Re: [PATCH v8 2/4] dmaengine: qcom: gpi: Add lock/unlock TREs for multi-owner I2C transfers
Mukesh Savaliya <[email protected]>
| Newsgroups | org.kernel.vger.linux-i2c,org.kernel.vger.dmaengine,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On 7/16/2026 5:39 PM, Bartosz Golaszewski wrote: > On Wed, 15 Jul 2026 17:33:40 +0200, Vinod Koul <[email protected]> said: >> On 08-07-26, 10:40, Mukesh Kumar Savaliya wrote: >> >>> +/** >>> + * enum gpi_lock_action - request lock/unlock TRE sequencing >>> + * @GPI_LOCK_NONE: No lock/unlock TRE requested for this transfer >>> + * @GPI_LOCK_ACQUIRE: Emit a lock TRE before the transfer >>> + * @GPI_LOCK_RELEASE: Emit an unlock TRE after the transfer >>> + * >>> + * Used by protocol drivers for multi-owner controller setups (e.g. when >>> + * DeviceTree indicates the controller is shared via qcom,qup-multi-owner). >>> + */ >>> +enum gpi_lock_action { >>> + GPI_LOCK_NONE = 0, >>> + GPI_LOCK_ACQUIRE, >>> + GPI_LOCK_RELEASE, >> >> Can qualcomm people please align on LOCK/UNLOCK interface? This is >> second interface I am seeing now. Can you folks align internally on how >> clients should communicating lock/unlock across different qualcomm >> dmaengine drivers >> > Sure Vinod,Thanks for your review and updating on direction. I thought reverse to not pass transfer index to GSI driver. > As discussed internally - this driver should follow the pattern we established > for BAM DMA where we don't require consumers to be aware of the locking > happening to any larger degree than is absolutely required (for instance: > passing the address of the appropriate scratchpad register as is the case for > BAM DMA). > Yes, Bartosz, i understand. let me align on this and follow BAM DMA design, will review with you OR get BAM DMA changes. If Consumers do not posses knowledge of locking/unlocking, DMA engine (here GSI) need to have some decision making knowledge. e.g. First transfer and last transfer. let me share with you and then will upload. > Bart