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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 DAB1BC3A5A5 for ; Thu, 5 Sep 2019 03:57:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A777C20820 for ; Thu, 5 Sep 2019 03:57:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=aj.id.au header.i=@aj.id.au header.b="IoF9PQ1R"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="RwBU5Huf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730694AbfIED5C (ORCPT ); Wed, 4 Sep 2019 23:57:02 -0400 Received: from out2-smtp.messagingengine.com ([66.111.4.26]:49867 "EHLO out2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727544AbfIED5B (ORCPT ); Wed, 4 Sep 2019 23:57:01 -0400 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 814F92224B; Wed, 4 Sep 2019 23:57:00 -0400 (EDT) Received: from imap2 ([10.202.2.52]) by compute4.internal (MEProxy); Wed, 04 Sep 2019 23:57:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aj.id.au; h= mime-version:message-id:in-reply-to:references:date:from:to:cc :subject:content-type; s=fm3; bh=+V9xRJ/1HYR/6pMO/bSb1yTgfA8crQE LD2nMcJY5P7A=; b=IoF9PQ1RkDCys0xkz+lZRQguCSRh7slGKu5KZtp+1LyW8i/ a7DFk4a3k8BtOhf3yMfLLSfil2OCs40k4cHV+u5IYo8s+WGQ++7d/oyGVAlENucA o71Auw5Mq6LTZ4NPnB9KetCTEFIwBqqduKdrSUKdEj10plt+Qe/CSfJm2wQKTqFO UXL16wcbbdvN3cRvfC/hq7znM/QPAVG2mlvUDyxSuT7G+ISWgdmGu77tHkwPUJCS C4yiZuq5kYTiRqD/hznCSwgGFs5pDopWR/QAhsGJgkCt/Ircho/SU/Dpcuv3h9S9 /ycjiFlSF9aZuJtaGI9R3k91VLlCXg9JtgMEIJw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=+V9xRJ /1HYR/6pMO/bSb1yTgfA8crQELD2nMcJY5P7A=; b=RwBU5HufEwtLr7hmn5hFM8 3jFoeaJ/dg+xVlYvI5fqMNShQ4Eu8zM3oi5mz+xKKP5pCsHH0uH3xEymJCvQQkoh 44rcJkgW5aPTeOpKzS0BDRH3NeTbmcAzKcziFoieNzQ+6XuDixV9yKRHgD8HWUj1 KNfzO3/2KvcY7cOFI+c4y7Yb4iYMuuNRoY2V9Me4HuiMLF5j0NU0+7H3gB/tX9Ay pJC5rI2R8fr6Jd/nzv2A18/fK0IMaOfj6+7jLKCgmmvznh1mhjUbOKCGgUZkFFpR 0NVPf0lro9lxurIyhhsCXIdc8Mif6W5v4l+a8pV62PILCB2SJbJt+SZsu5xuQFng == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduvddrudejiedgjeeiucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvffutgesthdtredtreertdenucfhrhhomhepfdetnhgu rhgvficulfgvfhhfvghrhidfuceorghnughrvgifsegrjhdrihgurdgruheqnecurfgrrh grmhepmhgrihhlfhhrohhmpegrnhgurhgvfiesrghjrdhiugdrrghunecuvehluhhsthgv rhfuihiivgeptd X-ME-Proxy: Received: by mailuser.nyi.internal (Postfix, from userid 501) id E2964E00A3; Wed, 4 Sep 2019 23:56:58 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.1.7-186-gf4cb3c3-fmstable-20190904v1 Mime-Version: 1.0 Message-Id: <40601711-5fcf-40a0-bfc2-ae5043948a41@www.fastmail.com> In-Reply-To: <20190905011732.16059-1-rashmica.g@gmail.com> References: <20190905011732.16059-1-rashmica.g@gmail.com> Date: Thu, 05 Sep 2019 13:27:23 +0930 From: "Andrew Jeffery" To: "Rashmica Gupta" , "Linus Walleij" Cc: "Bartosz Golaszewski" , "Joel Stanley" , linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/4] gpio: Add in ast2600 details to Aspeed driver Content-Type: text/plain Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Thu, 5 Sep 2019, at 10:47, Rashmica Gupta wrote: > The ast2600 is a new generation of SoC from ASPEED. Similarly to the > ast2400 and ast2500, it has a GPIO controller for it's 3.6V GPIO pins. > Additionally, it has a GPIO controller for 36 1.8V GPIO pins. These > voltages are fixed and cannot be configured via pinconf, so we need two > separate drivers for them. Working backwards, we don't really have multiple drivers, just different configurations for the same driver. So I think this should be reworded. Also it's not really