2011-02-16 22:28:28

by Daniel Drake

[permalink] [raw]
Subject: [PATCH v3] olpc_battery: convert to platform device

This is needed so that suspend/resume (wakeup) support can be added.

Signed-off-by: Daniel Drake <[email protected]>
---
arch/x86/platform/olpc/olpc.c | 15 +++++++++++
drivers/power/olpc_battery.c | 53 +++++++++++++++++++++++-----------------
2 files changed, 45 insertions(+), 23 deletions(-)

v2: add MODULE_ALIAS thanks to Dmitry Torokhov

v3: fix __devexit annotation thanks to Dmitry

diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
index edaf3fe..a5fb933 100644
--- a/arch/x86/platform/olpc/olpc.c
+++ b/arch/x86/platform/olpc/olpc.c
@@ -239,6 +239,17 @@ static int __init add_xo1_platform_devices(void)
return 0;
}

+static int __init add_common_platform_devices(void)
+{
+ struct platform_device *pdev;
+
+ pdev = platform_device_register_simple("olpc-battery", -1, NULL, 0);
+ if (IS_ERR(pdev))
+ return PTR_ERR(pdev);
+
+ return 0;
+}
+
static int __init olpc_init(void)
{
int r = 0;
@@ -269,6 +280,10 @@ static int __init olpc_init(void)
olpc_platform_info.boardrev >> 4,
olpc_platform_info.ecver);

+ r = add_common_platform_devices();
+ if (r)
+ return r;
+
if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */
r = add_xo1_platform_devices();
if (r)
diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
index 0b0ff3a..18580b4 100644
--- a/drivers/power/olpc_battery.c
+++ b/drivers/power/olpc_battery.c
@@ -519,8 +519,6 @@ static struct device_attribute olpc_bat_error = {
* Initialisation
*********************************************************************/

-static struct platform_device *bat_pdev;
-
static struct power_supply olpc_bat = {
.get_property = olpc_bat_get_property,
.use_for_apm = 1,
@@ -534,14 +532,11 @@ void olpc_battery_trigger_uevent(unsigned long cause)
kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
}

-static int __init olpc_bat_init(void)
+static int __devinit olpc_battery_probe(struct platform_device *pdev)
{
- int ret = 0;
+ int ret;
uint8_t status;

- if (!olpc_platform_info.ecver)
- return -ENXIO;
-
/*
* We've seen a number of EC protocol changes; this driver requires
* the latest EC protocol, supported by 0x44 and above.
@@ -552,21 +547,16 @@ static int __init olpc_bat_init(void)
return -ENXIO;
}

+ /* Ignore the status. It doesn't actually matter */
ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
if (ret)
return ret;

- /* Ignore the status. It doesn't actually matter */
-
- bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
- if (IS_ERR(bat_pdev))
- return PTR_ERR(bat_pdev);
-
- ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
+ ret = power_supply_register(&pdev->dev, &olpc_ac);
if (ret)
- goto ac_failed;
+ return ret;

- olpc_bat.name = bat_pdev->name;
+ olpc_bat.name = pdev->name;
if (olpc_board_at_least(olpc_board_pre(0xd0))) { /* XO-1.5 */
olpc_bat.properties = olpc_xo15_bat_props;
olpc_bat.num_properties = ARRAY_SIZE(olpc_xo15_bat_props);
@@ -575,7 +565,7 @@ static int __init olpc_bat_init(void)
olpc_bat.num_properties = ARRAY_SIZE(olpc_xo1_bat_props);
}

- ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
+ ret = power_supply_register(&pdev->dev, &olpc_bat);
if (ret)
goto battery_failed;

@@ -587,7 +577,7 @@ static int __init olpc_bat_init(void)
if (ret)
goto error_failed;

- goto success;
+ return 0;

error_failed:
device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
@@ -595,19 +585,35 @@ eeprom_failed:
power_supply_unregister(&olpc_bat);
battery_failed:
power_supply_unregister(&olpc_ac);
-ac_failed:
- platform_device_unregister(bat_pdev);
-success:
return ret;
}

-static void __exit olpc_bat_exit(void)
+static int __devexit olpc_battery_remove(struct platform_device *pdev)
{
device_remove_file(olpc_bat.dev, &olpc_bat_error);
device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
power_supply_unregister(&olpc_bat);
power_supply_unregister(&olpc_ac);
- platform_device_unregister(bat_pdev);
+ return 0;
+}
+
+static struct platform_driver olpc_battery_drv = {
+ .driver = {
+ .name = "olpc-battery",
+ .owner = THIS_MODULE,
+ },
+ .probe = olpc_battery_probe,
+ .remove = __devexit_p(olpc_battery_remove),
+};
+
+static int __init olpc_bat_init(void)
+{
+ return platform_driver_register(&olpc_battery_drv);
+}
+
+static void __exit olpc_bat_exit(void)
+{
+ platform_driver_unregister(&olpc_battery_drv);
}

module_init(olpc_bat_init);
@@ -616,3 +622,4 @@ module_exit(olpc_bat_exit);
MODULE_AUTHOR("David Woodhouse <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");
+MODULE_ALIAS("platform:olpc-battery");
--
1.7.4


