Commit 3a36273e authored by Stanley Chu's avatar Stanley Chu Committed by Alexandre Belloni
Browse files

i3c: master: svc: Prevent incomplete IBI transaction 



If no free IBI slot is available, svc_i3c_master_handle_ibi returns
immediately. This causes the STOP condition to be missed because the
EmitStop request is sent when the transfer is not complete. To resolve
this, svc_i3c_master_handle_ibi must wait for the transfer to complete
before returning.

Fixes: dd3c5284 ("i3c: master: svc: Add Silvaco I3C master driver")
Signed-off-by: default avatarStanley Chu <yschu@nuvoton.com>
Reviewed-by: default avatarFrank Li <Frank.Li@nxp.com>
Reviewed-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://patch.msgid.link/20251027034715.708243-1-yschu@nuvoton.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 9d4f2198

drivers/i3c/master/svc-i3c-master.c

+14 −8
Original line number Diff line number Diff line
@@ -406,21 +406,27 @@ static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master, 
	int ret, val;

	u8 *buf;



	slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);

	if (!slot)

		return -ENOSPC;



	slot->len = 0;

	buf = slot->data;



	/*

	 * Wait for transfer to complete before returning. Otherwise, the EmitStop

	 * request might be sent when the transfer is not complete.

	 */

	ret = readl_relaxed_poll_timeout(master->regs + SVC_I3C_MSTATUS, val,

						SVC_I3C_MSTATUS_COMPLETE(val), 0, 1000);

	if (ret) {

		dev_err(master->dev, "Timeout when polling for COMPLETE\n");

		i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);

		return ret;

	}



	slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);

	if (!slot) {

		dev_dbg(master->dev, "No free ibi slot, drop the data\n");

		writel(SVC_I3C_MDATACTRL_FLUSHRB, master->regs + SVC_I3C_MDATACTRL);

		return -ENOSPC;

	}



	slot->len = 0;

	buf = slot->data;



	while (SVC_I3C_MSTATUS_RXPEND(readl(master->regs + SVC_I3C_MSTATUS))  &&

	       slot->len < SVC_I3C_FIFO_SIZE) {

		mdatactrl = readl(master->regs + SVC_I3C_MDATACTRL);