diff mbox series

[net-next,v2,2/3] i3c: Add support for bus enumeration & notification

Message ID 20230717040638.1292536-3-matt@codeconstruct.com.au (mailing list archive)
State Superseded
Headers show
Series I3C MCTP net driver | expand

Commit Message

Matt Johnston July 17, 2023, 4:06 a.m. UTC 
From: Jeremy Kerr <jk@codeconstruct.com.au>

This allows other drivers to be notified when new i3c busses are
attached, referring to a whole i3c bus as opposed to individual
devices.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
 drivers/i3c/master.c       | 35 +++++++++++++++++++++++++++++++++++
 include/linux/i3c/master.h | 11 +++++++++++
 2 files changed, 46 insertions(+)

Comments

Jakub Kicinski July 19, 2023, 1:57 a.m. UTC | #1 
On Mon, 17 Jul 2023 12:06:37 +0800 Matt Johnston wrote:
> From: Jeremy Kerr <jk@codeconstruct.com.au>
> 
> This allows other drivers to be notified when new i3c busses are
> attached, referring to a whole i3c bus as opposed to individual
> devices.
> 
> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
> Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>

We need one of:
 - sign-off from Alexandre that he's okay with this code going via
   netdev; or
 - stable branch from Alexandre based on an upstream -rc tag which 
   we can pull into net-next; or
 - wait until 6.6 merge window for the change to propagate.
Until then we can't do much on our end, so I'll mark the patches as
deferred from netdev perspective.
Alexandre Belloni July 19, 2023, 9:10 a.m. UTC | #2 
On 17/07/2023 12:06:37+0800, Matt Johnston wrote:
> From: Jeremy Kerr <jk@codeconstruct.com.au>
> 
> This allows other drivers to be notified when new i3c busses are
> attached, referring to a whole i3c bus as opposed to individual
> devices.
> 
> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
> Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>

Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

> ---
>  drivers/i3c/master.c       | 35 +++++++++++++++++++++++++++++++++++
>  include/linux/i3c/master.h | 11 +++++++++++
>  2 files changed, 46 insertions(+)
> 
> diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> index 08aeb69a7800..2276abe38bdc 100644
> --- a/drivers/i3c/master.c
> +++ b/drivers/i3c/master.c
> @@ -22,6 +22,7 @@
>  static DEFINE_IDR(i3c_bus_idr);
>  static DEFINE_MUTEX(i3c_core_lock);
>  static int __i3c_first_dynamic_bus_num;
> +static BLOCKING_NOTIFIER_HEAD(i3c_bus_notifier);
>  
>  /**
>   * i3c_bus_maintenance_lock - Lock the bus for a maintenance operation
> @@ -453,6 +454,36 @@ static int i3c_bus_init(struct i3c_bus *i3cbus, struct device_node *np)
>  	return 0;
>  }
>  
> +void i3c_for_each_bus_locked(int (*fn)(struct i3c_bus *bus, void *data),
> +			     void *data)
> +{
> +	struct i3c_bus *bus;
> +	int id;
> +
> +	mutex_lock(&i3c_core_lock);
> +	idr_for_each_entry(&i3c_bus_idr, bus, id)
> +		fn(bus, data);
> +	mutex_unlock(&i3c_core_lock);
> +}
> +EXPORT_SYMBOL_GPL(i3c_for_each_bus_locked);
> +
> +int i3c_register_notifier(struct notifier_block *nb)
> +{
> +	return blocking_notifier_chain_register(&i3c_bus_notifier, nb);
> +}
> +EXPORT_SYMBOL_GPL(i3c_register_notifier);
> +
> +int i3c_unregister_notifier(struct notifier_block *nb)
> +{
> +	return blocking_notifier_chain_unregister(&i3c_bus_notifier, nb);
> +}
> +EXPORT_SYMBOL_GPL(i3c_unregister_notifier);
> +
> +static void i3c_bus_notify(struct i3c_bus *bus, unsigned int action)
> +{
> +	blocking_notifier_call_chain(&i3c_bus_notifier, action, bus);
> +}
> +
>  static const char * const i3c_bus_mode_strings[] = {
>  	[I3C_BUS_MODE_PURE] = "pure",
>  	[I3C_BUS_MODE_MIXED_FAST] = "mixed-fast",
> @@ -2678,6 +2709,8 @@ int i3c_master_register(struct i3c_master_controller *master,
>  	if (ret)
>  		goto err_del_dev;
>  
> +	i3c_bus_notify(i3cbus, I3C_NOTIFY_BUS_ADD);
> +
>  	/*
>  	 * We're done initializing the bus and the controller, we can now
>  	 * register I3C devices discovered during the initial DAA.
> @@ -2710,6 +2743,8 @@ EXPORT_SYMBOL_GPL(i3c_master_register);
>   */
>  void i3c_master_unregister(struct i3c_master_controller *master)
>  {
> +	i3c_bus_notify(&master->bus, I3C_NOTIFY_BUS_REMOVE);
> +
>  	i3c_master_i2c_adapter_cleanup(master);
>  	i3c_master_unregister_i3c_devs(master);
>  	i3c_master_bus_cleanup(master);
> diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
> index 0b52da4f2346..db909ef79be4 100644
> --- a/include/linux/i3c/master.h
> +++ b/include/linux/i3c/master.h
> @@ -24,6 +24,12 @@
>  
>  struct i2c_client;
>  
> +/* notifier actions. notifier call data is the struct i3c_bus */
> +enum {
> +	I3C_NOTIFY_BUS_ADD,
> +	I3C_NOTIFY_BUS_REMOVE,
> +};
> +
>  struct i3c_master_controller;
>  struct i3c_bus;
>  struct i3c_device;
> @@ -652,4 +658,9 @@ void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot);
>  
>  struct i3c_ibi_slot *i3c_master_get_free_ibi_slot(struct i3c_dev_desc *dev);
>  
> +void i3c_for_each_bus_locked(int (*fn)(struct i3c_bus *bus, void *data),
> +			     void *data);
> +int i3c_register_notifier(struct notifier_block *nb);
> +int i3c_unregister_notifier(struct notifier_block *nb);
> +
>  #endif /* I3C_MASTER_H */
> -- 
> 2.37.2
>
Alexandre Belloni July 19, 2023, 9:11 a.m. UTC | #3 
On 18/07/2023 18:57:57-0700, Jakub Kicinski wrote:
> On Mon, 17 Jul 2023 12:06:37 +0800 Matt Johnston wrote:
> > From: Jeremy Kerr <jk@codeconstruct.com.au>
> > 
> > This allows other drivers to be notified when new i3c busses are
> > attached, referring to a whole i3c bus as opposed to individual
> > devices.
> > 
> > Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
> > Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
> 
> We need one of:
>  - sign-off from Alexandre that he's okay with this code going via
>    netdev; or
>  - stable branch from Alexandre based on an upstream -rc tag which 
>    we can pull into net-next; or
>  - wait until 6.6 merge window for the change to propagate.
> Until then we can't do much on our end, so I'll mark the patches as
> deferred from netdev perspective.

