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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+========================
+Null block device driver
+========================
+
+Overview
+========
+
+The null block device (``/dev/nullb*``) is used for benchmarking the various
+block-layer implementations. It emulates a block device of X gigabytes in size.
+It does not execute any read/write operation, just mark them as complete in
+the request queue. The following instances are possible:
+
+ Multi-queue block-layer
+
+ - Request-based.
+ - Configurable submission queues per device.
+
+ No block-layer (Known as bio-based)
+
+ - Bio-based. IO requests are submitted directly to the device driver.
+ - Directly accepts bio data structure and returns them.
+
+All of them have a completion queue for each core in the system.
+
+Module parameters
+=================
+
+queue_mode=[0-2]: Default: 2-Multi-queue
+ Selects which block-layer the module should instantiate with.
+
+ = ============
+ 0 Bio-based
+ 1 Single-queue (deprecated)
+ 2 Multi-queue
+ = ============
+
+home_node=[0--nr_nodes]: Default: NUMA_NO_NODE
+ Selects what CPU node the data structures are allocated from.
+
+gb=[Size in GB]: Default: 250GB
+ The size of the device reported to the system.
+
+bs=[Block size (in bytes)]: Default: 512 bytes
+ The block size reported to the system.
+
+nr_devices=[Number of devices]: Default: 1
+ Number of block devices instantiated. They are instantiated as /dev/nullb0,
+ etc.
+
+irqmode=[0-2]: Default: 1-Soft-irq
+ The completion mode used for completing IOs to the block-layer.
+
+ = ===========================================================================
+ 0 None.
+ 1 Soft-irq. Uses IPI to complete IOs across CPU nodes. Simulates the overhead
+ when IOs are issued from another CPU node than the home the device is
+ connected to.
+ 2 Timer: Waits a specific period (completion_nsec) for each IO before
+ completion.
+ = ===========================================================================
+
+completion_nsec=[ns]: Default: 10,000ns
+ Combined with irqmode=2 (timer). The time each completion event must wait.
+
+submit_queues=[1..nr_cpus]: Default: 1
+ The number of submission queues attached to the device driver. If unset, it
+ defaults to 1. For multi-queue, it is ignored when use_per_node_hctx module
+ parameter is 1.
+
+hw_queue_depth=[0..qdepth]: Default: 64
+ The hardware queue depth of the device.
+
+memory_backed=[0/1]: Default: 0
+ Whether or not to use a memory buffer to respond to IO requests
+
+ = =============================================
+ 0 Transfer no data in response to IO requests
+ 1 Use a memory buffer to respond to IO requests
+ = =============================================
+
+discard=[0/1]: Default: 0
+ Support discard operations (requires memory-backed null_blk device).
+
+ = =====================================
+ 0 Do not support discard operations
+ 1 Enable support for discard operations
+ = =====================================
+
+cache_size=[Size in MB]: Default: 0
+ Cache size in MB for memory-backed device.
+
+mbps=[Maximum bandwidth in MB/s]: Default: 0 (no limit)
+ Bandwidth limit for device performance.
+
+Multi-queue specific parameters
+-------------------------------
+
+use_per_node_hctx=[0/1]: Default: 0
+ Number of hardware context queues.
+
+ = =====================================================================
+ 0 The number of submit queues are set to the value of the submit_queues
+ parameter.
+ 1 The multi-queue block layer is instantiated with a hardware dispatch
+ queue for each CPU node in the system.
+ = =====================================================================
+
+no_sched=[0/1]: Default: 0
+ Enable/disable the io scheduler.
+
+ = ======================================
+ 0 nullb* use default blk-mq io scheduler
+ 1 nullb* doesn't use io scheduler
+ = ======================================
+
+blocking=[0/1]: Default: 0
+ Blocking behavior of the request queue.
+
+ = ===============================================================
+ 0 Register as a non-blocking blk-mq driver device.
+ 1 Register as a blocking blk-mq driver device, null_blk will set
+ the BLK_MQ_F_BLOCKING flag, indicating that it sometimes/always
+ needs to block in its ->queue_rq() function.
+ = ===============================================================
+
+shared_tags=[0/1]: Default: 0
+ Sharing tags between devices.
+
+ = ================================================================
+ 0 Tag set is not shared.
+ 1 Tag set shared between devices for blk-mq. Only makes sense with
+ nr_devices > 1, otherwise there's no tag set to share.
+ = ================================================================
+
+zoned=[0/1]: Default: 0
+ Device is a random-access or a zoned block device.
+
+ = ======================================================================
+ 0 Block device is exposed as a random-access block device.
+ 1 Block device is exposed as a host-managed zoned block device. Requires
+ CONFIG_BLK_DEV_ZONED.
+ = ======================================================================
+
+zone_size=[MB]: Default: 256
+ Per zone size when exposed as a zoned block device. Must be a power of two.
+
+zone_nr_conv=[nr_conv]: Default: 0
+ The number of conventional zones to create when block device is zoned. If
+ zone_nr_conv >= nr_zones, it will be reduced to nr_zones - 1.