[PATCH] cpufreq: SPEAr: Instantiate as platform_driver

[PATCH] cpufreq: SPEAr: Instantiate as platform_driver

[Viresh Kumar]

As multiplatform build is being adopted by more and more ARM platforms, initcall
function should be used very carefully. For example, when SPEAr cpufreq driver
is enabled on a kernel booted on a non-SPEAr board, we will get following boot
time error:

	spear_cpufreq: Invalid cpufreq_tbl

To eliminate this undesired the effect, the patch changes SPEAr driver to have
it instantiated as a platform_driver. Then it will only run on platforms that
create the platform_device "spear-cpufreq".

This patch also creates platform node for SPEAr13xx boards.

Reported-by: Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 arch/arm/mach-spear/spear1310.c |  1 +
 arch/arm/mach-spear/spear1340.c |  1 +
 drivers/cpufreq/spear-cpufreq.c | 13 +++++++++++--
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-spear/spear1310.c b/arch/arm/mach-spear/spear1310.c
index 7ad0030..824b12a 100644
--- a/arch/arm/mach-spear/spear1310.c
+++ b/arch/arm/mach-spear/spear1310.c
@@ -28,6 +28,7 @@
 static void __init spear1310_dt_init(void)
 {
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+	platform_device_register_simple("spear-cpufreq", -1, NULL, 0);
 }
 
 static const char * const spear1310_dt_board_compat[] = {
diff --git a/arch/arm/mach-spear/spear1340.c b/arch/arm/mach-spear/spear1340.c
index 3fb6834..7b6bff7 100644
--- a/arch/arm/mach-spear/spear1340.c
+++ b/arch/arm/mach-spear/spear1340.c
@@ -143,6 +143,7 @@ static void __init spear1340_dt_init(void)
 {
 	of_platform_populate(NULL, of_default_bus_match_table,
 			spear1340_auxdata_lookup, NULL);
+	platform_device_register_simple("spear-cpufreq", -1, NULL, 0);
 }
 
 static const char * const spear1340_dt_board_compat[] = {
diff --git a/drivers/cpufreq/spear-cpufreq.c b/drivers/cpufreq/spear-cpufreq.c
index 410b54a..4cfdcff 100644
--- a/drivers/cpufreq/spear-cpufreq.c
+++ b/drivers/cpufreq/spear-cpufreq.c
@@ -19,6 +19,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
+#include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 
@@ -166,7 +167,7 @@ static struct cpufreq_driver spear_cpufreq_driver = {
 	.attr		= cpufreq_generic_attr,
 };
 
-static int spear_cpufreq_driver_init(void)
+static int spear_cpufreq_probe(struct platform_device *pdev)
 {
 	struct device_node *np;
 	const struct property *prop;
@@ -234,7 +235,15 @@ out_put_node:
 	of_node_put(np);
 	return ret;
 }
-late_initcall(spear_cpufreq_driver_init);
+
+static struct platform_driver spear_cpufreq_platdrv = {
+	.driver = {
+		.name	= "spear-cpufreq",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= spear_cpufreq_probe,
+};
+module_platform_driver(spear_cpufreq_platdrv);
 
 MODULE_AUTHOR("Deepak Sikri <deepak.sikri@st.com>");
 MODULE_DESCRIPTION("SPEAr CPUFreq driver");
-- 
1.7.12.rc2.18.g61b472e

Re: [PATCH] cpufreq: SPEAr: Instantiate as platform_driver

[Rafael J. Wysocki]

On Monday, March 10, 2014 03:43:18 PM Viresh Kumar wrote:
> As multiplatform build is being adopted by more and more ARM platforms, initcall
> function should be used very carefully. For example, when SPEAr cpufreq driver
> is enabled on a kernel booted on a non-SPEAr board, we will get following boot
> time error:
> 
> 	spear_cpufreq: Invalid cpufreq_tbl
> 
> To eliminate this undesired the effect, the patch changes SPEAr driver to have
> it instantiated as a platform_driver. Then it will only run on platforms that
> create the platform_device "spear-cpufreq".
> 
> This patch also creates platform node for SPEAr13xx boards.
> 
> Reported-by: Josh Cartwright <joshc@codeaurora.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Whoever maintains the SPEAr platform, I need an ACK from that person in order
to take this patch.

