diff mbox series

[RESEND,v3,1/2] of: base: Introduce of_alias_get_alias_list() to check alias IDs

Message ID b1772d99d4e8b788448cde0fc5c7dccb1f63b507.1537443710.git.michal.simek@xilinx.com
State Not Applicable, archived
Headers show
Series [RESEND,v3,1/2] of: base: Introduce of_alias_get_alias_list() to check alias IDs | expand

Commit Message

Michal Simek Sept. 20, 2018, 11:41 a.m. UTC 
The function travels the lookup table to record alias ids for the given
device match structures and alias stem.
This function will be used by serial drivers to check if requested alias
is allocated or free to use.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---

Changes in v3:
- Fix subject s/of_alias_check_id/of_alias_get_alias_list/
- And also fix commit message description to match
  of_alias_get_alias_list()
- mark empty function with inline

Changes in v2:
- Add empty function for !CONFIG_OF case
- Add return to that function
- Add Rob's Reviewed-by tag

Based on discussion with Rob
https://lkml.org/lkml/2018/4/27/397
nbits is passed to the function not to limit only to 32/64bit fields.

Greg: Please apply this together with serial: uartps: Change uart ID
port allocation. Rob is fine with that (link above)

---
 drivers/of/base.c  | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/of.h | 10 ++++++++++
 2 files changed, 62 insertions(+)

Comments

Geert Uytterhoeven Sept. 24, 2018, 7:41 a.m. UTC | #1 
Hi Michal,

On Thu, Sep 20, 2018 at 1:42 PM Michal Simek <michal.simek@xilinx.com> wrote:
> The function travels the lookup table to record alias ids for the given
> device match structures and alias stem.
> This function will be used by serial drivers to check if requested alias
> is allocated or free to use.
>
> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
> Reviewed-by: Rob Herring <robh@kernel.org>

I know this has already been applied, it just drew my attention.

> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -16,6 +16,7 @@
>
>  #define pr_fmt(fmt)    "OF: " fmt
>
> +#include <linux/bitmap.h>
>  #include <linux/console.h>
>  #include <linux/ctype.h>
>  #include <linux/cpu.h>
> @@ -1943,6 +1944,57 @@ int of_alias_get_id(struct device_node *np, const char *stem)
>  EXPORT_SYMBOL_GPL(of_alias_get_id);
>
>  /**
> + * of_alias_get_alias_list - Get alias list for the given device driver
> + * @matches:   Array of OF device match structures to search in
> + * @stem:      Alias stem of the given device_node
> + * @bitmap:    Bitmap field pointer
> + * @nbits:     Maximum number of alias ID which can be recorded it bitmap

IDs

> + *
> + * The function travels the lookup table to record alias ids for the given
> + * device match structures and alias stem.
> + *
> + * Return:     0 or -ENOSYS when !CONFIG_OF
> + */
> +int of_alias_get_alias_list(const struct of_device_id *matches,
> +                            const char *stem, unsigned long *bitmap,
> +                            unsigned int nbits)
> +{
> +       struct alias_prop *app;
> +
> +       /* Zero bitmap field to make sure that all the time it is clean */
> +       bitmap_zero(bitmap, nbits);
> +
> +       mutex_lock(&of_mutex);
> +       pr_debug("%s: Looking for stem: %s\n", __func__, stem);
> +       list_for_each_entry(app, &aliases_lookup, link) {
> +               pr_debug("%s: stem: %s, id: %d\n",
> +                        __func__, app->stem, app->id);
> +
> +               if (strcmp(app->stem, stem) != 0) {
> +                       pr_debug("%s: stem comparison doesn't passed %s\n",

didn't pass?

> +                                __func__, app->stem);
> +                       continue;
> +               }
> +
> +               if (app->id >= nbits) {
> +                       pr_debug("%s: ID %d greater then bitmap field %d\n",

than
%u for unsigned int

> +                               __func__, app->id, nbits);
> +                       continue;

Shouldn't this return an error, if of_match_node() below would have matched?

