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charset="utf-8" X-Sendblock-Type: SVC_REQ_APPROVE CMS-TYPE: 101P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20211217062932epcas1p1b262f3dd17607f5e42b85c169729ce63 References: <20211217062846.GA26548@kili> <978e3529-512a-3fc6-3a9f-5f34d5fd6ce7@samsung.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dear all, Applied it. Thanks. Best Regards, Chanwoo Choi On 2/3/22 2:24 PM, Chanwoo Choi wrote: > Hi Felipe, > > Gently Ping. > > Best Regards, > Chanwoo Choi > > On 12/20/21 10:20 AM, Chanwoo Choi wrote: >> Hi Sebastian and Felipe, >> >> If Sebastian and Felipe don't have any additional opinion, >> could you please reply the review for this patch? >> >> And if Sebastian and Felipe agree, I'll merge it to extcon tree. >> >> >> Best Regards, >> Chanwoo Choi >> >> >> On 12/17/21 3:28 PM, Dan Carpenter wrote: >>> The extcon_get_extcon_dev() function returns error pointers on error, >>> NULL when it's a -EPROBE_DEFER defer situation, and ERR_PTR(-ENODEV) >>> when the CONFIG_EXTCON option is disabled. This is very complicated for >>> the callers to handle and a number of them had bugs that would lead to >>> an Oops. >>> >>> In real life, there are two things which prevented crashes. First, >>> error pointers would only be returned if there was bug in the caller >>> where they passed a NULL "extcon_name" and none of them do that. >>> Second, only two out of the eight drivers will build when CONFIG_EXTCON >>> is disabled. >>> >>> The normal way to write this would be to return -EPROBE_DEFER directly >>> when appropriate and return NULL when CONFIG_EXTCON is disabled. Then >>> the error handling is simple and just looks like: >>> >>> dev->edev = extcon_get_extcon_dev(acpi_dev_name(adev)); >>> if (IS_ERR(dev->edev)) >>> return PTR_ERR(dev->edev); >>> >>> For the two drivers which can build with CONFIG_EXTCON disabled, then >>> extcon_get_extcon_dev() will now return NULL which is not treated as an >>> error and the probe will continue successfully. Those two drivers are >>> "typec_fusb302" and "max8997-battery". In the original code, the >>> typec_fusb302 driver had an 800ms hang in tcpm_get_current_limit() but >>> now that function is a no-op. For the max8997-battery driver everything >>> should continue working as is. >>> >>> Signed-off-by: Dan Carpenter >>> --- >>> v2: return NULL when CONFIG_EXTCON is disabled >>> v3: Add a note to extcon_get_extcon_dev() to say that it may only be >>> called from probe(). >>> >>> drivers/extcon/extcon.c | 4 +++- >>> include/linux/extcon.h | 2 +- >>> drivers/extcon/extcon-axp288.c | 4 ++-- >>> drivers/power/supply/axp288_charger.c | 17 ++++++++++------- >>> drivers/power/supply/charger-manager.c | 7 ++----- >>> drivers/power/supply/max8997_charger.c | 10 +++++----- >>> drivers/usb/dwc3/drd.c | 9 ++------- >>> drivers/usb/phy/phy-omap-otg.c | 4 ++-- >>> drivers/usb/typec/tcpm/fusb302.c | 4 ++-- >>> 9 files changed, 29 insertions(+), 32 deletions(-) >>> >>> diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c >>> index e7a9561a826d..9eb92997f3ae 100644 >>> --- a/drivers/extcon/extcon.c >>> +++ b/drivers/extcon/extcon.c >>> @@ -863,6 +863,8 @@ EXPORT_SYMBOL_GPL(extcon_set_property_capability); >>> * @extcon_name: the extcon name provided with extcon_dev_register() >>> * >>> * Return the pointer of extcon device if success or ERR_PTR(err) if