[PATCH 6.1.y 2/2] net: dsa: realtek: use gpiod_set_value_cansleep for reset GPIO

[Sasha Levin <sashal@kernel.org>]

From: Ahmad Fatoum <a.fatoum@pengutronix.de>

[ Upstream commit fb58b6a696b30bcbfbe0cfc0a91b19c816a955fc ]

rtl83xx_reset_assert() and rtl83xx_reset_deassert() are only called from
the probe path, which may sleep and is not timing-critical.  When the
reset GPIO is provided by a sleeping controller such as an I2C I/O
expander, gpiod_set_value() warns:

  WARNING: drivers/gpio/gpiolib.c:4030 at gpiod_set_value+0x44/0x80, CPU#1: kworker/u16:4/61
  Hardware name: B&O MAP CA33 Rev f (UNKNOWN) (DT)
  Workqueue: events_unbound deferred_probe_work_func
  pc : gpiod_set_value+0x44/0x80
  lr : rtl83xx_probe+0x1d8/0x3a0
  Call trace:
   gpiod_set_value+0x44/0x80 (P)
   rtl83xx_probe+0x1d8/0x3a0
   realtek_mdio_probe+0x24/0xa0
   mdio_probe+0x38/0x78
   really_probe+0xc4/0x3e0
   __driver_probe_device+0x15c/0x1b8
   driver_probe_device+0xb4/0x120
   __device_attach_driver+0xb8/0x1a0
   bus_for_each_drv+0x88/0xf0
   __device_attach+0xa0/0x1d8
   device_initial_probe+0x54/0x68
   bus_probe_device+0x38/0xa0
   deferred_probe_work_func+0xb8/0x120
   process_one_work+0x184/0x4e8
   worker_thread+0x188/0x308
   kthread+0x130/0x150
   ret_from_fork+0x10/0x20

Switch both helpers to gpiod_set_value_cansleep() so such a reset GPIO can
be used without triggering the warning.

The reset GPIO has been driven with the non-sleeping gpiod_set_value()
since the driver was added in v4.19.  The call has since been refactored
across several files - from realtek-smi.c / realtek-mdio.c into the common
rtl83xx.c module and then into the rtl83xx_reset_assert() and
rtl83xx_reset_deassert() helpers (both in v6.9).  This patch therefore
applies as-is only to kernels that carry those helpers (v6.9+); older
stable kernels need the same gpiod_set_value_cansleep() conversion at the
corresponding open-coded call sites.

Fixes: d8652956cf37 ("net: dsa: realtek-smi: Add Realtek SMI driver")
Cc: <stable@vger.kernel.org> # 6.9.x
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Co-developed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Alvin Šipraga <alvin.sipraga@analog.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
Link: https://patch.msgid.link/20260814110102.2362246-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/dsa/realtek/realtek-mdio.c | 4 ++--
 drivers/net/dsa/realtek/realtek-smi.c  | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/dsa/realtek/realtek-mdio.c b/drivers/net/dsa/realtek/realtek-mdio.c
index aefb734e6f006..fc0559d02f1e6 100644
--- a/drivers/net/dsa/realtek/realtek-mdio.c
+++ b/drivers/net/dsa/realtek/realtek-mdio.c
@@ -202,10 +202,10 @@ static int realtek_mdio_probe(struct mdio_device *mdiodev)
 	}
 
 	if (priv->reset) {
-		gpiod_set_value(priv->reset, 1);
+		gpiod_set_value_cansleep(priv->reset, 1);
 		dev_dbg(dev, "asserted RESET\n");
 		msleep(REALTEK_HW_STOP_DELAY);
-		gpiod_set_value(priv->reset, 0);
+		gpiod_set_value_cansleep(priv->reset, 0);
 		msleep(REALTEK_HW_START_DELAY);
 		dev_dbg(dev, "deasserted RESET\n");
 	}
diff --git a/drivers/net/dsa/realtek/realtek-smi.c b/drivers/net/dsa/realtek/realtek-smi.c
index c07c99bf1cd1e..11ae9fe6fa68e 100644
--- a/drivers/net/dsa/realtek/realtek-smi.c
+++ b/drivers/net/dsa/realtek/realtek-smi.c
@@ -464,10 +464,10 @@ static int realtek_smi_probe(struct platform_device *pdev)
 		return PTR_ERR(priv->reset);
 	}
 	if (priv->reset) {
-		gpiod_set_value(priv->reset, 1);
+		gpiod_set_value_cansleep(priv->reset, 1);
 		dev_dbg(dev, "asserted RESET\n");
 		msleep(REALTEK_HW_STOP_DELAY);
-		gpiod_set_value(priv->reset, 0);
+		gpiod_set_value_cansleep(priv->reset, 0);
 		msleep(REALTEK_HW_START_DELAY);
 		dev_dbg(dev, "deasserted RESET\n");
 	}
-- 
2.53.0