Commit 8b56f98b authored by Charles Boyer's avatar Charles Boyer Committed by Andi Shyti
Browse files

i2c: npcm: Enable slave in eob interrupt 



Nuvoton slave enable was in user space API call master_xfer, so it is
subject to delays from the OS scheduler. If the BMC is not enabled for
slave mode in time for master to send response, then it will NAK the
address match. Then the PLDM request timeout occurs.

If the slave enable is moved to the EOB interrupt service routine, then
the BMC can be ready in slave mode by the time it needs to receive a
response.

Signed-off-by: default avatarCharles Boyer <Charles.Boyer@fii-usa.com>
Signed-off-by: default avatarVivekanand Veeracholan <vveerach@google.com>
Signed-off-by: default avatarTyrone Ting <kfting@nuvoton.com>
Reviewed-by: default avatarTali Perry <tali.perry1@gmail.com>
Link: https://lore.kernel.org/r/20241219090859.18722-5-kfting@nuvoton.com


Signed-off-by: default avatarAndi Shyti <andi.shyti@kernel.org>
parent 6ddc9132

drivers/i2c/busses/i2c-npcm7xx.c

+6 −0
Original line number Diff line number Diff line
@@ -1925,6 +1925,12 @@ static int npcm_i2c_int_master_handler(struct npcm_i2c *bus) 
	    (FIELD_GET(NPCM_I2CCST3_EO_BUSY,

		       ioread8(bus->reg + NPCM_I2CCST3)))) {

		npcm_i2c_irq_handle_eob(bus);

#if IS_ENABLED(CONFIG_I2C_SLAVE)

		/* reenable slave if it was enabled */

		if (bus->slave)

			iowrite8(bus->slave->addr | NPCM_I2CADDR_SAEN,

				 bus->reg + NPCM_I2CADDR1);

#endif

		return 0;

	}