[PATCH v4 1/2] nouveau/bl: Assign different names to interfaces
Pierre Moreau
pierre.morrow at free.fr
Wed Dec 7 23:57:08 UTC 2016
Currently, every backlight interface created by Nouveau uses the same name,
nv_backlight. This leads to a sysfs warning as it tries to create an already
existing folder. This patch adds a incremented number to the name, but keeps
the initial name as nv_backlight, to avoid possibly breaking userspace; the
second interface will be named nv_backlight1, and so on.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86539
v2:
* Switch to using ida for generating unique IDs, as suggested by Ilia Mirkin;
* Allocate backlight name on the stack, as suggested by Ilia Mirkin;
* Move `nouveau_get_backlight_name()` to avoid forward declaration, as
suggested by Ilia Mirkin;
* Fix reference to bug report formatting, as reported by Nick Tenney.
v3:
* Define a macro for the size of the backlight name, to avoid defining
it multiple times;
* Use snprintf in place of sprintf.
v4:
* Do not create similarly named interfaces when reaching the maximum
amount of unique names, but fail instead, as pointed out by Lukas Wunner
Signed-off-by: Pierre Moreau <pierre.morrow at free.fr>
---
drm/nouveau/nouveau_backlight.c | 74 ++++++++++++++++++++++++++++++++++++++---
drm/nouveau/nouveau_display.h | 10 ++++++
drm/nouveau/nouveau_drm.c | 2 ++
drm/nouveau/nouveau_drv.h | 1 +
4 files changed, 83 insertions(+), 4 deletions(-)
diff --git a/drm/nouveau/nouveau_backlight.c b/drm/nouveau/nouveau_backlight.c
index 5e2c568..a34cd35 100644
--- a/drm/nouveau/nouveau_backlight.c
+++ b/drm/nouveau/nouveau_backlight.c
@@ -31,11 +31,35 @@
*/
#include <linux/backlight.h>
+#include <linux/idr.h>
#include "nouveau_drv.h"
#include "nouveau_reg.h"
#include "nouveau_encoder.h"
+static struct ida bl_ida;
+#define BL_NAME_SIZE 15 // 12 for name + 2 for digits + 1 for '\0'
+
+struct backlight_connector {
+ struct list_head head;
+ int id;
+};
+
+static bool
+nouveau_get_backlight_name(char backlight_name[BL_NAME_SIZE], struct backlight_connector
+ *connector)
+{
+ const int nb = ida_simple_get(&bl_ida, 0, 0, GFP_KERNEL);
+ if (nb < 0 || nb >= 100)
+ return false;
+ if (nb > 0)
+ snprintf(backlight_name, BL_NAME_SIZE, "nv_backlight%d", nb);
+ else
+ snprintf(backlight_name, BL_NAME_SIZE, "nv_backlight");
+ connector->id = nb;
+ return true;
+}
+
static int
nv40_get_intensity(struct backlight_device *bd)
{
@@ -74,6 +98,8 @@ nv40_backlight_init(struct drm_connector *connector)
struct nvif_object *device = &drm->device.object;
struct backlight_properties props;
struct backlight_device *bd;
+ struct backlight_connector bl_connector;
+ char backlight_name[BL_NAME_SIZE];
if (!(nvif_rd32(device, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK))
return 0;
@@ -81,10 +107,19 @@ nv40_backlight_init(struct drm_connector *connector)
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = 31;
- bd = backlight_device_register("nv_backlight", connector->kdev, drm,
+ if (!nouveau_get_backlight_name(backlight_name, &bl_connector)) {
+ NV_ERROR(drm, "Failed to retrieve a unique name for the backlight interface\n");
+ return 0;
+ }
+ bd = backlight_device_register(backlight_name , connector->kdev, drm,
&nv40_bl_ops, &props);
- if (IS_ERR(bd))
+
+ if (IS_ERR(bd)) {
+ if (bl_connector.id > 0)
+ ida_simple_remove(&bl_ida, bl_connector.id);
return PTR_ERR(bd);
+ }
+ list_add(&bl_connector.head, &drm->bl_connectors);
drm->backlight = bd;
bd->props.brightness = nv40_get_intensity(bd);
backlight_update_status(bd);
@@ -182,6 +217,8 @@ nv50_backlight_init(struct drm_connector *connector)
struct backlight_properties props;
struct backlight_device *bd;
