bus: mhi: ep: Add uevent support for module autoloading

Add uevent support to MHI endpoint bus so that the client drivers can be
autoloaded by udev when the MHI endpoint devices gets created. The client
drivers are expected to provide MODULE_DEVICE_TABLE with the MHI id_table
struct so that the alias can be exported.

The MHI endpoint reused the mhi_device_id structure of the MHI bus.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-19-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c
index bae5f40ec15e50e7fa5193835556ecb0d2c7e186..40109a79017a2a6f57f50a4f633fb6b62af59a62 100644 (file)
--- a/drivers/bus/mhi/ep/main.c
+++ b/drivers/bus/mhi/ep/main.c
@@ -1536,6 +1536,14 @@ void mhi_ep_driver_unregister(struct mhi_ep_driver *mhi_drv)
 }
 EXPORT_SYMBOL_GPL(mhi_ep_driver_unregister);
 
+static int mhi_ep_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+       struct mhi_ep_device *mhi_dev = to_mhi_ep_device(dev);
+
+       return add_uevent_var(env, "MODALIAS=" MHI_EP_DEVICE_MODALIAS_FMT,
+                                       mhi_dev->name);
+}
+
 static int mhi_ep_match(struct device *dev, struct device_driver *drv)
 {
        struct mhi_ep_device *mhi_dev = to_mhi_ep_device(dev);
@@ -1562,6 +1570,7 @@ struct bus_type mhi_ep_bus_type = {
        .name = "mhi_ep",
        .dev_name = "mhi_ep",
        .match = mhi_ep_match,
+       .uevent = mhi_ep_uevent,
 };
 
 static int __init mhi_ep_init(void)

diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 5da5d990ff58ab5c82de80684f0304ec86a24a20..549590e9c644d930c81c7ce968b873aa62f2fbe0 100644 (file)
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -835,6 +835,8 @@ struct wmi_device_id {
 #define MHI_DEVICE_MODALIAS_FMT "mhi:%s"
 #define MHI_NAME_SIZE 32
 
+#define MHI_EP_DEVICE_MODALIAS_FMT "mhi_ep:%s"
+
 /**
  * struct mhi_device_id - MHI device identification
  * @chan: MHI channel name

diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 5258247d78ac29765337e7cf4d09afeb05e1e0d4..d9d6a31446eaa66320850652a2a50a5ca0d5e7c5 100644 (file)
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1391,6 +1391,15 @@ static int do_mhi_entry(const char *filename, void *symval, char *alias)
        return 1;
 }
 
+/* Looks like: mhi_ep:S */
+static int do_mhi_ep_entry(const char *filename, void *symval, char *alias)
+{
+       DEF_FIELD_ADDR(symval, mhi_device_id, chan);
+       sprintf(alias, MHI_EP_DEVICE_MODALIAS_FMT, *chan);
+
+       return 1;
+}
+
 /* Looks like: ishtp:{guid} */
 static int do_ishtp_entry(const char *filename, void *symval, char *alias)
 {
@@ -1519,6 +1528,7 @@ static const struct devtable devtable[] = {
        {"tee", SIZE_tee_client_device_id, do_tee_entry},
        {"wmi", SIZE_wmi_device_id, do_wmi_entry},
        {"mhi", SIZE_mhi_device_id, do_mhi_entry},
+       {"mhi_ep", SIZE_mhi_device_id, do_mhi_ep_entry},
        {"auxiliary", SIZE_auxiliary_device_id, do_auxiliary_entry},
        {"ssam", SIZE_ssam_device_id, do_ssam_entry},
        {"dfl", SIZE_dfl_device_id, do_dfl_entry},