Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 259 insertions, 0 deletions

diff --git a/drivers/reset/reset-ti-sci.c b/drivers/reset/reset-ti-sci.c
new file mode 100644
index 000000000..1dc5b766a
--- /dev/null
+++ b/drivers/reset/reset-ti-sci.c
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Texas Instrument's System Control Interface (TI-SCI) reset driver
+ *
+ * Copyright (C) 2015-2017 Texas Instruments Incorporated - https://www.ti.com/
+ *	Andrew F. Davis <afd@ti.com>
+ */
+
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+
+/**
+ * struct ti_sci_reset_control - reset control structure
+ * @dev_id: SoC-specific device identifier
+ * @reset_mask: reset mask to use for toggling reset
+ * @lock: synchronize reset_mask read-modify-writes
+ */
+struct ti_sci_reset_control {
+	u32 dev_id;
+	u32 reset_mask;
+	struct mutex lock;
+};
+
+/**
+ * struct ti_sci_reset_data - reset controller information structure
+ * @rcdev: reset controller entity
+ * @dev: reset controller device pointer
+ * @sci: TI SCI handle used for communication with system controller
+ * @idr: idr structure for mapping ids to reset control structures
+ */
+struct ti_sci_reset_data {
+	struct reset_controller_dev rcdev;
+	struct device *dev;
+	const struct ti_sci_handle *sci;
+	struct idr idr;
+};
+
+#define to_ti_sci_reset_data(p)	\
+	container_of((p), struct ti_sci_reset_data, rcdev)
+
+/**
+ * ti_sci_reset_set() - program a device's reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to toggle
+ * @assert: boolean flag to indicate assert or deassert
+ *
+ * This is a common internal function used to assert or deassert a device's
+ * reset using the TI SCI protocol. The device's reset is asserted if the
+ * @assert argument is true, or deasserted if @assert argument is false.
+ * The mechanism itself is a read-modify-write procedure, the current device
+ * reset register is read using a TI SCI device operation, the new value is
+ * set or un-set using the reset's mask, and the new reset value written by
+ * using another TI SCI device operation.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_set(struct reset_controller_dev *rcdev,
+			    unsigned long id, bool assert)
+{
+	struct ti_sci_reset_data *data = to_ti_sci_reset_data(rcdev);
+	const struct ti_sci_handle *sci = data->sci;
+	const struct ti_sci_dev_ops *dev_ops = &sci->ops.dev_ops;
+	struct ti_sci_reset_control *control;
+	u32 reset_state;
+	int ret;
+
+	control = idr_find(&data->idr, id);
+	if (!control)
+		return -EINVAL;
+
+	mutex_lock(&control->lock);
+
+	ret = dev_ops->get_device_resets(sci, control->dev_id, &reset_state);
+	if (ret)
+		goto out;
+
+	if (assert)
+		reset_state |= control->reset_mask;
+	else
+		reset_state &= ~control->reset_mask;
+
+	ret = dev_ops->set_device_resets(sci, control->dev_id, reset_state);
+out:
+	mutex_unlock(&control->lock);
+
+	return ret;
+}
+
+/**
+ * ti_sci_reset_assert() - assert device reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to be asserted
+ *
+ * This function implements the reset driver op to assert a device's reset
+ * using the TI SCI protocol. This invokes the function ti_sci_reset_set()
+ * with the corresponding parameters as passed in, but with the @assert
+ * argument set to true for asserting the reset.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_assert(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	return ti_sci_reset_set(rcdev, id, true);
+}
+
+/**
+ * ti_sci_reset_deassert() - deassert device reset
+ * @rcdev: reset controller entity
+ * @id: ID of the reset to be deasserted
+ *
+ * This function implements the reset driver op to deassert a device's reset
+ * using the TI SCI protocol. This invokes the function ti_sci_reset_set()
+ * with the corresponding parameters as passed in, but with the @assert
+ * argument set to false for deasserting the reset.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_deassert(struct reset_controller_dev *rcdev,
+				 unsigned long id)
+{
+	return ti_sci_reset_set(rcdev, id, false);
+}
+
+/**
+ * ti_sci_reset_status() - check device reset status
+ * @rcdev: reset controller entity
+ * @id: ID of reset to be checked
+ *
+ * This function implements the reset driver op to return the status of a
+ * device's reset using the TI SCI protocol. The reset register value is read
+ * by invoking the TI SCI device operation .get_device_resets(), and the
+ * status of the specific reset is extracted and returned using this reset's
+ * reset mask.
