[PATCH v4 1/6] i3c: master: add enable(disable) hot join in sys entry

Frank Li
2023-11-29T22:12:56Z

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>
---
drivers/i3c/master.c | 84 ++++++++++++++++++++++++++++++++++++++
include/linux/i3c/master.h | 5 +++
2 files changed, 89 insertions(+)

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 08aeb69a78003..ed5e27cd20811 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -526,6 +526,89 @@ 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 ||
+ !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;
+ long res;
+
+ if (!i3cbus->cur_master)
+ return -EINVAL;
+
+ if (kstrtol(buf, 10, &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,
@@ -536,6 +619,7 @@ 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 0b52da4f23467..65b8965968af2 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -452,6 +452,8 @@ 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);
};

/**
@@ -487,6 +489,7 @@ 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;
@@ -543,6 +546,8 @@ 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
--
2.34.1