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* [RESEND PATCH v9 0/7] I3C mastership handover support
@ 2020-11-29 14:19 Parshuram Thombare
  2020-11-29 14:20 ` [PATCH v9 1/7] i3c: master: master initialization flow document Parshuram Thombare
                   ` (7 more replies)
  0 siblings, 8 replies; 11+ messages in thread
From: Parshuram Thombare @ 2020-11-29 14:19 UTC (permalink / raw)
  To: alexandre.belloni, slongerbeam, vitor.soares
  Cc: praneeth, mparab, linux-i3c, linux-kernel, Parshuram Thombare

Main changes between v8 and v9 are:
- Fix NULL dereference issue in current_master_show when
  cat'ing sysfs key current_master for secondary master
  before primary master gets initialized.

Main changes between v7 and v8 are:
- Document format changed from table to DOT diagram
- Appropriate names for few functions
- Moved mastership request process entirely to the driver
- Reuse of i3c_master_add_i3c_dev_locked in core defslvs
  processing

Main changes between v6 and v7 are:
- Added separate functions for main and secondary
  master initialization
- Secondary master initialization don't wait for
  DEFSLSVS.
- Change to use I2C device information from DTS,
  and corresponding changes in controller driver
  and I3C core DEFSLVS processing to ignore I2C
  devices received in DEFSLVS
- Reverted bus_init split
- Fixed formatting issues in document

Main changes between v5 and v6 are:
- Moved populate_bus() hook to master subsystem code.
- For secondary master initialization i3c_master_register
  spawan separate threads, as secondary master may have to
  wait for DEFSLVS and bus mastership.
- Populate bus info is based on DEFSLVS data and take care
  of hot plugged / unplugged I3C devices.
- Split bus_init into bus_init and master_set_info callbacks
- Moved mastership aquire and handover to separate state 
  machines.
- Added DEFSLVS processing code.
- Moved back all locks in side the subsystem code.
- Secondary mastership support to Cadence I3C master
  controller driver
- Sysfs key 'i3c_acquire_bus' to acauire bus.
- NULL check for pool pointer in i3c_generic_ibi_free_pool.

Main changes between v4 and v5 are:
- Add populate_bus() hook
- Split i3c_master_register into init and register pair
- Split device information retrieval, let add partialy discovered devices
- Make i3c_master_set_info private
- Add separate function to register secondary master
- Reworked secondary master register in CDNS driver
- Export i3c_bus_set_mode

Main changes between v3 and v4 are:
- Reworked acquire bus ownership
- Refactored the code

Main changes between v2 and v3 are:
- Added DEFSLVS devices are registered from master driver
- Reworked I2C registering on secondary master side
- Reworked Mastership event is enabled/disabled globally (for all devices)

Main changes between initial version and v2 are:
- Reworked devices registration on secondary master side
- Reworked mastership event disabling/enabling
- Reworked bus locking during mastership takeover process
- Added DEFSLVS devices registration during initialization
- Fixed style issues

Parshuram Thombare (7):
  i3c: master: master initialization flow document
  i3c: master: use i3c_master_register only for main master
  i3c: master: add i3c_secondary_master_register
  i3c: master: add mastership handover support
  i3c: master: add defslvs processing
  i3c: master: sysfs key for acquire bus
  i3c: master: mastership handover, defslvs processing in cdns
    controller driver

 Documentation/driver-api/i3c/index.rst             |    1 +
 .../driver-api/i3c/master-initialization-flow.rst  |  187 ++++++++
 drivers/i3c/master.c                               |  497 ++++++++++++++++++--
 drivers/i3c/master/dw-i3c-master.c                 |    4 +-
 drivers/i3c/master/i3c-master-cdns.c               |  329 ++++++++++++-
 include/linux/i3c/master.h                         |   23 +-
 6 files changed, 968 insertions(+), 73 deletions(-)
 create mode 100644 Documentation/driver-api/i3c/master-initialization-flow.rst


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^ permalink raw reply	[flat|nested] 11+ messages in thread
* [PATCH v9 3/7] i3c: master: add i3c_secondary_master_register
@ 2020-11-28 14:46 Parshuram Thombare
  0 siblings, 0 replies; 11+ messages in thread
From: Parshuram Thombare @ 2020-11-28 14:46 UTC (permalink / raw)
  To: alexandre.belloni, slongerbeam, vitor.soares
  Cc: praneeth, mparab, linux-i3c, linux-kernel, Parshuram Thombare

add i3c_secondary_master_register which is used
to register secondary masters.

