From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 874D61EA7F for ; Wed, 11 Oct 2023 11:58:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="PCMwqTGT" Received: from mail-yw1-x112b.google.com (mail-yw1-x112b.google.com [IPv6:2607:f8b0:4864:20::112b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92DA6B0 for ; Wed, 11 Oct 2023 04:58:47 -0700 (PDT) Received: by mail-yw1-x112b.google.com with SMTP id 00721157ae682-5a7b3d33663so29567167b3.3 for ; Wed, 11 Oct 2023 04:58:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1697025527; x=1697630327; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=dcZX87bVMqxb05uB6AITFLlBPsFoCe5WSTHnOrtHLWk=; b=PCMwqTGTQSOdLQ5tzB4LsBush06zF9Zytml2uVqQkmENIq1Anj3QU+O/JMLl5UsA9O CRbAFcOwQT0RPu+6/7RLcQ5TrfwJHGs7VdDD14IaWsOnPwYE+OANIc7ibaSyn98ltawr pkEfoE/+K09sQdCV0je8/kBBvH6sZ1c0sumoDBXIjZrrGQKUFZUmXKqlAsnMucWux04+ ALpHIOj69o21eamlYt6rE013p0AM/etYpPlkAazk09YPXC3g9A0VEmIcmKhwYsFDTd4d Sff5IkEAnKB6JpOir1RF++S0ZeHLahrAg7dCONmokRf0iwnYS2RqZb0VTdin48DSn+80 pHQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697025527; x=1697630327; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=dcZX87bVMqxb05uB6AITFLlBPsFoCe5WSTHnOrtHLWk=; b=aAN1NrkSwBr1+Gu/yc4dIL4mfLGw33ClUEzxHChoM05fpTr4c39nPOdn2Yb96xtKKT w9k1D1CxycVAlmAubQ0QOGdWM9u3WLrSK356PywH7BA3w5OGuTLyiIFhwBg8sM41fLJk /RQdMSNTq94MN0MQisqGc0AM1UnWSPWIVl2fj2Z/4LkxUaag03hbZsjUQUW885HBKCNj NlPQaDKOrCK7hFmke9pK7QiqwHJcYy7Sd8sgcuiH32LBjvAVZFuOLa6xtvyyvxPettSR pSEZT1M6jE4NhsGkKKWTCeasw5FzhN+2M/hR1tOqIdJlD9XzULk2chPDYVzQFtLR9DvK AIsw== X-Gm-Message-State: AOJu0Yx4f+Zc9ZJRXHqjie51QpHjx6oVMi4XGanRgSNWayEQtUcDNtu3 BTPdF3ixDziaiz3EC4ziB+0GGeUkBvLbxxponCkORQ== X-Google-Smtp-Source: AGHT+IEMT7FKO0GU0LYWIJk61ZoZMd77YWiVGpHr+v/XgAesZ5a9ZC1QYGCxEuGoxQsKfMhFwWDDkXPOv2GeSnJqJoE= X-Received: by 2002:a81:5c86:0:b0:59f:4f56:59bc with SMTP id q128-20020a815c86000000b0059f4f5659bcmr22662562ywb.42.1697025526803; Wed, 11 Oct 2023 04:58:46 -0700 (PDT) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20231010224928.2296997-1-peter.griffin@linaro.org> <20231010224928.2296997-9-peter.griffin@linaro.org> <2023101111-banknote-satin-1f77@gregkh> In-Reply-To: <2023101111-banknote-satin-1f77@gregkh> From: Linus Walleij Date: Wed, 11 Oct 2023 13:58:35 +0200 Message-ID: Subject: Re: [PATCH v2 08/20] dt-bindings: serial: samsung: Add google-gs101-uart compatible To: Greg KH Cc: Peter Griffin , robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, mturquette@baylibre.com, conor+dt@kernel.org, sboyd@kernel.org, tomasz.figa@gmail.com, s.nawrocki@samsung.com, wim@linux-watchdog.org, linux@roeck-us.net, catalin.marinas@arm.com, will@kernel.org, arnd@arndb.de, olof@lixom.net, cw00.choi@samsung.com, tudor.ambarus@linaro.org, andre.draszik@linaro.org, semen.protsenko@linaro.org, saravanak@google.com, willmcvicker@google.com, soc@kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-gpio@vger.kernel.org, linux-watchdog@vger.kernel.org, kernel-team@android.com, linux-serial@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Wed, Oct 11, 2023 at 9:48=E2=80=AFAM Greg KH wrote: > > - enum: > > - apple,s5l-uart > > - axis,artpec8-uart > > + - google,gs101-uart > > These shouldn't be needed, just declare the device as the same as what > the chip really is (i.e. a samsung uart), that way no .yaml or kernel > driver changes are needed at all. We strive to have these as unique as possible, as it is a hardware description. It is fine to write drivers in Linux or any other OS just being aware of a "courser" idea of what UART this is, in this case would have looked something like this: compatible =3D "google,gs101-uart", "samsung-uart"; And the driver would be able to match to just the latter string (these are listed in "particularity order"). BUT! The binding authors chose not to go that path, instead they have one unique compatible string per hardware/integration version, essentially per-SoC. So in this case it is just: compatible =3D "google,gs101-uart"; It is kind of impossible to fix now as well, because these bindings are already deployed. So they are like a BIOS: written in stone. It is possible to add dual compatibles for this *and following* variants, but I don't know how Krzysztof feels about that, and as others point out, probably knowledge of the exact SoC is necessary. Yours, Linus Walleij