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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
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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 ...
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+========================================
+Writing Device Drivers for Zorro Devices
+========================================
+
+:Author: Written by Geert Uytterhoeven <geert@linux-m68k.org>
+:Last revised: September 5, 2003
+
+
+Introduction
+------------
+
+The Zorro bus is the bus used in the Amiga family of computers. Thanks to
+AutoConfig(tm), it's 100% Plug-and-Play.
+
+There are two types of Zorro buses, Zorro II and Zorro III:
+
+ - The Zorro II address space is 24-bit and lies within the first 16 MB of the
+ Amiga's address map.
+
+ - Zorro III is a 32-bit extension of Zorro II, which is backwards compatible
+ with Zorro II. The Zorro III address space lies outside the first 16 MB.
+
+
+Probing for Zorro Devices
+-------------------------
+
+Zorro devices are found by calling ``zorro_find_device()``, which returns a
+pointer to the ``next`` Zorro device with the specified Zorro ID. A probe loop
+for the board with Zorro ID ``ZORRO_PROD_xxx`` looks like::
+
+ struct zorro_dev *z = NULL;
+
+ while ((z = zorro_find_device(ZORRO_PROD_xxx, z))) {
+ if (!zorro_request_region(z->resource.start+MY_START, MY_SIZE,
+ "My explanation"))
+ ...
+ }
+
+``ZORRO_WILDCARD`` acts as a wildcard and finds any Zorro device. If your driver
+supports different types of boards, you can use a construct like::
+
+ struct zorro_dev *z = NULL;
+
+ while ((z = zorro_find_device(ZORRO_WILDCARD, z))) {
+ if (z->id != ZORRO_PROD_xxx1 && z->id != ZORRO_PROD_xxx2 && ...)
+ continue;
+ if (!zorro_request_region(z->resource.start+MY_START, MY_SIZE,
+ "My explanation"))
+ ...
+ }
+
+
+Zorro Resources
+---------------
+
+Before you can access a Zorro device's registers, you have to make sure it's
+not yet in use. This is done using the I/O memory space resource management
+functions::
+
+ request_mem_region()
+ release_mem_region()
+
+Shortcuts to claim the whole device's address space are provided as well::
+
+ zorro_request_device
+ zorro_release_device
+
+
+Accessing the Zorro Address Space
+---------------------------------
+
+The address regions in the Zorro device resources are Zorro bus address
+regions. Due to the identity bus-physical address mapping on the Zorro bus,
+they are CPU physical addresses as well.
+
+The treatment of these regions depends on the type of Zorro space:
+
+ - Zorro II address space is always mapped and does not have to be mapped
+ explicitly using z_ioremap().
+
+ Conversion from bus/physical Zorro II addresses to kernel virtual addresses
+ and vice versa is done using::
+
+ virt_addr = ZTWO_VADDR(bus_addr);
+ bus_addr = ZTWO_PADDR(virt_addr);
+
+ - Zorro III address space must be mapped explicitly using z_ioremap() first
+ before it can be accessed::
+
+ virt_addr = z_ioremap(bus_addr, size);
+ ...
+ z_iounmap(virt_addr);
+
+
+References
+----------
+
+#. linux/include/linux/zorro.h
+#. linux/include/uapi/linux/zorro.h
+#. linux/include/uapi/linux/zorro_ids.h
+#. linux/arch/m68k/include/asm/zorro.h
+#. linux/drivers/zorro
+#. /proc/bus/zorro
+