4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ben Wolsieffer <ben.wolsieffer@xxxxxxxxxxx>
[ Upstream commit 6f195d6b0da3b689922ba9e302af2f49592fa9fc ]
The STM32MP1 keeps clk_rx enabled during suspend, and therefore the
driver does not enable the clock in stm32_dwmac_init() if the device was
suspended. The problem is that this same code runs on STM32 MCUs, which
do disable clk_rx during suspend, causing the clock to never be
re-enabled on resume.
This patch adds a variant flag to indicate that clk_rx remains enabled
during suspend, and uses this to decide whether to enable the clock in
stm32_dwmac_init() if the device was suspended.
This approach fixes this specific bug with limited opportunity for
unintended side-effects, but I have a follow up patch that will refactor
the clock configuration and hopefully make it less error prone.
Fixes: 6528e02cc9ff ("net: ethernet: stmmac: add adaptation for stm32mp157c.")
Signed-off-by: Ben Wolsieffer <ben.wolsieffer@xxxxxxxxxxx>
Reviewed-by: Jacob Keller <jacob.e.keller@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230927175749.1419774-1-ben.wolsieffer@xxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
index 7e2e79dedebf2..df7fc6b675a53 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
@@ -57,6 +57,7 @@ struct stm32_ops {
int (*parse_data)(struct stm32_dwmac *dwmac,
struct device *dev);
u32 syscfg_eth_mask;
+ bool clk_rx_enable_in_suspend;
};
static int stm32_dwmac_init(struct plat_stmmacenet_data *plat_dat)
@@ -74,7 +75,8 @@ static int stm32_dwmac_init(struct plat_stmmacenet_data *plat_dat)
if (ret)
return ret;
- if (!dwmac->dev->power.is_suspended) {
+ if (!dwmac->ops->clk_rx_enable_in_suspend ||
+ !dwmac->dev->power.is_suspended) {
ret = clk_prepare_enable(dwmac->clk_rx);
if (ret) {
clk_disable_unprepare(dwmac->clk_tx);
@@ -413,7 +415,8 @@ static struct stm32_ops stm32mp1_dwmac_data = {
.suspend = stm32mp1_suspend,
.resume = stm32mp1_resume,
.parse_data = stm32mp1_parse_data,
- .syscfg_eth_mask = SYSCFG_MP1_ETH_MASK
+ .syscfg_eth_mask = SYSCFG_MP1_ETH_MASK,
+ .clk_rx_enable_in_suspend = true
};
static const struct of_device_id stm32_dwmac_match[] = {
--
2.40.1
