ARM: amba: Enable module alias autogeneration for AMBA drivers

This patch adds the necessary support in file2alias.c to define suitable aliases based on the amba_id table in AMBA driver modules.

This should be sufficient to allow such modules to be auto-loaded via udev. The AMBA bus driver's uevent hotplug code is also modified to pass an approriate MODALIAS string in the event.

For simplicity, the AMBA ID is treated an an opaque 32-bit numeber. Module alises use patterns as appropriate to describe the value- mask pairs described in the driver's amba_id list.

The proposed alias format is (extended regex):

        ^amba:d(HEX){8}$

Where HEX is a single upper-case HEX digit or a pattern (? or [] expression) matching a single upper-case HEX digit, as expected by udev.

"d" is short for "device", following existing alias naming conventions for other device types. This adds some flexibility for unambiguously extending the alias format in the future by adding additional leading and trailing fields, if this turns out to be necessary.

Signed-off-by Dave Martin <[email protected]>

Signed-off-by Dave Martin <[email protected]>

---
 drivers/dma/amba-pl08x.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

drivers/dma/amba-pl08x.c +0 -0

index b7cbd1a..0698695 100644

Signed-off-by Dave Martin <[email protected]>

---
?drivers/dma/pl330.c | ? ?2 ++
?1 files changed, 2 insertions(+), 0 deletions(-)

drivers/dma/pl330.c +2 -0

index 57104147..2d8d1b0 100644
@@ -990,6 +990,8 @@ static struct amba_id pl330_ids[] = {
 ? ? ? ?{ 0, 0 },
 ?};
 
+MODULE_DEVICE_TABLE(amba, pl330_ids);
+

?#ifdef CONFIG_PM_RUNTIME
?static int pl330_runtime_suspend(struct device *dev) ?{

Quoted 13 lines · Dave Martin

Signed-off-by Dave Martin <[email protected]>

---
 drivers/dma/pl330.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

drivers/dma/pl330.c +0 -0

index 57104147..2d8d1b0 100644
@@ -990,6 +990,8 @@ static struct amba_id pl330_ids[] = {
       { 0, 0 },
 };
 

drivers/dma/pl330.c static struct amba_id pl330_ids[] = { · line 997

Quoted 5 lines

drivers/dma/pl330.c +2 -0

+MODULE_DEVICE_TABLE(amba, pl330_ids);
+
 #ifdef CONFIG_PM_RUNTIME
 static int pl330_runtime_suspend(struct device *dev)
 {

Acked-by Jassi Brar <[email protected]>

Signed-off-by Dave Martin <[email protected]>

---
?drivers/gpio/gpio-pl061.c | ? ?2 ++
?1 files changed, 2 insertions(+), 0 deletions(-)

drivers/gpio/gpio-pl061.c +2 -1

index 2c5a18f..503e9d5 100644
@@ -339,6 +339,8 @@ static struct amba_id pl061_ids[] = {
 ? ? ? ?{ 0, 0 },
 ?};
 
+MODULE_DEVICE_TABLE(amba, pl061_ids);
+
 ?static struct amba_driver pl061_gpio_driver = {
 ? ? ? ?.drv = {
 ? ? ? ? ? ? ? ?.name ? = "pl061_gpio",
--

1.7.4.1

Signed-off-by Dave Martin <[email protected]>

---
 drivers/input/serio/ambakmi.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

drivers/input/serio/ambakmi.c +2 -0

index 12abc50..8407d5b 100644
@@ -195,6 +195,8 @@ static struct amba_id amba_kmi_idtable[] = {
 	{ 0, 0 }
 };
 
+MODULE_DEVICE_TABLE(amba, amba_kmi_idtable);
+
 static struct amba_driver ambakmi_driver = {
 	.drv		= {
 		.name	= "kmi-pl050",

Signature · 1 line

1.7.4.1

Signed-off-by Dave Martin <[email protected]>

---
?drivers/spi/spi-pl022.c | ? ?2 ++
?1 files changed, 2 insertions(+), 0 deletions(-)

drivers/spi/spi-pl022.c +2 -1

index f103e470..43abaf2 100644
@@ -2424,6 +2424,8 @@ static struct amba_id pl022_ids[] = {
 ? ? ? ?{ 0, 0 },
 ?};
 
+MODULE_DEVICE_TABLE(amba, pl022_ids);
+
 ?static struct amba_driver pl022_driver = {
 ? ? ? ?.drv = {
 ? ? ? ? ? ? ? ?.name ? = "ssp-pl022",
--

1.7.4.1

Signed-off-by Dave Martin <[email protected]>

---
?drivers/spi/spi-pl022.c | ? ?2 ++
?1 files changed, 2 insertions(+), 0 deletions(-)

There's no special reason why AMBA device drivers should not be auto-loadable via udev, but udev currently has no way to map AMBA device IDs to drivers.