fail. >>> + * NOTE: This function returns -EPROBE_DEFER so it may only be called from >>> + * probe() functions. >>> */ >>> struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name) >>> { >>> @@ -876,7 +878,7 @@ struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name) >>> if (!strcmp(sd->name, extcon_name)) >>> goto out; >>> } >>> - sd = NULL; >>> + sd = ERR_PTR(-EPROBE_DEFER); >>> out: >>> mutex_unlock(&extcon_dev_list_lock); >>> return sd; >>> diff --git a/include/linux/extcon.h b/include/linux/extcon.h >>> index 0c19010da77f..685401d94d39 100644 >>> --- a/include/linux/extcon.h >>> +++ b/include/linux/extcon.h >>> @@ -296,7 +296,7 @@ static inline void devm_extcon_unregister_notifier_all(struct device *dev, >>> >>> static inline struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name) >>> { >>> - return ERR_PTR(-ENODEV); >>> + return NULL; >>> } >>> >>> static inline struct extcon_dev *extcon_find_edev_by_node(struct device_node *node) >>> diff --git a/drivers/extcon/extcon-axp288.c b/drivers/extcon/extcon-axp288.c >>> index 7c6d5857ff25..180be768c215 100644 >>> --- a/drivers/extcon/extcon-axp288.c >>> +++ b/drivers/extcon/extcon-axp288.c >>> @@ -394,8 +394,8 @@ static int axp288_extcon_probe(struct platform_device *pdev) >>> if (adev) { >>> info->id_extcon = extcon_get_extcon_dev(acpi_dev_name(adev)); >>> put_device(&adev->dev); >>> - if (!info->id_extcon) >>> - return -EPROBE_DEFER; >>> + if (IS_ERR(info->id_extcon)) >>> + return PTR_ERR(info->id_extcon); >>> >>> dev_info(dev, "controlling USB role\n"); >>> } else { >>> diff --git a/drivers/power/supply/axp288_charger.c b/drivers/power/supply/axp288_charger.c >>> index ec41f6cd3f93..4acfeb52a44e 100644 >>> --- a/drivers/power/supply/axp288_charger.c >>> +++ b/drivers/power/supply/axp288_charger.c >>> @@ -848,17 +848,20 @@ static int axp288_charger_probe(struct platform_device *pdev) >>> info->regmap_irqc = axp20x->regmap_irqc; >>> >>> info->cable.edev = extcon_get_extcon_dev(AXP288_EXTCON_DEV_NAME); >>> - if (info->cable.edev == NULL) { >>> - dev_dbg(dev, "%s is not ready, probe deferred\n", >>> - AXP288_EXTCON_DEV_NAME); >>> - return -EPROBE_DEFER; >>> + if (IS_ERR(info->cable.edev)) { >>> + dev_err_probe(dev, PTR_ERR(info->cable.edev), >>> + "extcon_get_extcon_dev(%s) failed\n", >>> + AXP288_EXTCON_DEV_NAME); >>> + return PTR_ERR(info->cable.edev); >>> } >>> >>> if (acpi_dev_present(USB_HOST_EXTCON_HID, NULL, -1)) { >>> info->otg.cable = extcon_get_extcon_dev(USB_HOST_EXTCON_NAME); >>> - if (info->otg.cable == NULL) { >>> - dev_dbg(dev, "EXTCON_USB_HOST is not ready, probe deferred\n"); >>> - return -EPROBE_DEFER; >>> + if (IS_ERR(info->otg.cable)) { >>> + dev_err_probe(dev, PTR_ERR(info->otg.cable), >>> + "extcon_get_extcon_dev(%s) failed\n", >>> + USB_HOST_EXTCON_NAME); >>> + return PTR_ERR(info->otg.cable); >>> } >>> dev_info(dev, "Using " USB_HOST_EXTCON_HID " extcon for usb-id\n"); >>> } >>> diff --git a/drivers/power/supply/charger-manager.c b/drivers/power/supply/charger-manager.c >>> index d67edb760c94..92db79400a6a 100644 >>> --- a/drivers/power/supply/charger-manager.c >>> +++ b/drivers/power/supply/charger-manager.c >>> @@ -985,13 +985,10 @@ static int charger_extcon_init(struct charger_manager *cm, >>> cable->nb.notifier_call = charger_extcon_notifier; >>> >>> cable->extcon_dev = extcon_get_extcon_dev(cable->extcon_name); >>> - if (IS_ERR_OR_NULL(cable->extcon_dev)) { >>> + if (IS_ERR(cable->extcon_dev)) { >>> pr_err("Cannot find extcon_dev for %s (cable: %s)\n", >>> cable->extcon_name, cable->name); >>> - if (cable->extcon_dev == NULL) >>> - return -EPROBE_DEFER; >>> - else >>> - return PTR_ERR(cable->extcon_dev); >>> + return PTR_ERR(cable->extcon_dev); >>> } >>> >>> for (i = 0; i < ARRAY_SIZE(extcon_mapping); i++) { >>> diff --git a/drivers/power/supply/max8997_charger.c b/drivers/power/supply/max8997_charger.c >>> index 25207fe2aa68..634658adf313 100644 >>> --- a/drivers/power/supply/max8997_charger.c >>> +++ b/drivers/power/supply/max8997_charger.c >>> @@ -248,13 +248,13 @@ static int max8997_battery_probe(struct platform_device *pdev) >>> dev_info(&pdev->dev, "couldn't get charger regulator\n"); >>> } >>> charger->edev = extcon_get_extcon_dev("max8997-muic"); >>> - if (IS_ERR_OR_NULL(charger->edev)) { >>> - if (!charger->edev) >>> - return -EPROBE_DEFER; >>> - dev_info(charger->dev, "couldn't get extcon device\n"); >>> + if (IS_ERR(charger->edev)) { >>> + dev_err_probe(charger->dev, PTR_ERR(charger->edev), >>> + "couldn't get extcon device: max8997-muic\n"); >>> + return PTR_ERR(charger->edev); >>> } >>> >>> - if (!IS_ERR(charger->reg) && !IS_ERR_OR_NULL(charger->edev)) { >>> + if (!IS_ERR(charger->reg)) { >>> INIT_WORK(&charger->extcon_work, max8997_battery_extcon_evt_worker); >>> ret = devm_add_action(&pdev->dev, max8997_battery_extcon_evt_stop_work, charger); >>> if (ret) { >>> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c >>> index d7f76835137f..a490f79131c1 100644 >>> --- a/drivers/usb/dwc3/drd.c >>> +++ b/drivers/usb/dwc3/drd.c >>> @@ -454,13 +454,8 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc) >>> * This device property is for kernel internal use only and >>> * is expected to be set by the glue code. >>> */ >>> - if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) { >>> - edev = extcon_get_extcon_dev(name); >>> - if (!edev) >>> - return ERR_PTR(-EPROBE_DEFER); >>> - >>> - return edev; >>> - } >>> + if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) >>> + return extcon_get_extcon_dev(name); >>> >>> /* >>> * Try to get an extcon device from the USB PHY controller's "port" >>> diff --git a/drivers/usb/phy/phy-omap-otg.c b/drivers/usb/phy/phy-omap-otg.c >>> index ee0863c6553e..6e6ef8c0bc7e 100644 >>> --- a/drivers/usb/phy/phy-omap-otg.c >>> +++ b/drivers/usb/phy/phy-omap-otg.c >>> @@ -95,8 +95,8 @@ static int omap_otg_probe(struct platform_device *pdev) >>> return -ENODEV; >>> >>> extcon = extcon_get_extcon_dev(config->extcon); >>> - if (!extcon) >>> - return -EPROBE_DEFER; >>> + if (IS_ERR(extcon)) >>> + return PTR_ERR(extcon); >>> >>> otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL); >>> if (!otg_dev) >>> diff --git a/drivers/usb/typec/tcpm/fusb302.c b/drivers/usb/typec/tcpm/fusb302.c >>> index 72f9001b0792..96c55eaf3f80 100644 >>> --- a/drivers/usb/typec/tcpm/fusb302.c >>> +++ b/drivers/usb/typec/tcpm/fusb302.c >>> @@ -1708,8 +1708,8 @@ static int fusb302_probe(struct i2c_client *client, >>> */ >>> if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) { >>> chip->extcon = extcon_get_extcon_dev(name); >>> - if (!chip->extcon) >>> - return -EPROBE_DEFER; >>> + if (IS_ERR(chip->extcon)) >>> + return PTR_ERR(chip->extcon); >>> } >>> >>> chip->vbus = devm_regulator_get(chip->dev, "vbus"); >>> >> >> >> >> > >