2011-02-16 22:34:49

by Dmitry Torokhov

[permalink] [raw]
Subject: Re: [PATCH v3] olpc_battery: convert to platform device

On Wed, Feb 16, 2011 at 10:28:20PM +0000, Daniel Drake wrote:
> This is needed so that suspend/resume (wakeup) support can be added.
>
> Signed-off-by: Daniel Drake <[email protected]>
> ---
> arch/x86/platform/olpc/olpc.c | 15 +++++++++++
> drivers/power/olpc_battery.c | 53 +++++++++++++++++++++++-----------------
> 2 files changed, 45 insertions(+), 23 deletions(-)
>
> v2: add MODULE_ALIAS thanks to Dmitry Torokhov
>
> v3: fix __devexit annotation thanks to Dmitry
>

Looks good to me, thank you for making the changes.

Reviewed-by: Dmitry Torohkov <[email protected]>

> diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
> index edaf3fe..a5fb933 100644
> --- a/arch/x86/platform/olpc/olpc.c
> +++ b/arch/x86/platform/olpc/olpc.c
> @@ -239,6 +239,17 @@ static int __init add_xo1_platform_devices(void)
> return 0;
> }
>
> +static int __init add_common_platform_devices(void)
> +{
> + struct platform_device *pdev;
> +
> + pdev = platform_device_register_simple("olpc-battery", -1, NULL, 0);
> + if (IS_ERR(pdev))
> + return PTR_ERR(pdev);
> +
> + return 0;
> +}
> +
> static int __init olpc_init(void)
> {
> int r = 0;
> @@ -269,6 +280,10 @@ static int __init olpc_init(void)
> olpc_platform_info.boardrev >> 4,
> olpc_platform_info.ecver);
>
> + r = add_common_platform_devices();
> + if (r)
> + return r;
> +
> if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */
> r = add_xo1_platform_devices();
> if (r)
> diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
> index 0b0ff3a..18580b4 100644
> --- a/drivers/power/olpc_battery.c
> +++ b/drivers/power/olpc_battery.c
> @@ -519,8 +519,6 @@ static struct device_attribute olpc_bat_error = {
> * Initialisation
> *********************************************************************/
>
> -static struct platform_device *bat_pdev;
> -
> static struct power_supply olpc_bat = {
> .get_property = olpc_bat_get_property,
> .use_for_apm = 1,
> @@ -534,14 +532,11 @@ void olpc_battery_trigger_uevent(unsigned long cause)
> kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
> }
>
> -static int __init olpc_bat_init(void)
> +static int __devinit olpc_battery_probe(struct platform_device *pdev)
> {
> - int ret = 0;
> + int ret;
> uint8_t status;
>
> - if (!olpc_platform_info.ecver)
> - return -ENXIO;
> -
> /*
> * We've seen a number of EC protocol changes; this driver requires
> * the latest EC protocol, supported by 0x44 and above.
> @@ -552,21 +547,16 @@ static int __init olpc_bat_init(void)
> return -ENXIO;
> }
>
> + /* Ignore the status. It doesn't actually matter */
> ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
> if (ret)
> return ret;
>
> - /* Ignore the status. It doesn't actually matter */
> -
> - bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
> - if (IS_ERR(bat_pdev))
> - return PTR_ERR(bat_pdev);
> -
> - ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
> + ret = power_supply_register(&pdev->dev, &olpc_ac);
> if (ret)
> - goto ac_failed;
> + return ret;
>
> - olpc_bat.name = bat_pdev->name;
> + olpc_bat.name = pdev->name;
> if (olpc_board_at_least(olpc_board_pre(0xd0))) { /* XO-1.5 */
> olpc_bat.properties = olpc_xo15_bat_props;
> olpc_bat.num_properties = ARRAY_SIZE(olpc_xo15_bat_props);
> @@ -575,7 +565,7 @@ static int __init olpc_bat_init(void)
> olpc_bat.num_properties = ARRAY_SIZE(olpc_xo1_bat_props);
> }
>
> - ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
> + ret = power_supply_register(&pdev->dev, &olpc_bat);
> if (ret)
> goto battery_failed;
>
> @@ -587,7 +577,7 @@ static int __init olpc_bat_init(void)
> if (ret)
> goto error_failed;
>
> - goto success;
> + return 0;
>
> error_failed:
> device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
> @@ -595,19 +585,35 @@ eeprom_failed:
> power_supply_unregister(&olpc_bat);
> battery_failed:
> power_supply_unregister(&olpc_ac);
> -ac_failed:
> - platform_device_unregister(bat_pdev);
> -success:
> return ret;
> }
>
> -static void __exit olpc_bat_exit(void)
> +static int __devexit olpc_battery_remove(struct platform_device *pdev)
> {
> device_remove_file(olpc_bat.dev, &olpc_bat_error);
> device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
> power_supply_unregister(&olpc_bat);
> power_supply_unregister(&olpc_ac);
> - platform_device_unregister(bat_pdev);
> + return 0;
> +}
> +
> +static struct platform_driver olpc_battery_drv = {
> + .driver = {
> + .name = "olpc-battery",
> + .owner = THIS_MODULE,
> + },
> + .probe = olpc_battery_probe,
> + .remove = __devexit_p(olpc_battery_remove),
> +};
> +
> +static int __init olpc_bat_init(void)
> +{
> + return platform_driver_register(&olpc_battery_drv);
> +}
> +
> +static void __exit olpc_bat_exit(void)
> +{
> + platform_driver_unregister(&olpc_battery_drv);
> }
>
> module_init(olpc_bat_init);
> @@ -616,3 +622,4 @@ module_exit(olpc_bat_exit);
> MODULE_AUTHOR("David Woodhouse <[email protected]>");
> MODULE_LICENSE("GPL");
> MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");
> +MODULE_ALIAS("platform:olpc-battery");
> --
> 1.7.4
>