> +               }
> +
> +               if (of_match_node(matches, app->np)) {
> +                       pr_debug("%s: Allocated ID %d\n", __func__, app->id);
> +                       set_bit(app->id, bitmap);
> +               }
> +               /* Alias exist but it not compatible with matches */

exists but is npt

> +       }
> +       mutex_unlock(&of_mutex);
> +
> +       return 0;
> +}
> +EXPORT_SYMBOL_GPL(of_alias_get_alias_list);
> +
> +/**
>   * of_alias_get_highest_id - Get highest alias id for the given stem
>   * @stem:      Alias stem to be examined
>   *

Gr{oetje,eeting}s,

                        Geert
Michal Simek Sept. 26, 2018, 11:01 a.m. UTC | #2 
On 24.9.2018 09:41, Geert Uytterhoeven wrote:
> Hi Michal,
> 
> On Thu, Sep 20, 2018 at 1:42 PM Michal Simek <michal.simek@xilinx.com> wrote:
>> The function travels the lookup table to record alias ids for the given
>> device match structures and alias stem.
>> This function will be used by serial drivers to check if requested alias
>> is allocated or free to use.
>>
>> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
>> Reviewed-by: Rob Herring <robh@kernel.org>
> 
> I know this has already been applied, it just drew my attention.
> 
>> --- a/drivers/of/base.c
>> +++ b/drivers/of/base.c
>> @@ -16,6 +16,7 @@
>>
>>  #define pr_fmt(fmt)    "OF: " fmt
>>
>> +#include <linux/bitmap.h>
>>  #include <linux/console.h>
>>  #include <linux/ctype.h>
>>  #include <linux/cpu.h>
>> @@ -1943,6 +1944,57 @@ int of_alias_get_id(struct device_node *np, const char *stem)
>>  EXPORT_SYMBOL_GPL(of_alias_get_id);
>>
>>  /**
>> + * of_alias_get_alias_list - Get alias list for the given device driver
>> + * @matches:   Array of OF device match structures to search in
>> + * @stem:      Alias stem of the given device_node
>> + * @bitmap:    Bitmap field pointer
>> + * @nbits:     Maximum number of alias ID which can be recorded it bitmap
> 
> IDs
> 
>> + *
>> + * The function travels the lookup table to record alias ids for the given
>> + * device match structures and alias stem.
>> + *
>> + * Return:     0 or -ENOSYS when !CONFIG_OF
>> + */
>> +int of_alias_get_alias_list(const struct of_device_id *matches,
>> +                            const char *stem, unsigned long *bitmap,
>> +                            unsigned int nbits)
>> +{
>> +       struct alias_prop *app;
>> +
>> +       /* Zero bitmap field to make sure that all the time it is clean */
>> +       bitmap_zero(bitmap, nbits);
>> +
>> +       mutex_lock(&of_mutex);
>> +       pr_debug("%s: Looking for stem: %s\n", __func__, stem);
>> +       list_for_each_entry(app, &aliases_lookup, link) {
>> +               pr_debug("%s: stem: %s, id: %d\n",
>> +                        __func__, app->stem, app->id);
>> +
>> +               if (strcmp(app->stem, stem) != 0) {
>> +                       pr_debug("%s: stem comparison doesn't passed %s\n",
> 
> didn't pass?
> 
>> +                                __func__, app->stem);
>> +                       continue;
>> +               }
>> +
>> +               if (app->id >= nbits) {
>> +                       pr_debug("%s: ID %d greater then bitmap field %d\n",
> 
> than
> %u for unsigned int

I won't fix this now because this can be done together with one change
described below.

> 
>> +                               __func__, app->id, nbits);
>> +                       continue;
> 
> Shouldn't this return an error, if of_match_node() below would have matched?

IIRC Above check is for "serial" name.
This one is for getting XX number from alias "serialXX".
And below is checking compatible string.

You are calling this function from uartps with 32 lines limit and there
is serial33 alias poiting to uartlite (for example) then you don't want
to break this call for that.

What can be done is that compatible string is checked first and if this
passed then ids are check and error can be returned or bit sets.

