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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
commit9f0346dcbea363787186c94ef94dd01aaa215afa (patch)
treeb81c168f4d0dbe4c7f4750f4598d48a6deb72094 /drivers/hwmon/kbatt.c
downloadlinux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz
linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
Diffstat (limited to 'drivers/hwmon/kbatt.c')
-rw-r--r--drivers/hwmon/kbatt.c147
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/hwmon/kbatt.c b/drivers/hwmon/kbatt.c
new file mode 100644
index 000000000..501b8f4de
--- /dev/null
+++ b/drivers/hwmon/kbatt.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2025 KEBA Industrial Automation GmbH
+ *
+ * Driver for KEBA battery monitoring controller FPGA IP core
+ */
+
+#include <linux/hwmon.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/misc/keba.h>
+#include <linux/mutex.h>
+
+#define KBATT "kbatt"
+
+#define KBATT_CONTROL_REG 0x4
+#define KBATT_CONTROL_BAT_TEST 0x01
+
+#define KBATT_STATUS_REG 0x8
+#define KBATT_STATUS_BAT_OK 0x01
+
+#define KBATT_MAX_UPD_INTERVAL (10 * HZ)
+#define KBATT_SETTLE_TIME_US (100 * USEC_PER_MSEC)
+
+struct kbatt {
+ /* update lock */
+ struct mutex lock;
+ void __iomem *base;
+
+ unsigned long next_update; /* in jiffies */
+ bool alarm;
+};
+
+static bool kbatt_alarm(struct kbatt *kbatt)
+{
+ mutex_lock(&kbatt->lock);
+
+ if (!kbatt->next_update || time_after(jiffies, kbatt->next_update)) {
+ /* switch load on */
+ iowrite8(KBATT_CONTROL_BAT_TEST,
+ kbatt->base + KBATT_CONTROL_REG);
+
+ /* wait some time to let things settle */
+ fsleep(KBATT_SETTLE_TIME_US);
+
+ /* check battery state */
+ if (ioread8(kbatt->base + KBATT_STATUS_REG) &
+ KBATT_STATUS_BAT_OK)
+ kbatt->alarm = false;
+ else
+ kbatt->alarm = true;
+
+ /* switch load off */
+ iowrite8(0, kbatt->base + KBATT_CONTROL_REG);
+
+ kbatt->next_update = jiffies + KBATT_MAX_UPD_INTERVAL;
+ }
+
+ mutex_unlock(&kbatt->lock);
+
+ return kbatt->alarm;
+}
+
+static int kbatt_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct kbatt *kbatt = dev_get_drvdata(dev);
+
+ *val = kbatt_alarm(kbatt) ? 1 : 0;
+
+ return 0;
+}
+
+static umode_t kbatt_is_visible(const void *data, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ if (channel == 0 && attr == hwmon_in_min_alarm)
+ return 0444;
+
+ return 0;
+}
+
+static const struct hwmon_channel_info *kbatt_info[] = {
+ HWMON_CHANNEL_INFO(in,
+ /* 0: input minimum alarm channel */
+ HWMON_I_MIN_ALARM),
+ NULL
+};
+
+static const struct hwmon_ops kbatt_hwmon_ops = {
+ .is_visible = kbatt_is_visible,
+ .read = kbatt_read,
+};
+
+static const struct hwmon_chip_info kbatt_chip_info = {
+ .ops = &kbatt_hwmon_ops,
+ .info = kbatt_info,
+};
+
+static int kbatt_probe(struct auxiliary_device *auxdev,
+ const struct auxiliary_device_id *id)
+{
+ struct keba_batt_auxdev *kbatt_auxdev =
+ container_of(auxdev, struct keba_batt_auxdev, auxdev);
+ struct device *dev = &auxdev->dev;
+ struct device *hwmon_dev;
+ struct kbatt *kbatt;
+ int retval;
+
+ kbatt = devm_kzalloc(dev, sizeof(*kbatt), GFP_KERNEL);
+ if (!kbatt)
+ return -ENOMEM;
+
+ retval = devm_mutex_init(dev, &kbatt->lock);
+ if (retval)
+ return retval;
+
+ kbatt->base = devm_ioremap_resource(dev, &kbatt_auxdev->io);
+ if (IS_ERR(kbatt->base))
+ return PTR_ERR(kbatt->base);
+
+ hwmon_dev = devm_hwmon_device_register_with_info(dev, KBATT, kbatt,
+ &kbatt_chip_info,
+ NULL);
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct auxiliary_device_id kbatt_devtype_aux[] = {
+ { .name = "keba.batt" },
+ {}
+};
+MODULE_DEVICE_TABLE(auxiliary, kbatt_devtype_aux);
+
+static struct auxiliary_driver kbatt_driver_aux = {
+ .name = KBATT,
+ .id_table = kbatt_devtype_aux,
+ .probe = kbatt_probe,
+};
+module_auxiliary_driver(kbatt_driver_aux);
+
+MODULE_AUTHOR("Petar Bojanic <boja@keba.com>");
+MODULE_AUTHOR("Gerhard Engleder <eg@keba.com>");
+MODULE_DESCRIPTION("KEBA battery monitoring controller driver");
+MODULE_LICENSE("GPL");