From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x225cnhZke5VTFmvmMzdGDRjlaO+oKQB3yOK2M0V6/IoZZf4mgPxsmzv3uygCWjMRIkO2QzH4 ARC-Seal: i=1; a=rsa-sha256; t=1518552796; cv=none; d=google.com; s=arc-20160816; b=dxBtWRUowH8geXkCVIOA3LnC0aL9V3vKUCv0cszLY9JB7f2/OZjnK+I3kShA7Psn6t tOVsBnejYa8pNsGEKSDHPT28XCXaN8dbSpFK1hLUgy1xM/s4BfdJ62JOYuQLbmqiGR9F bJEspwhS2CmTAAg3XLbSqM2/bN/DNEhAHQNjQ+KyyCLHj1kA6xrrMsRVbnULDCgWMWK9 QoHi+vdTdok2gR5XCpFVlKMUQRsRxcKEn4t24wTJDhmvwmGShxBqlTXzDTekITD14T9t MjrgZWpYdFowMfSTmITNfEK+ttvd8VgPLYsX+MCAxDDYRnHPSCYw/qO/IPboQNLk/Ki1 M3RA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :arc-authentication-results; bh=3lILEdOyDcuwCjUj5fnmv0VUfx2dmdIeRRww4t05//8=; b=WIBYoVN5HL6hok+N43O3jF65DwnGCSCFjlXsoUqNzbadgA/LQmtP4fvueS8Q4qM6Ml kT2YqLJ8xBDF9ABwzsPtKSgDuijpAhXWvb0Vet6GPYU8e7GlGUVLF4XiwRcB4gH3RME7 KqhNmJAbEAuTb+Gwv32o3f38sJ7QpulX91QmvgIiH1Q5BjDosZIcHaCAiTH58Bl+dMPO FQtP+goY1xTrJolYukprQFsvHXtLZsD5faP0UMH6mF13/qhkOsYSufn2H9cQDwZ4LXvR 8UKJrz48TPfUMTsqdKSAaTif15e8wEJ+yki5o4eoNScQlo6BmwbTUlqiZ75n9vqIM6mY O+8g== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of vadimp@mellanox.com designates 193.47.165.129 as permitted sender) smtp.mailfrom=vadimp@mellanox.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=mellanox.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of vadimp@mellanox.com designates 193.47.165.129 as permitted sender) smtp.mailfrom=vadimp@mellanox.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=mellanox.com From: Vadim Pasternak To: dvhart@infradead.org, andy.shevchenko@gmail.com, gregkh@linuxfoundation.org Cc: platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, jiri@resnulli.us, michaelsh@mellanox.com, Vadim Pasternak Subject: [PATCH v1 2/4] platform/x86: mlx-platform: Add differed bus functionality Date: Tue, 13 Feb 2018 22:09:34 +0000 Message-Id: <1518559776-188942-3-git-send-email-vadimp@mellanox.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1518559776-188942-1-git-send-email-vadimp@mellanox.com> References: <1518559776-188942-1-git-send-email-vadimp@mellanox.com> X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1592318017732489878?= X-GMAIL-MSGID: =?utf-8?q?1592318017732489878?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Add deferred bus functionality in order to enforce probing flow execution order. Driver mlx-platform activates platform driver i2c-mux-reg, which creates busses infrastructure, after that it activates mlxreg-hotplug driver, which uses these busses, for connecting devices. The possible miss-ordering can happened, for example in case the probing routine of mlxreg-hotplug is already started execution, while i2c-mux-reg probing routine is not completed yet. In such situation the first one could attempt to connect device to adapter number, which is not created yet. And as a result this connection will fail. In order to ensure the order of probing execution on mlxreg-hotplug probe routine will be deferred until all the busses is not created by probe routine of i2c-mux-reg. In order to ensure the flow order, mlx-platform driver passes the highest bus number to the mlxreg-hotplug platform data, which in their turn could wait in the deferred state, until all the necessary buses topology is not exist. Signed-off-by: Vadim Pasternak --- drivers/platform/mellanox/mlxreg-hotplug.c | 7 +++++++ drivers/platform/x86/mlx-platform.c | 