// SPDX-License-Identifier: GPL-2.0-or-later /* * ACPI Ambient Light Sensor Driver * * Based on ALS driver: * Copyright (C) 2009 Zhang Rui * * Rework for IIO subsystem: * Copyright (C) 2012-2013 Martin Liska * * Final cleanup and debugging: * Copyright (C) 2013-2014 Marek Vasut * Copyright (C) 2015 Gabriele Mazzotta */ #include #include #include #include #include #include #include #include #include #include #define ACPI_ALS_CLASS "als" #define ACPI_ALS_DEVICE_NAME "acpi-als" #define ACPI_ALS_NOTIFY_ILLUMINANCE 0x80 /* * So far, there's only one channel in here, but the specification for * ACPI0008 says there can be more to what the block can report. Like * chromaticity and such. We are ready for incoming additions! */ static const struct iio_chan_spec acpi_als_channels[] = { { .type = IIO_LIGHT, .scan_type = { .sign = 's', .realbits = 32, .storagebits = 32, }, /* _RAW is here for backward ABI compatibility */ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED), }, IIO_CHAN_SOFT_TIMESTAMP(1), }; /* * The event buffer contains timestamp and all the data from * the ACPI0008 block. There are multiple, but so far we only * support _ALI (illuminance): One channel, padding and timestamp. */ #define ACPI_ALS_EVT_BUFFER_SIZE \ (sizeof(s32) + sizeof(s32) + sizeof(s64)) struct acpi_als { struct acpi_device *device; struct mutex lock; struct iio_trigger *trig; s32 evt_buffer[ACPI_ALS_EVT_BUFFER_SIZE / sizeof(s32)] __aligned(8); }; /* * All types of properties the ACPI0008 block can report. The ALI, ALC, ALT * and ALP can all be handled by acpi_als_read_value() below, while the ALR is * special. * * The _ALR property returns tables that can be used to fine-tune the values * reported by the other props based on the particular hardware type and it's * location (it contains tables for "rainy", "bright inhouse lighting" etc.). * * So far, we support only ALI (illuminance). */ #define ACPI_ALS_ILLUMINANCE "_ALI" #define ACPI_ALS_CHROMATICITY "_ALC" #define ACPI_ALS_COLOR_TEMP "_ALT" #define ACPI_ALS_POLLING "_ALP" #define ACPI_ALS_TABLES "_ALR" static int acpi_als_read_value(struct acpi_als *als, char *prop, s32 *val) { unsigned long long temp_val; acpi_status status; status = acpi_evaluate_integer(als->device->handle, prop, NULL, &temp_val); if (ACPI_FAILURE(status)) { acpi_evaluation_failure_warn(als->device->handle, prop, status); return -EIO; } *val = temp_val; return 0; } static void acpi_als_notify(struct acpi_device *device, u32 event) { struct iio_dev *indio_dev = acpi_driver_data(device); struct acpi_als *als = iio_priv(indio_dev); if (iio_buffer_enabled(indio_dev) && iio_trigger_using_own(indio_dev)) { switch (event) { case ACPI_ALS_NOTIFY_ILLUMINANCE: iio_trigger_poll_nested(als->trig); break; default: /* Unhandled event */ dev_dbg(&device->dev, "Unhandled ACPI ALS event (%08x)!\n", event); } } } static int acpi_als_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct acpi_als *als = iio_priv(indio_dev); s32 temp_val; int ret; if ((mask != IIO_CHAN_INFO_PROCESSED) && (mask != IIO_CHAN_INFO_RAW)) return -EINVAL; /* we support only illumination (_ALI) so far. */ if (chan->type != IIO_LIGHT) return -EINVAL; ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &temp_val); if (ret < 0) return ret; *val = temp_val; return IIO_VAL_INT; } static const struct iio_info acpi_als_info = { .read_raw = acpi_als_read_raw, }; static irqreturn_t acpi_als_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct acpi_als *als = iio_priv(indio_dev); s32 *buffer = als->evt_buffer; s32 val; int ret; mutex_lock(&als->lock); ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &val); if (ret < 0) goto out; *buffer = val; /* * When coming from own trigger via polls, set polling function * timestamp here. Given ACPI notifier is already in a thread and call * function directly, there is no need to set the timestamp in the * notify function. * * If the timestamp was actually 0, the timestamp is set one more time. */ if (!pf->timestamp) pf->timestamp = iio_get_time_ns(indio_dev); iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp); out: mutex_unlock(&als->lock); iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int acpi_als_add(struct acpi_device *device) { struct device *dev = &device->dev; struct iio_dev *indio_dev; struct acpi_als *als; int ret; indio_dev = devm_iio_device_alloc(dev, sizeof(*als)); if (!indio_dev) return -ENOMEM; als = iio_priv(indio_dev); device->driver_data = indio_dev; als->device = device; mutex_init(&als->lock); indio_dev->name = ACPI_ALS_DEVICE_NAME; indio_dev->info = &acpi_als_info; indio_dev->channels = acpi_als_channels; indio_dev->num_channels = ARRAY_SIZE(acpi_als_channels); als->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name, iio_device_id(indio_dev)); if (!als->trig) return -ENOMEM; ret = devm_iio_trigger_register(dev, als->trig); if (ret) return ret; /* * Set hardware trigger by default to let events flow when * BIOS support notification. */ indio_dev->trig = iio_trigger_get(als->trig); ret = devm_iio_triggered_buffer_setup(dev, indio_dev, iio_pollfunc_store_time, acpi_als_trigger_handler, NULL); if (ret) return ret; return devm_iio_device_register(dev, indio_dev); } static const struct acpi_device_id acpi_als_device_ids[] = { {"ACPI0008", 0}, {}, }; MODULE_DEVICE_TABLE(acpi, acpi_als_device_ids); static struct acpi_driver acpi_als_driver = { .name = "acpi_als", .class = ACPI_ALS_CLASS, .ids = acpi_als_device_ids, .ops = { .add = acpi_als_add, .notify = acpi_als_notify, }, }; module_acpi_driver(acpi_als_driver); MODULE_AUTHOR("Zhang Rui "); MODULE_AUTHOR("Martin Liska "); MODULE_AUTHOR("Marek Vasut "); MODULE_DESCRIPTION("ACPI Ambient Light Sensor Driver"); MODULE_LICENSE("GPL");