Re: [PATCH v13 0/2] Support for Osram as3668 LED driver

From: Lee Jones

Date: Thu Jan 08 2026 - 06:51:30 EST


On Tue, 02 Dec 2025, Lukas Timmermann wrote:

Running through checkpatch.pl
total: 0 errors, 0 warnings, 86 lines checked

"[PATCH v13 1/2] dt-bindings: leds: Add new as3668 support" has no obvious style problems and is ready for submission.
ERROR: Macros with complex values should be enclosed in parentheses
#115: FILE: drivers/leds/leds-as3668.c:35:
+#define AS3668_CURR_MODE_PACK(mode) ((mode) << 0) | \
+ ((mode) << 2) | \
+ ((mode) << 4) | \
+ ((mode) << 6)

BUT SEE:

do {} while (0) advice is over-stated in a few situations:

The more obvious case is macros, like MODULE_PARM_DESC, invoked at
file-scope, where C disallows code (it must be in functions). See
$exceptions if you have one to add by name.

More troublesome is declarative macros used at top of new scope,
like DECLARE_PER_CPU. These might just compile with a do-while-0
wrapper, but would be incorrect. Most of these are handled by
detecting struct,union,etc declaration primitives in $exceptions.

Theres also macros called inside an if (block), which "return" an
expression. These cannot do-while, and need a ({}) wrapper.

Enjoy this qualification while we work to improve our heuristics.

WARNING: please, no spaces at the start of a line
#135: FILE: drivers/leds/leds-as3668.c:55:
+ int ret;$

WARNING: please, no spaces at the start of a line
#136: FILE: drivers/leds/leds-as3668.c:56:
+ u8 channel_modes;$

WARNING: please, no spaces at the start of a line
#138: FILE: drivers/leds/leds-as3668.c:58:
+ ret = i2c_smbus_read_byte_data(led->chip->client, AS3668_CURR_MODE_REG);$

WARNING: please, no spaces at the start of a line
#139: FILE: drivers/leds/leds-as3668.c:59:
+ if (ret < 0) {$

ERROR: code indent should use tabs where possible
#140: FILE: drivers/leds/leds-as3668.c:60:
+ dev_err(led->cdev.dev, "failed to read channel modes\n");$

WARNING: please, no spaces at the start of a line
#140: FILE: drivers/leds/leds-as3668.c:60:
+ dev_err(led->cdev.dev, "failed to read channel modes\n");$

ERROR: code indent should use tabs where possible
#141: FILE: drivers/leds/leds-as3668.c:61:
+ return ret;$

WARNING: please, no spaces at the start of a line
#141: FILE: drivers/leds/leds-as3668.c:61:
+ return ret;$

WARNING: please, no spaces at the start of a line
#142: FILE: drivers/leds/leds-as3668.c:62:
+ }$

WARNING: please, no spaces at the start of a line
#143: FILE: drivers/leds/leds-as3668.c:63:
+ channel_modes = (u8)ret;$

WARNING: please, no spaces at the start of a line
#145: FILE: drivers/leds/leds-as3668.c:65:
+ channel_modes &= ~led->mode_mask;$

WARNING: please, no spaces at the start of a line
#146: FILE: drivers/leds/leds-as3668.c:66:
+ channel_modes |= led->mode_mask & (AS3668_CURR_MODE_PACK(mode));$

WARNING: please, no spaces at the start of a line
#148: FILE: drivers/leds/leds-as3668.c:68:
+ return i2c_smbus_write_byte_data(led->chip->client, AS3668_CURR_MODE_REG, channel_modes);$

WARNING: line length of 104 exceeds 100 columns
#247: FILE: drivers/leds/leds-as3668.c:167:
+ return dev_err_probe(&client->dev, -EIO, "failed to set zero initial current levels\n");

WARNING: DT compatible string "ams,as3668" appears un-documented -- check ./Documentation/devicetree/bindings/
#264: FILE: drivers/leds/leds-as3668.c:184:
+ { .compatible = "ams,as3668" },

total: 3 errors, 13 warnings, 235 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.

NOTE: Whitespace errors detected.
You may wish to use scripts/cleanpatch or scripts/cleanfile

"[PATCH v13 2/2] leds: as3668: Driver for the ams Osram 4-channel" has style problems, please review.

NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

--
Lee Jones [李琼斯]