--
Dmitry

2011-02-16 22:44:46

by David Woodhouse

[permalink] [raw]
Subject: Re: [PATCH v3] olpc_battery: convert to platform device

On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
>
> +static int __init add_common_platform_devices(void)
> +{
> + struct platform_device *pdev;
> +
> + pdev = platform_device_register_simple("olpc-battery", -1, NULL, 0);
> + if (IS_ERR(pdev))
> + return PTR_ERR(pdev);
> +
> + return 0;
> +}
> +

Still kind of sucks that you have to do this, and can't bind to
something in the device-tree.

--
David Woodhouse Open Source Technology Centre
[email protected] Intel Corporation

2011-02-16 23:41:18

by H. Peter Anvin

[permalink] [raw]
Subject: Re: [PATCH v3] olpc_battery: convert to platform device

On 02/16/2011 02:44 PM, David Woodhouse wrote:
> On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
>>
>> +static int __init add_common_platform_devices(void)
>> +{
>> + struct platform_device *pdev;
>> +
>> + pdev = platform_device_register_simple("olpc-battery", -1, NULL, 0);
>> + if (IS_ERR(pdev))
>> + return PTR_ERR(pdev);
>> +
>> + return 0;
>> +}
>> +
>
> Still kind of sucks that you have to do this, and can't bind to
> something in the device-tree.
>

Any reason you can't include a device tree in the OLPC kernel?

-hpa

2011-02-18 23:43:00

by Daniel Drake

[permalink] [raw]
Subject: Re: [PATCH v3] olpc_battery: convert to platform device

On 16 February 2011 22:44, David Woodhouse <[email protected]> wrote:
> On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
>>
>> +static int __init add_common_platform_devices(void)
>> +{
>> + ? ? ? struct platform_device *pdev;
>> +
>> + ? ? ? pdev = platform_device_register_simple("olpc-battery", -1, NULL, 0);
>> + ? ? ? if (IS_ERR(pdev))
>> + ? ? ? ? ? ? ? return PTR_ERR(pdev);
>> +
>> + ? ? ? return 0;
>> +}
>> +
>
> Still kind of sucks that you have to do this, and can't bind to
> something in the device-tree.

OK, feel free to put this patch on hold for now. I started looking at
the device tree approach today. It looks doable but first we have to
fix a DT bug/inconsistency that is preventing us from correctly
binding to the tree's devices.

Daniel

2011-02-19 03:07:08

by Andres Salomon

[permalink] [raw]
Subject: [PATCH] of/pdt: allow DT device matching by fixing 'name' brokenness

On Fri, 18 Feb 2011 23:42:57 +0000
Daniel Drake <[email protected]> wrote:

> On 16 February 2011 22:44, David Woodhouse <[email protected]>
> wrote:
> > On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
> >>
> >> +static int __init add_common_platform_devices(void)
> >> +{
> >> +       struct platform_device *pdev;
> >> +
> >> +       pdev = platform_device_register_simple("olpc-battery", -1,
> >> NULL, 0);
> >> +       if (IS_ERR(pdev))
> >> +               return PTR_ERR(pdev);
> >> +
> >> +       return 0;
> >> +}
> >> +
> >
> > Still kind of sucks that you have to do this, and can't bind to
> > something in the device-tree.
>
> OK, feel free to put this patch on hold for now. I started looking at
> the device tree approach today. It looks doable but first we have to
> fix a DT bug/inconsistency that is preventing us from correctly
> binding to the tree's devices.
>
> Daniel


Mea culpa. The patch below fixes a bug I introduced earlier.
Cc'ing the sparc folks, as this probably affects them
(although I would think that it fixes broken behavior for them..?)





From: Andres Salomon <[email protected]>

Commit e2f2a93b changed dp->name from using the 'name' property to
using package-to-path. This fixed /proc/device-tree creation by
eliminating conflicts between names (the 'name' property provides
names like 'battery', whereas package-to-path provides names like
'/foo/bar/battery@0', which we stripped to 'battery@0'). However,
it also breaks of_device_id table matching.

