| Message ID | 20240827-efifb-sysfs-v1-3-c9cc3e052180@weissschuh.net (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | fbdev: devm_register_framebuffer() and some fixes for efifb | expand |
Hi everybody, On 2024-08-27 17:25:14+0000, Thomas Weißschuh wrote: > Introduce a device-managed variant of register_framebuffer() which > automatically unregisters the framebuffer on device destruction. > This can simplify the error handling and resource management in drivers. Bert reported that this series broke his framebuffer ([0], [1]). [0] https://lore.kernel.org/lkml/20240829224124.2978-1-spasswolf@web.de/ [1] https://lore.kernel.org/lkml/20240829230438.3226-1-spasswolf@web.de/ > Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> > --- > drivers/video/fbdev/core/fbmem.c | 24 ++++++++++++++++++++++++ > include/linux/fb.h | 1 + > 2 files changed, 25 insertions(+) > > diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c > index 4c4ad0a86a50..d17a2daa2483 100644 > --- a/drivers/video/fbdev/core/fbmem.c > +++ b/drivers/video/fbdev/core/fbmem.c > @@ -544,6 +544,30 @@ unregister_framebuffer(struct fb_info *fb_info) [..] > +/** > + * devm_register_framebuffer - resource-managed frame buffer device registration > + * @dev: device the framebuffer belongs to > + * @fb_info: frame buffer info structure > + * > + * Registers a frame buffer device @fb_info to device @dev. > + * > + * Returns negative errno on error, or zero for success. > + * > + */ > +int > +devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) > +{ > + return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); > +} > +EXPORT_SYMBOL(devm_register_framebuffer); This implementation is wrong, it never actually registers the framebuffer. It should look like this: int devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) { int ret; ret = register_framebuffer(fb_info); if (ret) return ret; return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); } EXPORT_SYMBOL(devm_register_framebuffer); Bert, could you test this? Helge, do you want me to resend the series, minus the original patch 1?
Am Freitag, dem 30.08.2024 um 09:17 +0200 schrieb Thomas Weißschuh: > Hi everybody, > > On 2024-08-27 17:25:14+0000, Thomas Weißschuh wrote: > > Introduce a device-managed variant of register_framebuffer() which > > automatically unregisters the framebuffer on device destruction. > > This can simplify the error handling and resource management in drivers. > > Bert reported that this series broke his framebuffer ([0], [1]). > > [0] https://lore.kernel.org/lkml/20240829224124.2978-1-spasswolf@web.de/ > [1] https://lore.kernel.org/lkml/20240829230438.3226-1-spasswolf@web.de/ > > > Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> > > --- > > drivers/video/fbdev/core/fbmem.c | 24 ++++++++++++++++++++++++ > > include/linux/fb.h | 1 + > > 2 files changed, 25 insertions(+) > > > > diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c > > index 4c4ad0a86a50..d17a2daa2483 100644 > > --- a/drivers/video/fbdev/core/fbmem.c > > +++ b/drivers/video/fbdev/core/fbmem.c > > @@ -544,6 +544,30 @@ unregister_framebuffer(struct fb_info *fb_info) > > [..] > > > +/** > > + * devm_register_framebuffer - resource-managed frame buffer device registration > > + * @dev: device the framebuffer belongs to > > + * @fb_info: frame buffer info structure > > + * > > + * Registers a frame buffer device @fb_info to device @dev. > > + * > > + * Returns negative errno on error, or zero for success. > > + * > > + */ > > +int > > +devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) > > +{ > > + return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); > > +} > > +EXPORT_SYMBOL(devm_register_framebuffer); > > This implementation is wrong, it never actually registers the > framebuffer. It should look like this: > > int > devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) > { > int ret; > > ret = register_framebuffer(fb_info); > if (ret) > return ret; > > return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); > } > EXPORT_SYMBOL(devm_register_framebuffer); > > Bert, could you test this? > Helge, do you want me to resend the series, minus the original patch 1? Yes, this works for me. Thanks! Bert Karwatzki
