[PATCH v7 1/2] firmware: ti_sci: Support transfers without response

[Kendall Willis]

On 11:19-20250812, Markus Schneider-Pargmann wrote:
> Check the header flags if an response is expected or not. If it is not
> expected skip the receive part of ti_sci_do_xfer(). This prepares the
> driver for one-way messages as prepare_sleep for Partial-IO.
> 
> Signed-off-by: Markus Schneider-Pargmann <msp at baylibre.com>
> ---
>  drivers/firmware/ti_sci.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
> index ae5fd1936ad322e5e3a94897cc042f6548f919e6..c187fb714b3a4c658d0593c844716d4b160e4fa9 100644
> --- a/drivers/firmware/ti_sci.c
> +++ b/drivers/firmware/ti_sci.c
> @@ -398,6 +398,9 @@ static void ti_sci_put_one_xfer(struct ti_sci_xfers_info *minfo,
>  static inline int ti_sci_do_xfer(struct ti_sci_info *info,
>  				 struct ti_sci_xfer *xfer)
>  {
> +	struct ti_sci_msg_hdr *hdr = (struct ti_sci_msg_hdr *)xfer->tx_message.buf;
> +	bool response_expected = !!(hdr->flags & (TI_SCI_FLAG_REQ_ACK_ON_PROCESSED |
> +						  TI_SCI_FLAG_REQ_ACK_ON_RECEIVED));
>  	int ret;
>  	int timeout;
>  	struct device *dev = info->dev;
> @@ -409,12 +412,12 @@ static inline int ti_sci_do_xfer(struct ti_sci_info *info,
>  
>  	ret = 0;
>  
> -	if (system_state <= SYSTEM_RUNNING) {
> +	if (response_expected && system_state <= SYSTEM_RUNNING) {
>  		/* And we wait for the response. */
>  		timeout = msecs_to_jiffies(info->desc->max_rx_timeout_ms);
>  		if (!wait_for_completion_timeout(&xfer->done, timeout))
>  			ret = -ETIMEDOUT;
> -	} else {
> +	} else if (response_expected) {
>  		/*
>  		 * If we are !running, we cannot use wait_for_completion_timeout
>  		 * during noirq phase, so we must manually poll the completion.
> 
> -- 
> 2.50.1
>

Reviewed-by: Kendall Willis <k-willis at ti.com>

Best,
Kendall Willis