From db1a0ae21461afa4bc435651a6dd55e0e6ef4a8b Mon Sep 17 00:00:00 2001 From: Pierre Moreau Date: Thu, 8 Dec 2016 00:57:08 +0100 Subject: [PATCH] drm/nouveau/bl: Assign different names to interfaces 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 Signed-off-by: Ben Skeggs --- drivers/gpu/drm/nouveau/nouveau_backlight.c | 74 +++++++++++++++++++-- drivers/gpu/drm/nouveau/nouveau_display.h | 10 +++ drivers/gpu/drm/nouveau/nouveau_drm.c | 2 + drivers/gpu/drm/nouveau/nouveau_drv.h | 1 + 4 files changed, 83 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c index 5e2c5685b4dd..a34cd35d4965 100644 --- a/drivers/gpu/drm/nouveau/nouveau_backlight.c +++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c @@ -31,11 +31,35 @@ */ #include +#include #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/drivers/gpu/drm/nouveau/nouveau_display.h b/drivers/gpu/drm/nouveau/nouveau_display.h index 330fe0fc5c11..4a75df06c139 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.h +++ b/drivers/gpu/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/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c index 064a925ed69a..59348fc41c77 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.c +++ b/drivers/gpu/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/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h index 9730c0ef6c6a..8d5ed5bfdacb 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drv.h +++ b/drivers/gpu/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; -- 2.39.5