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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/platform/x86/dell/dell-smo8800.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/platform/x86/dell/dell-smo8800.c')
-rw-r--r--drivers/platform/x86/dell/dell-smo8800.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/platform/x86/dell/dell-smo8800.c b/drivers/platform/x86/dell/dell-smo8800.c
new file mode 100644
index 000000000..3385e8521
--- /dev/null
+++ b/drivers/platform/x86/dell/dell-smo8800.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * dell-smo8800.c - Dell Latitude ACPI SMO88XX freefall sensor driver
+ *
+ * Copyright (C) 2012 Sonal Santan <sonal.santan@gmail.com>
+ * Copyright (C) 2014 Pali Rohár <pali@kernel.org>
+ *
+ * This is loosely based on lis3lv02d driver.
+ */
+
+#define DRIVER_NAME "smo8800"
+
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+
+struct smo8800_device {
+ u32 irq; /* acpi device irq */
+ atomic_t counter; /* count after last read */
+ struct miscdevice miscdev; /* for /dev/freefall */
+ unsigned long misc_opened; /* whether the device is open */
+ wait_queue_head_t misc_wait; /* Wait queue for the misc dev */
+ struct device *dev; /* acpi device */
+};
+
+static irqreturn_t smo8800_interrupt_quick(int irq, void *data)
+{
+ struct smo8800_device *smo8800 = data;
+
+ atomic_inc(&smo8800->counter);
+ wake_up_interruptible(&smo8800->misc_wait);
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t smo8800_interrupt_thread(int irq, void *data)
+{
+ struct smo8800_device *smo8800 = data;
+
+ dev_info(smo8800->dev, "detected free fall\n");
+ return IRQ_HANDLED;
+}
+
+static ssize_t smo8800_misc_read(struct file *file, char __user *buf,
+ size_t count, loff_t *pos)
+{
+ struct smo8800_device *smo8800 = container_of(file->private_data,
+ struct smo8800_device, miscdev);
+
+ u32 data = 0;
+ unsigned char byte_data;
+ ssize_t retval = 1;
+
+ if (count < 1)
+ return -EINVAL;
+
+ atomic_set(&smo8800->counter, 0);
+ retval = wait_event_interruptible(smo8800->misc_wait,
+ (data = atomic_xchg(&smo8800->counter, 0)));
+
+ if (retval)
+ return retval;
+
+ retval = 1;
+
+ if (data < 255)
+ byte_data = data;
+ else
+ byte_data = 255;
+
+ if (put_user(byte_data, buf))
+ retval = -EFAULT;
+
+ return retval;
+}
+
+static int smo8800_misc_open(struct inode *inode, struct file *file)
+{
+ struct smo8800_device *smo8800 = container_of(file->private_data,
+ struct smo8800_device, miscdev);
+
+ if (test_and_set_bit(0, &smo8800->misc_opened))
+ return -EBUSY; /* already open */
+
+ atomic_set(&smo8800->counter, 0);
+ return 0;
+}
+
+static int smo8800_misc_release(struct inode *inode, struct file *file)
+{
+ struct smo8800_device *smo8800 = container_of(file->private_data,
+ struct smo8800_device, miscdev);
+
+ clear_bit(0, &smo8800->misc_opened); /* release the device */
+ return 0;
+}
+
+static const struct file_operations smo8800_misc_fops = {
+ .owner = THIS_MODULE,
+ .read = smo8800_misc_read,
+ .open = smo8800_misc_open,
+ .release = smo8800_misc_release,
+};
+
+static int smo8800_probe(struct platform_device *device)
+{
+ int err;
+ struct smo8800_device *smo8800;
+
+ smo8800 = devm_kzalloc(&device->dev, sizeof(*smo8800), GFP_KERNEL);
+ if (!smo8800) {
+ dev_err(&device->dev, "failed to allocate device data\n");
+ return -ENOMEM;
+ }
+
+ smo8800->dev = &device->dev;
+ smo8800->miscdev.minor = MISC_DYNAMIC_MINOR;
+ smo8800->miscdev.name = "freefall";
+ smo8800->miscdev.fops = &smo8800_misc_fops;
+
+ init_waitqueue_head(&smo8800->misc_wait);
+
+ err = misc_register(&smo8800->miscdev);
+ if (err) {
+ dev_err(&device->dev, "failed to register misc dev: %d\n", err);
+ return err;
+ }
+
+ platform_set_drvdata(device, smo8800);
+
+ err = platform_get_irq(device, 0);
+ if (err < 0)
+ goto error;
+ smo8800->irq = err;
+
+ err = request_threaded_irq(smo8800->irq, smo8800_interrupt_quick,
+ smo8800_interrupt_thread,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ DRIVER_NAME, smo8800);
+ if (err) {
+ dev_err(&device->dev,
+ "failed to request thread for IRQ %d: %d\n",
+ smo8800->irq, err);
+ goto error;
+ }
+
+ dev_dbg(&device->dev, "device /dev/freefall registered with IRQ %d\n",
+ smo8800->irq);
+ return 0;
+
+error:
+ misc_deregister(&smo8800->miscdev);
+ return err;
+}
+
+static int smo8800_remove(struct platform_device *device)
+{
+ struct smo8800_device *smo8800 = platform_get_drvdata(device);
+
+ free_irq(smo8800->irq, smo8800);
+ misc_deregister(&smo8800->miscdev);
+ dev_dbg(&device->dev, "device /dev/freefall unregistered\n");
+ return 0;
+}
+
+/* NOTE: Keep this list in sync with drivers/i2c/busses/i2c-i801.c */
+static const struct acpi_device_id smo8800_ids[] = {
+ { "SMO8800", 0 },
+ { "SMO8801", 0 },
+ { "SMO8810", 0 },
+ { "SMO8811", 0 },
+ { "SMO8820", 0 },
+ { "SMO8821", 0 },
+ { "SMO8830", 0 },
+ { "SMO8831", 0 },
+ { "", 0 },
+};
+MODULE_DEVICE_TABLE(acpi, smo8800_ids);
+
+static struct platform_driver smo8800_driver = {
+ .probe = smo8800_probe,
+ .remove = smo8800_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .acpi_match_table = smo8800_ids,
+ },
+};
+module_platform_driver(smo8800_driver);
+
+MODULE_DESCRIPTION("Dell Latitude freefall driver (ACPI SMO88XX)");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sonal Santan, Pali Rohár");