From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Date: Sat, 2 Aug 2025 16:44:26 +0000 (+0100)
Subject: iio: light: acpi-als: Use a structure for layout of data to push to buffer.
X-Git-Tag: v6.18-rc1~74^2~7^2~118
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=783efeb58fefb13911a3f47d6e38a32780359f10;p=thirdparty%2Fkernel%2Fstable.git

iio: light: acpi-als: Use a structure for layout of data to push to buffer.

Using a structure makes the padding and alignment rules explicit,
removing the need for a comment.

Also move the storage to the stack as it is only 16 bytes.

Cc: Gwendal Grignou <gwendal@chromium.org>
Link: https://patch.msgid.link/20250802164436.515988-7-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
---

diff --git a/drivers/iio/light/acpi-als.c b/drivers/iio/light/acpi-als.c
index 032e6cae8b805..511ed37e783ed 100644
--- a/drivers/iio/light/acpi-als.c
+++ b/drivers/iio/light/acpi-als.c
@@ -49,20 +49,10 @@ static const struct iio_chan_spec acpi_als_channels[] = {
 	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);
 };
 
 /*
@@ -152,7 +142,10 @@ 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;
+	struct {
+		s32 light;
+		aligned_s64 ts;
+	} scan = { };
 	s32 val;
 	int ret;
 
@@ -161,7 +154,7 @@ static irqreturn_t acpi_als_trigger_handler(int irq, void *p)
 	ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &val);
 	if (ret < 0)
 		goto out;
-	*buffer = val;
+	scan.light = val;
 
 	/*
 	 * When coming from own trigger via polls, set polling function
@@ -174,7 +167,7 @@ static irqreturn_t acpi_als_trigger_handler(int irq, void *p)
 	if (!pf->timestamp)
 		pf->timestamp = iio_get_time_ns(indio_dev);
 
-	iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp);
+	iio_push_to_buffers_with_timestamp(indio_dev, &scan, pf->timestamp);
 out:
 	mutex_unlock(&als->lock);
 	iio_trigger_notify_done(indio_dev->trig);