bus: mhi: pci_generic: No-Op for device_wake operations
The wake_db register presence is highly speculative and can fuze MHI devices. Indeed, currently the wake_db register address is defined at entry 127 of the 'Channel doorbell array', thus writing to this address is equivalent to ringing the doorbell for channel 127, causing trouble with some devics (e.g. SDX24 based modems) that get an unexpected channel 127 doorbell interrupt. This change fixes that issue by setting wake get/put as no-op for pci_generic devices. The wake device sideband mechanism seems really specific to each device, and is AFAIK not defined by the MHI spec. It also removes zeroing initialization of wake_db register during MMIO initialization, the register being set via wake_get/put accessors few cycles later during M0 transition. Signed-off-by:Loic Poulain <loic.poulain@linaro.org> Reviewed-by:
Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/1614971808-22156-4-git-send-email-loic.poulain@linaro.org Signed-off-by:
Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
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59d05b71