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* [PATCH v3] platform/chrome: chromeos_acpi: print hex string for ACPI_TYPE_BUFFER
@ 2023-08-03  1:12 Tzung-Bi Shih
  2023-08-10  0:35 ` Guenter Roeck
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Tzung-Bi Shih @ 2023-08-03  1:12 UTC (permalink / raw)
  To: bleung, groeck
  Cc: chrome-platform, guillaume.tucker, denys.f, ricardo.canuelo,
	usama.anjum, tzungbi, briannorris

`element->buffer.pointer` should be binary blob.  `%s` doesn't work
perfect for them.

Print hex string for ACPI_TYPE_BUFFER.  Also update the documentation
to reflect this.

Fixes: 0a4cad9c11ad ("platform/chrome: Add ChromeOS ACPI device driver")
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
Changes from v2[1]:
- Use dev_info_once() instead of dev_info().
- Update documentation.
- Add Fixes tag.

Changes from v1[2]:
- Use hex_dump_to_buffer().
- Rewrite the loop for catching edge cases for truncating.

[1]: https://patchwork.kernel.org/project/chrome-platform/patch/20230802095736.3079963-1-tzungbi@kernel.org/
[2]: https://patchwork.kernel.org/project/chrome-platform/patch/20230726073127.2969387-1-tzungbi@kernel.org/

 .../ABI/testing/sysfs-driver-chromeos-acpi    |  2 +-
 drivers/platform/chrome/chromeos_acpi.c       | 31 ++++++++++++++++++-
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-driver-chromeos-acpi b/Documentation/ABI/testing/sysfs-driver-chromeos-acpi
index c308926e1568..7c8e129fc100 100644
--- a/Documentation/ABI/testing/sysfs-driver-chromeos-acpi
+++ b/Documentation/ABI/testing/sysfs-driver-chromeos-acpi
@@ -134,4 +134,4 @@ KernelVersion:	5.19
 Description:
 		Returns the verified boot data block shared between the
 		firmware verification step and the kernel verification step
-		(binary).
+		(hex dump).
diff --git a/drivers/platform/chrome/chromeos_acpi.c b/drivers/platform/chrome/chromeos_acpi.c
index 50d8a4d4352d..1312aaaa8750 100644
--- a/drivers/platform/chrome/chromeos_acpi.c
+++ b/drivers/platform/chrome/chromeos_acpi.c
@@ -90,7 +90,36 @@ static int chromeos_acpi_handle_package(struct device *dev, union acpi_object *o
 	case ACPI_TYPE_STRING:
 		return sysfs_emit(buf, "%s\n", element->string.pointer);
 	case ACPI_TYPE_BUFFER:
-		return sysfs_emit(buf, "%s\n", element->buffer.pointer);
+		{
+			int i, r, at, room_left;
+			const int byte_per_line = 16;
+
+			at = 0;
+			room_left = PAGE_SIZE - 1;
+			for (i = 0; i < element->buffer.length && room_left; i += byte_per_line) {
+				r = hex_dump_to_buffer(element->buffer.pointer + i,
+						       element->buffer.length - i,
+						       byte_per_line, 1, buf + at, room_left,
+						       false);
+				if (r > room_left)
+					goto truncating;
+				at += r;
+				room_left -= r;
+
+				r = sysfs_emit_at(buf, at, "\n");
+				if (!r)
+					goto truncating;
+				at += r;
+				room_left -= r;
+			}
+
+			buf[at] = 0;
+			return at;
+truncating:
+			dev_info_once(dev, "truncating sysfs content for %s\n", name);
+			sysfs_emit_at(buf, PAGE_SIZE - 4, "..\n");
+			return PAGE_SIZE - 1;
+		}
 	default:
 		dev_err(dev, "element type %d not supported\n", element->type);
 		return -EINVAL;
-- 
2.41.0.585.gd2178a4bd4-goog


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2023-08-11  4:30 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-08-03  1:12 [PATCH v3] platform/chrome: chromeos_acpi: print hex string for ACPI_TYPE_BUFFER Tzung-Bi Shih
2023-08-10  0:35 ` Guenter Roeck
2023-08-10  3:20 ` patchwork-bot+chrome-platform
2023-08-11  4:30 ` patchwork-bot+chrome-platform

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