From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pd0-f170.google.com ([209.85.192.170]:62281 "EHLO mail-pd0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751095AbaHPGNB (ORCPT ); Sat, 16 Aug 2014 02:13:01 -0400 Received: by mail-pd0-f170.google.com with SMTP id g10so4497249pdj.1 for ; Fri, 15 Aug 2014 23:12:32 -0700 (PDT) Date: Sat, 16 Aug 2014 14:12:32 +0800 From: "nibble.max" To: "Antti Palosaari" Cc: "linux-media" , "olli.salonen" Subject: [PATCH] m88ts2022: fix high symbol rate transponders missing on 32bit platform. Message-ID: <201408161412275930052@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: The current m88ts2022 driver will miss the following high symbol rate transponders on Telstar 18 138.0. 12385 H 43200, 12690 H 43200, 12538 V 41250... the code for f_3db_hz will overflow for the high symbol rate. for example, symbol rate=41250 KS/s symbol_rate * 135UL = 5568750000(1 4BEC 61B0), the value is larger than unsigned int on 32bit platform. that makes the wrong result. Exchanging the div and mul position fixs it. Signed-off-by: Nibble Max --- drivers/media/tuners/m88ts2022.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/tuners/m88ts2022.c b/drivers/media/tuners/m88ts2022.c index 40c42de..65c8acc 100644 --- a/drivers/media/tuners/m88ts2022.c +++ b/drivers/media/tuners/m88ts2022.c @@ -314,7 +314,7 @@ static int m88ts2022_set_params(struct dvb_frontend *fe) div_min = gdiv28 * 78 / 100; div_max = clamp_val(div_max, 0U, 63U); - f_3db_hz = c->symbol_rate * 135UL / 200UL; + f_3db_hz = (c->symbol_rate / 200UL) * 135UL; f_3db_hz += 2000000U + (frequency_offset_khz * 1000U); f_3db_hz = clamp(f_3db_hz, 7000000U, 40000000U); -- 1.9.1