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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/input/misc/max7360-rotary.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
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 ...
Diffstat (limited to 'drivers/input/misc/max7360-rotary.c')
-rw-r--r--drivers/input/misc/max7360-rotary.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/input/misc/max7360-rotary.c b/drivers/input/misc/max7360-rotary.c
new file mode 100644
index 000000000..385831ef3
--- /dev/null
+++ b/drivers/input/misc/max7360-rotary.c
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2025 Bootlin
+ *
+ * Author: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/device/devres.h>
+#include <linux/dev_printk.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/max7360.h>
+#include <linux/property.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/regmap.h>
+#include <linux/types.h>
+
+#define MAX7360_ROTARY_DEFAULT_STEPS 24
+
+struct max7360_rotary {
+ struct input_dev *input;
+ struct regmap *regmap;
+ unsigned int debounce_ms;
+
+ unsigned int pos;
+
+ u32 steps;
+ u32 axis;
+ bool relative_axis;
+ bool rollover;
+};
+
+static void max7360_rotary_report_event(struct max7360_rotary *max7360_rotary, int steps)
+{
+ if (max7360_rotary->relative_axis) {
+ input_report_rel(max7360_rotary->input, max7360_rotary->axis, steps);
+ } else {
+ int pos = max7360_rotary->pos;
+ int maxval = max7360_rotary->steps;
+
+ /*
+ * Add steps to the position.
+ * Make sure added steps are always in ]-maxval; maxval[
+ * interval, so (pos + maxval) is always >= 0.
+ * Then set back pos to the [0; maxval[ interval.
+ */
+ pos += steps % maxval;
+ if (max7360_rotary->rollover)
+ pos = (pos + maxval) % maxval;
+ else
+ pos = clamp(pos, 0, maxval - 1);
+
+ max7360_rotary->pos = pos;
+ input_report_abs(max7360_rotary->input, max7360_rotary->axis, max7360_rotary->pos);
+ }
+
+ input_sync(max7360_rotary->input);
+}
+
+static irqreturn_t max7360_rotary_irq(int irq, void *data)
+{
+ struct max7360_rotary *max7360_rotary = data;
+ struct device *dev = max7360_rotary->input->dev.parent;
+ unsigned int val;
+ int error;
+
+ error = regmap_read(max7360_rotary->regmap, MAX7360_REG_RTR_CNT, &val);
+ if (error < 0) {
+ dev_err(dev, "Failed to read rotary counter\n");
+ return IRQ_NONE;
+ }
+
+ if (val == 0)
+ return IRQ_NONE;
+
+ max7360_rotary_report_event(max7360_rotary, sign_extend32(val, 7));
+
+ return IRQ_HANDLED;
+}
+
+static int max7360_rotary_hw_init(struct max7360_rotary *max7360_rotary)
+{
+ struct device *dev = max7360_rotary->input->dev.parent;
+ int val;
+ int error;
+
+ val = FIELD_PREP(MAX7360_ROT_DEBOUNCE, max7360_rotary->debounce_ms) |
+ FIELD_PREP(MAX7360_ROT_INTCNT, 1) | MAX7360_ROT_INTCNT_DLY;
+ error = regmap_write(max7360_rotary->regmap, MAX7360_REG_RTRCFG, val);
+ if (error)
+ dev_err(dev, "Failed to set max7360 rotary encoder configuration\n");
+
+ return error;
+}
+
+static int max7360_rotary_probe(struct platform_device *pdev)
+{
+ struct max7360_rotary *max7360_rotary;
+ struct device *dev = &pdev->dev;
+ struct input_dev *input;
+ struct regmap *regmap;
+ int irq;
+ int error;
+
+ regmap = dev_get_regmap(dev->parent, NULL);
+ if (!regmap)
+ return dev_err_probe(dev, -ENODEV, "Could not get parent regmap\n");
+
+ irq = fwnode_irq_get_byname(dev_fwnode(dev->parent), "inti");
+ if (irq < 0)
+ return dev_err_probe(dev, irq, "Failed to get IRQ\n");
+
+ max7360_rotary = devm_kzalloc(dev, sizeof(*max7360_rotary), GFP_KERNEL);
+ if (!max7360_rotary)
+ return -ENOMEM;
+
+ max7360_rotary->regmap = regmap;
+
+ device_property_read_u32(dev->parent, "linux,axis", &max7360_rotary->axis);
+ max7360_rotary->rollover = device_property_read_bool(dev->parent,
+ "rotary-encoder,rollover");
+ max7360_rotary->relative_axis =
+ device_property_read_bool(dev->parent, "rotary-encoder,relative-axis");
+
+ error = device_property_read_u32(dev->parent, "rotary-encoder,steps",
+ &max7360_rotary->steps);
+ if (error)
+ max7360_rotary->steps = MAX7360_ROTARY_DEFAULT_STEPS;
+
+ device_property_read_u32(dev->parent, "rotary-debounce-delay-ms",
+ &max7360_rotary->debounce_ms);
+ if (max7360_rotary->debounce_ms > MAX7360_ROT_DEBOUNCE_MAX)
+ return dev_err_probe(dev, -EINVAL, "Invalid debounce timing: %u\n",
+ max7360_rotary->debounce_ms);
+
+ input = devm_input_allocate_device(dev);
+ if (!input)
+ return -ENOMEM;
+
+ max7360_rotary->input = input;
+
+ input->id.bustype = BUS_I2C;
+ input->name = pdev->name;
+
+ if (max7360_rotary->relative_axis)
+ input_set_capability(input, EV_REL, max7360_rotary->axis);
+ else
+ input_set_abs_params(input, max7360_rotary->axis, 0, max7360_rotary->steps, 0, 1);
+
+ error = devm_request_threaded_irq(dev, irq, NULL, max7360_rotary_irq,
+ IRQF_ONESHOT | IRQF_SHARED,
+ "max7360-rotary", max7360_rotary);
+ if (error)
+ return dev_err_probe(dev, error, "Failed to register interrupt\n");
+
+ error = input_register_device(input);
+ if (error)
+ return dev_err_probe(dev, error, "Could not register input device\n");
+
+ error = max7360_rotary_hw_init(max7360_rotary);
+ if (error)
+ return dev_err_probe(dev, error, "Failed to initialize max7360 rotary\n");
+
+ device_init_wakeup(dev, true);
+ error = dev_pm_set_wake_irq(dev, irq);
+ if (error)
+ dev_warn(dev, "Failed to set up wakeup irq: %d\n", error);
+
+ return 0;
+}
+
+static void max7360_rotary_remove(struct platform_device *pdev)
+{
+ dev_pm_clear_wake_irq(&pdev->dev);
+ device_init_wakeup(&pdev->dev, false);
+}
+
+static struct platform_driver max7360_rotary_driver = {
+ .driver = {
+ .name = "max7360-rotary",
+ },
+ .probe = max7360_rotary_probe,
+ .remove = max7360_rotary_remove,
+};
+module_platform_driver(max7360_rotary_driver);
+
+MODULE_DESCRIPTION("MAX7360 Rotary driver");
+MODULE_AUTHOR("Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>");
+MODULE_LICENSE("GPL");