video: tegra: host: Iterate devices without nb_channels

Do not use nb_channels to find out the number of client devices.
Instead, allocate devno regions when they are needed and find a
device by module id by iterating over nvhost bus.

Bug 871237

Change-Id: I53fd0d8e5874422ef9877430c0a170db2660118a
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/99067
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>

5 files changed, 21 insertions, 28 deletions

diff --git a/drivers/video/tegra/host/bus_client.c b/drivers/video/tegra/host/bus_client.c
index a3dc3781f81c..272e0c9f2efb 100644
--- a/drivers/video/tegra/host/bus_client.c
+++ b/drivers/video/tegra/host/bus_client.c
@@ -540,18 +540,23 @@ int nvhost_client_user_init(struct nvhost_device *dev)
 	int err, devno;
 
 	struct nvhost_channel *ch = dev->channel;
+	err = alloc_chrdev_region(&devno, 0, 1, IFACE_NAME);
+	if (err < 0) {
+		dev_err(&dev->dev, "failed to allocate devno\n");
+		goto fail;
+	}
 
 	cdev_init(&ch->cdev, &nvhost_channelops);
 	ch->cdev.owner = THIS_MODULE;
 
-	devno = MKDEV(nvhost_major, nvhost_minor + dev->index);
 	err = cdev_add(&ch->cdev, devno, 1);
 	if (err < 0) {
 		dev_err(&dev->dev,
 			"failed to add chan %i cdev\n", dev->index);
 		goto fail;
 	}
-	ch->node = device_create(nvhost_get_host(dev)->nvhost_class, NULL, devno, NULL,
+	ch->node = device_create(nvhost_get_host(dev)->nvhost_class,
+			NULL, devno, NULL,
 			IFACE_NAME "-%s", dev->name);
 	if (IS_ERR(ch->node)) {
 		err = PTR_ERR(ch->node);
diff --git a/drivers/video/tegra/host/dev.c b/drivers/video/tegra/host/dev.c
index d21719bcda56..7917e4e20b44 100644
--- a/drivers/video/tegra/host/dev.c
+++ b/drivers/video/tegra/host/dev.c
@@ -51,9 +51,6 @@
 
 #define DRIVER_NAME		"host1x"
 
-int nvhost_major;
-int nvhost_minor;
-
 static unsigned int register_sets;
 
 struct nvhost_ctrl_userctx {
@@ -170,24 +167,21 @@ static int nvhost_ioctl_ctrl_module_mutex(struct nvhost_ctrl_userctx *ctx,
 	return err;
 }
 
-static struct nvhost_device *get_ndev_by_moduleid(struct nvhost_master *host,
-		u32 id)
+static int match_by_moduleid(struct device *dev, void *data)
 {
-	int i;
+	struct nvhost_device *ndev = to_nvhost_device(dev);
+	u32 id = (u32)data;
 
-	for (i = 0; i < host->nb_channels; i++) {
-		struct nvhost_device *ndev = host->channels[i].dev;
+	return id == ndev->moduleid;
+}
 
-		/* display and dsi do not use channel for register programming.
-		 * so their channels do not have device instance.
-		 * hence skip such channels from here. */
-		if (ndev == NULL)
-			continue;
+static struct nvhost_device *get_ndev_by_moduleid(struct nvhost_master *host,
+		u32 id)
+{
+	struct device *dev = bus_find_device(&nvhost_bus_type, NULL, (void *)id,
+			match_by_moduleid);
 
-		if (id == ndev->moduleid)
-			return ndev;
-	}
-	return NULL;
+	return dev ? to_nvhost_device(dev) : NULL;
 }
 
 static int nvhost_ioctl_ctrl_module_regrdwr(struct nvhost_ctrl_userctx *ctx,
@@ -332,9 +326,7 @@ static int __devinit nvhost_user_init(struct nvhost_master *host)
 		goto fail;
 	}
 
-	err = alloc_chrdev_region(&devno, nvhost_minor,
-				host->nb_channels + 1, IFACE_NAME);
-	nvhost_major = MAJOR(devno);
+	err = alloc_chrdev_region(&devno, 0, 1, IFACE_NAME);
 	if (err < 0) {
 		dev_err(&host->dev->dev, "failed to reserve chrdev region\n");
 		goto fail;
@@ -342,7 +334,6 @@ static int __devinit nvhost_user_init(struct nvhost_master *host)
 
 	cdev_init(&host->cdev, &nvhost_ctrlops);
 	host->cdev.owner = THIS_MODULE;
-	devno = MKDEV(nvhost_major, nvhost_minor + host->nb_channels);
 	err = cdev_add(&host->cdev, devno, 1);
 	if (err < 0)
 		goto fail;
diff --git a/drivers/video/tegra/host/dev.h b/drivers/video/tegra/host/dev.h
index 70199d8a5914..b357ef9f29c9 100644
--- a/drivers/video/tegra/host/dev.h
+++ b/drivers/video/tegra/host/dev.h
@@ -29,9 +29,6 @@
 #define TRACE_MAX_LENGTH	128U
 #define IFACE_NAME		"nvhost"
 
-extern int nvhost_major;
-extern int nvhost_minor;
-
 struct nvhost_hwctx;
 struct nvhost_channel;
 
diff --git a/drivers/video/tegra/host/t20/t20.c b/drivers/video/tegra/host/t20/t20.c
index 19967cb8c7a4..3f90e6a837c9 100644
--- a/drivers/video/tegra/host/t20/t20.c
+++ b/drivers/video/tegra/host/t20/t20.c
@@ -202,7 +202,7 @@ struct nvhost_device *t20_get_nvhost_device(struct nvhost_master *host,
 {
 	int i;
 
-	for (i = 0; i < host->nb_channels; i++) {
+	for (i = 0; i < ARRAY_SIZE(t20_devices); i++) {
 		if (strcmp(t20_devices[i].name, name) == 0)
 			return &t20_devices[i];
 	}
diff --git a/drivers/video/tegra/host/t30/t30.c b/drivers/video/tegra/host/t30/t30.c
index fce8081df332..01009a708d19 100644
--- a/drivers/video/tegra/host/t30/t30.c
+++ b/drivers/video/tegra/host/t30/t30.c
@@ -221,7 +221,7 @@ struct nvhost_device *t30_get_nvhost_device(struct nvhost_master *host,
 {
 	int i;
 
-	for (i = 0; i < host->nb_channels; i++) {
+	for (i = 0; i < ARRAY_SIZE(t30_devices); i++) {
 		if (strcmp(t30_devices[i].name, name) == 0)
 			return &t30_devices[i];
 	}