As part of the effort to help enable the building of multiple ARM platforms into a single kernel image in the future, it's desirable to be able to build any non-critical platform-specific drivers as modules.

A straightforward solution is to use modaliases to allow udev to identify the correct driver module to load.

This series enables the general infrastructure for modalias generation to work for AMBA devices, and enables it in the affected drivers.

Briefly tested on Versatile Express, including aaci, mmci and amba-clcd (which appears to have the most interesting modalias match pattern). For me, the appropiate modules now get loaded at udev trigger time.

Any comments and feedback are welcome.

Dave Martin (16):
ARM: amba: Move definition of struct amba_id to mod_devicetable.h
ARM: amba: Auto-generate AMBA driver module aliases during modpost
hwrng: nomadik: Enable module alias autogeneration for AMBA drivers
dmaengine: pl08x: Enable module alias autogeneration for AMBA drivers
dmaengine: pl330: Enable module alias autogeneration for AMBA drivers
gpio: pl061: Enable module alias autogeneration for AMBA drivers
input: ambakmi: Enable module alias autogeneration for AMBA drivers
mmc: mmci: Enable module alias autogeneration for AMBA drivers
rtc: pl030: Enable module alias autogeneration for AMBA drivers
rtc: pl031: Enable module alias autogeneration for AMBA drivers
spi: pl022: Enable module alias autogeneration for AMBA drivers
serial: pl010: Enable module alias autogeneration for AMBA drivers
serial: pl011: Enable module alias autogeneration for AMBA drivers
fbdev: amba: Enable module alias autogeneration for AMBA drivers
watchdog: sp805: Enable module alias autogeneration for AMBA drivers
sound: aaci: Enable module alias autogeneration for AMBA drivers

 drivers/amba/bus.c                   |    9 ++++-
 drivers/char/hw_random/nomadik-rng.c |    2 +
 drivers/dma/amba-pl08x.c             |    2 +
 drivers/dma/pl330.c                  |    2 +
 drivers/gpio/gpio-pl061.c            |    2 +
 drivers/input/serio/ambakmi.c        |    2 +
 drivers/mmc/host/mmci.c              |    2 +
 drivers/rtc/rtc-pl030.c              |    2 +
 drivers/rtc/rtc-pl031.c              |    2 +
 drivers/spi/spi-pl022.c              |    2 +
 drivers/tty/serial/amba-pl010.c      |    2 +
 drivers/tty/serial/amba-pl011.c      |    2 +
 drivers/video/amba-clcd.c            |    2 +
 drivers/watchdog/sp805_wdt.c         |    2 +
 include/linux/amba/bus.h             |    7 +---
 include/linux/mod_devicetable.h      |   18 ++++++++
 scripts/mod/file2alias.c             |   72 ++++++++++++++++++++++++++++++++++
 sound/arm/aaci.c                     |    2 +
 18 files changed, 127 insertions(+), 7 deletions(-)

Signature · 1 line

1.7.4.1

Russell, did you have a view on this series?

Following your suggestion I was able to use the generic modpost infrastructure instead of reinventing stuff, and it seemes to work out quite neatly.

Hopefully the only possibly-contraversial change change is the movement of struct amba_id.

Quoted 6 lines · Dave Martin

Russell, did you have a view on this series?

Following your suggestion I was able to use the generic modpost infrastructure instead of reinventing stuff, and it seemes to work out quite neatly.

Quoted 2 lines

Hopefully the only possibly-contraversial change change is the movement of struct amba_id.

I think it looks fine - but I would like to see the first patch getting a wider distribution before accepting the series - I think it needs to go to at least lkml.org just in case someone has an issue with it.