diff mbox

[4/4] drivers/bus: make arm-ccn.c driver explicitly non-modular

Message ID 1459113058-14340-5-git-send-email-paul.gortmaker@windriver.com (mailing list archive)
State New, archived
Headers show

Commit Message

Paul Gortmaker March 27, 2016, 9:10 p.m. UTC
The Kconfig for this driver is currently:

config ARM_CCN
        bool "ARM CCN driver support"

...meaning that it currently is not being built as a module by anyone.
Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

We explicitly disallow a driver unbind, since that doesn't have a
sensible use case anyway, and it allows us to drop the ".remove"
code for non-modular drivers.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We exchange module.h for moduleparam.h here since the driver uses
module_param_named, and for now the easiest way to remain compatible
with existing bootargs use cases is to leave this as-is.

We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.

Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
 drivers/bus/arm-ccn.c | 41 +++++------------------------------------
 1 file changed, 5 insertions(+), 36 deletions(-)

Comments

Will Deacon March 29, 2016, 11:45 a.m. UTC | #1
On Sun, Mar 27, 2016 at 05:10:58PM -0400, Paul Gortmaker wrote:
> The Kconfig for this driver is currently:
> 
> config ARM_CCN
>         bool "ARM CCN driver support"
> 
> ...meaning that it currently is not being built as a module by anyone.
> Lets remove the modular code that is essentially orphaned, so that
> when reading the driver there is no doubt it is builtin-only.
> 
> We explicitly disallow a driver unbind, since that doesn't have a
> sensible use case anyway, and it allows us to drop the ".remove"
> code for non-modular drivers.
> 
> Since module_init translates to device_initcall in the non-modular
> case, the init ordering remains unchanged with this commit.
> 
> We exchange module.h for moduleparam.h here since the driver uses
> module_param_named, and for now the easiest way to remain compatible
> with existing bootargs use cases is to leave this as-is.
> 
> We also delete the MODULE_LICENSE tag etc. since all that information
> was (or is now) contained at the top of the file in the comments.

I'd much rather fix the driver to build as a module, if at all possible.
Suzuki (CC'd) is taking a look at that, so please drop this patch for
now.

Will
Pawel Moll March 29, 2016, 11:53 a.m. UTC | #2
Dnia 2016-03-29, Tue o godzinie 12:45 +0100, Will Deacon pisze:
> I'd much rather fix the driver to build as a module, if at all
> possible.
> Suzuki (CC'd) is taking a look at that, so please drop this patch for
> now.

There's no problem with building arm-ccn.c as a module - all it's
really doing today is providing a PMU driver. I don't even know why
have I made it bool-only in the first place...

Pawel
Will Deacon March 29, 2016, 12:30 p.m. UTC | #3
On Tue, Mar 29, 2016 at 12:53:06PM +0100, Pawel Moll wrote:
> Dnia 2016-03-29, Tue o godzinie 12:45 +0100, Will Deacon pisze:
> > I'd much rather fix the driver to build as a module, if at all
> > possible.
> > Suzuki (CC'd) is taking a look at that, so please drop this patch for
> > now.
> 
> There's no problem with building arm-ccn.c as a module - all it's
> really doing today is providing a PMU driver. I don't even know why
> have I made it bool-only in the first place...

Probably because it doesn't compile due to the irq_set_affinity call.

Will
Pawel Moll March 29, 2016, 1:11 p.m. UTC | #4
On Tue, 2016-03-29 at 13:30 +0100, Will Deacon wrote:
> On Tue, Mar 29, 2016 at 12:53:06PM +0100, Pawel Moll wrote:
> > Dnia 2016-03-29, Tue o godzinie 12:45 +0100, Will Deacon pisze:
> > > I'd much rather fix the driver to build as a module, if at all
> > > possible.
> > > Suzuki (CC'd) is taking a look at that, so please drop this patch
> > > for
> > > now.
> > 
> > There's no problem with building arm-ccn.c as a module - all it's
> > really doing today is providing a PMU driver. I don't even know why
> > have I made it bool-only in the first place...
> 
> Probably because it doesn't compile due to the irq_set_affinity call.