The fix that we _really_ wanted was to keep dp->name based upon
the name property ('battery'), but based dp->full_name upon
package-to-path ('battery@0'). This patch does just that.

Signed-off-by: Andres Salomon <[email protected]>
Reported-by: Daniel Drake <[email protected]>
---
drivers/of/pdt.c | 42 +++++++++++++++++++-----------------------
1 files changed, 19 insertions(+), 23 deletions(-)

diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
index 28295d0..b39d584 100644
--- a/drivers/of/pdt.c
+++ b/drivers/of/pdt.c
@@ -48,7 +48,7 @@ static inline void irq_trans_init(struct device_node *dp) { }

static inline const char *of_pdt_node_name(struct device_node *dp)
{
- return dp->name;
+ return NULL;
}

#endif /* !CONFIG_SPARC */
@@ -156,23 +156,6 @@ static char * __init of_pdt_try_pkg2path(phandle node)
return res+1;
}

-/*
- * When fetching the node's name, first try using package-to-path; if
- * that fails (either because the arch hasn't supplied a PROM callback,
- * or some other random failure), fall back to just looking at the node's
- * 'name' property.
- */
-static char * __init of_pdt_build_name(phandle node)
-{
- char *buf;
-
- buf = of_pdt_try_pkg2path(node);
- if (!buf)
- buf = of_pdt_get_one_property(node, "name");
-
- return buf;
-}
-
static struct device_node * __init of_pdt_create_node(phandle node,
struct device_node *parent)
{
@@ -187,7 +170,7 @@ static struct device_node * __init of_pdt_create_node(phandle node,

kref_init(&dp->kref);

- dp->name = of_pdt_build_name(node);
+ dp->name = of_pdt_get_one_property(node, "name");
dp->type = of_pdt_get_one_property(node, "device_type");
dp->phandle = node;

@@ -198,13 +181,26 @@ static struct device_node * __init of_pdt_create_node(phandle node,
return dp;
}

-static char * __init of_pdt_build_full_name(struct device_node *dp)
+static char * __init of_pdt_build_full_name(struct device_node *dp,
+ phandle node)
{
int len, ourlen, plen;
+ const char *name;
char *n;

+ /*
+ * When fetching the full name, rather than what we see with the
+ * name property (ie, 'battery'), we want the name we see with
+ * package-to-path (ie, 'battery@0').
+ */
+ name = of_pdt_node_name(dp);
+ if (!name)
+ name = of_pdt_try_pkg2path(node);
+ if (!name)
+ name = dp->name;
+
plen = strlen(dp->parent->full_name);
- ourlen = strlen(of_pdt_node_name(dp));
+ ourlen = strlen(name);
len = ourlen + plen + 2;

n = prom_early_alloc(len);
@@ -213,7 +209,7 @@ static char * __init of_pdt_build_full_name(struct device_node *dp)
strcpy(n + plen, "/");
plen++;
}
- strcpy(n + plen, of_pdt_node_name(dp));
+ strcpy(n + plen, name);

return n;
}
@@ -243,7 +239,7 @@ static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
#if defined(CONFIG_SPARC)
dp->path_component_name = build_path_component(dp);
#endif
- dp->full_name = of_pdt_build_full_name(dp);
+ dp->full_name = of_pdt_build_full_name(dp, node);

dp->child = of_pdt_build_tree(dp,
of_pdt_prom_ops->getchild(node), nextp);
--
1.7.2.3

2011-02-19 03:12:32

by Andres Salomon

[permalink] [raw]
Subject: [PATCH] of/pdt: don't bother parsing pkg2path results, return as-is

On Fri, 18 Feb 2011 19:06:59 -0800
Andres Salomon <[email protected]> wrote:

> On Fri, 18 Feb 2011 23:42:57 +0000
> Daniel Drake <[email protected]> wrote:
>
> > On 16 February 2011 22:44, David Woodhouse <[email protected]>
> > wrote:
> > > On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
> > >>
> > >> +static int __init add_common_platform_devices(void)
> > >> +{
> > >> +       struct platform_device *pdev;
> > >> +
> > >> +       pdev = platform_device_register_simple("olpc-battery",
> > >> -1, NULL, 0);
> > >> +       if (IS_ERR(pdev))
> > >> +               return PTR_ERR(pdev);
> > >> +
> > >> +       return 0;
> > >> +}
> > >> +
> > >
> > > Still kind of sucks that you have to do this, and can't bind to
> > > something in the device-tree.
> >
> > OK, feel free to put this patch on hold for now. I started looking
> > at the device tree approach today. It looks doable but first we
> > have to fix a DT bug/inconsistency that is preventing us from
> > correctly binding to the tree's devices.
> >
> > Daniel
>
>
> Mea culpa. The patch below fixes a bug I introduced earlier.
> Cc'ing the sparc folks, as this probably affects them
> (although I would think that it fixes broken behavior for them..?)
>
>
>

And this is a followup to the prior patch; an optimization based
upon what we're doing with pkg2path stuff.

The sparc folks don't use pkg2path, so this shouldn't affect them at
all.

Cc'ing Mitch as well, in case there's some reason why I should be
wary of doing this. :)




From: Andres Salomon <[email protected]>

The of_pdt_try_pkg2path() function currently allocates memory for
and fetches the full path name from OFW (of the form '/foo/bar/baz@0').
It then returns only the name ('baz@0)', and the caller re-constructs
the full name (for dp->full_name) based upon dp->parent->full_name and
what was returned by of_pdt_try_pkg2path(). Oh, and it allocates more
memory for it.

OLPC is the only architecture which fills in the pkg2path hook, so
this shouldn't affect any other users (ie, sparc). Since in practice
(dp->parent->full_name + '/' + strrchr(pkg2path, '/')) and the result
from pkg2path end up being exactly the same, just short circuit the rest
of the of_pdt_build_full_name logic and set dp->full_name to the result
of pkg2path. This means we don't have to parse it nor allocate more
memory for it.

This saves time, code, and memory.

Signed-off-by: Andres Salomon <[email protected]>
---
drivers/of/pdt.c | 17 +++++++----------
1 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
index b39d584..605834b 100644
--- a/drivers/of/pdt.c
+++ b/drivers/of/pdt.c
@@ -134,7 +134,7 @@ static char * __init of_pdt_get_one_property(phandle node, const char *name)

static char * __init of_pdt_try_pkg2path(phandle node)
{
- char *res, *buf = NULL;
+ char *buf = NULL;
int len;

if (!of_pdt_prom_ops->pkg2path)
@@ -147,13 +147,7 @@ static char * __init of_pdt_try_pkg2path(phandle node)
pr_err("%s: package-to-path failed\n", __func__);
return NULL;
}
-
- res = strrchr(buf, '/');
- if (!res) {
- pr_err("%s: couldn't find / in %s\n", __func__, buf);
- return NULL;
- }
- return res+1;
+ return buf;
}

static struct device_node * __init of_pdt_create_node(phandle node,
@@ -193,10 +187,13 @@ static char * __init of_pdt_build_full_name(struct device_node *dp,
* name property (ie, 'battery'), we want the name we see with
* package-to-path (ie, 'battery@0').
*/
+ n = of_pdt_try_pkg2path(node);
+ if (n)
+ return n;
+
+ /* Older methods for determining full name */
name = of_pdt_node_name(dp);
if (!name)
- name = of_pdt_try_pkg2path(node);
- if (!name)
name = dp->name;

plen = strlen(dp->parent->full_name);
--
1.7.2.3

2011-02-23 19:44:01

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH] of/pdt: allow DT device matching by fixing 'name' brokenness

On Fri, Feb 18, 2011 at 07:06:59PM -0800, Andres Salomon wrote:
> On Fri, 18 Feb 2011 23:42:57 +0000
> Daniel Drake <[email protected]> wrote:
>
> > On 16 February 2011 22:44, David Woodhouse <[email protected]>
> > wrote:
> > > On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
> > >>
> > >> +static int __init add_common_platform_devices(void)
> > >> +{
> > >> + ? ? ? struct platform_device *pdev;
> > >> +
> > >> + ? ? ? pdev = platform_device_register_simple("olpc-battery", -1,
> > >> NULL, 0);
> > >> + ? ? ? if (IS_ERR(pdev))
> > >> + ? ? ? ? ? ? ? return PTR_ERR(pdev);
> > >> +
> > >> + ? ? ? return 0;
> > >> +}
> > >> +
> > >
> > > Still kind of sucks that you have to do this, and can't bind to
> > > something in the device-tree.
> >
> > OK, feel free to put this patch on hold for now. I started looking at
> > the device tree approach today. It looks doable but first we have to
> > fix a DT bug/inconsistency that is preventing us from correctly
> > binding to the tree's devices.
> >
> > Daniel
>
>
> Mea culpa. The patch below fixes a bug I introduced earlier.
> Cc'ing the sparc folks, as this probably affects them
> (although I would think that it fixes broken behavior for them..?)

Wait; why are you binding to a device based on name? Binding by name
and/or device_type is strongly discouraged for new code. Use compatible
instead.

As for this patch, comments below...

> From: Andres Salomon <[email protected]>
>
> Commit e2f2a93b changed dp->name from using the 'name' property to
> using package-to-path. This fixed /proc/device-tree creation by
> eliminating conflicts between names (the 'name' property provides
> names like 'battery', whereas package-to-path provides names like
> '/foo/bar/battery@0', which we stripped to 'battery@0'). However,
> it also breaks of_device_id table matching.
>
> The fix that we _really_ wanted was to keep dp->name based upon
> the name property ('battery'), but based dp->full_name upon
> package-to-path ('battery@0'). This patch does just that.
>
> Signed-off-by: Andres Salomon <[email protected]>
> Reported-by: Daniel Drake <[email protected]>

>From what I can tell, this only affects OLPC, correct? It looks like
SPARC's implementation of of_pdt_node_name() will sidestep most of this
name retrieval code.

