[PATCH v10 5/7] i3c: master: add defslvs processing

From: Parshuram Thombare <pthombar@cadence.com>
To: <alexandre.belloni@bootlin.com>, <slongerbeam@gmail.com>,
	<vitor.soares@synopsys.com>
Cc: <linux-i3c@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
	<mparab@cadence.com>, <praneeth@ti.com>,
	Parshuram Thombare <pthombar@cadence.com>
Subject: [PATCH v10 5/7] i3c: master: add defslvs processing
Date: Mon, 30 Nov 2020 07:19:38 +0100	[thread overview]
Message-ID: <1606717178-4151-1-git-send-email-pthombar@cadence.com> (raw)
In-Reply-To: <1606716983-3645-1-git-send-email-pthombar@cadence.com>

Added defslvs processing code to the I3C master subsystem.

Signed-off-by: Parshuram Thombare <pthombar@cadence.com>
---
 drivers/i3c/master.c       |   68 ++++++++++++++++++++++++++++++++++++++++++-
 include/linux/i3c/master.h |    7 ++++
 2 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 51ef706..c01ba00 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -2172,7 +2172,7 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
 	else
 		expected_dyn_addr = newdev->info.dyn_addr;
 
-	if (newdev->info.dyn_addr != expected_dyn_addr) {
+	if (!master->secondary && newdev->info.dyn_addr != expected_dyn_addr) {
 		/*
 		 * Try to apply the expected dynamic address. If it fails, keep
 		 * the address assigned by the master.
@@ -2867,12 +2867,20 @@ int i3c_secondary_master_register(struct i3c_master_controller *master,
 				  struct device *parent,
 				  const struct i3c_master_controller_ops *ops)
 {
-	int ret;
+	int ret, sz;
 
 	ret = i3c_master_init(master, parent, ops, true);
 	if (ret)
 		return ret;
 
+	sz = sizeof(struct i3c_ccc_dev_desc) * I3C_BUS_MAX_DEVS;
+	master->defslvs_data.devs = devm_kzalloc(&master->dev, sz,
+						 GFP_KERNEL);
+	if (!master->defslvs_data.devs) {
+		ret = -ENOMEM;
+		goto err_cleanup_bus;
+	}
+
 	ret = device_add(&master->dev);
 	if (ret)
 		goto err_cleanup_bus;
@@ -2905,6 +2913,62 @@ int i3c_secondary_master_register(struct i3c_master_controller *master,
 }
 EXPORT_SYMBOL_GPL(i3c_secondary_master_register);
 
+static int
+i3c_master_populate_bus(struct i3c_master_controller *master, u8 dyn_addr)
+{
+	struct i3c_dev_desc *olddev;
+	struct i3c_ccc_dev_desc *desc;
+	int ret, slot;
+
+	i3c_bus_for_each_i3cdev(&master->bus, olddev)
+		i3c_master_put_i3c_addrs(olddev);
+
+	master->this->info.dyn_addr = dyn_addr;
+	i3c_master_get_i3c_addrs(master->this);
+
+	desc = master->defslvs_data.devs;
+	for (slot = 1; slot < master->defslvs_data.ndevs; slot++) {
+		ret = i3c_master_add_i3c_dev_locked(master,
+						    desc[slot].dyn_addr);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+/**
+ * i3c_master_process_defslvs() - process I3C device list received in
+ * DEFSLVS for device plug/unplug and address change.
+ * @m: I3C master object
+ * @dyn_addr: Current dynamic address of this device
+ *
+ * This function may sleep, so should not be called in the atomic context.
+ */
+int i3c_master_process_defslvs(struct i3c_master_controller *m, u8 dyn_addr)
+{
+	int ret;
+
+	i3c_bus_normaluse_lock(&m->bus);
+	ret = i3c_master_acquire_bus(m);
+	i3c_bus_normaluse_unlock(&m->bus);
+	if (ret)
+		return ret;
+
+	i3c_bus_maintenance_lock(&m->bus);
+	ret = i3c_master_populate_bus(m, dyn_addr);
+	i3c_bus_maintenance_unlock(&m->bus);
+	if (!ret) {
+		i3c_bus_normaluse_lock(&m->bus);
+		i3c_master_register_new_i3c_devs(m);
+		i3c_bus_normaluse_unlock(&m->bus);
+	}
+	i3c_master_enable_mr_events(m);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(i3c_master_process_defslvs);
+
 /**
  * i3c_master_unregister() - unregister an I3C master
  * @master: master used to send frames on the bus
diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index 77c0422..835f823 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -478,6 +478,8 @@ struct i3c_master_controller_ops {
  *	in a thread context. Typical examples are Hot Join processing which
  *	requires taking the bus lock in maintenance, which in turn, can only
  *	be done from a sleep-able context
+ * @defslvs_data: list used to pass i3c device list received in DEFSLVS message,
+ *	from DEFSLVS controller driver to I3C core
  *
  * A &struct i3c_master_controller has to be registered to the I3C subsystem
  * through i3c_master_register(). None of &struct i3c_master_controller fields
@@ -497,6 +499,10 @@ struct i3c_master_controller {
 	} boardinfo;
 	struct i3c_bus bus;
 	struct workqueue_struct *wq;
+	struct {
+		u32 ndevs;
+		struct i3c_ccc_dev_desc *devs;
+	} defslvs_data;
 };
 
 /**
@@ -523,6 +529,7 @@ struct i3c_master_controller {
 
 void i3c_master_yield_bus(struct i3c_master_controller *m,
 			  u8 sec_mst_dyn_addr);
+int i3c_master_process_defslvs(struct i3c_master_controller *m, u8 dyn_addr);
 int i3c_master_do_i2c_xfers(struct i3c_master_controller *master,
 			    const struct i2c_msg *xfers,
 			    int nxfers);
-- 
1.7.1

