From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomi Valkeinen Date: Tue, 25 Aug 2015 15:41:17 +0000 Subject: Re: [PATCH 3/3] devicetree: Add led-backlight binding Message-Id: <55DC8C9D.4050007@ti.com> MIME-Version: 1 Content-Type: multipart/mixed; boundary="wmGoInHECcIXbDmCg9TGr7A3l5A0et3si" List-Id: References: <1440502442-19531-1-git-send-email-tomi.valkeinen@ti.com> <1440502442-19531-4-git-send-email-tomi.valkeinen@ti.com> <55DC700C.4030802@samsung.com> In-Reply-To: <55DC700C.4030802@samsung.com> To: Jacek Anaszewski Cc: Jingoo Han , Lee Jones , linux-leds@vger.kernel.org, linux-fbdev@vger.kernel.org, Andrew Lunn --wmGoInHECcIXbDmCg9TGr7A3l5A0et3si Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable On 25/08/15 16:39, Jacek Anaszewski wrote: >> +Example: >> + >> + backlight { >> + compatible =3D "led-backlight"; >> + leds =3D <&backlight_led>; >> + >> + brightness-levels =3D <0 4 8 16 32 64 128 255>; >=20 > brightness level is not a suitable unit for describing LED brightness > in a Device Tree, as it is not a physical unit. We have led-max-microam= p > property for this, expressed in microamperes, please refer to [0] from > linux-next. Hmm, ok, but what should the driver do with microamperes? As far as I see, "enum led_brightness" (which is between 0-255) is used to set the brightness to LEDs. I don't see any function accepting microamperes. >> + default-brightness-level =3D <6>; >=20 > This also should be microamperes. This is an index to the above brightness-levels array. It's not LED brightness, but backlight brightness, between 0 and ARRAY_SIZE(brightness-levels) - 1. Tomi --wmGoInHECcIXbDmCg9TGr7A3l5A0et3si Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJV3IydAAoJEPo9qoy8lh71QBsQAKKTPMb6bZDkWX8JJvKAF0Nq bE3OalrC12ueYFByGTPWTdsq+FbUiidEvsOFqgnDQzFs4/U9CBF98cFuFtrzNyTi qBYJv+WXaaxYSy2TGEvR1E6TZnodQ+12vMgJdNbCxf55c+18ive0V5WeaanesrUt eWSqCsRteZX6QppDStP028lRpxXm2NsypD8u9RHWXFp7tsuewhnFY2WpzD43lwCs iIYofWJnwPWQo80Kd0xx3bvL07b9kqdcEgNqd0aCiMIteSR9QxUOKvAnXlYChm9c bvFMbtigS0TqFLaAbDkVrmxj8szoCvYZJtqKvKYarYPa9XhtyH/FnID16jenGpoP v7W4OOLZTXesCcWgl1IOf0eBcYdbMJz9029kgLcVgC4Ua//9O+h2ZFR4gxpjImDS duurhEut8SbhsrgZ0mmvEhgiDqSh9h7pNDXys9IYSxy6RVePX/mttwHiHH8b42ba KejCBLImpTUbUWe3q3qnixl3b2W5tycFqKoccRV8fVoDvIIXNuhwcB74mboEF+hE 0VE9fiZ4N4uG7vafSmrDeAkndoT3ykgUiVVYal9Ps5Q8UiKFw4whapiMopa/D2uU g5hdd6sfaojvgOxpjy8wuVbo3sDx9LG3b/fbbk7nmU5PU4dtM8EkjXmlaeVZ9Kkl KNbeVCV5xYHCipze6Ymh =7pMF -----END PGP SIGNATURE----- --wmGoInHECcIXbDmCg9TGr7A3l5A0et3si--