From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73D42C433E2 for ; Thu, 3 Sep 2020 16:45:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5638620716 for ; Thu, 3 Sep 2020 16:45:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728490AbgICQpT (ORCPT ); Thu, 3 Sep 2020 12:45:19 -0400 Received: from smtprelay0252.hostedemail.com ([216.40.44.252]:47136 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728145AbgICQpS (ORCPT ); Thu, 3 Sep 2020 12:45:18 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay05.hostedemail.com (Postfix) with ESMTP id 76A551802926E; Thu, 3 Sep 2020 16:45:15 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: tree80_350539c270ab X-Filterd-Recvd-Size: 3682 Received: from XPS-9350.home (unknown [47.151.133.149]) (Authenticated sender: joe@perches.com) by omf15.hostedemail.com (Postfix) with ESMTPA; Thu, 3 Sep 2020 16:45:13 +0000 (UTC) Message-ID: <6b225c10b6c71ffbc79c236b64dcc83fc33cc21b.camel@perches.com> Subject: Re: [PATCH 2/3] media: Add support for the AM/FM radio chip KT0913 from KT Micro. From: Joe Perches To: Santiago Hormazabal , linux-media@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring , Ezequiel Garcia , Hans Verkuil , Mauro Carvalho Chehab , linux-kernel@vger.kernel.org Date: Thu, 03 Sep 2020 09:45:12 -0700 In-Reply-To: <20200831220601.20794-3-santiagohssl@gmail.com> References: <20200831220601.20794-1-santiagohssl@gmail.com> <20200831220601.20794-3-santiagohssl@gmail.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.36.4-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Mon, 2020-08-31 at 19:06 -0300, Santiago Hormazabal wrote: > This chip requires almost no support components and can used over I2C. > The driver uses the I2C bus and exposes the controls as a V4L2 radio. > Tested with a module that contains this chip (from SZZSJDZ.com, > part number ZJ-801B, even tho the company seems defunct now), and an H2+ > AllWinner SoC running a kernel built off 07d999f of the media_tree. Thanks. style trivia: [] > diff --git a/drivers/media/radio/radio-kt0913.c b/drivers/media/radio/radio-kt0913.c [] > +static const struct reg_sequence kt0913_init_regs_to_defaults[] = { > + /* Standby disabled, volume 0dB */ > + { KT0913_REG_RXCFG, 0x881f }, These might be more legible on single lines, ignoring the 80 column limits. > + /* FM Channel spacing = 50kHz, Right & Left unmuted */ > + { KT0913_REG_SEEK, 0x000b }, etc... [] > +static int __kt0913_set_fm_frequency(struct kt0913_device *radio, > + unsigned int frequency) > +{ > + return regmap_write(radio->regmap, KT0913_REG_TUNE, > + KT0913_TUNE_FMTUNE_ON | (frequency / KT0913_FMCHAN_MUL)); It might be nicer to align multi-line statements to the open parenthesis. [] > +static int __kt0913_set_au_gain(struct kt0913_device *radio, s32 gain) > +{ > + switch (gain) { > + case 6: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_6DB); > + case 3: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_3DB); > + case 0: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_0DB); > + case -3: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_MIN_3DB); > + default: > + return -EINVAL; > + } > +} It's generally more legible to write this with an intermediate variable holding the changed value. It's also most commonly smaller object code. static int __kt0913_set_au_gain(struct kt0913_device *radio, s32 gain) { int val; switch (gain) { case 6: val = KT0913_AMSYSCFG_AU_GAIN_6DB; break; case 3: val = KT0913_AMSYSCFG_AU_GAIN_3DB; break; case 0: val = KT0913_AMSYSCFG_AU_GAIN_0DB; break; case -3: val = KT0913_AMSYSCFG_AU_GAIN_MIN_3DB; break; default: return -EINVAL; } return regmap_update_bits(radio->regmap, KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, val); }