4.19-stable review patch. If anyone has any objections, please let me know.
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From: Ben Wolsieffer ben.wolsieffer@hefring.com
[ 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@hefring.com Reviewed-by: Jacob Keller jacob.e.keller@intel.com Link: https://lore.kernel.org/r/20230927175749.1419774-1-ben.wolsieffer@hefring.co... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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[] = {