> ---
>  arch/arm/mach-spear/spear1310.c |  1 +
>  arch/arm/mach-spear/spear1340.c |  1 +
>  drivers/cpufreq/spear-cpufreq.c | 13 +++++++++++--
>  3 files changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/mach-spear/spear1310.c b/arch/arm/mach-spear/spear1310.c
> index 7ad0030..824b12a 100644
> --- a/arch/arm/mach-spear/spear1310.c
> +++ b/arch/arm/mach-spear/spear1310.c
> @@ -28,6 +28,7 @@
>  static void __init spear1310_dt_init(void)
>  {
>  	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
> +	platform_device_register_simple("spear-cpufreq", -1, NULL, 0);
>  }
>  
>  static const char * const spear1310_dt_board_compat[] = {
> diff --git a/arch/arm/mach-spear/spear1340.c b/arch/arm/mach-spear/spear1340.c
> index 3fb6834..7b6bff7 100644
> --- a/arch/arm/mach-spear/spear1340.c
> +++ b/arch/arm/mach-spear/spear1340.c
> @@ -143,6 +143,7 @@ static void __init spear1340_dt_init(void)
>  {
>  	of_platform_populate(NULL, of_default_bus_match_table,
>  			spear1340_auxdata_lookup, NULL);
> +	platform_device_register_simple("spear-cpufreq", -1, NULL, 0);
>  }
>  
>  static const char * const spear1340_dt_board_compat[] = {
> diff --git a/drivers/cpufreq/spear-cpufreq.c b/drivers/cpufreq/spear-cpufreq.c
> index 410b54a..4cfdcff 100644
> --- a/drivers/cpufreq/spear-cpufreq.c
> +++ b/drivers/cpufreq/spear-cpufreq.c
> @@ -19,6 +19,7 @@
>  #include <linux/init.h>
>  #include <linux/module.h>
>  #include <linux/of_device.h>
> +#include <linux/platform_device.h>
>  #include <linux/slab.h>
>  #include <linux/types.h>
>  
> @@ -166,7 +167,7 @@ static struct cpufreq_driver spear_cpufreq_driver = {
>  	.attr		= cpufreq_generic_attr,
>  };
>  
> -static int spear_cpufreq_driver_init(void)
> +static int spear_cpufreq_probe(struct platform_device *pdev)
>  {
>  	struct device_node *np;
>  	const struct property *prop;
> @@ -234,7 +235,15 @@ out_put_node:
>  	of_node_put(np);
>  	return ret;
>  }
> -late_initcall(spear_cpufreq_driver_init);
> +
> +static struct platform_driver spear_cpufreq_platdrv = {
> +	.driver = {
> +		.name	= "spear-cpufreq",
> +		.owner	= THIS_MODULE,
> +	},
> +	.probe		= spear_cpufreq_probe,
> +};
> +module_platform_driver(spear_cpufreq_platdrv);
>  
>  MODULE_AUTHOR("Deepak Sikri <deepak.sikri@st.com>");
>  MODULE_DESCRIPTION("SPEAr CPUFreq driver");
> 

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [PATCH] cpufreq: SPEAr: Instantiate as platform_driver

[Viresh Kumar]

On 11 March 2014 09:04, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> On Monday, March 10, 2014 03:43:18 PM Viresh Kumar wrote:
>> As multiplatform build is being adopted by more and more ARM platforms, initcall
>> function should be used very carefully. For example, when SPEAr cpufreq driver
>> is enabled on a kernel booted on a non-SPEAr board, we will get following boot
>> time error:
>>
>>       spear_cpufreq: Invalid cpufreq_tbl
>>
>> To eliminate this undesired the effect, the patch changes SPEAr driver to have
>> it instantiated as a platform_driver. Then it will only run on platforms that
>> create the platform_device "spear-cpufreq".
>>
>> This patch also creates platform node for SPEAr13xx boards.
>>
>> Reported-by: Josh Cartwright <joshc@codeaurora.org>
>> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
>
> Whoever maintains the SPEAr platform, I need an ACK from that person in order
> to take this patch.

Okay, here you go:

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

:)

Re: [PATCH] cpufreq: SPEAr: Instantiate as platform_driver

[Rafael J. Wysocki]

On Tuesday, March 11, 2014 11:46:22 AM Viresh Kumar wrote:
> On 11 March 2014 09:04, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> > On Monday, March 10, 2014 03:43:18 PM Viresh Kumar wrote:
> >> As multiplatform build is being adopted by more and more ARM platforms, initcall
> >> function should be used very carefully. For example, when SPEAr cpufreq driver
> >> is enabled on a kernel booted on a non-SPEAr board, we will get following boot
> >> time error:
> >>
> >>       spear_cpufreq: Invalid cpufreq_tbl
> >>
> >> To eliminate this undesired the effect, the patch changes SPEAr driver to have
> >> it instantiated as a platform_driver. Then it will only run on platforms that
> >> create the platform_device "spear-cpufreq".
> >>
> >> This patch also creates platform node for SPEAr13xx boards.
> >>
> >> Reported-by: Josh Cartwright <joshc@codeaurora.org>
> >> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> >
> > Whoever maintains the SPEAr platform, I need an ACK from that person in order
> > to take this patch.
> 
> Okay, here you go:
> 
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
> 
> :)

I see.  OK

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.