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path: root/drivers/core/devres.c
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* devres: add debug command to dump device resourcesMasahiro Yamada2015-08-06-0/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This new command can dump all device resources associated to each device. The fields in every line shows: - The address of the resource - The size of the resource - The name of the release function - The stage in which the resource has been acquired (BIND/PROBE) Currently, there is no driver using devres, but if such drivers are implemented, the output of this command should look like this: => dm devres - root_driver - soc - extbus - serial@54006800 bfb541e8 (8 byte) devm_kmalloc_release BIND bfb54440 (4 byte) devm_kmalloc_release PROBE bfb54460 (4 byte) devm_kmalloc_release PROBE - serial@54006900 bfb54270 (8 byte) devm_kmalloc_release BIND - gpio@55000000 - i2c@58780000 bfb5bce8 (12 byte) devm_kmalloc_release PROBE bfb5bd10 (4 byte) devm_kmalloc_release PROBE - eeprom bfb54418 (12 byte) devm_kmalloc_release BIND Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Simon Glass <sjg@chromium.org>
* devres: add devm_kmalloc() and friends (managed memory allocators)Masahiro Yamada2015-08-06-0/+34
| | | | | | | | | | | devm_kmalloc() is identical to kmalloc() except that the memory allocated with it is managed and will be automatically released when the device is removed/unbound. Likewise for the other variants. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Simon Glass <sjg@chromium.org>
* devres: introduce Devres (Managed Device Resource) frameworkMasahiro Yamada2015-08-06-0/+196
In U-Boot's driver model, memory is basically allocated and freed in the core framework. So, low level drivers generally only have to specify the size of needed memory with .priv_auto_alloc_size, .platdata_auto_alloc_size, etc. Nevertheless, some drivers still need to allocate/free memory on their own in case they cannot statically know the necessary memory size. So, I believe it is reasonable enough to port Devres into U-boot. Devres, which originates in Linux, manages device resources for each device and automatically releases them on driver detach. With devres, device resources are guaranteed to be freed whether initialization fails half-way or the device gets detached. The basic idea is totally the same to that of Linux, but I tweaked it a bit so that it fits in U-Boot's driver model. In U-Boot, drivers are activated in two steps: binding and probing. Binding puts a driver and a device together. It is just data manipulation on the system memory, so nothing has happened on the hardware device at this moment. When the device is really used, it is probed. Probing initializes the real hardware device to make it really ready for use. So, the resources acquired during the probing process must be freed when the device is removed. Likewise, what has been allocated in binding should be released when the device is unbound. The struct devres has a member "probe" to remember when the resource was allocated. CONFIG_DEBUG_DEVRES is also supported for easier debugging. If enabled, debug messages are printed each time a resource is allocated/freed. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Simon Glass <sjg@chromium.org>