i3c: master: add enable(disable) hot join in sys entry

Add hotjoin entry in sys file system allow user enable/disable hotjoin
feature.

Add (*enable(disable)_hotjoin)() to i3c_master_controller_ops.
Add api i3c_master_enable(disable)_hotjoin();

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20231201222532.2431484-2-Frank.Li@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 8b729ebae2a6ecf645ab34743121b4c7a575be6c..3afa530c5e3220fa96c7af96a4c90f7c673393f4 100644 (file)
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -557,6 +557,88 @@ static ssize_t i2c_scl_frequency_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(i2c_scl_frequency);
 
+static int i3c_set_hotjoin(struct i3c_master_controller *master, bool enable)
+{
+       int ret;
+
+       if (!master || !master->ops)
+               return -EINVAL;
+
+       if (!master->ops->enable_hotjoin || !master->ops->disable_hotjoin)
+               return -EINVAL;
+
+       i3c_bus_normaluse_lock(&master->bus);
+
+       if (enable)
+               ret = master->ops->enable_hotjoin(master);
+       else
+               ret = master->ops->disable_hotjoin(master);
+
+       master->hotjoin = enable;
+
+       i3c_bus_normaluse_unlock(&master->bus);
+
+       return ret;
+}
+
+static ssize_t hotjoin_store(struct device *dev, struct device_attribute *attr,
+                            const char *buf, size_t count)
+{
+       struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
+       int ret;
+       bool res;
+
+       if (!i3cbus->cur_master)
+               return -EINVAL;
+
+       if (kstrtobool(buf, &res))
+               return -EINVAL;
+
+       ret = i3c_set_hotjoin(i3cbus->cur_master->common.master, res);
+       if (ret)
+               return ret;
+
+       return count;
+}
+
+/*
+ * i3c_master_enable_hotjoin - Enable hotjoin
+ * @master: I3C master object
+ *
+ * Return: a 0 in case of success, an negative error code otherwise.
+ */
+int i3c_master_enable_hotjoin(struct i3c_master_controller *master)
+{
+       return i3c_set_hotjoin(master, true);
+}
+EXPORT_SYMBOL_GPL(i3c_master_enable_hotjoin);
+
+/*
+ * i3c_master_disable_hotjoin - Disable hotjoin
+ * @master: I3C master object
+ *
+ * Return: a 0 in case of success, an negative error code otherwise.
+ */
+int i3c_master_disable_hotjoin(struct i3c_master_controller *master)
+{
+       return i3c_set_hotjoin(master, false);
+}
+EXPORT_SYMBOL_GPL(i3c_master_disable_hotjoin);
+
+static ssize_t hotjoin_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+       struct i3c_bus *i3cbus = dev_to_i3cbus(dev);
+       ssize_t ret;
+
+       i3c_bus_normaluse_lock(i3cbus);
+       ret = sysfs_emit(buf, "%d\n", i3cbus->cur_master->common.master->hotjoin);
+       i3c_bus_normaluse_unlock(i3cbus);
+
+       return ret;
+}
+
+static DEVICE_ATTR_RW(hotjoin);
+
 static struct attribute *i3c_masterdev_attrs[] = {
        &dev_attr_mode.attr,
        &dev_attr_current_master.attr,
@@ -567,6 +649,7 @@ static struct attribute *i3c_masterdev_attrs[] = {
        &dev_attr_pid.attr,
        &dev_attr_dynamic_address.attr,
        &dev_attr_hdrcap.attr,
+       &dev_attr_hotjoin.attr,
        NULL,
 };
 ATTRIBUTE_GROUPS(i3c_masterdev);

diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index 24c1863b86e2b6940d263555515039fa0b317203..3b5bd8e3257c173cbc4e1a93f45ef2e4cbb6d440 100644 (file)
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -460,6 +460,8 @@ struct i3c_master_controller_ops {
        int (*disable_ibi)(struct i3c_dev_desc *dev);
        void (*recycle_ibi_slot)(struct i3c_dev_desc *dev,
                                 struct i3c_ibi_slot *slot);
+       int (*enable_hotjoin)(struct i3c_master_controller *master);
+       int (*disable_hotjoin)(struct i3c_master_controller *master);
 };
 
 /**
@@ -495,6 +497,7 @@ struct i3c_master_controller {
        const struct i3c_master_controller_ops *ops;
        unsigned int secondary : 1;
        unsigned int init_done : 1;
+       unsigned int hotjoin: 1;
        struct {
                struct list_head i3c;
                struct list_head i2c;
@@ -551,6 +554,8 @@ int i3c_master_register(struct i3c_master_controller *master,
                        const struct i3c_master_controller_ops *ops,
                        bool secondary);
 void i3c_master_unregister(struct i3c_master_controller *master);
+int i3c_master_enable_hotjoin(struct i3c_master_controller *master);
+int i3c_master_disable_hotjoin(struct i3c_master_controller *master);
 
 /**
  * i3c_dev_get_master_data() - get master private data attached to an I3C