I'm fine with the series going through netdev. Matt, please carry my ack
on the next versions.

> -- 
> pw-bot: defer
diff mbox series

Patch

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 08aeb69a7800..2276abe38bdc 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -22,6 +22,7 @@ 
 static DEFINE_IDR(i3c_bus_idr);
 static DEFINE_MUTEX(i3c_core_lock);
 static int __i3c_first_dynamic_bus_num;
+static BLOCKING_NOTIFIER_HEAD(i3c_bus_notifier);
 
 /**
  * i3c_bus_maintenance_lock - Lock the bus for a maintenance operation
@@ -453,6 +454,36 @@  static int i3c_bus_init(struct i3c_bus *i3cbus, struct device_node *np)
 	return 0;
 }
 
+void i3c_for_each_bus_locked(int (*fn)(struct i3c_bus *bus, void *data),
+			     void *data)
+{
+	struct i3c_bus *bus;
+	int id;
+
+	mutex_lock(&i3c_core_lock);
+	idr_for_each_entry(&i3c_bus_idr, bus, id)
+		fn(bus, data);
+	mutex_unlock(&i3c_core_lock);
+}
+EXPORT_SYMBOL_GPL(i3c_for_each_bus_locked);
+
+int i3c_register_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&i3c_bus_notifier, nb);
+}
+EXPORT_SYMBOL_GPL(i3c_register_notifier);
+
+int i3c_unregister_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&i3c_bus_notifier, nb);
+}
+EXPORT_SYMBOL_GPL(i3c_unregister_notifier);
+
+static void i3c_bus_notify(struct i3c_bus *bus, unsigned int action)
+{
+	blocking_notifier_call_chain(&i3c_bus_notifier, action, bus);
+}
+
 static const char * const i3c_bus_mode_strings[] = {
 	[I3C_BUS_MODE_PURE] = "pure",
 	[I3C_BUS_MODE_MIXED_FAST] = "mixed-fast",
@@ -2678,6 +2709,8 @@  int i3c_master_register(struct i3c_master_controller *master,
 	if (ret)
 		goto err_del_dev;
 
+	i3c_bus_notify(i3cbus, I3C_NOTIFY_BUS_ADD);
+
 	/*
 	 * We're done initializing the bus and the controller, we can now
 	 * register I3C devices discovered during the initial DAA.
@@ -2710,6 +2743,8 @@  EXPORT_SYMBOL_GPL(i3c_master_register);
  */
 void i3c_master_unregister(struct i3c_master_controller *master)
 {
+	i3c_bus_notify(&master->bus, I3C_NOTIFY_BUS_REMOVE);
+
 	i3c_master_i2c_adapter_cleanup(master);
 	i3c_master_unregister_i3c_devs(master);
 	i3c_master_bus_cleanup(master);
diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index 0b52da4f2346..db909ef79be4 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -24,6 +24,12 @@ 
 
 struct i2c_client;
 
+/* notifier actions. notifier call data is the struct i3c_bus */
+enum {
+	I3C_NOTIFY_BUS_ADD,
+	I3C_NOTIFY_BUS_REMOVE,
+};
+
 struct i3c_master_controller;
 struct i3c_bus;
 struct i3c_device;
@@ -652,4 +658,9 @@  void i3c_master_queue_ibi(struct i3c_dev_desc *dev, struct i3c_ibi_slot *slot);
 
 struct i3c_ibi_slot *i3c_master_get_free_ibi_slot(struct i3c_dev_desc *dev);
 
+void i3c_for_each_bus_locked(int (*fn)(struct i3c_bus *bus, void *data),
+			     void *data);
+int i3c_register_notifier(struct notifier_block *nb);
+int i3c_unregister_notifier(struct notifier_block *nb);
+
 #endif /* I3C_MASTER_H */