Thanks,
Michal
Geert Uytterhoeven Sept. 27, 2018, 7:19 a.m. UTC | #3 
Hi Michal,

On Wed, Sep 26, 2018 at 1:01 PM Michal Simek <michal.simek@xilinx.com> wrote:
> On 24.9.2018 09:41, Geert Uytterhoeven wrote:
> > On Thu, Sep 20, 2018 at 1:42 PM Michal Simek <michal.simek@xilinx.com> wrote:
> >> The function travels the lookup table to record alias ids for the given
> >> device match structures and alias stem.
> >> This function will be used by serial drivers to check if requested alias
> >> is allocated or free to use.
> >>
> >> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
> >> Reviewed-by: Rob Herring <robh@kernel.org>
> >
> > I know this has already been applied, it just drew my attention.
> >
> >> --- a/drivers/of/base.c
> >> +++ b/drivers/of/base.c
> >> @@ -16,6 +16,7 @@
> >>
> >>  #define pr_fmt(fmt)    "OF: " fmt
> >>
> >> +#include <linux/bitmap.h>
> >>  #include <linux/console.h>
> >>  #include <linux/ctype.h>
> >>  #include <linux/cpu.h>
> >> @@ -1943,6 +1944,57 @@ int of_alias_get_id(struct device_node *np, const char *stem)
> >>  EXPORT_SYMBOL_GPL(of_alias_get_id);
> >>
> >>  /**
> >> + * of_alias_get_alias_list - Get alias list for the given device driver
> >> + * @matches:   Array of OF device match structures to search in
> >> + * @stem:      Alias stem of the given device_node
> >> + * @bitmap:    Bitmap field pointer
> >> + * @nbits:     Maximum number of alias ID which can be recorded it bitmap
> >
> > IDs
> >
> >> + *
> >> + * The function travels the lookup table to record alias ids for the given
> >> + * device match structures and alias stem.
> >> + *
> >> + * Return:     0 or -ENOSYS when !CONFIG_OF
> >> + */
> >> +int of_alias_get_alias_list(const struct of_device_id *matches,
> >> +                            const char *stem, unsigned long *bitmap,
> >> +                            unsigned int nbits)
> >> +{
> >> +       struct alias_prop *app;
> >> +
> >> +       /* Zero bitmap field to make sure that all the time it is clean */
> >> +       bitmap_zero(bitmap, nbits);
> >> +
> >> +       mutex_lock(&of_mutex);
> >> +       pr_debug("%s: Looking for stem: %s\n", __func__, stem);
> >> +       list_for_each_entry(app, &aliases_lookup, link) {
> >> +               pr_debug("%s: stem: %s, id: %d\n",
> >> +                        __func__, app->stem, app->id);
> >> +
> >> +               if (strcmp(app->stem, stem) != 0) {
> >> +                       pr_debug("%s: stem comparison doesn't passed %s\n",
> >
> > didn't pass?
> >
> >> +                                __func__, app->stem);
> >> +                       continue;
> >> +               }
> >> +
> >> +               if (app->id >= nbits) {
> >> +                       pr_debug("%s: ID %d greater then bitmap field %d\n",
> >
> > than
> > %u for unsigned int
>
> I won't fix this now because this can be done together with one change
> described below.
>
> >
> >> +                               __func__, app->id, nbits);
> >> +                       continue;
> >
> > Shouldn't this return an error, if of_match_node() below would have matched?
>
> IIRC Above check is for "serial" name.
> This one is for getting XX number from alias "serialXX".
> And below is checking compatible string.
>
> You are calling this function from uartps with 32 lines limit and there
> is serial33 alias poiting to uartlite (for example) then you don't want
> to break this call for that.
>
> What can be done is that compatible string is checked first and if this
> passed then ids are check and error can be returned or bit sets.

That's what I meant: currently any serialN with N >= nbits is ignored, even
if the alias applies to the driver that called the function.

