linux-dev/drivers/bus/mhi/ep, branch master

bus: mhi: ep: Check dev_set_name() return value

2022-07-09T06:27:54Z

It's possible that dev_set_name() returns -ENOMEM, catch and handle this. Signed-off-by: Bo Liu Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220708015948.4091-1-liubo03@inspur.com Signed-off-by: Manivannan Sadhasivam

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

2022-04-26T11:17:42Z

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 Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-19-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for suspending and resuming channels

2022-04-26T11:17:42Z

Add support for suspending and resuming the channels in MHI endpoint stack. The channels will be moved to the suspended state during M3 state transition and will be resumed during M0 transition. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-18-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for queueing SKBs to the host

2022-04-26T11:17:42Z

Add support for queueing SKBs to the host over the transfer ring of the relevant channel. The mhi_ep_queue_skb() API will be used by the client networking drivers to queue the SKBs to the host over MHI bus. The host will add ring elements to the transfer ring periodically for the device and the device will write SKBs to the ring elements. If a single SKB doesn't fit in a ring element (TRE), it will be placed in multiple ring elements and the overflow event will be sent for all ring elements except the last one. For the last ring element, the EOT event will be sent indicating the packet boundary. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-17-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for processing channel rings

2022-04-26T11:17:41Z

Add support for processing the channel rings from host. For the channel ring associated with DL channel, the xfer callback will simply invoked. For the case of UL channel, the ring elements will be read in a buffer till the write pointer and later passed to the client driver using the xfer callback. The client drivers should provide the callbacks for both UL and DL channels during registration. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-16-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for reading from the host

2022-04-26T11:17:41Z

Data transfer between host and the ep device happens over the transfer ring associated with each bi-directional channel pair. Host defines the transfer ring by allocating memory for it. The read and write pointer addresses of the transfer ring are stored in the channel context. Once host places the elements in the transfer ring, it increments the write pointer and rings the channel doorbell. Device will receive the doorbell interrupt and will process the transfer ring elements. This commit adds support for reading the transfer ring elements from the transfer ring till write pointer, incrementing the read pointer and finally sending the completion event to the host through corresponding event ring. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-15-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for processing command rings

2022-04-26T11:17:41Z

Add support for processing the command rings. Command ring is used by the host to issue channel specific commands to the ep device. Following commands are supported: 1. Start channel 2. Stop channel 3. Reset channel Once the device receives the command doorbell interrupt from host, it executes the command and generates a command completion event to the host in the primary event ring. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-14-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for handling SYS_ERR condition

2022-04-26T11:17:41Z

Add support for handling SYS_ERR (System Error) condition in the MHI endpoint stack. The SYS_ERR flag will be asserted by the endpoint device when it detects an internal error. The host will then issue reset and reinitializes MHI to recover from the error state. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-13-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for handling MHI_RESET

2022-04-26T11:17:41Z

Add support for handling MHI_RESET in MHI endpoint stack. MHI_RESET will be issued by the host during shutdown and during error scenario so that it can recover the endpoint device without restarting the whole device. MHI_RESET handling involves resetting the internal MHI registers, data structures, state machines, resetting all channels/rings and setting MHICTRL.RESET bit to 0. Additionally the device will also move to READY state if the reset was due to SYS_ERR. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-12-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman

bus: mhi: ep: Add support for powering down the MHI endpoint stack

2022-04-26T11:17:41Z

Add support for MHI endpoint power_down that includes stopping all available channels, destroying the channels, resetting the event and transfer rings and freeing the host cache. The stack will be powered down whenever the physical bus link goes down. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-11-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman