diff options
| author | Clark Wang <xiaoning.wang@nxp.com> | 2023-05-17 11:30:30 +0800 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2023-06-05 00:50:51 +0200 |
| commit | 49b472ebc61de3d4aa7cc57539246bb39f6c5128 (patch) | |
| tree | ef827a217b4254e1f801c561b11774cc8b16daec /drivers/i3c | |
| parent | 33beadb3b1ab74e69db2c49d9663f3a93a273943 (diff) | |
| download | linux-49b472ebc61de3d4aa7cc57539246bb39f6c5128.tar.gz | |
i3c: master: svc: add NACK check after start byte sent
Add NACK check after start byte is sent.
It is possible to detect early that a device is not on the bus
and avoid invalid transmissions thereafter.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20230517033030.3068085-3-xiaoning.wang@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/i3c')
| -rw-r--r-- | drivers/i3c/master/svc-i3c-master.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c index 4edf33ed207d0..0d63b732ef0c8 100644 --- a/drivers/i3c/master/svc-i3c-master.c +++ b/drivers/i3c/master/svc-i3c-master.c @@ -92,6 +92,7 @@ #define SVC_I3C_MINTCLR 0x094 #define SVC_I3C_MINTMASKED 0x098 #define SVC_I3C_MERRWARN 0x09C +#define SVC_I3C_MERRWARN_NACK BIT(2) #define SVC_I3C_MDMACTRL 0x0A0 #define SVC_I3C_MDATACTRL 0x0AC #define SVC_I3C_MDATACTRL_FLUSHTB BIT(0) @@ -1014,6 +1015,11 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, if (ret) goto emit_stop; + if (readl(master->regs + SVC_I3C_MERRWARN) & SVC_I3C_MERRWARN_NACK) { + ret = -ENXIO; + goto emit_stop; + } + if (rnw) ret = svc_i3c_master_read(master, in, xfer_len); else |