From 24b84444eb6f8d6a5090f6fdf172cacfa43f89e9 Mon Sep 17 00:00:00 2001 From: Gwendal Grignou Date: Wed, 17 Mar 2021 00:40:12 -0700 Subject: [PATCH] iio: acpi_als: Add trigger support As some firmware does not notify on illuminance changes, add a trigger to be able to query light via software (sysfs-trigger or hrtrigger). Add a hardware trigger set as the default trigger to maintain backward compatibility. Check iio_info reports the sensor as buffer capable: iio:device0: acpi-als (buffer capable) To test, check we can get data on demand on an Intel based chromebook: IIO_DEV="iio:device0" echo 1 > iio_sysfs_trigger/add_trigger cat trigger2/name > ${IIO_DEV}/trigger/current_trigger for i in ${IIO_DEV}/scan_elements/*_en ${IIO_DEV}/buffer/enable ; do echo 1 > $i done od -x /dev/${IIO_DEV} & echo 1 > trigger2/trigger_now Signed-off-by: Gwendal Grignou Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20210317074012.2336454-4-gwendal@chromium.org Signed-off-by: Jonathan Cameron --- drivers/iio/light/acpi-als.c | 96 +++++++++++++++++++++++++++++++------------- 1 file changed, 68 insertions(+), 28 deletions(-) diff --git a/drivers/iio/light/acpi-als.c b/drivers/iio/light/acpi-als.c index a210794..30393f0 100644 --- a/drivers/iio/light/acpi-als.c +++ b/drivers/iio/light/acpi-als.c @@ -16,11 +16,14 @@ #include #include #include +#include #include #include #include -#include +#include +#include +#include #define ACPI_ALS_CLASS "als" #define ACPI_ALS_DEVICE_NAME "acpi-als" @@ -59,6 +62,7 @@ static const struct iio_chan_spec acpi_als_channels[] = { 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); }; @@ -102,33 +106,19 @@ 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); - s32 *buffer = als->evt_buffer; - s64 time_ns = iio_get_time_ns(indio_dev); - s32 val; - int ret; - - mutex_lock(&als->lock); - memset(buffer, 0, ACPI_ALS_EVT_BUFFER_SIZE); - - switch (event) { - case ACPI_ALS_NOTIFY_ILLUMINANCE: - ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &val); - if (ret < 0) - goto out; - *buffer++ = val; - break; - default: - /* Unhandled event */ - dev_dbg(&device->dev, "Unhandled ACPI ALS event (%08x)!\n", - event); - goto out; + if (iio_buffer_enabled(indio_dev) && iio_trigger_using_own(indio_dev)) { + switch (event) { + case ACPI_ALS_NOTIFY_ILLUMINANCE: + iio_trigger_poll_chained(als->trig); + break; + default: + /* Unhandled event */ + dev_dbg(&device->dev, + "Unhandled ACPI ALS event (%08x)!\n", + event); + } } - - iio_push_to_buffers_with_timestamp(indio_dev, als->evt_buffer, time_ns); - -out: - mutex_unlock(&als->lock); } static int acpi_als_read_raw(struct iio_dev *indio_dev, @@ -159,6 +149,41 @@ 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; @@ -181,8 +206,23 @@ static int acpi_als_add(struct acpi_device *device) indio_dev->channels = acpi_als_channels; indio_dev->num_channels = ARRAY_SIZE(acpi_als_channels); - ret = devm_iio_kfifo_buffer_setup(dev, indio_dev, - INDIO_BUFFER_SOFTWARE, NULL); + als->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name, indio_dev->id); + 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; -- 2.7.4