Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 5d882460 authored by Alexander Usyskin's avatar Alexander Usyskin Committed by Greg Kroah-Hartman
Browse files

mei: bus: prevent hardware module unload if device on bus is active 



The hardware module should not be unloaded if the bus
has active devices.
Get get_/put_ bus parent module upon client device
connection/disconnection, to prevent the hardware managing
module to disappear underneath.

Signed-off-by: default avatarAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: default avatarTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 9ecb839f

drivers/misc/mei/bus.c

+31 −0
Original line number Diff line number Diff line
@@ -541,6 +541,37 @@ int mei_cldev_disable(struct mei_cl_device *cldev) 
}

EXPORT_SYMBOL_GPL(mei_cldev_disable);



/**

 * mei_cl_bus_module_get - acquire module of the underlying

 *    hw module.

 *

 * @cl: host client

 *

 * Return: true on success; false if the module was removed.

 */

bool mei_cl_bus_module_get(struct mei_cl *cl)

{

	struct mei_cl_device *cldev = cl->cldev;



	if (!cldev)

		return true;



	return try_module_get(cldev->bus->dev->driver->owner);

}



/**

 * mei_cl_bus_module_put -  release the underlying hw module.

 *

 * @cl: host client

 */

void mei_cl_bus_module_put(struct mei_cl *cl)

{

	struct mei_cl_device *cldev = cl->cldev;



	if (cldev)

		module_put(cldev->bus->dev->driver->owner);

}



/**

 * mei_cl_device_find - find matching entry in the driver id table

 *

drivers/misc/mei/client.c

+8 −2
Original line number Diff line number Diff line
@@ -774,6 +774,8 @@ static void mei_cl_set_disconnected(struct mei_cl *cl) 
	cl->tx_flow_ctrl_creds = 0;

	cl->timer_count = 0;



	mei_cl_bus_module_put(cl);



	if (!cl->me_cl)

		return;
@@ -1077,13 +1079,17 @@ int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl, 


	dev = cl->dev;



	if (!mei_cl_bus_module_get(cl))

		return -ENODEV;



	rets = mei_cl_set_connecting(cl, me_cl);

	if (rets)

		return rets;

		goto nortpm;



	if (mei_cl_is_fixed_address(cl)) {

		cl->state = MEI_FILE_CONNECTED;

		return 0;

		rets = 0;

		goto nortpm;

	}



	rets = pm_runtime_get(dev->dev);

drivers/misc/mei/mei_dev.h

+2 −0
Original line number Diff line number Diff line
@@ -328,6 +328,8 @@ ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length, 
bool mei_cl_bus_rx_event(struct mei_cl *cl);

bool mei_cl_bus_notify_event(struct mei_cl *cl);

void mei_cl_bus_remove_devices(struct mei_device *bus);

bool mei_cl_bus_module_get(struct mei_cl *cl);

void mei_cl_bus_module_put(struct mei_cl *cl);

int mei_cl_bus_init(void);

void mei_cl_bus_exit(void);