the voltage differences that are driving the different configurations but rather that there are two separate sets of registers in the 2600 with overlapping bank names (they happen to be split into 3.3V and 1.8V groups). The key point being that there aren't just more GPIO registers tacked on the end of the original 3.3V group. > > Signed-off-by: Rashmica Gupta > --- > drivers/gpio/gpio-aspeed.c | 30 ++++++++++++++++++++++++++++-- > 1 file changed, 28 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c > index 16c6eaf70857..4723b8780a8c 100644 > --- a/drivers/gpio/gpio-aspeed.c > +++ b/drivers/gpio/gpio-aspeed.c > @@ -662,12 +662,14 @@ static void aspeed_gpio_irq_handler(struct irq_desc *desc) > struct gpio_chip *gc = irq_desc_get_handler_data(desc); > struct irq_chip *ic = irq_desc_get_chip(desc); > struct aspeed_gpio *data = gpiochip_get_data(gc); > - unsigned int i, p, girq; > + unsigned int i, p, girq, banks; > unsigned long reg; > + struct aspeed_gpio *gpio = gpiochip_get_data(gc); > > chained_irq_enter(ic, desc); > > - for (i = 0; i < ARRAY_SIZE(aspeed_gpio_banks); i++) { > + banks = DIV_ROUND_UP(gpio->config->nr_gpios, 32); > + for (i = 0; i < banks; i++) { > const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i]; > > reg = ioread32(bank_reg(data, bank, reg_irq_status)); > @@ -1108,9 +1110,33 @@ static const struct aspeed_gpio_config ast2500_config = > /* 232 for simplicity, actual number is 228 (4-GPIO hole in GPIOAB) */ > { .nr_gpios = 232, .props = ast2500_bank_props, }; > > +static const struct aspeed_bank_props ast2600_bank_props[] = { > + /* input output */ > + {5, 0xffffffff, 0x0000ffff}, /* U/V/W/X */ > + {6, 0xffff0000, 0x0fff0000}, /* Y/Z */ > + { }, > +}; > + > +static const struct aspeed_gpio_config ast2600_config = > + /* 208 3.6V GPIOs */ > + { .nr_gpios = 208, .props = ast2600_bank_props, }; > + > +static const struct aspeed_bank_props ast2600_1_8v_bank_props[] = { > + /* input output */ > + {1, 0x0000000f, 0x0000000f}, /* E */ If there are 36 GPIOs then this configuration is suggesting that all of them are capable of input and output. A handy observation here is that the first 36 GPIOs of the 3.3V GPIO controller in the 2600 also have both capabilities, so we can re-use the 3.3V configuration if we can limit the number of GPIOs somehow. The devicetree binding already describes an `ngpios` property so perhaps we could make use of this to use the same properties struct instance for both controllers in the 2600: Require that the property be present for 2600- compatible devicetree nodes and test for its presence in probe(), then fall back to the hard-coded value in the config struct if it is not (this keeps devicetree compatibility for the 2400 and 2500 drivers). This way we can eliminate the aspeed,ast2600-1-8v-gpio compatible string below (we just use aspeed,ast2600-gpio for both controllers). Thoughts? Andrew > + { }, > +}; > + > +static const struct aspeed_gpio_config ast2600_1_8v_config = > + /* 36 1.8V GPIOs */ > + { .nr_gpios = 36, .props = ast2600_1_8v_bank_props, }; > + > static const struct of_device_id aspeed_gpio_of_table[] = { > { .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, }, > { .compatible = "aspeed,ast2500-gpio", .data = &ast2500_config, }, > + { .compatible = "aspeed,ast2600-gpio", .data = &ast2600_config, }, > + { .compatible = "aspeed,ast2600-1-8v-gpio", > + .data = &ast2600_1_8v_config, }, > {} > }; > MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table); > -- > 2.20.1 > >