Re: [PATCH v5 4/9] bus: mhi: core: Clear configuration from channel context during reset

[Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>]

On Fri, Jan 08, 2021 at 12:54:52PM -0800, Bhaumik Bhatt wrote:
> When clearing up the channel context after client drivers are
> done using channels, the configuration is currently not being
> reset entirely. Ensure this is done to appropriately handle
> issues where clients unaware of the context state end up calling
> functions which expect a context.
> 
> Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
> Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Thanks,
Mani

> ---
>  drivers/bus/mhi/core/init.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index 482b365..30eef19 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -558,6 +558,7 @@ void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
>  	struct mhi_ring *buf_ring;
>  	struct mhi_ring *tre_ring;
>  	struct mhi_chan_ctxt *chan_ctxt;
> +	u32 tmp;
>  
>  	buf_ring = &mhi_chan->buf_ring;
>  	tre_ring = &mhi_chan->tre_ring;
> @@ -568,7 +569,19 @@ void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
>  	vfree(buf_ring->base);
>  
>  	buf_ring->base = tre_ring->base = NULL;
> +	tre_ring->ctxt_wp = NULL;
>  	chan_ctxt->rbase = 0;
> +	chan_ctxt->rlen = 0;
> +	chan_ctxt->rp = 0;
> +	chan_ctxt->wp = 0;
> +
> +	tmp = chan_ctxt->chcfg;
> +	tmp &= ~CHAN_CTX_CHSTATE_MASK;
> +	tmp |= (MHI_CH_STATE_DISABLED << CHAN_CTX_CHSTATE_SHIFT);
> +	chan_ctxt->chcfg = tmp;
> +
> +	/* Update to all cores */
> +	smp_wmb();
>  }
>  
>  int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
> -- 
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