5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tony Lindgren <tony@xxxxxxxxxxx>
[ Upstream commit ab4d309d8708035bd323b2e2446eb68cda5e61e5 ]
At least display susbsystem (DSS) has modules with no sysconfig registers
and rely on custom function for module reset handling. Let's make reset
work with that too.
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
Stable-dep-of: 34539b442b3b ("bus: ti-sysc: Flush posted write on enable before reset")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/bus/ti-sysc.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index 44aeceaccfa48..c2808d118568e 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -1809,7 +1809,7 @@ static int sysc_reset(struct sysc *ddata)
sysc_offset = ddata->offsets[SYSC_SYSCONFIG];
- if (ddata->legacy_mode || sysc_offset < 0 ||
+ if (ddata->legacy_mode ||
ddata->cap->regbits->srst_shift < 0 ||
ddata->cfg.quirks & SYSC_QUIRK_NO_RESET_ON_INIT)
return 0;
@@ -1819,9 +1819,11 @@ static int sysc_reset(struct sysc *ddata)
if (ddata->pre_reset_quirk)
ddata->pre_reset_quirk(ddata);
- sysc_val = sysc_read_sysconfig(ddata);
- sysc_val |= sysc_mask;
- sysc_write(ddata, sysc_offset, sysc_val);
+ if (sysc_offset >= 0) {
+ sysc_val = sysc_read_sysconfig(ddata);
+ sysc_val |= sysc_mask;
+ sysc_write(ddata, sysc_offset, sysc_val);
+ }
if (ddata->cfg.srst_udelay)
usleep_range(ddata->cfg.srst_udelay,
--
2.40.1
