Commit 4dd12e94 authored by Stanley Chu's avatar Stanley Chu Committed by Alexandre Belloni
Browse files

i3c: master: svc: Fix npcm845 invalid slvstart event 



I3C HW may generate an invalid SlvStart event when emitting a STOP.
If it is a true SlvStart, the MSTATUS state is SLVREQ. Check the
MSTATUS state to ignore the false event.

Reviewed-by: default avatarFrank Li <Frank.Li@nxp.com>
Signed-off-by: default avatarStanley Chu <yschu@nuvoton.com>
Link: https://lore.kernel.org/r/20250306075429.2265183-5-yschu@nuvoton.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 4008a74e

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

+14 −1
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ 
#define SVC_I3C_MSTATUS      0x088

#define   SVC_I3C_MSTATUS_STATE(x) FIELD_GET(GENMASK(2, 0), (x))

#define   SVC_I3C_MSTATUS_STATE_DAA(x) (SVC_I3C_MSTATUS_STATE(x) == 5)

#define   SVC_I3C_MSTATUS_STATE_SLVREQ(x) (SVC_I3C_MSTATUS_STATE(x) == 1)

#define   SVC_I3C_MSTATUS_STATE_IDLE(x) (SVC_I3C_MSTATUS_STATE(x) == 0)

#define   SVC_I3C_MSTATUS_BETWEEN(x) FIELD_GET(BIT(4), (x))

#define   SVC_I3C_MSTATUS_NACKED(x) FIELD_GET(BIT(5), (x))
@@ -143,6 +144,12 @@ 
 * Fill the FIFO in advance to prevent FIFO from becoming empty.

 */

#define SVC_I3C_QUIRK_FIFO_EMPTY	BIT(0)

/*

 * SVC_I3C_QUIRK_FLASE_SLVSTART:

 * I3C HW may generate an invalid SlvStart event when emitting a STOP.

 * If it is a true SlvStart, the MSTATUS state is SLVREQ.

 */

#define SVC_I3C_QUIRK_FALSE_SLVSTART	BIT(1)



struct svc_i3c_cmd {

	u8 addr;
@@ -586,6 +593,11 @@ static irqreturn_t svc_i3c_master_irq_handler(int irq, void *dev_id) 
	/* Clear the interrupt status */

	writel(SVC_I3C_MINT_SLVSTART, master->regs + SVC_I3C_MSTATUS);



	/* Ignore the false event */

	if (svc_has_quirk(master, SVC_I3C_QUIRK_FALSE_SLVSTART) &&

	    !SVC_I3C_MSTATUS_STATE_SLVREQ(active))

		return IRQ_HANDLED;



	svc_i3c_master_disable_interrupts(master);



	/* Handle the interrupt in a non atomic context */
@@ -2020,7 +2032,8 @@ static const struct dev_pm_ops svc_i3c_pm_ops = { 
};



static const struct svc_i3c_drvdata npcm845_drvdata = {

	.quirks = SVC_I3C_QUIRK_FIFO_EMPTY,

	.quirks = SVC_I3C_QUIRK_FIFO_EMPTY |

		SVC_I3C_QUIRK_FALSE_SLVSTART,

};



static const struct svc_i3c_drvdata svc_default_drvdata = {};