Signed-off-by: Parshuram Thombare <pthombar@cadence.com>
---
 drivers/i3c/master.c       |  154 +++++++++++++++++++++++++++++++++++++++++++-
 include/linux/i3c/master.h |    3 +
 2 files changed, 156 insertions(+), 1 deletions(-)

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 56e8fe4..af0630a 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -1797,6 +1797,90 @@ static int i3c_primary_master_bus_init(struct i3c_master_controller *master)
 	return ret;
 }
 
+/**
+ * i3c_secondary_master_bus_init() - initialize an I3C bus for secondary
+ * master
+ * @master: secondary master initializing the bus
+ *
+ * This function does
+ *
+ * 1. Attach I2C devs to the master
+ *
+ * 2. Call &i3c_master_controller_ops->bus_init() method to initialize
+ *    the master controller. That's usually where the bus mode is selected
+ *    (pure bus or mixed fast/slow bus)
+ *
+ * Once this is done, I2C devices should be usable.
+ *
+ * Return: a 0 in case of success, an negative error code otherwise.
+ */
+static int i3c_secondary_master_bus_init(struct i3c_master_controller *master)
+{
+	enum i3c_addr_slot_status status;
+	struct i2c_dev_boardinfo *i2cboardinfo;
+	struct i2c_dev_desc *i2cdev;
+	int ret;
+
+	/*
+	 * First attach all devices with static definitions provided by the
+	 * FW.
+	 */
+	list_for_each_entry(i2cboardinfo, &master->boardinfo.i2c, node) {
+		status = i3c_bus_get_addr_slot_status(&master->bus,
+						      i2cboardinfo->base.addr);
+		if (status != I3C_ADDR_SLOT_FREE) {
+			ret = -EBUSY;
+			goto err_detach_devs;
+		}
+
+		i3c_bus_set_addr_slot_status(&master->bus,
+					     i2cboardinfo->base.addr,
+					     I3C_ADDR_SLOT_I2C_DEV);
+
+		i2cdev = i3c_master_alloc_i2c_dev(master, i2cboardinfo);
+		if (IS_ERR(i2cdev)) {
+			ret = PTR_ERR(i2cdev);
+			goto err_detach_devs;
+		}
+
+		ret = i3c_master_attach_i2c_dev(master, i2cdev);
+		if (ret) {
+			i3c_master_free_i2c_dev(i2cdev);
+			goto err_detach_devs;
+		}
+	}
+
+	/*
+	 * Now execute the controller specific ->bus_init() routine, which
+	 * might configure its internal logic to match the bus limitations.
+	 */
+	ret = master->ops->bus_init(master);
+	if (ret)
+		goto err_detach_devs;
+
+	/*
+	 * The master device should have been instantiated in ->bus_init(),
+	 * complain if this was not the case.
+	 */
+	if (!master->this) {
+		dev_err(&master->dev,
+			"master_set_info() was not called in ->bus_init()\n");
+		ret = -EINVAL;
+		goto err_bus_cleanup;
+	}
+
+	return 0;
+
+err_bus_cleanup:
+	if (master->ops->bus_cleanup)
+		master->ops->bus_cleanup(master);
+
+err_detach_devs:
+	i3c_master_detach_free_devs(master);
+
+	return ret;
+}
+
 static void i3c_master_bus_cleanup(struct i3c_master_controller *master)
 {
 	if (master->ops->bus_cleanup)
@@ -2514,7 +2598,10 @@ static int i3c_master_init(struct i3c_master_controller *master,
 		goto err_put_dev;
 	}
 
-	ret = i3c_primary_master_bus_init(master);
+	if (secondary)
+		ret = i3c_secondary_master_bus_init(master);
+	else
+		ret = i3c_primary_master_bus_init(master);
 	if (ret)
 		goto err_destroy_wq;
 