const struct backlight_ops *ops;
+ struct backlight_connector bl_connector;
+ char backlight_name[BL_NAME_SIZE];
nv_encoder = find_encoder(connector, DCB_OUTPUT_LVDS);
if (!nv_encoder) {
@@ -203,11 +240,20 @@ nv50_backlight_init(struct drm_connector *connector)
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = 100;
- bd = backlight_device_register("nv_backlight", connector->kdev,
+ if (!nouveau_get_backlight_name(backlight_name, &bl_connector)) {
+ NV_ERROR(drm, "Failed to retrieve a unique name for the backlight interface\n");
+ return 0;
+ }
+ bd = backlight_device_register(backlight_name , connector->kdev,
nv_encoder, ops, &props);
- if (IS_ERR(bd))
+
+ if (IS_ERR(bd)) {
+ if (bl_connector.id > 0)
+ ida_simple_remove(&bl_ida, bl_connector.id);
return PTR_ERR(bd);
+ }
+ list_add(&bl_connector.head, &drm->bl_connectors);
drm->backlight = bd;
bd->props.brightness = bd->ops->get_brightness(bd);
backlight_update_status(bd);
@@ -221,6 +267,8 @@ nouveau_backlight_init(struct drm_device *dev)
struct nvif_device *device = &drm->device;
struct drm_connector *connector;
+ INIT_LIST_HEAD(&drm->bl_connectors);
+
list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
if (connector->connector_type != DRM_MODE_CONNECTOR_LVDS &&
connector->connector_type != DRM_MODE_CONNECTOR_eDP)
@@ -247,9 +295,27 @@ void
nouveau_backlight_exit(struct drm_device *dev)
{
struct nouveau_drm *drm = nouveau_drm(dev);
+ struct backlight_connector *connector;
+
+ list_for_each_entry(connector, &drm->bl_connectors, head) {
+ if (connector->id >= 0)
+ ida_simple_remove(&bl_ida, connector->id);
+ }
if (drm->backlight) {
backlight_device_unregister(drm->backlight);
drm->backlight = NULL;
}
}
+
+void
+nouveau_backlight_ctor(void)
+{
+ ida_init(&bl_ida);
+}
+
+void
+nouveau_backlight_dtor(void)
+{
+ ida_destroy(&bl_ida);
+}
diff --git a/drm/nouveau/nouveau_display.h b/drm/nouveau/nouveau_display.h
index 330fe0f..4a75df0 100644
--- a/drm/nouveau/nouveau_display.h
+++ b/drm/nouveau/nouveau_display.h
@@ -91,6 +91,8 @@ int nouveau_crtc_set_config(struct drm_mode_set *set);
#ifdef CONFIG_DRM_NOUVEAU_BACKLIGHT
extern int nouveau_backlight_init(struct drm_device *);
extern void nouveau_backlight_exit(struct drm_device *);
+extern void nouveau_backlight_ctor(void);
+extern void nouveau_backlight_dtor(void);
#else
static inline int
nouveau_backlight_init(struct drm_device *dev)
@@ -101,6 +103,14 @@ nouveau_backlight_init(struct drm_device *dev)
static inline void
nouveau_backlight_exit(struct drm_device *dev) {
}
+
+static inline void
+nouveau_backlight_ctor(void) {
+}
+
+static inline void
+nouveau_backlight_dtor(void) {
+}
#endif
struct drm_framebuffer *
diff --git a/drm/nouveau/nouveau_drm.c b/drm/nouveau/nouveau_drm.c
index 064a925..59348fc 100644
--- a/drm/nouveau/nouveau_drm.c
+++ b/drm/nouveau/nouveau_drm.c
@@ -1122,6 +1122,7 @@ nouveau_drm_init(void)
#endif
nouveau_register_dsm_handler();
+ nouveau_backlight_ctor();
return drm_pci_init(&driver_pci, &nouveau_drm_pci_driver);
}
@@ -1132,6 +1133,7 @@ nouveau_drm_exit(void)
return;
drm_pci_exit(&driver_pci, &nouveau_drm_pci_driver);
+ nouveau_backlight_dtor();
nouveau_unregister_dsm_handler();
#ifdef CONFIG_NOUVEAU_PLATFORM_DRIVER
diff --git a/drm/nouveau/nouveau_drv.h b/drm/nouveau/nouveau_drv.h
index 9730c0e..8d5ed5b 100644
--- a/drm/nouveau/nouveau_drv.h
+++ b/drm/nouveau/nouveau_drv.h
@@ -163,6 +163,7 @@ struct nouveau_drm {
struct nvbios vbios;
struct nouveau_display *display;
struct backlight_device *backlight;
+ struct list_head bl_connectors;
struct work_struct hpd_work;
#ifdef CONFIG_ACPI
struct notifier_block acpi_nb;
--
2.10.2
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