Re: [PATCH V3 1/2] mtd: allow getting MTD device associated with a specific DT node
Hello Rafał,
On 11.06.22 22:46, Rafał Miłecki wrote:
> From: Rafał Miłecki
>
> MTD subsystem API allows interacting with MTD devices (e.g. reading,
> writing, handling bad blocks). So far a random driver could get MTD
> device only by its name (get_mtd_device_nm()). This change allows
> getting them also by a DT node.
>
> This API is required for drivers handling DT defined MTD partitions in a
> specific way (e.g. U-Boot (sub)partition with environment variables).
>
> Signed-off-by: Rafał Miłecki
> ---
> V3: First introduction of of_get_mtd_device_by_node()
>
> mtd maintainers: please let know how would you like this patch
> processed. Would that be OK for you to Review/Ack it and let it go
> through NVMEM tree?
> ---
> drivers/mtd/mtdcore.c | 28
> include/linux/mtd/mtd.h | 1 +
> 2 files changed, 29 insertions(+)
>
> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> index 9eb0680db312..7dc214271c85 100644
> --- a/drivers/mtd/mtdcore.c
> +++ b/drivers/mtd/mtdcore.c
> @@ -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)
> +{
> + struct mtd_info *mtd = NULL;
> + struct mtd_info *tmp;
> + int err;
> +
> + mutex_lock(_table_mutex);
> +
> + err = -ENODEV;
Shouldn't this be -EPROBE_DEFER? That way drivers making
use of this function can defer probe until the device
is probed.
> + mtd_for_each_device(tmp) {
> + if (mtd_get_of_node(tmp) == np) {
> + mtd = tmp;
> + err = __get_mtd_device(mtd);
> + break;
> + }
> + }
> +
> + mutex_unlock(_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
> diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
> index 955aee14b0f7..6fc841ceef31 100644
> --- a/include/linux/mtd/mtd.h
> +++ b/include/linux/mtd/mtd.h
> @@ -677,6 +677,7 @@ extern int mtd_device_unregister(struct mtd_info *master);
> extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
> extern int __get_mtd_device(struct mtd_info *mtd);
> extern void __put_mtd_device(struct mtd_info *mtd);
> +extern struct mtd_info *of_get_mtd_device_by_node(struct device_node *np);
> extern struct mtd_info *get_mtd_device_nm(const char *name);
> extern void put_mtd_device(struct mtd_info *mtd);
>
--
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Re: [PATCH V3 1/2] mtd: allow getting MTD device associated with a specific DT node
Hi Rafał,
zaj...@gmail.com wrote on Mon, 13 Jun 2022 16:15:34 +0200:
> 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:
I know most implementation today use of_ functions directly but it
seems like there is a global move towards fwnodes now, and I was
wondering if using those instead (which might also apply to other types
of "nodes" than DT ones) could be possible.
But looking into existing implementations, I came across the pwm implem
which features:
- of_pwm_get()
- acpi_pwm_get()
And finally a fwnode_pwm_get() which does:
if (is_of_node())
of_pwm_get():
else if (is_acpi_node())
acpi_pwm_get();
So actually my suggestion is meaningless. I'm fine with the current
approach.
Acked-by: Miquel Raynal
>
> $ 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(_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(_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
>
Thanks,
Miquèl
Re: [PATCH V3 1/2] mtd: allow getting MTD device associated with a specific DT node
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(_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(_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
Re: [PATCH V3 1/2] mtd: allow getting MTD device associated with a specific DT node
Hi Rafał,
zaj...@gmail.com wrote on Sat, 11 Jun 2022 22:46:50 +0200:
> From: Rafał Miłecki
>
> MTD subsystem API allows interacting with MTD devices (e.g. reading,
> writing, handling bad blocks). So far a random driver could get MTD
> device only by its name (get_mtd_device_nm()). This change allows
> getting them also by a DT node.
>
> This API is required for drivers handling DT defined MTD partitions in a
> specific way (e.g. U-Boot (sub)partition with environment variables).
>
> Signed-off-by: Rafał Miłecki
> ---
> V3: First introduction of of_get_mtd_device_by_node()
>
> mtd maintainers: please let know how would you like this patch
> processed. Would that be OK for you to Review/Ack it and let it go
> through NVMEM tree?
Yes
> ---
> drivers/mtd/mtdcore.c | 28
> include/linux/mtd/mtd.h | 1 +
> 2 files changed, 29 insertions(+)
>
> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> index 9eb0680db312..7dc214271c85 100644
> --- a/drivers/mtd/mtdcore.c
> +++ b/drivers/mtd/mtdcore.c
> @@ -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?
> +{
> + struct mtd_info *mtd = NULL;
> + struct mtd_info *tmp;
> + int err;
> +
> + mutex_lock(_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(_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
> diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
> index 955aee14b0f7..6fc841ceef31 100644
> --- a/include/linux/mtd/mtd.h
> +++ b/include/linux/mtd/mtd.h
> @@ -677,6 +677,7 @@ extern int mtd_device_unregister(struct mtd_info *master);
> extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
> extern int __get_mtd_device(struct mtd_info *mtd);
> extern void __put_mtd_device(struct mtd_info *mtd);
> +extern struct mtd_info *of_get_mtd_device_by_node(struct device_node *np);
> extern struct mtd_info *get_mtd_device_nm(const char *name);
> extern void put_mtd_device(struct mtd_info *mtd);
>
Thanks,
Miquèl
[PATCH V3 1/2] mtd: allow getting MTD device associated with a specific DT node
From: Rafał Miłecki
MTD subsystem API allows interacting with MTD devices (e.g. reading,
writing, handling bad blocks). So far a random driver could get MTD
device only by its name (get_mtd_device_nm()). This change allows
getting them also by a DT node.
This API is required for drivers handling DT defined MTD partitions in a
specific way (e.g. U-Boot (sub)partition with environment variables).
Signed-off-by: Rafał Miłecki
---
V3: First introduction of of_get_mtd_device_by_node()
mtd maintainers: please let know how would you like this patch
processed. Would that be OK for you to Review/Ack it and let it go
through NVMEM tree?
---
drivers/mtd/mtdcore.c | 28
include/linux/mtd/mtd.h | 1 +
2 files changed, 29 insertions(+)
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 9eb0680db312..7dc214271c85 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -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)
+{
+ struct mtd_info *mtd = NULL;
+ struct mtd_info *tmp;
+ int err;
+
+ mutex_lock(_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(_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
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 955aee14b0f7..6fc841ceef31 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -677,6 +677,7 @@ extern int mtd_device_unregister(struct mtd_info *master);
extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
extern int __get_mtd_device(struct mtd_info *mtd);
extern void __put_mtd_device(struct mtd_info *mtd);
+extern struct mtd_info *of_get_mtd_device_by_node(struct device_node *np);
extern struct mtd_info *get_mtd_device_nm(const char *name);
extern void put_mtd_device(struct mtd_info *mtd);
--
2.34.1
