5.10-stable review patch. If anyone has any objections, please let me know.
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From: Maxime Ripard maxime@cerno.tech
[ Upstream commit a1419fb4a73e47f0eab2985dff594ed52397471b ]
Devices that take their data through the MIPI-DSI bus but are controlled through a secondary bus like I2C have to register a secondary device on the MIPI-DSI bus through the mipi_dsi_device_register_full() function.
At removal or when an error occurs, that device needs to be removed through a call to mipi_dsi_device_unregister().
Let's create a device-managed variant of the registration function that will automatically unregister the device at unbind.
Reviewed-by: Andrzej Hajda a.hajda@samsung.com Signed-off-by: Maxime Ripard maxime@cerno.tech Link: https://patchwork.freedesktop.org/patch/msgid/20210910101218.1632297-4-maxim... Stable-dep-of: 81adbd3ff21c ("drm: adv7511: Fix use-after-free in adv7533_attach_dsi()") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/drm_mipi_dsi.c | 46 ++++++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 3 +++ 2 files changed, 49 insertions(+)
diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c index 107a98484f50..e53a5b14b47b 100644 --- a/drivers/gpu/drm/drm_mipi_dsi.c +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -246,6 +246,52 @@ void mipi_dsi_device_unregister(struct mipi_dsi_device *dsi) } EXPORT_SYMBOL(mipi_dsi_device_unregister);
+static void devm_mipi_dsi_device_unregister(void *arg) +{ + struct mipi_dsi_device *dsi = arg; + + mipi_dsi_device_unregister(dsi); +} + +/** + * devm_mipi_dsi_device_register_full - create a managed MIPI DSI device + * @dev: device to tie the MIPI-DSI device lifetime to + * @host: DSI host to which this device is connected + * @info: pointer to template containing DSI device information + * + * Create a MIPI DSI device by using the device information provided by + * mipi_dsi_device_info template + * + * This is the managed version of mipi_dsi_device_register_full() which + * automatically calls mipi_dsi_device_unregister() when @dev is + * unbound. + * + * Returns: + * A pointer to the newly created MIPI DSI device, or, a pointer encoded + * with an error + */ +struct mipi_dsi_device * +devm_mipi_dsi_device_register_full(struct device *dev, + struct mipi_dsi_host *host, + const struct mipi_dsi_device_info *info) +{ + struct mipi_dsi_device *dsi; + int ret; + + dsi = mipi_dsi_device_register_full(host, info); + if (IS_ERR(dsi)) + return dsi; + + ret = devm_add_action_or_reset(dev, + devm_mipi_dsi_device_unregister, + dsi); + if (ret) + return ERR_PTR(ret); + + return dsi; +} +EXPORT_SYMBOL_GPL(devm_mipi_dsi_device_register_full); + static DEFINE_MUTEX(host_lock); static LIST_HEAD(host_list);
diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index 0dbed65c0ca5..af8ed48749eb 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -224,6 +224,9 @@ struct mipi_dsi_device * mipi_dsi_device_register_full(struct mipi_dsi_host *host, const struct mipi_dsi_device_info *info); void mipi_dsi_device_unregister(struct mipi_dsi_device *dsi); +struct mipi_dsi_device * +devm_mipi_dsi_device_register_full(struct device *dev, struct mipi_dsi_host *host, + const struct mipi_dsi_device_info *info); 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);