[PATCH v5 05/17] i3c: renesas: Reset the controller on resume

From: Claudiu Beznea <[email protected]>

Reset the controller on resume after enabling the clocks to follow the
same sequence as in probe and avoid potential ordering related failures.

With it, renesas_i3c_reset() was updated to use read_poll_timeout_atomic(),
as the driver's resume callback is executed during the noirq phase of
resume, where interrupts are disabled.

Fixes: e7218986319b ("i3c: renesas: Add suspend/resume support")
Cc: [email protected]
Reviewed-by: Frank Li <[email protected]>
Signed-off-by: Claudiu Beznea <[email protected]>
---

Changes in v5:
- none

Changes in v4:
- none

Changes in v3:
- collected tags

Changes in v2:
- replaced the read_poll_timeout() in renesas_i3c_reset() with
  read_poll_timeout_atomic() as the renesas_i3c_reset() is called
  in noirq phase of the suspend/resume; updated the patch description
  to reflect that
- collected Frank's tag. Frank, please let me know if this should be
  dropped. Thanks!

 drivers/i3c/master/renesas-i3c.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
index 517ac2df9bd4..6590da962592 100644
--- a/drivers/i3c/master/renesas-i3c.c
+++ b/drivers/i3c/master/renesas-i3c.c
@@ -495,8 +495,8 @@ static int renesas_i3c_reset(struct renesas_i3c *i3c)
 	renesas_writel(i3c->regs, BCTL, 0);
 	renesas_set_bit(i3c->regs, RSTCTL, RSTCTL_RI3CRST);
 
-	return read_poll_timeout(renesas_readl, val, !(val & RSTCTL_RI3CRST),
-				 0, 1000, false, i3c->regs, RSTCTL);
+	return read_poll_timeout_atomic(renesas_readl, val, !(val & RSTCTL_RI3CRST),
+					0, 1000, false, i3c->regs, RSTCTL);
 }
 
 static void renesas_i3c_hw_init(struct renesas_i3c *i3c)
@@ -1483,6 +1483,10 @@ static int renesas_i3c_resume_noirq(struct device *dev)
 	if (ret)
 		goto err_presetn;
 
+	ret = renesas_i3c_reset(i3c);
+	if (ret)
+		goto err_clks_disable;
+
 	/* Re-store I3C registers value. */
 	renesas_writel(i3c->regs, STDBR, i3c->i3c_STDBR);
 	renesas_writel(i3c->regs, EXTBR, i3c->extbr);
@@ -1502,6 +1506,8 @@ static int renesas_i3c_resume_noirq(struct device *dev)
 
 	return 0;
 
+err_clks_disable:
+	clk_bulk_disable(i3c->num_clks, i3c->clks);
 err_presetn:
 	reset_control_assert(i3c->presetn);
 err_tresetn:
-- 
2.43.0


-- 
linux-i3c mailing list
[email protected]
http://lists.infradead.org/mailman/listinfo/linux-i3c