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authorFrank Li <Frank.Li@nxp.com>2023-10-23 19:16:54 +0300
committerAlexandre Belloni <alexandre.belloni@bootlin.com>2023-11-03 21:48:17 +0300
commit5e5e3c92e748a6d859190e123b9193cf4911fcca (patch)
tree701e91e22bca65d560ee4359230b6f8cf432e6e4 /drivers
parent6bf3fc268183816856c96b8794cd66146bc27b35 (diff)
downloadlinux-5e5e3c92e748a6d859190e123b9193cf4911fcca.tar.xz
i3c: master: svc: fix wrong data return when IBI happen during start frame
┌─────┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┏──┐ ┌───── 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>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/i3c/master/svc-i3c-master.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 66d1eaa59bd3..2b2b9c948167 100644
--- 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 svc_i3c_master *master,
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 |
@@ -1029,6 +1032,23 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master,
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);
else