a tuple and associate different CEC controllers for each HDMI
>> connectors.
> 
> The patch looks good, but I'm curious about this paragraph above.
> 
> Was this tested with devices with more than one HDMI output? Or only on
> laptops with a single physical HDMI output? If there are two or more
> outputs then I guess it is the HW designer that decides with output gets
> CEC support?

The driver exposes 2 HDMI connectors (I suspect one is connected to the USB-C 
alt mode mux along the DP port),
and only one connected has the CEC line connected to the Embedded Controller.

Neil

> 
> Regards,
> 
>   Hans
> 
>>
>> Signed-off-by: Neil Armstrong 
>> ---
>>  drivers/media/cec/cec-notifier.c | 11 ---
>>  include/media/cec-notifier.h | 27 ---
>>  2 files changed, 32 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/media/cec/cec-notifier.c 
>> b/drivers/media/cec/cec-notifier.c
>> index 16dffa0..dd2078b 100644
>> --- a/drivers/media/cec/cec-notifier.c
>> +++ b/drivers/media/cec/cec-notifier.c
>> @@ -21,6 +21,7 @@ struct cec_notifier {
>>  struct list_head head;
>>  struct kref kref;
>>  struct device *dev;
>> +const char *conn;
>>  struct cec_adapter *cec_adap;
>>  void (*callback)(struct cec_adapter *adap, u16 pa);
>>  
>> @@ -30,13 +31,14 @@ struct cec_notifier {
>>  static LIST_HEAD(cec_notifiers);
>>  static DEFINE_MUTEX(cec_notifiers_lock);
>>  
>> -struct cec_notifier *cec_notifier_get(struct device *dev)
>> +struct cec_notifier *cec_notifier_get_conn(struct device *dev, const char 
>> *conn)
>>  {
>>  struct cec_notifier *n;
>>  
>>  mutex_lock(_notifiers_lock);
>>  list_for_each_entry(n, _notifiers, head) {
>> -if (n->dev == dev) {
>> +if (n->dev == dev &&
>> +(!conn || !strcmp(n->conn, conn))) {
>>  kref_get(>kref);
>>  mutex_unlock(_notifiers_lock);
>>  return n;
>> @@ -46,6 +48,8 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>>  if (!n)
>>  goto unlock;
>>  n->dev = dev;
>> +if (conn)
>> +n->conn = kstrdup(conn, GFP_KERNEL);
>>  n->phys_addr = CEC_PHYS_ADDR_INVALID;
>>  mutex_init(>lock);
>>  kref_init(>kref);
>> @@ -54,7 +58,7 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>>  mutex_unlock(_notifiers_lock);
>>  return n;
>>  }
>> -EXPORT_SYMBOL_GPL(cec_notifier_get);
>> +EXPORT_SYMBOL_GPL(cec_notifier_get_conn);
>>  
>>  static void cec_notifier_release(struct kref *kref)
>>  {
>> @@ -62,6 +66,7 @@ static void cec_notifier_release(struct kref *kref)
>>  container_of(kref, struct cec_notifier, kref);
>>  
>>  list_del(>head);
>> +kfree(n->conn);
>>  kfree(n);
>>  }
>>  
>> diff --git a/include/media/cec-notifier.h b/include/media/cec-notifier.h
>> index cf0add7..814eeef 100644
>> --- a/include/media/cec-notifier.h
>> +++ b/include/media/cec-notifier.h
>> @@ -20,8 +20,10 @@ struct cec_notifier;
>>  #if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
>>  
>>  /**
>> - * cec_notifier_get - find or create a new cec_notifier for the given 
>> device.
>> + * cec_notifier_get_conn - find or create a new cec_notifier for the given
>> + * device and connector tuple.
>>   * @dev: device that sends the events.
>> + * @conn: the connector name from which the event occurs
>>   *
>>   * If a notifier for device @dev already exists, then increase the refcount
>>   * and return that notifier.
>> @@ -31,7 +33,8 @@ struct cec_notifier;
>>   *
>>   * Return NULL if the memory could not be allocated.
>>   */
>> -struct cec_notifier *cec_notifier_get(struct device *dev);
>> +struct cec_notifier *cec_notifier_get_conn(struct device *dev,
>> +   const char *conn);
>>  
>>  /**
>>   * cec_notifier_put - decrease refcount and delete when the refcount 
>> reaches 0.
>> @@ -85,7 +88,8 @@ void cec_register_cec_notifier(struct cec_adapter *adap,
>> struct cec_notifier *notifier);
>>  
>>  #else
>> -static inline struct cec_notifier *cec_notifier_get(struct device *dev)
>> +static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
>> + const char *conn)
>>  {
>>  /* A non-NULL pointer is expected on success */
>>  return (struct cec_notifier 

Re: [Intel-gfx] [PATCH v2 1/5] media: cec-notifier: Get notifier by device and connector name

[Hans Verkuil]

On 05/15/2018 04:42 PM, Neil Armstrong wrote:
> In non device-tree world, we can need to get the notifier by the driver
> name directly and eventually defer probe if not yet created.
> 
> This patch adds a variant of the get function by using the device name
> instead and will not create a notifier if not yet created.
> 
> But the i915 driver exposes at least 2 HDMI connectors, this patch also
> adds the possibility to add a connector name tied to the notifier device
> to form a tuple and associate different CEC controllers for each HDMI
> connectors.