Gr{oetje,eeting}s,

                        Geert
Michal Simek Sept. 27, 2018, 7:22 a.m. UTC | #4 
On 27.9.2018 09:19, Geert Uytterhoeven wrote:
> Hi Michal,
> 
> On Wed, Sep 26, 2018 at 1:01 PM Michal Simek <michal.simek@xilinx.com> wrote:
>> On 24.9.2018 09:41, Geert Uytterhoeven wrote:
>>> On Thu, Sep 20, 2018 at 1:42 PM Michal Simek <michal.simek@xilinx.com> wrote:
>>>> The function travels the lookup table to record alias ids for the given
>>>> device match structures and alias stem.
>>>> This function will be used by serial drivers to check if requested alias
>>>> is allocated or free to use.
>>>>
>>>> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
>>>> Reviewed-by: Rob Herring <robh@kernel.org>
>>>
>>> I know this has already been applied, it just drew my attention.
>>>
>>>> --- a/drivers/of/base.c
>>>> +++ b/drivers/of/base.c
>>>> @@ -16,6 +16,7 @@
>>>>
>>>>  #define pr_fmt(fmt)    "OF: " fmt
>>>>
>>>> +#include <linux/bitmap.h>
>>>>  #include <linux/console.h>
>>>>  #include <linux/ctype.h>
>>>>  #include <linux/cpu.h>
>>>> @@ -1943,6 +1944,57 @@ int of_alias_get_id(struct device_node *np, const char *stem)
>>>>  EXPORT_SYMBOL_GPL(of_alias_get_id);
>>>>
>>>>  /**
>>>> + * of_alias_get_alias_list - Get alias list for the given device driver
>>>> + * @matches:   Array of OF device match structures to search in
>>>> + * @stem:      Alias stem of the given device_node
>>>> + * @bitmap:    Bitmap field pointer
>>>> + * @nbits:     Maximum number of alias ID which can be recorded it bitmap
>>>
>>> IDs
>>>
>>>> + *
>>>> + * The function travels the lookup table to record alias ids for the given
>>>> + * device match structures and alias stem.
>>>> + *
>>>> + * Return:     0 or -ENOSYS when !CONFIG_OF
>>>> + */
>>>> +int of_alias_get_alias_list(const struct of_device_id *matches,
>>>> +                            const char *stem, unsigned long *bitmap,
>>>> +                            unsigned int nbits)
>>>> +{
>>>> +       struct alias_prop *app;
>>>> +
>>>> +       /* Zero bitmap field to make sure that all the time it is clean */
>>>> +       bitmap_zero(bitmap, nbits);
>>>> +
>>>> +       mutex_lock(&of_mutex);
>>>> +       pr_debug("%s: Looking for stem: %s\n", __func__, stem);
>>>> +       list_for_each_entry(app, &aliases_lookup, link) {
>>>> +               pr_debug("%s: stem: %s, id: %d\n",
>>>> +                        __func__, app->stem, app->id);
>>>> +
>>>> +               if (strcmp(app->stem, stem) != 0) {
>>>> +                       pr_debug("%s: stem comparison doesn't passed %s\n",
>>>
>>> didn't pass?
>>>
>>>> +                                __func__, app->stem);
>>>> +                       continue;
>>>> +               }
>>>> +
>>>> +               if (app->id >= nbits) {
>>>> +                       pr_debug("%s: ID %d greater then bitmap field %d\n",
>>>
>>> than
>>> %u for unsigned int
>>
>> I won't fix this now because this can be done together with one change
>> described below.
>>
>>>
>>>> +                               __func__, app->id, nbits);
>>>> +                       continue;
>>>
>>> Shouldn't this return an error, if of_match_node() below would have matched?
>>
>> IIRC Above check is for "serial" name.
>> This one is for getting XX number from alias "serialXX".
>> And below is checking compatible string.
>>
>> You are calling this function from uartps with 32 lines limit and there
>> is serial33 alias poiting to uartlite (for example) then you don't want
>> to break this call for that.
>>
>> What can be done is that compatible string is checked first and if this
>> passed then ids are check and error can be returned or bit sets.
> 
> That's what I meant: currently any serialN with N >= nbits is ignored, even
> if the alias applies to the driver that called the function.

ok. Let me create a patch and check compatible string first and then
setup bit or fail if N >= nbits.