> ---
> drivers/of/pdt.c | 42 +++++++++++++++++++-----------------------
> 1 files changed, 19 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
> index 28295d0..b39d584 100644
> --- a/drivers/of/pdt.c
> +++ b/drivers/of/pdt.c
> @@ -48,7 +48,7 @@ static inline void irq_trans_init(struct device_node *dp) { }
>
> static inline const char *of_pdt_node_name(struct device_node *dp)
> {
> - return dp->name;
> + return NULL;
> }

Rather than using this hook; perhaps the sparc .path_component_name
should be enabled for all architectures. It is a useful data item to
keep a pointer to, and it would simplify the of_pdt code.

>
> #endif /* !CONFIG_SPARC */
> @@ -156,23 +156,6 @@ static char * __init of_pdt_try_pkg2path(phandle node)
> return res+1;
> }
>
> -/*
> - * When fetching the node's name, first try using package-to-path; if
> - * that fails (either because the arch hasn't supplied a PROM callback,
> - * or some other random failure), fall back to just looking at the node's
> - * 'name' property.
> - */
> -static char * __init of_pdt_build_name(phandle node)
> -{
> - char *buf;
> -
> - buf = of_pdt_try_pkg2path(node);
> - if (!buf)
> - buf = of_pdt_get_one_property(node, "name");
> -
> - return buf;
> -}
> -
> static struct device_node * __init of_pdt_create_node(phandle node,
> struct device_node *parent)
> {
> @@ -187,7 +170,7 @@ static struct device_node * __init of_pdt_create_node(phandle node,
>
> kref_init(&dp->kref);
>
> - dp->name = of_pdt_build_name(node);
> + dp->name = of_pdt_get_one_property(node, "name");
> dp->type = of_pdt_get_one_property(node, "device_type");
> dp->phandle = node;
>
> @@ -198,13 +181,26 @@ static struct device_node * __init of_pdt_create_node(phandle node,
> return dp;
> }
>
> -static char * __init of_pdt_build_full_name(struct device_node *dp)
> +static char * __init of_pdt_build_full_name(struct device_node *dp,
> + phandle node)
> {
> int len, ourlen, plen;
> + const char *name;
> char *n;
>
> + /*
> + * When fetching the full name, rather than what we see with the
> + * name property (ie, 'battery'), we want the name we see with
> + * package-to-path (ie, 'battery@0').
> + */
> + name = of_pdt_node_name(dp);
> + if (!name)
> + name = of_pdt_try_pkg2path(node);
> + if (!name)
> + name = dp->name;
> +

Rather than this thrashing about looking for a way to get the path
component, it should be fairly certain how to obtain the node's name
before getting into of_pdt_build_full_name(). I'd follow SPARC's
lead and create an implementation of build_path_component();

However, considering that this is creating the full name; wouldn't the
raw output of pkg2path() provide exactly the full name string you need
here instead of breaking it down into components and adding it back up
again?

> plen = strlen(dp->parent->full_name);
> - ourlen = strlen(of_pdt_node_name(dp));
> + ourlen = strlen(name);
> len = ourlen + plen + 2;
>
> n = prom_early_alloc(len);
> @@ -213,7 +209,7 @@ static char * __init of_pdt_build_full_name(struct device_node *dp)
> strcpy(n + plen, "/");
> plen++;
> }
> - strcpy(n + plen, of_pdt_node_name(dp));
> + strcpy(n + plen, name);
>
> return n;
> }
> @@ -243,7 +239,7 @@ static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
> #if defined(CONFIG_SPARC)
> dp->path_component_name = build_path_component(dp);
> #endif
> - dp->full_name = of_pdt_build_full_name(dp);
> + dp->full_name = of_pdt_build_full_name(dp, node);
>
> dp->child = of_pdt_build_tree(dp,
> of_pdt_prom_ops->getchild(node), nextp);
> --
> 1.7.2.3
>

2011-02-23 19:45:17

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH] of/pdt: don't bother parsing pkg2path results, return as-is

