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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 3F397C433E1 for ; Wed, 26 Aug 2020 08:55:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F02732071E for ; Wed, 26 Aug 2020 08:55:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598432149; bh=QMndYZ6vu/NhmekefXUyl5NW9B3dLtTbytao7DwlYdE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=WFDd9WsjOQ9hEYIbhF92UgQ4VrgXqb2z9XqoMIUsr9K2AkzLKCwob9TlvWAUSfIvF jhc4ccCBpsuvl32I/YvOUega6pjXnZ7brJdBihpY4SiHb2fEyOZkqhR1uI/bbdlUrM MiRntbb5VCCUCmQBncpCQuqntfE3ANwvfEdKNlF0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727917AbgHZIzs (ORCPT ); Wed, 26 Aug 2020 04:55:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:42360 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727793AbgHZIzq (ORCPT ); Wed, 26 Aug 2020 04:55:46 -0400 Received: from localhost (unknown [122.171.38.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C5066206EB; Wed, 26 Aug 2020 08:55:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598432144; bh=QMndYZ6vu/NhmekefXUyl5NW9B3dLtTbytao7DwlYdE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Mpr1CDb24jgZnMbRof/qhYO3PbfKOejO9E4DC6d1PAnQLN2uuJx/07a2WDSuDCPM/ xwxsDEcVO1R3pHinMT5eu/k1Ro+oC8vVB5Pz8998oKwTX4oEqcbik95K+LkR973hOZ L/Or+IzLFPFZpGNkpsqvYIG/fiVXfW9qpea5uBX0= Date: Wed, 26 Aug 2020 14:25:40 +0530 From: Vinod Koul To: Pierre-Louis Bossart Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, tiwai@suse.de, broonie@kernel.org, gregkh@linuxfoundation.org, jank@cadence.com, srinivas.kandagatla@linaro.org, slawomir.blauciak@intel.com, Bard liao , Rander Wang , Ranjani Sridharan , Hui Wang , Guennadi Liakhovetski , Kai Vehmanen , Sanyog Kale Subject: Re: [PATCH 3/4] soundwire: SDCA: add helper macro to access controls Message-ID: <20200826085540.GY2639@vkoul-mobl> References: <20200825171656.75836-1-pierre-louis.bossart@linux.intel.com> <20200825171656.75836-4-pierre-louis.bossart@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200825171656.75836-4-pierre-louis.bossart@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25-08-20, 12:16, Pierre-Louis Bossart wrote: > The upcoming SDCA (SoundWire Device Class Audio) specification defines > a hierarchical encoding to interface with Class-defined capabilities. > > The specification is not yet accessible to the general public but this > information is released with explicit permission from the MIPI Board > to avoid delays with SDCA support on Linux platforms. > > A block of 64 MBytes of register addresses are allocated to SDCA > controls, starting at address 0x40000000. The 26 LSBs which identify > individual controls are set based on the following variables: > > - Function Number. An SCDA device can be split in up to 8 independent > Functions. Each of these Functions is described in the SDCA > specification, e.g. Smart Amplifier, Smart Microphone, Simple > Microphone, Jack codec, HID, etc. > > - Entity Number. Within each Function, an Entity is an identifiable > block. Up to 127 Entities are connected in a pre-defined > graph (similar to USB), with Entity0 reserved for Function-level > configurations. In contrast to USB, the SDCA spec pre-defines > Function Types, topologies, and allowed options, i.e. the degree of > freedom is not unlimited to limit the possibility of errors in > descriptors leading to software quirks. > > - Control Selector. Within each Entity, the SDCA specification defines > 48 controls such as Mute, Gain, AGC, etc, and 16 implementation > defined ones. Some Control Selectors might be used for low-level > platform setup, and other exposed to applications and users. Note > that the same Control Selector capability, e.g. Latency control, > might be located at different offsets in different entities, the > Control Selector mapping is Entity-specific. > > - Control Number. Some Control Selectors allow channel-specific values > to be set, with up to 64 channels allowed. This is mostly used for > volume control. > > - Current/Next values. Some Control Selectors are > 'Dual-Ranked'. Software may either update the Current value directly > for immediate effect. Alternatively, software may write into the > 'Next' values and update the SoundWire 1.2 'Commit Groups' register > to copy 'Next' values into 'Current' ones in a synchronized > manner. This is different from bank switching which is typically > used to change the bus configuration only. > > - MBQ. the Multi-Byte Quantity bit is used to provide atomic updates > when accessing more that one byte, for example a 16-bit volume > control would be updated consistently, the intermediate values > mixing old MSB with new LSB are not applied. > > These 6 parameters are used to build a 32-bit address to access the > desired Controls. Because of address range, paging is required, but > the most often used parameter values are placed in the lower 16 bits > of the address. This helps to keep the paging registers constant while > updating Controls for a specific Device/Function. > > Reviewed-by: Rander Wang > Reviewed-by: Guennadi Liakhovetski > Reviewed-by: Kai Vehmanen > Signed-off-by: Pierre-Louis Bossart > --- > include/linux/soundwire/sdw_registers.h | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/include/linux/soundwire/sdw_registers.h b/include/linux/soundwire/sdw_registers.h > index 5d3c271af7d1..906dadda7387 100644 > --- a/include/linux/soundwire/sdw_registers.h > +++ b/include/linux/soundwire/sdw_registers.h > @@ -305,4 +305,17 @@ > #define SDW_CASC_PORT_MASK_INTSTAT3 1 > #define SDW_CASC_PORT_REG_OFFSET_INTSTAT3 2 > > +/* v1.2 device - SDCA address mapping */ Can you please add description of bits used by each field here, something like we have done for DevId > +#define SDW_SDCA_CTL(fun, ent, ctl, ch) (BIT(30) | \ > + (((fun) & 0x7) << 22) | \ > + (((ent) & 0x40) << 15) | \ > + (((ent) & 0x3f) << 7) | \ > + (((ctl) & 0x30) << 15) | \ > + (((ctl) & 0x0f) << 3) | \ > + (((ch) & 0x38) << 12) | \ > + ((ch) & 0x07)) GENMASK() for the bitmaps here please. Also it would look very neat by using FIELD_PREP() here, you can skip the bit shifts and they would be done by FIELD_PREP() for you. > -- > 2.25.1 -- ~Vinod