Thanks,
Michal
Michal Simek Oct. 8, 2018, 12:19 p.m. UTC | #5 
Hi Geert,

On 27.9.2018 09:22, Michal Simek wrote:
> On 27.9.2018 09:19, Geert Uytterhoeven wrote:
>> Hi Michal,
>>
>> On Wed, Sep 26, 2018 at 1:01 PM Michal Simek <michal.simek@xilinx.com> wrote:
>>> On 24.9.2018 09:41, Geert Uytterhoeven wrote:
>>>> On Thu, Sep 20, 2018 at 1:42 PM Michal Simek <michal.simek@xilinx.com> wrote:
>>>>> The function travels the lookup table to record alias ids for the given
>>>>> device match structures and alias stem.
>>>>> This function will be used by serial drivers to check if requested alias
>>>>> is allocated or free to use.
>>>>>
>>>>> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
>>>>> Reviewed-by: Rob Herring <robh@kernel.org>
>>>>
>>>> I know this has already been applied, it just drew my attention.
>>>>
>>>>> --- a/drivers/of/base.c
>>>>> +++ b/drivers/of/base.c
>>>>> @@ -16,6 +16,7 @@
>>>>>
>>>>>  #define pr_fmt(fmt)    "OF: " fmt
>>>>>
>>>>> +#include <linux/bitmap.h>
>>>>>  #include <linux/console.h>
>>>>>  #include <linux/ctype.h>
>>>>>  #include <linux/cpu.h>
>>>>> @@ -1943,6 +1944,57 @@ int of_alias_get_id(struct device_node *np, const char *stem)
>>>>>  EXPORT_SYMBOL_GPL(of_alias_get_id);
>>>>>
>>>>>  /**
>>>>> + * of_alias_get_alias_list - Get alias list for the given device driver
>>>>> + * @matches:   Array of OF device match structures to search in
>>>>> + * @stem:      Alias stem of the given device_node
>>>>> + * @bitmap:    Bitmap field pointer
>>>>> + * @nbits:     Maximum number of alias ID which can be recorded it bitmap
>>>>
>>>> IDs
>>>>
>>>>> + *
>>>>> + * The function travels the lookup table to record alias ids for the given
>>>>> + * device match structures and alias stem.
>>>>> + *
>>>>> + * Return:     0 or -ENOSYS when !CONFIG_OF
>>>>> + */
>>>>> +int of_alias_get_alias_list(const struct of_device_id *matches,
>>>>> +                            const char *stem, unsigned long *bitmap,
>>>>> +                            unsigned int nbits)
>>>>> +{
>>>>> +       struct alias_prop *app;
>>>>> +
>>>>> +       /* Zero bitmap field to make sure that all the time it is clean */
>>>>> +       bitmap_zero(bitmap, nbits);
>>>>> +
>>>>> +       mutex_lock(&of_mutex);
>>>>> +       pr_debug("%s: Looking for stem: %s\n", __func__, stem);
>>>>> +       list_for_each_entry(app, &aliases_lookup, link) {
>>>>> +               pr_debug("%s: stem: %s, id: %d\n",
>>>>> +                        __func__, app->stem, app->id);
>>>>> +
>>>>> +               if (strcmp(app->stem, stem) != 0) {
>>>>> +                       pr_debug("%s: stem comparison doesn't passed %s\n",
>>>>
>>>> didn't pass?
>>>>
>>>>> +                                __func__, app->stem);
>>>>> +                       continue;
>>>>> +               }
>>>>> +
>>>>> +               if (app->id >= nbits) {
>>>>> +                       pr_debug("%s: ID %d greater then bitmap field %d\n",
>>>>
>>>> than
>>>> %u for unsigned int
>>>
>>> I won't fix this now because this can be done together with one change
>>> described below.
>>>
>>>>
>>>>> +                               __func__, app->id, nbits);
>>>>> +                       continue;
>>>>
>>>> Shouldn't this return an error, if of_match_node() below would have matched?
>>>
>>> IIRC Above check is for "serial" name.
>>> This one is for getting XX number from alias "serialXX".
>>> And below is checking compatible string.
>>>
>>> You are calling this function from uartps with 32 lines limit and there
>>> is serial33 alias poiting to uartlite (for example) then you don't want
>>> to break this call for that.
>>>
>>> What can be done is that compatible string is checked first and if this
>>> passed then ids are check and error can be returned or bit sets.
>>
>> That's what I meant: currently any serialN with N >= nbits is ignored, even
>> if the alias applies to the driver that called the function.
> 
> ok. Let me create a patch and check compatible string first and then
> setup bit or fail if N >= nbits.

