6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Frank Li Frank.Li@nxp.com
commit 5e5e3c92e748a6d859190e123b9193cf4911fcca upstream.
┌─────┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┌───── SCL: ┘ └─────┛ └──┛ └──┛ └──┛ └──┛ └──┛ └──┛ └──┛ └──┘ ───┐ ┌─────┐ ┌─────┐ ┌───────────┐ SDA: └───────────────────────┘ └─────┘ └─────┘ └───── xxx╱ ╲╱ ╲╱ ╲╱ ╲╱ ╲ : xxx╲IBI ╱╲ Addr(0x0a) ╱╲ RW ╱╲NACK╱╲ S ╱
If an In-Band Interrupt (IBI) occurs and IBI work thread is not immediately scheduled, when svc_i3c_master_priv_xfers() initiates the I3C transfer and attempts to send address 0x7e, the target interprets it as an IBI handler and returns the target address 0x0a.
However, svc_i3c_master_priv_xfers() does not handle this case and proceeds with other transfers, resulting in incorrect data being returned.
Add IBIWON check in svc_i3c_master_xfer(). In case this situation occurs, return a failure to the driver.
Fixes: dd3c52846d59 ("i3c: master: svc: Add Silvaco I3C master driver") Cc: stable@vger.kernel.org Reviewed-by: Miquel Raynal miquel.raynal@bootlin.com Signed-off-by: Frank Li Frank.Li@nxp.com Link: https://lore.kernel.org/r/20231023161658.3890811-3-Frank.Li@nxp.com Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i3c/master/svc-i3c-master.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)
--- a/drivers/i3c/master/svc-i3c-master.c +++ b/drivers/i3c/master/svc-i3c-master.c @@ -1011,6 +1011,9 @@ static int svc_i3c_master_xfer(struct sv u32 reg; int ret;
+ /* clean SVC_I3C_MINT_IBIWON w1c bits */ + writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS); + writel(SVC_I3C_MCTRL_REQUEST_START_ADDR | xfer_type | SVC_I3C_MCTRL_IBIRESP_NACK | @@ -1028,6 +1031,23 @@ static int svc_i3c_master_xfer(struct sv ret = -ENXIO; goto emit_stop; } + + /* + * According to I3C spec ver 1.1.1, 5.1.2.2.3 Consequence of Controller Starting a Frame + * with I3C Target Address. + * + * The I3C Controller normally should start a Frame, the Address may be arbitrated, and so + * the Controller shall monitor to see whether an In-Band Interrupt request, a Controller + * Role Request (i.e., Secondary Controller requests to become the Active Controller), or + * a Hot-Join Request has been made. + * + * If missed IBIWON check, the wrong data will be return. When IBIWON happen, return failure + * and yield the above events handler. + */ + if (SVC_I3C_MSTATUS_IBIWON(reg)) { + ret = -ENXIO; + goto emit_stop; + }
if (rnw) ret = svc_i3c_master_read(master, in, xfer_len);