On 8/30/24 10:25, Bert Karwatzki wrote: > Am Freitag, dem 30.08.2024 um 09:17 +0200 schrieb Thomas Weißschuh: >> Hi everybody, >> >> On 2024-08-27 17:25:14+0000, Thomas Weißschuh wrote: >>> Introduce a device-managed variant of register_framebuffer() which >>> automatically unregisters the framebuffer on device destruction. >>> This can simplify the error handling and resource management in drivers. >> >> Bert reported that this series broke his framebuffer ([0], [1]). >> >> [0] https://lore.kernel.org/lkml/20240829224124.2978-1-spasswolf@web.de/ >> [1] https://lore.kernel.org/lkml/20240829230438.3226-1-spasswolf@web.de/ >> >>> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> >>> --- >>> drivers/video/fbdev/core/fbmem.c | 24 ++++++++++++++++++++++++ >>> include/linux/fb.h | 1 + >>> 2 files changed, 25 insertions(+) >>> >>> diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c >>> index 4c4ad0a86a50..d17a2daa2483 100644 >>> --- a/drivers/video/fbdev/core/fbmem.c >>> +++ b/drivers/video/fbdev/core/fbmem.c >>> @@ -544,6 +544,30 @@ unregister_framebuffer(struct fb_info *fb_info) >> >> [..] >> >>> +/** >>> + * devm_register_framebuffer - resource-managed frame buffer device registration >>> + * @dev: device the framebuffer belongs to >>> + * @fb_info: frame buffer info structure >>> + * >>> + * Registers a frame buffer device @fb_info to device @dev. >>> + * >>> + * Returns negative errno on error, or zero for success. >>> + * >>> + */ >>> +int >>> +devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) >>> +{ >>> + return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); >>> +} >>> +EXPORT_SYMBOL(devm_register_framebuffer); >> >> This implementation is wrong, it never actually registers the >> framebuffer. It should look like this: >> >> int >> devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) >> { >> int ret; >> >> ret = register_framebuffer(fb_info); >> if (ret) >> return ret; >> >> return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); >> } >> EXPORT_SYMBOL(devm_register_framebuffer); >> >> Bert, could you test this? >> Helge, do you want me to resend the series, minus the original patch 1? > > Yes, this works for me. Thanks! Good. Thomas, please just resend the fixed patch #3 (this one). And maybe you want to document devm_unregister_framebuffer() similiar to what you added for devm_register_framebuffer() ? Helge
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 4c4ad0a86a50..d17a2daa2483 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -544,6 +544,30 @@ unregister_framebuffer(struct fb_info *fb_info) } EXPORT_SYMBOL(unregister_framebuffer); +static void devm_unregister_framebuffer(void *data) +{ + struct fb_info *info = data; + + unregister_framebuffer(info); +} + +/** + * devm_register_framebuffer - resource-managed frame buffer device registration + * @dev: device the framebuffer belongs to + * @fb_info: frame buffer info structure + * + * Registers a frame buffer device @fb_info to device @dev. + * + * Returns negative errno on error, or zero for success. + * + */ +int +devm_register_framebuffer(struct device *dev, struct fb_info *fb_info) +{ + return devm_add_action_or_reset(dev, devm_unregister_framebuffer, fb_info); +} +EXPORT_SYMBOL(devm_register_framebuffer); + /** * fb_set_suspend - low level driver signals suspend * @info: framebuffer affected diff --git a/include/linux/fb.h b/include/linux/fb.h index db7d97b10964..abf6643ebcaf 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -601,6 +601,7 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf, /* fbmem.c */ extern int register_framebuffer(struct fb_info *fb_info); extern void unregister_framebuffer(struct fb_info *fb_info); +extern int devm_register_framebuffer(struct device *dev, struct fb_info *fb_info); extern char* fb_get_buffer_offset(struct fb_info *info, struct fb_pixmap *buf, u32 size); extern void fb_pad_unaligned_buffer(u8 *dst, u32 d_pitch, u8 *src, u32 idx, u32 height, u32 shift_high, u32 shift_low, u32 mod);
Introduce a device-managed variant of register_framebuffer() which automatically unregisters the framebuffer on device destruction. This can simplify the error handling and resource management in drivers. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> --- drivers/video/fbdev/core/fbmem.c | 24 ++++++++++++++++++++++++ include/linux/fb.h | 1 + 2 files changed, 25 insertions(+)