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Date:   Wed,  7 Dec 2022 15:50:59 -0500
Mime-Version: 1.0
Message-ID: <20221207205059.3848851-1-zenghuchen@google.com>
Subject: [PATCH] I3C: export SETDASA method
From:   Jack Chen <zenghuchen@google.com>
To:     Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org,
        Jesus Sanchez-Palencia <jesussanp@google.com>,
        Mark Slevinsky <markslevinsky@google.com>,
        Jack Chen <zenghuchen@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Because not all I3C drivers have the hot-join feature ready, and
especially not all I3C devices support hot-join feature, exporting
SETDASA method could be useful. With this function, the I3C controller
could perform a DAA to I3C devices when users decide to turn these I3C
devices off and on again during run-time.

Tested: This change has been tested with turnning off an I3C device and
turning on it again during run-time. The device driver calls SETDASA
method to perform DAA to the device. And communication between I3C
controller and device is set up again correctly.

Signed-off-by: Jack Chen <zenghuchen@google.com>
---
 drivers/i3c/device.c       | 20 ++++++++++++++++++++
 drivers/i3c/internals.h    |  1 +
 drivers/i3c/master.c       | 19 +++++++++++++++++++
 include/linux/i3c/device.h |  2 ++
 4 files changed, 42 insertions(+)

diff --git a/drivers/i3c/device.c b/drivers/i3c/device.c
index e92d3e9a52bd..9762630b917e 100644
--- a/drivers/i3c/device.c
+++ b/drivers/i3c/device.c
@@ -50,6 +50,26 @@ int i3c_device_do_priv_xfers(struct i3c_device *dev,
 }
 EXPORT_SYMBOL_GPL(i3c_device_do_priv_xfers);
 
+/**
+ * i3c_device_do_setdasa() - do I3C dynamic address assignement with
+ *                           static address
+ *
+ * @dev: device with which the DAA should be done
+ *
+ * Return: 0 in case of success, a negative error core otherwise.
+ */
+int i3c_device_do_setdasa(struct i3c_device *dev)
+{
+	int ret;
+
+	i3c_bus_normaluse_lock(dev->bus);
+	ret = i3c_dev_setdasa_locked(dev->desc);
+	i3c_bus_normaluse_unlock(dev->bus);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(i3c_device_do_setdasa);
+
 /**
  * i3c_device_get_info() - get I3C device information
  *
diff --git a/drivers/i3c/internals.h b/drivers/i3c/internals.h
index 86b7b44cfca2..908a807badaf 100644
--- a/drivers/i3c/internals.h
+++ b/drivers/i3c/internals.h
@@ -15,6 +15,7 @@ extern struct bus_type i3c_bus_type;
 void i3c_bus_normaluse_lock(struct i3c_bus *bus);
 void i3c_bus_normaluse_unlock(struct i3c_bus *bus);
 
+int i3c_dev_setdasa_locked(struct i3c_dev_desc *dev);
 int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev,
 				 struct i3c_priv_xfer *xfers,
 				 int nxfers);
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 351c81a929a6..d7e6f6c99aea 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -2708,6 +2708,25 @@ int i3c_master_unregister(struct i3c_master_controller *master)
 }
 EXPORT_SYMBOL_GPL(i3c_master_unregister);
 
+int i3c_dev_setdasa_locked(struct i3c_dev_desc *dev)
+{
+	struct i3c_master_controller *master;
+
+	if (!dev)
+		return -ENOENT;
+
+	master = i3c_dev_get_master(dev);
+	if (!master)
+		return -EINVAL;
+
+	if (!dev->boardinfo || !dev->boardinfo->init_dyn_addr ||
+		!dev->boardinfo->static_addr)
+		return -EINVAL;
+
+	return i3c_master_setdasa_locked(master, dev->info.static_addr,
+						dev->boardinfo->init_dyn_addr);
+}
+
 int i3c_dev_do_priv_xfers_locked(struct i3c_dev_desc *dev,
 				 struct i3c_priv_xfer *xfers,
 				 int nxfers)
diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
index 8242e13e7b0b..90b6e0f7d29f 100644
--- a/include/linux/i3c/device.h
+++ b/include/linux/i3c/device.h
@@ -293,6 +293,8 @@ int i3c_device_do_priv_xfers(struct i3c_device *dev,
 			     struct i3c_priv_xfer *xfers,
 			     int nxfers);
 
+int i3c_device_do_setdasa(struct i3c_device *dev);
+
 void i3c_device_get_info(struct i3c_device *dev, struct i3c_device_info *info);
 
 struct i3c_ibi_payload {
-- 
2.39.0.rc0.267.gcb52ba06e7-goog