The patch looks good, but I'm curious about this paragraph above.

Was this tested with devices with more than one HDMI output? Or only on
laptops with a single physical HDMI output? If there are two or more
outputs then I guess it is the HW designer that decides with output gets
CEC support?

Regards,

Hans

> 
> Signed-off-by: Neil Armstrong 
> ---
>  drivers/media/cec/cec-notifier.c | 11 ---
>  include/media/cec-notifier.h | 27 ---
>  2 files changed, 32 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/media/cec/cec-notifier.c 
> b/drivers/media/cec/cec-notifier.c
> index 16dffa0..dd2078b 100644
> --- a/drivers/media/cec/cec-notifier.c
> +++ b/drivers/media/cec/cec-notifier.c
> @@ -21,6 +21,7 @@ struct cec_notifier {
>   struct list_head head;
>   struct kref kref;
>   struct device *dev;
> + const char *conn;
>   struct cec_adapter *cec_adap;
>   void (*callback)(struct cec_adapter *adap, u16 pa);
>  
> @@ -30,13 +31,14 @@ struct cec_notifier {
>  static LIST_HEAD(cec_notifiers);
>  static DEFINE_MUTEX(cec_notifiers_lock);
>  
> -struct cec_notifier *cec_notifier_get(struct device *dev)
> +struct cec_notifier *cec_notifier_get_conn(struct device *dev, const char 
> *conn)
>  {
>   struct cec_notifier *n;
>  
>   mutex_lock(_notifiers_lock);
>   list_for_each_entry(n, _notifiers, head) {
> - if (n->dev == dev) {
> + if (n->dev == dev &&
> + (!conn || !strcmp(n->conn, conn))) {
>   kref_get(>kref);
>   mutex_unlock(_notifiers_lock);
>   return n;
> @@ -46,6 +48,8 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>   if (!n)
>   goto unlock;
>   n->dev = dev;
> + if (conn)
> + n->conn = kstrdup(conn, GFP_KERNEL);
>   n->phys_addr = CEC_PHYS_ADDR_INVALID;
>   mutex_init(>lock);
>   kref_init(>kref);
> @@ -54,7 +58,7 @@ struct cec_notifier *cec_notifier_get(struct device *dev)
>   mutex_unlock(_notifiers_lock);
>   return n;
>  }
> -EXPORT_SYMBOL_GPL(cec_notifier_get);
> +EXPORT_SYMBOL_GPL(cec_notifier_get_conn);
>  
>  static void cec_notifier_release(struct kref *kref)
>  {
> @@ -62,6 +66,7 @@ static void cec_notifier_release(struct kref *kref)
>   container_of(kref, struct cec_notifier, kref);
>  
>   list_del(>head);
> + kfree(n->conn);
>   kfree(n);
>  }
>  
> diff --git a/include/media/cec-notifier.h b/include/media/cec-notifier.h
> index cf0add7..814eeef 100644
> --- a/include/media/cec-notifier.h
> +++ b/include/media/cec-notifier.h
> @@ -20,8 +20,10 @@ struct cec_notifier;
>  #if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
>  
>  /**
> - * cec_notifier_get - find or create a new cec_notifier for the given device.
> + * cec_notifier_get_conn - find or create a new cec_notifier for the given
> + * device and connector tuple.
>   * @dev: device that sends the events.
> + * @conn: the connector name from which the event occurs
>   *
>   * If a notifier for device @dev already exists, then increase the refcount
>   * and return that notifier.
> @@ -31,7 +33,8 @@ struct cec_notifier;
>   *
>   * Return NULL if the memory could not be allocated.
>   */
> -struct cec_notifier *cec_notifier_get(struct device *dev);
> +struct cec_notifier *cec_notifier_get_conn(struct device *dev,
> +const char *conn);
>  
>  /**
>   * cec_notifier_put - decrease refcount and delete when the refcount reaches 
> 0.
> @@ -85,7 +88,8 @@ void cec_register_cec_notifier(struct cec_adapter *adap,
>  struct cec_notifier *notifier);
>  
>  #else
> -static inline struct cec_notifier *cec_notifier_get(struct device *dev)
> +static inline struct cec_notifier *cec_notifier_get_conn(struct device *dev,
> +  const char *conn)
>  {
>   /* A non-NULL pointer is expected on success */
>   return (struct cec_notifier *)0xdeadfeed;
> @@ -121,6 +125,23 @@ static inline void cec_register_cec_notifier(struct 
> cec_adapter *adap,
>  #endif
>  
>  /**
> + * cec_notifier_get - find or create a new cec_notifier for the given device.
> + * @dev: device that sends the events.
> + *
> + * If a notifier for device @dev already exists, then increase the refcount