Hello Li, On Fri Sep 4, 2026 at 3:49 AM CEST, Li Youhong wrote: > From: Li Youhong <[email protected]> > > When the Exynos DSI driver was generalized into samsung-dsim, the TE > GPIO acquisition was switched from gpiod_get_optional() to > devm_gpiod_get_optional() while keeping the matching gpiod_put() calls. > That combination is wrong for a managed descriptor. > > However, dropping the puts and keeping the managed get is also wrong: > samsung_dsim_register_te_irq() runs from the DSI host attach callback, > and host detach/reattach can happen without destroying the device that > owns the managed action. A second attach would then request the GPIO > again without having released it. > > Switch back to a non-managed gpiod_get_optional() and keep the explicit > gpiod_put() on the request_irq() error path and in > samsung_dsim_unregister_te_irq(). > > Fixes: e7447128ca4a ("drm: bridge: Generalize Exynos-DSI driver into a > Samsung DSIM bridge") > Suggested-by: Luca Ceresoli <[email protected]> > Signed-off-by: Li Youhong <[email protected]> > --- > v2: > - Prefer non-devm gpiod_get_optional() and keep gpiod_put(), because TE > GPIO is acquired in host attach and must be released on host detach > > drivers/gpu/drm/bridge/samsung-dsim.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > --- a/drivers/gpu/drm/bridge/samsung-dsim.c > +++ b/drivers/gpu/drm/bridge/samsung-dsim.c > @@ -1862,7 +1862,8 @@ static int samsung_dsim_register_te_irq(struct > samsung_dsim *dsi, struct device > int te_gpio_irq; > int ret; > > - dsi->te_gpio = devm_gpiod_get_optional(dev, "te", GPIOD_IN); > + /* Released on host detach; do not use the managed get. */ > + dsi->te_gpio = gpiod_get_optional(dev, "te", GPIOD_IN);
The comment is not really needed, this should be obvious by reading the code. No need to resend just for that, I can remove it while applying. Other than that it's OK: Reviewed-by: Luca Ceresoli <[email protected]> Tested-by: Luca Ceresoli <[email protected]> Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
