From: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
commit e46ceea3148163166ef9b7bcac578e72dd30c064 upstream.
Clocks are properly reference counted and do not need to be inside the
lock range.
Right now this triggers a false-positive lockdep warning on MT8192 based
Chromebooks, through a combination of mtk-scp that has a cros-ec-rpmsg
sub-device, the (actual) cros-ec I2C adapter registration, I2C client
(not on cros-ec) probe doing i2c transfers and enabling clocks.
This is a false positive because the cros-ec-rpmsg under mtk-scp does
not have an I2C adapter, and also each I2C adapter and cros-ec instance
have their own mutex.
Move the clk operations outside of the send_lock range.
Fixes: 63c13d61eafe ("remoteproc/mediatek: add SCP support for mt8183")
Signed-off-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20230104083110.736377-1-wenst@xxxxxxxxxxxx
[Fixed "Fixes:" tag line]
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/remoteproc/mtk_scp_ipi.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
--- a/drivers/remoteproc/mtk_scp_ipi.c
+++ b/drivers/remoteproc/mtk_scp_ipi.c
@@ -164,21 +164,21 @@ int scp_ipi_send(struct mtk_scp *scp, u3
WARN_ON(len > sizeof(send_obj->share_buf)) || WARN_ON(!buf))
return -EINVAL;
- mutex_lock(&scp->send_lock);
-
ret = clk_prepare_enable(scp->clk);
if (ret) {
dev_err(scp->dev, "failed to enable clock\n");
- goto unlock_mutex;
+ return ret;
}
+ mutex_lock(&scp->send_lock);
+
/* Wait until SCP receives the last command */
timeout = jiffies + msecs_to_jiffies(2000);
do {
if (time_after(jiffies, timeout)) {
dev_err(scp->dev, "%s: IPI timeout!\n", __func__);
ret = -ETIMEDOUT;
- goto clock_disable;
+ goto unlock_mutex;
}
} while (readl(scp->reg_base + scp->data->host_to_scp_reg));
@@ -205,10 +205,9 @@ int scp_ipi_send(struct mtk_scp *scp, u3
ret = 0;
}
-clock_disable:
- clk_disable_unprepare(scp->clk);
unlock_mutex:
mutex_unlock(&scp->send_lock);
+ clk_disable_unprepare(scp->clk);
return ret;
}
