[alsa-devel] [PATCH v2 1/7 v2] ARM: OMAP1: ams-delta: register latch dependent devices later

Janusz Krzysztofik jkrzyszt at tis.icnet.pl
Tue Dec 20 22:54:18 CET 2011

In preparation to converting Amstrad Delta on-board latches to
basic_mmio_gpio devices, registration of platform devices which depend
on latches and will require initialization of their GPIO pins first,
should be moved out of .machine_init down to late_initcall level, as the
gpio-generic driver is not available until device_initcall time.  The
latch reset operation, which will be replaced with GPIO initialization,
must also be moved to late_initcall for the same reason.

Since there was already another, separate arch_initcall function for
setting up one of those latch dependent devices, the on-board modem
device, reuse that function, i.e., rename it to a name that matches the
new purpose, extend with other device setup relocated from
.machine_init, and move down to the late_initcall level.

While being at it, add missing gpio_free() in case the modem platform
device registration fails.

Thanks to Tony Lindgren <tony at atomide.com> who suggested this approach
instead of shifting up the gpio-generic driver initialization.

In addition, defer registration of the Amstrad Delta ASoC and serio
devices, done from their device driver files, until late_initcall time,
as those drivers will depend on their GPIO pins already requested from
the board late_init() function until updated to register their GPIO pins

Created and tested against linux-3.2-rc6.

Signed-off-by: Janusz Krzysztofik <jkrzyszt at tis.icnet.pl>
Changes since the initial version of this patch:
* use late_initcall() unconditionally in modules, requested by Russell
  King (thanks!); an updated patch 7/7 will follow,
* in the changelog message, move credits to Tony up a bit, since the
  person responsible for other changes (he might not necessarily like)
  is me, not him ;).

Comments copied from this patch initial submission:
This patch was not present in the initial submission, it replaces the
old patch 1/10, providing an alternative solution not touching the
gpio-generic driver.

 arch/arm/mach-omap1/board-ams-delta.c |   28 ++++++++++++++++++++--------
 drivers/input/serio/ams_delta_serio.c |    2 +-
 sound/soc/omap/ams-delta.c            |    2 +-
 3 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c
index b0f15d2..50987c9 100644
--- a/arch/arm/mach-omap1/board-ams-delta.c
+++ b/arch/arm/mach-omap1/board-ams-delta.c
@@ -275,11 +275,14 @@ static struct omap1_cam_platform_data ams_delta_camera_platform_data = {
 static struct platform_device *ams_delta_devices[] __initdata = {
-	&ams_delta_nand_device,
+	&ams_delta_camera_device,
+static struct platform_device *late_devices[] __initdata = {
+	&ams_delta_nand_device,
-	&ams_delta_camera_device,
 static void __init ams_delta_init(void)
@@ -307,9 +310,6 @@ static void __init ams_delta_init(void)
 	omap_register_i2c_bus(1, 100, NULL, 0);
-	/* Clear latch2 (NAND, LCD, modem enable) */
-	ams_delta_latch2_write(~0, 0);
@@ -345,13 +345,18 @@ static struct platform_device ams_delta_modem_device = {
-static int __init ams_delta_modem_init(void)
+static int __init late_init(void)
 	int err;
 	if (!machine_is_ams_delta())
 		return -ENODEV;
+	/* Clear latch2 (NAND, LCD, modem enable) */
+	ams_delta_latch2_write(~0, 0);
+	platform_add_devices(late_devices, ARRAY_SIZE(late_devices));
 	ams_delta_modem_ports[0].irq =
@@ -367,9 +372,16 @@ static int __init ams_delta_modem_init(void)
-	return platform_device_register(&ams_delta_modem_device);
+	err = platform_device_register(&ams_delta_modem_device);
+	if (err)
+		goto gpio_free;
+	return 0;
+	return err;
 static void __init ams_delta_map_io(void)
diff --git a/drivers/input/serio/ams_delta_serio.c b/drivers/input/serio/ams_delta_serio.c
index d4d08bd..835d37a 100644
--- a/drivers/input/serio/ams_delta_serio.c
+++ b/drivers/input/serio/ams_delta_serio.c
@@ -165,7 +165,7 @@ serio:
 	return err;
 static void __exit ams_delta_serio_exit(void)
diff --git a/sound/soc/omap/ams-delta.c b/sound/soc/omap/ams-delta.c
index ccb8a6a..be81bc7 100644
--- a/sound/soc/omap/ams-delta.c
+++ b/sound/soc/omap/ams-delta.c
@@ -636,7 +636,7 @@ err:
 	return ret;
 static void __exit ams_delta_module_exit(void)

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