[PATCH] olpc_battery: bind to device tree

[Daniel Drake <dsd@laptop.org>]

Move from being statically probed by platform presence to binding to
the battery node of the device tree.

This is cleaner and allows suspend/resume (wakeup) support to be added
in a later patch.

Signed-off-by: Daniel Drake <dsd@laptop.org>
---
 arch/x86/platform/olpc/olpc_dt.c |   13 +++++++
 drivers/power/Kconfig            |    2 +-
 drivers/power/olpc_battery.c     |   66 +++++++++++++++++++++++++------------
 3 files changed, 58 insertions(+), 23 deletions(-)

Replaces patch "olpc_battery: convert to platform device"

The problem mentioned in another mail regarding devicetree binding is now
fixed via separate patches from Andres.

diff --git a/arch/x86/platform/olpc/olpc_dt.c b/arch/x86/platform/olpc/olpc_dt.c
index dab8746..97211c1 100644
--- a/arch/x86/platform/olpc/olpc_dt.c
+++ b/arch/x86/platform/olpc/olpc_dt.c
@@ -19,6 +19,7 @@
 #include <linux/kernel.h>
 #include <linux/bootmem.h>
 #include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/of_pdt.h>
 #include <asm/olpc_ofw.h>
 
@@ -181,3 +182,15 @@ void __init olpc_dt_build_devicetree(void)
 	pr_info("PROM DT: Built device tree with %u bytes of memory.\n",
 			prom_early_allocated);
 }
+
+/* A list of DT node/bus matches that we want to expose as platform devices */
+static struct of_device_id __initdata of_ids[] = {
+	{ .name = "battery" },
+	{},
+};
+
+static int __init declare_of_platform_devices(void)
+{
+	return of_platform_bus_probe(NULL, of_ids, NULL);
+}
+device_initcall(declare_of_platform_devices);
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 61bf5d7..3a9151d 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -84,7 +84,7 @@ config BATTERY_PMU
 
 config BATTERY_OLPC
 	tristate "One Laptop Per Child battery"
-	depends on X86_32 && OLPC
+	depends on X86_32 && OLPC && OF
 	help
 	  Say Y to enable support for the battery on the OLPC laptop.
 
diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
index 0b0ff3a..99fc8e0 100644
--- a/drivers/power/olpc_battery.c
+++ b/drivers/power/olpc_battery.c
@@ -17,6 +17,7 @@
 #include <linux/power_supply.h>
 #include <linux/jiffies.h>
 #include <linux/sched.h>
+#include <linux/of_platform.h>
 #include <asm/olpc.h>
 
 
@@ -519,9 +520,8 @@ static struct device_attribute olpc_bat_error = {
  *		Initialisation
  *********************************************************************/
 
-static struct platform_device *bat_pdev;
-
 static struct power_supply olpc_bat = {
+	.name = "olpc-battery",
 	.get_property = olpc_bat_get_property,
 	.use_for_apm = 1,
 };
@@ -534,13 +534,18 @@ 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,
+					const struct of_device_id *match)
 {
-	int ret = 0;
+	int ret;
 	uint8_t status;
+	struct device_node *root;
+	const char *arch;
+	int propsize;
 
-	if (!olpc_platform_info.ecver)
-		return -ENXIO;
+	/* Check that we're running on an XO laptop */
+	if (!machine_is_olpc())
+		return -ENODEV;
 
 	/*
 	 * We've seen a number of EC protocol changes; this driver requires
@@ -552,21 +557,15 @@ 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;
 	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 +574,7 @@ 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 +586,7 @@ 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 +594,42 @@ 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 const struct of_device_id olpc_battery_ids[] __devinitconst = {
+	{ .name = "battery" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, olpc_battery_ids);
+
+static struct of_platform_driver olpc_battery_drv = {
+	.driver = {
+		.name = "olpc-battery",
+		.owner = THIS_MODULE,
+		.of_match_table = olpc_battery_ids,
+	},
+	.probe = olpc_battery_probe,
+	.remove = __devexit_p(olpc_battery_remove),
+};
+
+static int __init olpc_bat_init(void)
+{
+	return of_register_platform_driver(&olpc_battery_drv);
+}
+
+static void __exit olpc_bat_exit(void)
+{
+	of_unregister_platform_driver(&olpc_battery_drv);
 }
 
 module_init(olpc_bat_init);
-- 
1.7.4