On Fri, Feb 18, 2011 at 07:12:25PM -0800, Andres Salomon wrote:
> On Fri, 18 Feb 2011 19:06:59 -0800
> Andres Salomon <[email protected]> wrote:
>
> > On Fri, 18 Feb 2011 23:42:57 +0000
> > Daniel Drake <[email protected]> wrote:
> >
> > > On 16 February 2011 22:44, David Woodhouse <[email protected]>
> > > wrote:
> > > > On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
> > > >>
> > > >> +static int __init add_common_platform_devices(void)
> > > >> +{
> > > >> + ? ? ? struct platform_device *pdev;
> > > >> +
> > > >> + ? ? ? pdev = platform_device_register_simple("olpc-battery",
> > > >> -1, NULL, 0);
> > > >> + ? ? ? if (IS_ERR(pdev))
> > > >> + ? ? ? ? ? ? ? return PTR_ERR(pdev);
> > > >> +
> > > >> + ? ? ? return 0;
> > > >> +}
> > > >> +
> > > >
> > > > Still kind of sucks that you have to do this, and can't bind to
> > > > something in the device-tree.
> > >
> > > OK, feel free to put this patch on hold for now. I started looking
> > > at the device tree approach today. It looks doable but first we
> > > have to fix a DT bug/inconsistency that is preventing us from
> > > correctly binding to the tree's devices.
> > >
> > > Daniel
> >
> >
> > Mea culpa. The patch below fixes a bug I introduced earlier.
> > Cc'ing the sparc folks, as this probably affects them
> > (although I would think that it fixes broken behavior for them..?)
> >
> >
> >
>
> And this is a followup to the prior patch; an optimization based
> upon what we're doing with pkg2path stuff.
>
> The sparc folks don't use pkg2path, so this shouldn't affect them at
> all.
>
> Cc'ing Mitch as well, in case there's some reason why I should be
> wary of doing this. :)
>
>
>
>
> From: Andres Salomon <[email protected]>
>
> The of_pdt_try_pkg2path() function currently allocates memory for
> and fetches the full path name from OFW (of the form '/foo/bar/baz@0').
> It then returns only the name ('baz@0)', and the caller re-constructs
> the full name (for dp->full_name) based upon dp->parent->full_name and
> what was returned by of_pdt_try_pkg2path(). Oh, and it allocates more
> memory for it.
>
> OLPC is the only architecture which fills in the pkg2path hook, so
> this shouldn't affect any other users (ie, sparc). Since in practice
> (dp->parent->full_name + '/' + strrchr(pkg2path, '/')) and the result
> from pkg2path end up being exactly the same, just short circuit the rest
> of the of_pdt_build_full_name logic and set dp->full_name to the result
> of pkg2path. This means we don't have to parse it nor allocate more
> memory for it.
>
> This saves time, code, and memory.
>
> Signed-off-by: Andres Salomon <[email protected]>
> ---
> drivers/of/pdt.c | 17 +++++++----------
> 1 files changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
> index b39d584..605834b 100644
> --- a/drivers/of/pdt.c
> +++ b/drivers/of/pdt.c
> @@ -134,7 +134,7 @@ static char * __init of_pdt_get_one_property(phandle node, const char *name)
>
> static char * __init of_pdt_try_pkg2path(phandle node)
> {
> - char *res, *buf = NULL;
> + char *buf = NULL;
> int len;
>
> if (!of_pdt_prom_ops->pkg2path)
> @@ -147,13 +147,7 @@ static char * __init of_pdt_try_pkg2path(phandle node)
> pr_err("%s: package-to-path failed\n", __func__);
> return NULL;
> }
> -
> - res = strrchr(buf, '/');
> - if (!res) {
> - pr_err("%s: couldn't find / in %s\n", __func__, buf);
> - return NULL;
> - }
> - return res+1;
> + return buf;
> }
>
> static struct device_node * __init of_pdt_create_node(phandle node,
> @@ -193,10 +187,13 @@ static char * __init of_pdt_build_full_name(struct device_node *dp,
> * name property (ie, 'battery'), we want the name we see with
> * package-to-path (ie, 'battery@0').
> */
> + n = of_pdt_try_pkg2path(node);
> + if (n)
> + return n;
> +
> + /* Older methods for determining full name */
> name = of_pdt_node_name(dp);
> if (!name)
> - name = of_pdt_try_pkg2path(node);
> - if (!name)

Ah, this addresses one of the comments I just made on the first patch.
I'd squash the two patches together before you repost.

g.

> name = dp->name;
>
> plen = strlen(dp->parent->full_name);
> --
> 1.7.2.3
>

2011-02-23 19:54:20

by Andres Salomon

[permalink] [raw]
Subject: Re: [PATCH] of/pdt: allow DT device matching by fixing 'name' brokenness

On Wed, 23 Feb 2011 12:43:52 -0700
Grant Likely <[email protected]> wrote:

> On Fri, Feb 18, 2011 at 07:06:59PM -0800, Andres Salomon wrote:
> > On Fri, 18 Feb 2011 23:42:57 +0000
> > Daniel Drake <[email protected]> wrote:
> >
> > > On 16 February 2011 22:44, David Woodhouse <[email protected]>
> > > wrote:
> > > > On Wed, 2011-02-16 at 22:28 +0000, Daniel Drake wrote:
> > > >>
> > > >> +static int __init add_common_platform_devices(void)
> > > >> +{
> > > >> +       struct platform_device *pdev;
> > > >> +
> > > >> +       pdev = platform_device_register_simple("olpc-battery",
> > > >> -1, NULL, 0);
> > > >> +       if (IS_ERR(pdev))
> > > >> +               return PTR_ERR(pdev);
> > > >> +
> > > >> +       return 0;
> > > >> +}
> > > >> +
> > > >
> > > > Still kind of sucks that you have to do this, and can't bind to
> > > > something in the device-tree.
> > >
> > > OK, feel free to put this patch on hold for now. I started
> > > looking at the device tree approach today. It looks doable but
> > > first we have to fix a DT bug/inconsistency that is preventing us
> > > from correctly binding to the tree's devices.
> > >
> > > Daniel
> >
> >
> > Mea culpa. The patch below fixes a bug I introduced earlier.
> > Cc'ing the sparc folks, as this probably affects them
> > (although I would think that it fixes broken behavior for them..?)
>
> Wait; why are you binding to a device based on name? Binding by name
> and/or device_type is strongly discouraged for new code. Use
> compatible instead.
>

