[PATCH V3 4/5] i3c: master: svc: set ODSTOP to let I2C device see the STOP signal

From: Clark Wang
Date: Fri Jul 16 2021 - 04:52:27 EST


If using I2C/I3C mixed mode, need to set ODSTOP. Otherwise, the I2C
devices cannot see the stop signal. It may cause message sending errors.

Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
Reviewed-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
---
V2/V3: No change.
---
drivers/i3c/master/svc-i3c-master.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 91358cc5ca07..5677b5b31a86 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -449,7 +449,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
struct i3c_device_info info = {};
unsigned long fclk_rate, fclk_period_ns;
unsigned int high_period_ns, od_low_period_ns;
- u32 ppbaud, pplow, odhpp, odbaud, i2cbaud, reg;
+ u32 ppbaud, pplow, odhpp, odbaud, odstop, i2cbaud, reg;
int ret;

/* Timings derivation */
@@ -479,6 +479,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
switch (bus->mode) {
case I3C_BUS_MODE_PURE:
i2cbaud = 0;
+ odstop = 0;
break;
case I3C_BUS_MODE_MIXED_FAST:
case I3C_BUS_MODE_MIXED_LIMITED:
@@ -487,6 +488,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
* between the high and low period does not really matter.
*/
i2cbaud = DIV_ROUND_UP(1000, od_low_period_ns) - 2;
+ odstop = 1;
break;
case I3C_BUS_MODE_MIXED_SLOW:
/*
@@ -494,6 +496,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
* constraints as the FM+ mode.
*/
i2cbaud = DIV_ROUND_UP(2500, od_low_period_ns) - 2;
+ odstop = 1;
break;
default:
return -EINVAL;
@@ -502,7 +505,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
reg = SVC_I3C_MCONFIG_MASTER_EN |
SVC_I3C_MCONFIG_DISTO(0) |
SVC_I3C_MCONFIG_HKEEP(0) |
- SVC_I3C_MCONFIG_ODSTOP(0) |
+ SVC_I3C_MCONFIG_ODSTOP(odstop) |
SVC_I3C_MCONFIG_PPBAUD(ppbaud) |
SVC_I3C_MCONFIG_PPLOW(pplow) |
SVC_I3C_MCONFIG_ODBAUD(odbaud) |
--
2.25.1