@@ -2595,6 +2682,71 @@ int i3c_primary_master_register(struct i3c_master_controller *master,
 EXPORT_SYMBOL_GPL(i3c_primary_master_register);
 
 /**
+ * i3c_secondary_master_register() - register an I3C secondary master
+ * @master: master used to send frames on the bus
+ * @parent: the parent device (the one that provides this I3C master
+ *	    controller)
+ * @ops: the master controller operations
+ *
+ * This function does minimal required initialization for secondary
+ * master, rest functionality like creating and registering I2C
+ * and I3C devices is done in defslvs processing.
+ *
+ *  i3c_secondary_master_register() does following things -
+ * - creates and initializes the I3C bus
+ * - populates the bus with static I2C devs if @parent->of_node is not
+ *   NULL
+ *   initialization
+ * - allocate memory for defslvs_data.devs, which is used to receive
+ *   defslvs list
+ * - create I3C device representing this master
+ * - registers the I2C adapter and all I2C devices
+ *
+ * Return: 0 in case of success, a negative error code otherwise.
+ */
+int i3c_secondary_master_register(struct i3c_master_controller *master,
+				  struct device *parent,
+				  const struct i3c_master_controller_ops *ops)
+{
+	int ret;
+
+	ret = i3c_master_init(master, parent, ops, true);
+	if (ret)
+		return ret;
+
+	ret = device_add(&master->dev);
+	if (ret)
+		goto err_cleanup_bus;
+
+	/*
+	 * Expose our I3C bus as an I2C adapter so that I2C devices are exposed
+	 * through the I2C subsystem.
+	 */
+	ret = i3c_master_i2c_adapter_init(master);
+	if (ret)
+		goto err_del_dev;
+
+	/*
+	 * We're done initializing the bus and the controller, we can now
+	 * register I3C devices from defslvs list.
+	 */
+	master->init_done = true;
+
+	return 0;
+
+err_del_dev:
+	device_del(&master->dev);
+
+err_cleanup_bus:
+	i3c_master_bus_cleanup(master);
+
+	put_device(&master->dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(i3c_secondary_master_register);
+
+/**
  * 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 e543f68..e186d53 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -541,6 +541,9 @@ int i3c_master_set_info(struct i3c_master_controller *master,
 int i3c_primary_master_register(struct i3c_master_controller *master,
 				struct device *parent,
 				const struct i3c_master_controller_ops *ops);
+int i3c_secondary_master_register(struct i3c_master_controller *master,
+				  struct device *parent,
+				  const struct i3c_master_controller_ops *ops);
 int i3c_master_unregister(struct i3c_master_controller *master);
 
 /**
-- 
1.7.1


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^ permalink raw reply	[flat|nested] 11+ messages in thread

end of thread, other threads:[~2021-03-04  9:43 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-11-29 14:19 [RESEND PATCH v9 0/7] I3C mastership handover support Parshuram Thombare
2020-11-29 14:20 ` [PATCH v9 1/7] i3c: master: master initialization flow document Parshuram Thombare
2020-11-29 14:22 ` [PATCH v9 2/7] i3c: master: use i3c_master_register only for main master Parshuram Thombare
2020-11-29 17:12   ` kernel test robot
2020-11-29 14:22 ` [PATCH v9 3/7] i3c: master: add i3c_secondary_master_register Parshuram Thombare
2020-11-29 14:23 ` [PATCH v9 4/7] i3c: master: add mastership handover support Parshuram Thombare
2020-11-29 14:23 ` [PATCH v9 5/7] i3c: master: add defslvs processing Parshuram Thombare
2020-11-29 14:23 ` [PATCH v9 6/7] i3c: master: sysfs key for acquire bus Parshuram Thombare
2020-11-29 14:24 ` [PATCH v9 7/7] i3c: master: mastership handover, defslvs processing in cdns controller driver Parshuram Thombare
2021-03-04  9:42 ` [RESEND PATCH v9 0/7] I3C mastership handover support Parshuram Raju Thombare
  -- strict thread matches above, loose matches on Subject: below --
2020-11-28 14:46 [PATCH v9 3/7] i3c: master: add i3c_secondary_master_register Parshuram Thombare

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