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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9517FC433F5 for ; Thu, 3 Mar 2022 11:40:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229929AbiCCLlU convert rfc822-to-8bit (ORCPT ); Thu, 3 Mar 2022 06:41:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232404AbiCCLlU (ORCPT ); Thu, 3 Mar 2022 06:41:20 -0500 Received: from gloria.sntech.de (gloria.sntech.de [185.11.138.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83DA2DD97E for ; Thu, 3 Mar 2022 03:40:33 -0800 (PST) Received: from ip5b412258.dynamic.kabel-deutschland.de ([91.65.34.88] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nPjos-0007nY-N4; Thu, 03 Mar 2022 12:40:30 +0100 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Jianqun Xu Cc: linus.walleij@linaro.org, linux-rockchip@lists.infradead.org, linux-gpio@vger.kernel.org, Jianqun Xu Subject: Re: [PATCH 2/2] gpio: rockchip: get pinctrl node from 'gpio-ranges' property Date: Thu, 03 Mar 2022 12:40:30 +0100 Message-ID: <2004737.KQk8vJUODO@diego> In-Reply-To: <20220303062211.1378883-3-jay.xu@rock-chips.com> References: <20220303062211.1378883-1-jay.xu@rock-chips.com> <20220303062211.1378883-3-jay.xu@rock-chips.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Hi Jianqun, Am Donnerstag, 3. März 2022, 07:22:11 CET schrieb Jianqun Xu: > The dt nodes for rockchip soc designes as > > pinctrl: pinctrl { > gpio { > gpio-ranges = <&pinctrl xxx>; > }; > }; > > Currently, we get the pinctrl dt node from parent of gpio, this patch > try to get pinctrl dt node from 'gpio-ranges' property. > > After this patch, the dt nodes possible to be > > gpio { > gpio-ranges = <&pinctrl xxx>; > }; > > pinctrl: pinctrl { > > }; > > then the gpio driver could register as platform device itself, but not > populate from pinctrl driver. The change looks interesting, as it would solve that long-standing design-issue I "created" back in 2013 ;-) . Though you need to keep some things in mind: (1) Such a change should be reflected in the devicetree binding as it involves a different form of nodes and introduces. Looking at the binding description, using gpio-ranges to map to specific pinctrl pins really seems to be a valid use for this. (2) Keep things backwards compatible. Old devicetrees should stay working with new kernel versions A common pattern is to try the new approach and if that fails try the "deprecated" method, which should be nicely doable when looking at the code change below. Heiko > Signed-off-by: Jianqun Xu > --- > drivers/gpio/gpio-rockchip.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c > index 1da0324445cc..46c54dff92db 100644 > --- a/drivers/gpio/gpio-rockchip.c > +++ b/drivers/gpio/gpio-rockchip.c > @@ -690,6 +690,9 @@ rockchip_gpio_find_bank(struct pinctrl_dev *pctldev, int id) > int i, found = 0; > > info = pinctrl_dev_get_drvdata(pctldev); > + if (!info) > + return NULL; > + > bank = info->ctrl->pin_banks; > for (i = 0; i < info->ctrl->nr_banks; i++, bank++) { > if (bank->bank_num == id) { > @@ -705,15 +708,16 @@ static int rockchip_gpio_probe(struct platform_device *pdev) > { > struct device *dev = &pdev->dev; > struct device_node *np = dev->of_node; > - struct device_node *pctlnp = of_get_parent(np); > + struct device_node *pctlnp = NULL; > struct pinctrl_dev *pctldev = NULL; > struct rockchip_pin_bank *bank = NULL; > struct rockchip_pin_output_deferred *cfg; > static int gpio; > int id, ret; > > - if (!np || !pctlnp) > - return -ENODEV; > + pctlnp = of_parse_phandle(np, "gpio-ranges", 0); > + if (!pctlnp) > + pctlnp = of_get_parent(np); > > pctldev = of_pinctrl_get(pctlnp); > if (!pctldev) >