+ *
+ * Return: 0 if reset is deasserted, or a non-zero value if reset is asserted
+ */
+static int ti_sci_reset_status(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	struct ti_sci_reset_data *data = to_ti_sci_reset_data(rcdev);
+	const struct ti_sci_handle *sci = data->sci;
+	const struct ti_sci_dev_ops *dev_ops = &sci->ops.dev_ops;
+	struct ti_sci_reset_control *control;
+	u32 reset_state;
+	int ret;
+
+	control = idr_find(&data->idr, id);
+	if (!control)
+		return -EINVAL;
+
+	ret = dev_ops->get_device_resets(sci, control->dev_id, &reset_state);
+	if (ret)
+		return ret;
+
+	return reset_state & control->reset_mask;
+}
+
+static const struct reset_control_ops ti_sci_reset_ops = {
+	.assert		= ti_sci_reset_assert,
+	.deassert	= ti_sci_reset_deassert,
+	.status		= ti_sci_reset_status,
+};
+
+/**
+ * ti_sci_reset_of_xlate() - translate a set of OF arguments to a reset ID
+ * @rcdev: reset controller entity
+ * @reset_spec: OF reset argument specifier
+ *
+ * This function performs the translation of the reset argument specifier
+ * values defined in a reset consumer device node. The function allocates a
+ * reset control structure for that device reset, and will be used by the
+ * driver for performing any reset functions on that reset. An idr structure
+ * is allocated and used to map to the reset control structure. This idr
+ * is used by the driver to do reset lookups.
+ *
+ * Return: 0 for successful request, else a corresponding error value
+ */
+static int ti_sci_reset_of_xlate(struct reset_controller_dev *rcdev,
+				 const struct of_phandle_args *reset_spec)
+{
+	struct ti_sci_reset_data *data = to_ti_sci_reset_data(rcdev);
+	struct ti_sci_reset_control *control;
+
+	if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
+		return -EINVAL;
+
+	control = devm_kzalloc(data->dev, sizeof(*control), GFP_KERNEL);
+	if (!control)
+		return -ENOMEM;
+
+	control->dev_id = reset_spec->args[0];
+	control->reset_mask = reset_spec->args[1];
+	mutex_init(&control->lock);
+
+	return idr_alloc(&data->idr, control, 0, 0, GFP_KERNEL);
+}
+
+static const struct of_device_id ti_sci_reset_of_match[] = {
+	{ .compatible = "ti,sci-reset", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ti_sci_reset_of_match);
+
+static int ti_sci_reset_probe(struct platform_device *pdev)
+{
+	struct ti_sci_reset_data *data;
+
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->sci = devm_ti_sci_get_handle(&pdev->dev);
+	if (IS_ERR(data->sci))
+		return PTR_ERR(data->sci);
+
+	data->rcdev.ops = &ti_sci_reset_ops;
+	data->rcdev.owner = THIS_MODULE;
+	data->rcdev.of_node = pdev->dev.of_node;
+	data->rcdev.of_reset_n_cells = 2;
+	data->rcdev.of_xlate = ti_sci_reset_of_xlate;
+	data->dev = &pdev->dev;
+	idr_init(&data->idr);
+
+	platform_set_drvdata(pdev, data);
+
+	return reset_controller_register(&data->rcdev);
+}
+
+static void ti_sci_reset_remove(struct platform_device *pdev)
+{
+	struct ti_sci_reset_data *data = platform_get_drvdata(pdev);
+
+	reset_controller_unregister(&data->rcdev);
+
+	idr_destroy(&data->idr);
+}
+
+static struct platform_driver ti_sci_reset_driver = {
+	.probe = ti_sci_reset_probe,
+	.remove = ti_sci_reset_remove,
+	.driver = {
+		.name = "ti-sci-reset",
+		.of_match_table = ti_sci_reset_of_match,
+	},
+};
+module_platform_driver(ti_sci_reset_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_DESCRIPTION("TI System Control Interface (TI SCI) Reset driver");
+MODULE_LICENSE("GPL v2");