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 2E719C43334 for ; Wed, 15 Jun 2022 19:38:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349684AbiFOTi4 (ORCPT ); Wed, 15 Jun 2022 15:38:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244636AbiFOTiz (ORCPT ); Wed, 15 Jun 2022 15:38:55 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04DB13BBE6; Wed, 15 Jun 2022 12:38:54 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A7BFFB81F00; Wed, 15 Jun 2022 19:38:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0171C3411E; Wed, 15 Jun 2022 19:38:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655321932; bh=8r4cD4LYkuropBC5jhH9yIfHJXDhGCTZ6tTZPJiVzmY=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=AG5O5ndr4bq6IRx1S/TbkW5g7CAx9ZeCS2dbafIRidLMw/X2lCtA7wcW0MD+6mkGM ok3LJ8OuUlxbO4rP+eHtohbeKSIQeOSo4VtH8p2jVjcer6vg2fl3TyZ+HdI+JeW7YM 7En4ewQILS0yE9Dq3LD2SeumP5IZyjqDoRWKQ+g3F9ytWuXZ3Ghds08ATjP2MH7o3e efZTbxuBSbvSyocvX1BQB9XnzmkdeNHcRuWMPYwWRACqqfENO4NT/c9BJW2LJuDDu7 XuccQmp5pX1DKDltz7Xvp4yFhtJoI1Uy5gJiWKfxCa7w9xY1Bfgh/o8tPWmEfwPDjL 7r3xb3SEbfhHw== Message-ID: <4fd5ed33-a92e-71ed-b02c-da6f7c482c0a@kernel.org> Date: Wed, 15 Jun 2022 14:38:47 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCHv4 1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms Content-Language: en-US To: jarkko.nikula@linux.intel.com Cc: andriy.shevchenko@linux.intel.com, mika.westerberg@linux.intel.com, robh+dt@kernel.org, krzk+dt@kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org References: <20220615191214.826879-1-dinguyen@kernel.org> From: Dinh Nguyen In-Reply-To: <20220615191214.826879-1-dinguyen@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On 6/15/22 14:12, Dinh Nguyen wrote: > The I2C pins on the SoCFPGA platforms do not go through a GPIO module, > thus cannot be recovered by the default method of by doing a GPIO access. > Only a reset of the I2C IP block can a recovery be successful. > > The assignment of the recover_bus needs to get done before the call to > devm_gpiod_get_optional(), otherwise, the assignment is not taking place > because of an error after returning from devm_gpiod_get_optional(). > > Signed-off-by: Dinh Nguyen > --- > v4: re-arrange code per Andy Shevchenko's recommendation > v3: simplify the function > update commit message > v2: remove change to MODEL_MASK > s/i2c_custom_scl_recovery/i2c_socfpga_scl_recovery > --- > drivers/i2c/busses/i2c-designware-core.h | 1 + > drivers/i2c/busses/i2c-designware-master.c | 50 ++++++++++++++++++--- > drivers/i2c/busses/i2c-designware-platdrv.c | 1 + > 3 files changed, 46 insertions(+), 6 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h > index 70b80e710990..7b22ec1d6a96 100644 > --- a/drivers/i2c/busses/i2c-designware-core.h > +++ b/drivers/i2c/busses/i2c-designware-core.h > @@ -303,6 +303,7 @@ struct dw_i2c_dev { > #define MODEL_MSCC_OCELOT BIT(8) > #define MODEL_BAIKAL_BT1 BIT(9) > #define MODEL_AMD_NAVI_GPU BIT(10) > +#define MODEL_SOCFPGA BIT(11) > #define MODEL_MASK GENMASK(11, 8) > > /* > diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c > index 44a94b225ed8..6b75a08a1c1f 100644 > --- a/drivers/i2c/busses/i2c-designware-master.c > +++ b/drivers/i2c/busses/i2c-designware-master.c > @@ -813,10 +813,26 @@ static void i2c_dw_unprepare_recovery(struct i2c_adapter *adap) > i2c_dw_init_master(dev); > } > > -static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) > +static int i2c_socfpga_scl_recovery(struct i2c_adapter *adap) > +{ > + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; > + > + bri->prepare_recovery(adap); > + bri->unprepare_recovery(adap); > + > + return 0; > +} > + > +static int i2c_dw_init_socfpga_recovery_info(struct dw_i2c_dev *dev, > + struct i2c_bus_recovery_info *rinfo) > +{ > + rinfo->recover_bus = i2c_socfpga_scl_recovery; > + return 1; > +} > + > +static int i2c_dw_init_generic_recovery_info(struct dw_i2c_dev *dev, > + struct i2c_bus_recovery_info *rinfo) > { > - struct i2c_bus_recovery_info *rinfo = &dev->rinfo; > - struct i2c_adapter *adap = &dev->adapter; > struct gpio_desc *gpio; > > gpio = devm_gpiod_get_optional(dev->dev, "scl", GPIOD_OUT_HIGH); > @@ -831,16 +847,38 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) > rinfo->sda_gpiod = gpio; > > rinfo->recover_bus = i2c_generic_scl_recovery; > - rinfo->prepare_recovery = i2c_dw_prepare_recovery; > - rinfo->unprepare_recovery = i2c_dw_unprepare_recovery; > - adap->bus_recovery_info = rinfo; > > dev_info(dev->dev, "running with gpio recovery mode! scl%s", > rinfo->sda_gpiod ? ",sda" : ""); > > + return 1; > +} > + > +static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) > +{ > + struct i2c_bus_recovery_info *rinfo = &dev->rinfo; > + struct i2c_adapter *adap = &dev->adapter; > + int ret; > + > + switch (dev->flags & MODEL_MASK) { > + case MODEL_SOCFPGA: > + ret = i2c_dw_init_socfpga_recovery_info(dev, rinfo); > + break; > + default: > + ret = i2c_dw_init_generic_recovery_info(dev, rinfo); > + break; > + } > + if (ret <= 0) > + return ret; > + > + rinfo->prepare_recovery = i2c_dw_prepare_recovery; > + rinfo->unprepare_recovery = i2c_dw_unprepare_recovery; > + adap->bus_recovery_info = rinfo; > + > return 0; > } > > + Sorry for this stray newline, let me if you need me to send a v5? > static int amd_i2c_adap_quirk(struct dw_i2c_dev *dev) > { > struct i2c_adapter *adap = &dev->adapter; > diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c > index 70ade5306e45..b33e015e6732 100644 > --- a/drivers/i2c/busses/i2c-designware-platdrv.c > +++ b/drivers/i2c/busses/i2c-designware-platdrv.c > @@ -153,6 +153,7 @@ static const struct of_device_id dw_i2c_of_match[] = { > { .compatible = "snps,designware-i2c", }, > { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT }, > { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 }, > + { .compatible = "intel,socfpga-i2c", .data = (void *)MODEL_SOCFPGA }, > {}, > }; > MODULE_DEVICE_TABLE(of, dw_i2c_of_match);