[PATCH 5.8 285/464] usb: dwc3: meson-g12a: fix shared reset control use

From: Greg Kroah-Hartman
Date: Mon Aug 17 2020 - 15:29:15 EST


From: Dan Robertson <dan@xxxxxxxxxxxxxxx>

[ Upstream commit 7a410953d1fb4dbe91ffcfdee9cbbf889d19b0d7 ]

The reset is a shared reset line, but reset_control_reset is still used
and reset_control_deassert is not guaranteed to have been called before
the first reset_control_assert call. When suspending the following
warning may be seen:

WARNING: CPU: 1 PID: 5530 at drivers/reset/core.c:355 reset_control_assert+0x184/0x19c
Hardware name: Hardkernel ODROID-N2 (DT)
[..]
pc : reset_control_assert+0x184/0x19c
lr : dwc3_meson_g12a_suspend+0x68/0x7c
[..]
Call trace:
reset_control_assert+0x184/0x19c
dwc3_meson_g12a_suspend+0x68/0x7c
platform_pm_suspend+0x28/0x54
__device_suspend+0x590/0xabc
dpm_suspend+0x104/0x404
dpm_suspend_start+0x84/0x1bc
suspend_devices_and_enter+0xc4/0x4fc
pm_suspend+0x198/0x2d4

Fixes: 6d9fa35a347a87 ("usb: dwc3: meson-g12a: get the reset as shared")
Signed-off-by: Dan Robertson <dan@xxxxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/usb/dwc3/dwc3-meson-g12a.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-meson-g12a.c b/drivers/usb/dwc3/dwc3-meson-g12a.c
index 1f7f4d88ed9d8..88b75b5a039c9 100644
--- a/drivers/usb/dwc3/dwc3-meson-g12a.c
+++ b/drivers/usb/dwc3/dwc3-meson-g12a.c
@@ -737,13 +737,13 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)
goto err_disable_clks;
}

- ret = reset_control_reset(priv->reset);
+ ret = reset_control_deassert(priv->reset);
if (ret)
- goto err_disable_clks;
+ goto err_assert_reset;

ret = dwc3_meson_g12a_get_phys(priv);
if (ret)
- goto err_disable_clks;
+ goto err_assert_reset;

ret = priv->drvdata->setup_regmaps(priv, base);
if (ret)
@@ -752,7 +752,7 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)
if (priv->vbus) {
ret = regulator_enable(priv->vbus);
if (ret)
- goto err_disable_clks;
+ goto err_assert_reset;
}

/* Get dr_mode */
@@ -765,13 +765,13 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)

ret = priv->drvdata->usb_init(priv);
if (ret)
- goto err_disable_clks;
+ goto err_assert_reset;

/* Init PHYs */
for (i = 0 ; i < PHY_COUNT ; ++i) {
ret = phy_init(priv->phys[i]);
if (ret)
- goto err_disable_clks;
+ goto err_assert_reset;
}

/* Set PHY Power */
@@ -809,6 +809,9 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)
for (i = 0 ; i < PHY_COUNT ; ++i)
phy_exit(priv->phys[i]);

+err_assert_reset:
+ reset_control_assert(priv->reset);
+
err_disable_clks:
clk_bulk_disable_unprepare(priv->drvdata->num_clks,
priv->drvdata->clks);
--
2.25.1