The original arm-ccn.c did not call it at all. My guess is that I
copied ARM_CCI stanza without thinking. But I'm glad Suzuki will
straighten it out :-)

Pawe?
Paul Gortmaker March 29, 2016, 1:14 p.m. UTC | #5
[Re: [PATCH 4/4] drivers/bus: make arm-ccn.c driver explicitly non-modular] On 29/03/2016 (Tue 12:53) Pawel Moll wrote:

> Dnia 2016-03-29, Tue o godzinie 12:45 +0100, Will Deacon pisze:
> > I'd much rather fix the driver to build as a module, if at all
> > possible.
> > Suzuki (CC'd) is taking a look at that, so please drop this patch for
> > now.
> 
> There's no problem with building arm-ccn.c as a module - all it's
> really doing today is providing a PMU driver. I don't even know why
> have I made it bool-only in the first place...

My guess is that like many other instances, it originally starts out as
an innocent copy and paste during early driver development -- hence the
desire to get the code and Kconfigs consistent tree wide.

Anyway, thanks guys for tackling the conversion ; I'll shelf this patch
and watch for the conversion to hit linux-next.

Paul.
--

> 
> Pawel
diff mbox

Patch

diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c
index 7082c7268845..45d2ba72ba8e 100644
--- a/drivers/bus/arm-ccn.c
+++ b/drivers/bus/arm-ccn.c
@@ -9,6 +9,8 @@ 
  * GNU General Public License for more details.
  *
  * Copyright (C) 2014 ARM Limited
+ *
+ * Author: Pawel Moll <pawel.moll@arm.com>
  */
 
 #include <linux/ctype.h>
@@ -16,7 +18,7 @@ 
 #include <linux/idr.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
-#include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/perf_event.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
@@ -1302,20 +1304,6 @@  error_cpu_notifier:
 	return err;
 }
 
-static void arm_ccn_pmu_cleanup(struct arm_ccn *ccn)
-{
-	int i;
-
-	irq_set_affinity(ccn->irq, cpu_possible_mask);
-	unregister_cpu_notifier(&ccn->dt.cpu_nb);
-	for (i = 0; i < ccn->num_xps; i++)
-		writel(0, ccn->xp[i].base + CCN_XP_DT_CONTROL);
-	writel(0, ccn->dt.base + CCN_DT_PMCR);
-	perf_pmu_unregister(&ccn->dt.pmu);
-	ida_simple_remove(&arm_ccn_pmu_ida, ccn->dt.id);
-}
-
-
 static int arm_ccn_for_each_valid_region(struct arm_ccn *ccn,
 		int (*callback)(struct arm_ccn *ccn, int region,
 		void __iomem *base, u32 type, u32 id))
@@ -1507,15 +1495,6 @@  static int arm_ccn_probe(struct platform_device *pdev)
 	return arm_ccn_pmu_init(ccn);
 }
 
-static int arm_ccn_remove(struct platform_device *pdev)
-{
-	struct arm_ccn *ccn = platform_get_drvdata(pdev);
-
-	arm_ccn_pmu_cleanup(ccn);
-
-	return 0;
-}
-
 static const struct of_device_id arm_ccn_match[] = {
 	{ .compatible = "arm,ccn-504", },
 	{},
@@ -1525,9 +1504,9 @@  static struct platform_driver arm_ccn_driver = {
 	.driver = {
 		.name = "arm-ccn",
 		.of_match_table = arm_ccn_match,
+		.suppress_bind_attrs = true,
 	},
 	.probe = arm_ccn_probe,
-	.remove = arm_ccn_remove,
 };
 
 static int __init arm_ccn_init(void)
@@ -1539,14 +1518,4 @@  static int __init arm_ccn_init(void)
 
 	return platform_driver_register(&arm_ccn_driver);
 }
-
-static void __exit arm_ccn_exit(void)
-{
-	platform_driver_unregister(&arm_ccn_driver);
-}
-
-module_init(arm_ccn_init);
-module_exit(arm_ccn_exit);
-
-MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
-MODULE_LICENSE("GPL");
+device_initcall(arm_ccn_init);