10 ++++++++++ include/linux/platform_data/mlxreg.h | 2 ++ 3 files changed, 19 insertions(+) diff --git a/drivers/platform/mellanox/mlxreg-hotplug.c b/drivers/platform/mellanox/mlxreg-hotplug.c index 313cf8a..fe4910b 100644 --- a/drivers/platform/mellanox/mlxreg-hotplug.c +++ b/drivers/platform/mellanox/mlxreg-hotplug.c @@ -550,6 +550,7 @@ static int mlxreg_hotplug_probe(struct platform_device *pdev) { struct mlxreg_core_hotplug_platform_data *pdata; struct mlxreg_hotplug_priv_data *priv; + struct i2c_adapter *deferred_adap; int err; pdata = dev_get_platdata(&pdev->dev); @@ -558,6 +559,12 @@ static int mlxreg_hotplug_probe(struct platform_device *pdev) return -EINVAL; } + /* Defer probing if the necessary adapter is not configured yet. */ + deferred_adap = i2c_get_adapter(pdata->deferred_nr); + if (!deferred_adap) + return -EPROBE_DEFER; + i2c_put_adapter(deferred_adap); + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; diff --git a/drivers/platform/x86/mlx-platform.c b/drivers/platform/x86/mlx-platform.c index 71b452a..67f3c6d 100644 --- a/drivers/platform/x86/mlx-platform.c +++ b/drivers/platform/x86/mlx-platform.c @@ -697,6 +697,8 @@ static int __init mlxplat_dmi_default_matched(const struct dmi_system_id *dmi) ARRAY_SIZE(mlxplat_default_channels[i]); } mlxplat_hotplug = &mlxplat_mlxcpld_default_data; + mlxplat_hotplug->deferred_nr = + mlxplat_default_channels[i - 1][MLXPLAT_CPLD_GRP_CHNL_NUM - 1]; return 1; }; @@ -711,6 +713,8 @@ static int __init mlxplat_dmi_msn21xx_matched(const struct dmi_system_id *dmi) ARRAY_SIZE(mlxplat_msn21xx_channels); } mlxplat_hotplug = &mlxplat_mlxcpld_msn21xx_data; + mlxplat_hotplug->deferred_nr = + mlxplat_msn21xx_channels[MLXPLAT_CPLD_GRP_CHNL_NUM - 1]; return 1; }; @@ -725,6 +729,8 @@ static int __init mlxplat_dmi_msn274x_matched(const struct dmi_system_id *dmi) ARRAY_SIZE(mlxplat_msn21xx_channels); } mlxplat_hotplug = &mlxplat_mlxcpld_msn274x_data; + mlxplat_hotplug->deferred_nr = + mlxplat_msn21xx_channels[MLXPLAT_CPLD_GRP_CHNL_NUM - 1]; return 1; }; @@ -739,6 +745,8 @@ static int __init mlxplat_dmi_msn201x_matched(const struct dmi_system_id *dmi) ARRAY_SIZE(mlxplat_msn21xx_channels); } mlxplat_hotplug = &mlxplat_mlxcpld_msn201x_data; + mlxplat_hotplug->deferred_nr = + mlxplat_default_channels[i - 1][MLXPLAT_CPLD_GRP_CHNL_NUM - 1]; return 1; }; @@ -753,6 +761,8 @@ static int __init mlxplat_dmi_qmb7xx_matched(const struct dmi_system_id *dmi) ARRAY_SIZE(mlxplat_msn21xx_channels); } mlxplat_hotplug = &mlxplat_mlxcpld_default_ng_data; + mlxplat_hotplug->deferred_nr = + mlxplat_msn21xx_channels[MLXPLAT_CPLD_GRP_CHNL_NUM - 1]; return 1; }; diff --git a/include/linux/platform_data/mlxreg.h b/include/linux/platform_data/mlxreg.h index fcdc707..2629109 100644 --- a/include/linux/platform_data/mlxreg.h +++ b/include/linux/platform_data/mlxreg.h @@ -129,6 +129,7 @@ struct mlxreg_core_platform_data { * @mask: top aggregation interrupt common mask; * @cell_low: location of low aggregation interrupt register; * @mask_low: low aggregation interrupt common mask; + * @deferred_nr: I2C adapter number must be exist prior probing execution; */ struct mlxreg_core_hotplug_platform_data { struct mlxreg_core_item *items; @@ -139,6 +140,7 @@ struct mlxreg_core_hotplug_platform_data { u32 mask; u32 cell_low; u32 mask_low; + int deferred_nr; }; #endif /* __LINUX_PLATFORM_DATA_MLXREG_H */ -- 2.1.4