From 92224e751f97847195b8e90a033b3e7b30ff0bd3 Mon Sep 17 00:00:00 2001
From: Karol Herbst <nouveau@karolherbst.de>
Date: Mon, 28 Mar 2016 14:24:30 +0200
Subject: [PATCH] drm/nouveau/iccsense: convert to linked list

v2: add list_del calls

Signed-off-by: Karol Herbst <nouveau@karolherbst.de>
Reviewed-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
---
 .../nouveau/include/nvkm/subdev/iccsense.h    |  4 +--
 drivers/gpu/drm/nouveau/nouveau_hwmon.c       |  2 +-
 .../drm/nouveau/nvkm/subdev/iccsense/base.c   | 34 +++++++++----------
 .../drm/nouveau/nvkm/subdev/iccsense/priv.h   |  1 +
 4 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/iccsense.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/iccsense.h
index c3defcd34d51..a4c0da0c6d72 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/iccsense.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/iccsense.h
@@ -3,12 +3,10 @@
 
 #include <core/subdev.h>
 
-struct nkvm_iccsense_rail;
 struct nvkm_iccsense {
 	struct nvkm_subdev subdev;
-	u8 rail_count;
 	bool data_valid;
-	struct nvkm_iccsense_rail *rails;
+	struct list_head rails;
 };
 
 int gf100_iccsense_new(struct nvkm_device *, int index, struct nvkm_iccsense **);
diff --git a/drivers/gpu/drm/nouveau/nouveau_hwmon.c b/drivers/gpu/drm/nouveau/nouveau_hwmon.c
index 7ecb5d910d1c..1ff4166af26e 100644
--- a/drivers/gpu/drm/nouveau/nouveau_hwmon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_hwmon.c
@@ -689,7 +689,7 @@ nouveau_hwmon_init(struct drm_device *dev)
 			goto error;
 	}
 
-	if (iccsense && iccsense->data_valid && iccsense->rail_count) {
+	if (iccsense && iccsense->data_valid && !list_empty(&iccsense->rails)) {
 		ret = sysfs_create_group(&hwmon_dev->kobj,
 					 &hwmon_power_attrgroup);
 		if (ret)
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c
index bf1b94ec6ed4..f2a210ad0cab 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/base.c
@@ -98,25 +98,21 @@ nvkm_iccsense_ina3221_read(struct nvkm_iccsense *iccsense,
 int
 nvkm_iccsense_read_all(struct nvkm_iccsense *iccsense)
 {
-	int result = 0, i;
+	int result = 0;
+	struct nvkm_iccsense_rail *rail;
 
 	if (!iccsense)
 		return -EINVAL;
 
-	if (iccsense->rail_count == 0)
-		return -ENODEV;
-
-	for (i = 0; i < iccsense->rail_count; ++i) {
+	list_for_each_entry(rail, &iccsense->rails, head) {
 		int res;
-		struct nvkm_iccsense_rail *rail = &iccsense->rails[i];
 		if (!rail->read)
 			return -ENODEV;
 
 		res = rail->read(iccsense, rail);
-		if (res >= 0)
-			result += res;
-		else
+		if (res < 0)
 			return res;
+		result += res;
 	}
 	return result;
 }
@@ -125,9 +121,12 @@ static void *
 nvkm_iccsense_dtor(struct nvkm_subdev *subdev)
 {
 	struct nvkm_iccsense *iccsense = nvkm_iccsense(subdev);
+	struct nvkm_iccsense_rail *rail, *tmp;
 
-	if (iccsense->rails)
-		kfree(iccsense->rails);
+	list_for_each_entry_safe(rail, tmp, &iccsense->rails, head) {
+		list_del(&rail->head);
+		kfree(rail);
+	}
 
 	return iccsense;
 }
@@ -145,11 +144,6 @@ nvkm_iccsense_oneinit(struct nvkm_subdev *subdev)
 	    || !stbl.nr_entry)
 		return 0;
 
-	iccsense->rails = kmalloc(sizeof(*iccsense->rails) * stbl.nr_entry,
-	                          GFP_KERNEL);
-	if (!iccsense->rails)
-		return -ENOMEM;
-
 	iccsense->data_valid = true;
 	for (i = 0; i < stbl.nr_entry; ++i) {
 		struct pwr_rail_t *r = &stbl.rail[i];
@@ -184,7 +178,10 @@ nvkm_iccsense_oneinit(struct nvkm_subdev *subdev)
 			continue;
 		}
 
-		rail = &iccsense->rails[iccsense->rail_count];
+		rail = kmalloc(sizeof(*rail), GFP_KERNEL);
+		if (!rail)
+			return -ENOMEM;
+
 		switch (extdev.type) {
 		case NVBIOS_EXTDEV_INA209:
 			rail->read = nvkm_iccsense_ina209_read;
@@ -201,7 +198,7 @@ nvkm_iccsense_oneinit(struct nvkm_subdev *subdev)
 		rail->rail = r->rail;
 		rail->mohm = r->resistor_mohm;
 		rail->i2c = &i2c_bus->i2c;
-		++iccsense->rail_count;
+		list_add_tail(&rail->head, &iccsense->rails);
 	}
 	return 0;
 }
@@ -224,6 +221,7 @@ nvkm_iccsense_new_(struct nvkm_device *device, int index,
 {
 	if (!(*iccsense = kzalloc(sizeof(**iccsense), GFP_KERNEL)))
 		return -ENOMEM;
+	INIT_LIST_HEAD(&(*iccsense)->rails);
 	nvkm_iccsense_ctor(device, index, *iccsense);
 	return 0;
 }
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/priv.h b/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/priv.h
index ed398b81e86e..e479128f0459 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/priv.h
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/iccsense/priv.h
@@ -4,6 +4,7 @@
 #include <subdev/iccsense.h>
 
 struct nvkm_iccsense_rail {
+	struct list_head head;
 	int (*read)(struct nvkm_iccsense *, struct nvkm_iccsense_rail *);
 	struct i2c_adapter *i2c;
 	u8 addr;
-- 
2.20.1