5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maxime Ripard <maxime@xxxxxxxxxx> [ Upstream commit db6568498b35a4d5d5a99420df27ed25fae31406 ] MIPI-DSI devices need to call mipi_dsi_attach() when their probe is done to attach against their host. However, at removal or when an error occurs, that attachment needs to be undone through a call to mipi_dsi_detach(). Let's create a device-managed variant of the attachment function that will automatically detach the device at unbind. Reviewed-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20210910101218.1632297-5-maxime@xxxxxxxxxx Stable-dep-of: 81adbd3ff21c ("drm: adv7511: Fix use-after-free in adv7533_attach_dsi()") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/drm_mipi_dsi.c | 35 ++++++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 1 + 2 files changed, 36 insertions(+) diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c index e53a5b14b47b..468a3a7cb6a5 100644 --- a/drivers/gpu/drm/drm_mipi_dsi.c +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -405,6 +405,41 @@ int mipi_dsi_detach(struct mipi_dsi_device *dsi) } EXPORT_SYMBOL(mipi_dsi_detach); +static void devm_mipi_dsi_detach(void *arg) +{ + struct mipi_dsi_device *dsi = arg; + + mipi_dsi_detach(dsi); +} + +/** + * devm_mipi_dsi_attach - Attach a MIPI-DSI device to its DSI Host + * @dev: device to tie the MIPI-DSI device attachment lifetime to + * @dsi: DSI peripheral + * + * This is the managed version of mipi_dsi_attach() which automatically + * calls mipi_dsi_detach() when @dev is unbound. + * + * Returns: + * 0 on success, a negative error code on failure. + */ +int devm_mipi_dsi_attach(struct device *dev, + struct mipi_dsi_device *dsi) +{ + int ret; + + ret = mipi_dsi_attach(dsi); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, devm_mipi_dsi_detach, dsi); + if (ret) + return ret; + + return 0; +} +EXPORT_SYMBOL_GPL(devm_mipi_dsi_attach); + static ssize_t mipi_dsi_device_transfer(struct mipi_dsi_device *dsi, struct mipi_dsi_msg *msg) { diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index af8ed48749eb..75995f3f2099 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -230,6 +230,7 @@ devm_mipi_dsi_device_register_full(struct device *dev, struct mipi_dsi_host *hos struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node *np); int mipi_dsi_attach(struct mipi_dsi_device *dsi); int mipi_dsi_detach(struct mipi_dsi_device *dsi); +int devm_mipi_dsi_attach(struct device *dev, struct mipi_dsi_device *dsi); int mipi_dsi_shutdown_peripheral(struct mipi_dsi_device *dsi); int mipi_dsi_turn_on_peripheral(struct mipi_dsi_device *dsi); int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi, -- 2.39.5