I have sent a patch with this change. Let's have discussion in that new
thread.

Thanks,
Michal
diff mbox series

Patch

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 74eaedd5b860..33011b88ed3f 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -16,6 +16,7 @@ 
 
 #define pr_fmt(fmt)	"OF: " fmt
 
+#include <linux/bitmap.h>
 #include <linux/console.h>
 #include <linux/ctype.h>
 #include <linux/cpu.h>
@@ -1943,6 +1944,57 @@  int of_alias_get_id(struct device_node *np, const char *stem)
 EXPORT_SYMBOL_GPL(of_alias_get_id);
 
 /**
+ * of_alias_get_alias_list - Get alias list for the given device driver
+ * @matches:	Array of OF device match structures to search in
+ * @stem:	Alias stem of the given device_node
+ * @bitmap:	Bitmap field pointer
+ * @nbits:	Maximum number of alias ID which can be recorded it bitmap
+ *
+ * The function travels the lookup table to record alias ids for the given
+ * device match structures and alias stem.
+ *
+ * Return:	0 or -ENOSYS when !CONFIG_OF
+ */
+int of_alias_get_alias_list(const struct of_device_id *matches,
+			     const char *stem, unsigned long *bitmap,
+			     unsigned int nbits)
+{
+	struct alias_prop *app;
+
+	/* Zero bitmap field to make sure that all the time it is clean */
+	bitmap_zero(bitmap, nbits);
+
+	mutex_lock(&of_mutex);
+	pr_debug("%s: Looking for stem: %s\n", __func__, stem);
+	list_for_each_entry(app, &aliases_lookup, link) {
+		pr_debug("%s: stem: %s, id: %d\n",
+			 __func__, app->stem, app->id);
+
+		if (strcmp(app->stem, stem) != 0) {
+			pr_debug("%s: stem comparison doesn't passed %s\n",
+				 __func__, app->stem);
+			continue;
+		}
+
+		if (app->id >= nbits) {
+			pr_debug("%s: ID %d greater then bitmap field %d\n",
+				__func__, app->id, nbits);
+			continue;
+		}
+
+		if (of_match_node(matches, app->np)) {
+			pr_debug("%s: Allocated ID %d\n", __func__, app->id);
+			set_bit(app->id, bitmap);
+		}
+		/* Alias exist but it not compatible with matches */
+	}
+	mutex_unlock(&of_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_alias_get_alias_list);
+
+/**
  * of_alias_get_highest_id - Get highest alias id for the given stem
  * @stem:	Alias stem to be examined
  *
diff --git a/include/linux/of.h b/include/linux/of.h
index 99b0ebf49632..d51457b40725 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -392,6 +392,9 @@  extern int of_phandle_iterator_args(struct of_phandle_iterator *it,
 extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
 extern int of_alias_get_id(struct device_node *np, const char *stem);
 extern int of_alias_get_highest_id(const char *stem);
+extern int of_alias_get_alias_list(const struct of_device_id *matches,
+				   const char *stem, unsigned long *bitmap,
+				   unsigned int nbits);
 
 extern int of_machine_is_compatible(const char *compat);
 
@@ -893,6 +896,13 @@  static inline int of_alias_get_highest_id(const char *stem)
 	return -ENOSYS;
 }
 
+static inline int of_alias_get_alias_list(const struct of_device_id *matches,
+					  const char *stem, unsigned long *bitmap,
+					  unsigned int nbits)
+{
+	return -ENOSYS;
+}
+
 static inline int of_machine_is_compatible(const char *compat)
 {
 	return 0;