[PATCH V3 1/2] mtd: allow getting MTD device associated with a specific DT node

[Rafał Miłecki]

On 13.06.2022 16:04, Miquel Raynal wrote:
>> @@ -1154,6 +1154,34 @@ int __get_mtd_device(struct mtd_info *mtd)
>>   }
>>   EXPORT_SYMBOL_GPL(__get_mtd_device);
>>   
>> +/**
>> + * of_get_mtd_device_by_node - obtain an MTD device associated with a given node
>> + *
>> + * @np: device tree node
>> + */
>> +struct mtd_info *of_get_mtd_device_by_node(struct device_node *np)
> 
> Shall we try to use a more of-agnostic syntax or is it too complex here?

I need some extra hint, please. This is how many similar functions look
like:

$ grep -E -r "(get|find).*_by_node" ./include/*
./include/drm/drm_mipi_dsi.h:struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node);
./include/drm/drm_mipi_dsi.h:struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node *np);
./include/linux/usb/phy.h:extern struct usb_phy *devm_usb_get_phy_by_node(struct device *dev,
./include/linux/usb/phy.h:static inline struct usb_phy *devm_usb_get_phy_by_node(struct device *dev,
./include/linux/extcon.h:struct extcon_dev *extcon_find_edev_by_node(struct device_node *node);
./include/linux/extcon.h:static inline struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
./include/linux/of_net.h:extern struct net_device *of_find_net_device_by_node(struct device_node *np);
./include/linux/of_net.h:static inline struct net_device *of_find_net_device_by_node(struct device_node *np)
./include/linux/devfreq.h:struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node);
./include/linux/devfreq.h:static inline struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node)
./include/linux/of_platform.h:extern struct platform_device *of_find_device_by_node(struct device_node *np);
./include/linux/of_platform.h:static inline struct platform_device *of_find_device_by_node(struct device_node *np)
./include/linux/backlight.h:struct backlight_device *of_find_backlight_by_node(struct device_node *node);
./include/linux/backlight.h:of_find_backlight_by_node(struct device_node *node)
./include/linux/i2c.h:struct i2c_client *of_find_i2c_device_by_node(struct device_node *node);
./include/linux/i2c.h:struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node);
./include/linux/i2c.h:struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node);
./include/linux/i2c.h:static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
./include/linux/i2c.h:static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
./include/linux/i2c.h:static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)


>> +{
>> +	struct mtd_info *mtd = NULL;
>> +	struct mtd_info *tmp;
>> +	int err;
>> +
>> +	mutex_lock(&mtd_table_mutex);
>> +
>> +	err = -ENODEV;
>> +	mtd_for_each_device(tmp) {
>> +		if (mtd_get_of_node(tmp) == np) {
>> +			mtd = tmp;
>> +			err = __get_mtd_device(mtd);
>> +			break;
>> +		}
>> +	}
>> +
>> +	mutex_unlock(&mtd_table_mutex);
>> +
>> +	return err ? ERR_PTR(err) : mtd;
>> +}
>> +EXPORT_SYMBOL_GPL(of_get_mtd_device_by_node);
>> +
>>   /**
>>    *	get_mtd_device_nm - obtain a validated handle for an MTD device by
>>    *	device name