From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomi Valkeinen Date: Fri, 29 Jan 2016 11:55:06 +0000 Subject: Re: [PATCH] fbdev: ssd1307fb: Fix chargepump setting Message-Id: <56AB531A.2020805@ti.com> MIME-Version: 1 Content-Type: multipart/mixed; boundary="P42GTvwSvsLgQW0fNLKuTr0cGFkL7ELde" List-Id: References: <1447337257-31232-1-git-send-email-julian@jusst.de> In-Reply-To: <1447337257-31232-1-git-send-email-julian@jusst.de> To: linux-fbdev@vger.kernel.org --P42GTvwSvsLgQW0fNLKuTr0cGFkL7ELde Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 18/01/16 22:20, Julian Scheel wrote: > On 15.11.15 14:36, Julian Scheel wrote: >> The charge pump setting must have bit D4 set all time according to the= >> SSD1306 >> App Note. Instead of doing an logical and off shifted setting bit with= >> 0x14 it >> must be an logical or with 0x10 to ensure D4 is set. The code change looks ok, but I can't quite decipher the commit description. "an logical and off shifted setting bit with 0x14"? >> Signed-off-by: Julian Scheel >> --- >> drivers/video/fbdev/ssd1307fb.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/video/fbdev/ssd1307fb.c >> b/drivers/video/fbdev/ssd1307fb.c >> index 1611215..5965a9b 100644 >> --- a/drivers/video/fbdev/ssd1307fb.c >> +++ b/drivers/video/fbdev/ssd1307fb.c >> @@ -389,7 +389,7 @@ static int ssd1307fb_init(struct ssd1307fb_par *pa= r) >> return ret; >> >> ret =3D ssd1307fb_write_cmd(par->client, >> - (par->device_info->need_chargepump & 0x1 << 2) & 0x14); >> + 0x10 | ((par->device_info->need_chargepump & 0x01) << 2)); I presume 'need_chargepump' is really supposed to be a bool, instead of int. And if it's really bool, something like this makes it more readable to me: BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0) Tomi --P42GTvwSvsLgQW0fNLKuTr0cGFkL7ELde 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 iQIcBAEBCAAGBQJWq1MaAAoJEPo9qoy8lh71KSEP/11wS48Ml6wcmOntW83pGsiD B6s/thiuIXJKS3i8/E9evAQts/D8DeS1bWyeHVpbW1hBeqzo+l0JuXEwGqTQT9Xu 3K1EP7x12EWwkKxwgvY6rSpmXAHQ1I+QZ6DDx8iWvyclMBKRVZIUHXbTUCbMW4pL yAXWVNk+lOpBMaRV5871LZdUSjPFsfY+vaAekNWtNEhN2bwRU1ILqs6kNCxbvv0x qjtw/xMGOOSQcT4oxhD6EwJ2m/LtxfITJadN1RMpcPU0bsss6Br+Ei+wXp2t873f Q7nJGmVcPvtRQWxWKSsd9CUhzBZFR+So52Kiv16sPL+akArW2tHP5ilEaEPMGMmw QNGyK04OdQrBjjl7HBqbm1SMTOU0qU+mveMAjLf3ofEC5a4PP4/FimYZamCGdwVY ctYPo1FzVKXqQ+VfWaiWR9OXIilCWvtbFJkYYBzWDd/Q6vkPDGTwNJpDqVI4Z0jP reRiMrYe4NRNxpOSIjNKPFNmStEmfC3jfInwCes3eucMQEBMXJmF40y+aod642vR KyBDhgnFz8KxYTvQnhVlmM2RoVUF3u8ylxhfo0KHYwPcSNgQVh2YxGYuBLOUcUYC jkbvQBN/bFXCy1cBVZUQcDVbO44s6+EGb3kKUymJCDvyN0aIEh8aOMwO0ONC5bDf 6uxejJIbosqjsmFKPGmv =22rW -----END PGP SIGNATURE----- --P42GTvwSvsLgQW0fNLKuTr0cGFkL7ELde--