Daniel posted a separate patch showing his code, would you mind
commenting on that? I noticed he didn't cc you though, here's the
patch:

https://patchwork.kernel.org/patch/574901/


> As for this patch, comments below...
>
> > From: Andres Salomon <[email protected]>
> >
> > Commit e2f2a93b changed dp->name from using the 'name' property to
> > using package-to-path. This fixed /proc/device-tree creation by
> > eliminating conflicts between names (the 'name' property provides
> > names like 'battery', whereas package-to-path provides names like
> > '/foo/bar/battery@0', which we stripped to 'battery@0'). However,
> > it also breaks of_device_id table matching.
> >
> > The fix that we _really_ wanted was to keep dp->name based upon
> > the name property ('battery'), but based dp->full_name upon
> > package-to-path ('battery@0'). This patch does just that.
> >
> > Signed-off-by: Andres Salomon <[email protected]>
> > Reported-by: Daniel Drake <[email protected]>
>
> From what I can tell, this only affects OLPC, correct? It looks like
> SPARC's implementation of of_pdt_node_name() will sidestep most of
> this name retrieval code.
>


This affects sparc as well; it changes behavior back for dp->name to
what it used to be. dp->full_name behavior is still the same for sparc.


> > ---
> > drivers/of/pdt.c | 42 +++++++++++++++++++-----------------------
> > 1 files changed, 19 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
> > index 28295d0..b39d584 100644
> > --- a/drivers/of/pdt.c
> > +++ b/drivers/of/pdt.c
> > @@ -48,7 +48,7 @@ static inline void irq_trans_init(struct
> > device_node *dp) { }
> > static inline const char *of_pdt_node_name(struct device_node *dp)
> > {
> > - return dp->name;
> > + return NULL;
> > }
>
> Rather than using this hook; perhaps the sparc .path_component_name
> should be enabled for all architectures. It is a useful data item to
> keep a pointer to, and it would simplify the of_pdt code.
>
> >

Yeah, I considered that, but pkg2path works even better for our
purposes.


I'll combine patches and resend, thanks.

2011-02-23 20:06:50

by Daniel Drake

[permalink] [raw]
Subject: Re: [PATCH] of/pdt: allow DT device matching by fixing 'name' brokenness

On 23 February 2011 19:54, Andres Salomon <[email protected]> wrote:
>> Wait; why are you binding to a device based on name? ?Binding by name
>> and/or device_type is strongly discouraged for new code. ?Use
>> compatible instead.
>>
>
> Daniel posted a separate patch showing his code, would you mind
> commenting on that? ?I noticed he didn't cc you though, here's the
> patch:
>
> https://patchwork.kernel.org/patch/574901/

It does bind to the name.
We don't currently have a compatible property for the battery device.
We could fix that with a firmware upgrade, but it would break
compatibility with all existing installs. I guess this is still the
recommended approach...

Daniel

2011-02-23 20:36:04

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH] of/pdt: allow DT device matching by fixing 'name' brokenness

On Wed, Feb 23, 2011 at 11:54:14AM -0800, Andres Salomon wrote:
> On Wed, 23 Feb 2011 12:43:52 -0700
> Grant Likely <[email protected]> wrote:
>
> > On Fri, Feb 18, 2011 at 07:06:59PM -0800, Andres Salomon wrote:
> > Wait; why are you binding to a device based on name? Binding by name
> > and/or device_type is strongly discouraged for new code. Use
> > compatible instead.
> >
>
> Daniel posted a separate patch showing his code, would you mind
> commenting on that? I noticed he didn't cc you though, here's the
> patch:
>
> https://patchwork.kernel.org/patch/574901/

Done.

g.

2011-02-23 20:37:23

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH] of/pdt: allow DT device matching by fixing 'name' brokenness

On Wed, Feb 23, 2011 at 08:06:47PM +0000, Daniel Drake wrote:
> On 23 February 2011 19:54, Andres Salomon <[email protected]> wrote:
> >> Wait; why are you binding to a device based on name? ?Binding by name
> >> and/or device_type is strongly discouraged for new code. ?Use
> >> compatible instead.
> >>
> >
> > Daniel posted a separate patch showing his code, would you mind
> > commenting on that? ?I noticed he didn't cc you though, here's the
> > patch:
> >
> > https://patchwork.kernel.org/patch/574901/
>
> It does bind to the name.
> We don't currently have a compatible property for the battery device.
> We could fix that with a firmware upgrade, but it would break
> compatibility with all existing installs. I guess this is still the
> recommended approach...

Hi Daniel,

As mentioned in my reply to your patch, the solution to this is fix up
the missing compatible property in the board support code before it
pollutes the global matching namespace.

g.