[net: ethernet: stmmac: some fixes and optimizations 1/5] net: ethernet: stmmac: Add support for syscfg clock

From: Christophe Roullier
Date: Tue Oct 29 2019 - 06:15:19 EST


Add optional support for syscfg clock in dwmac-stm32.c
Now Syscfg clock is activated automatically when syscfg
registers are used

Signed-off-by: Christophe Roullier <christophe.roullier@xxxxxx>
---
.../net/ethernet/stmicro/stmmac/dwmac-stm32.c | 36 +++++++++++++------
1 file changed, 25 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
index 4ef041bdf6a1..7e6619868cc1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
@@ -152,23 +152,32 @@ static int stm32mp1_clk_prepare(struct stm32_dwmac *dwmac, bool prepare)
int ret = 0;

if (prepare) {
- ret = clk_prepare_enable(dwmac->syscfg_clk);
- if (ret)
- return ret;
-
+ if (dwmac->syscfg_clk) {
+ ret = clk_prepare_enable(dwmac->syscfg_clk);
+ if (ret)
+ return ret;
+ }
if (dwmac->clk_eth_ck) {
ret = clk_prepare_enable(dwmac->clk_eth_ck);
if (ret) {
- clk_disable_unprepare(dwmac->syscfg_clk);
+ if (dwmac->syscfg_clk)
+ goto unprepare_syscfg;
return ret;
}
}
} else {
- clk_disable_unprepare(dwmac->syscfg_clk);
+ if (dwmac->syscfg_clk)
+ clk_disable_unprepare(dwmac->syscfg_clk);
+
if (dwmac->clk_eth_ck)
clk_disable_unprepare(dwmac->clk_eth_ck);
}
return ret;
+
+unprepare_syscfg:
+ clk_disable_unprepare(dwmac->syscfg_clk);
+
+ return ret;
}

static int stm32mp1_set_mode(struct plat_stmmacenet_data *plat_dat)
@@ -296,7 +305,7 @@ static int stm32mp1_parse_data(struct stm32_dwmac *dwmac,
{
struct platform_device *pdev = to_platform_device(dev);
struct device_node *np = dev->of_node;
- int err = 0;
+ int err;

/* Gigabit Ethernet 125MHz clock selection. */
dwmac->eth_clk_sel_reg = of_property_read_bool(np, "st,eth-clk-sel");
@@ -320,13 +329,17 @@ static int stm32mp1_parse_data(struct stm32_dwmac *dwmac,
return PTR_ERR(dwmac->clk_ethstp);
}

- /* Clock for sysconfig */
+ /* Optional Clock for sysconfig */
dwmac->syscfg_clk = devm_clk_get(dev, "syscfg-clk");
if (IS_ERR(dwmac->syscfg_clk)) {
- dev_err(dev, "No syscfg clock provided...\n");
- return PTR_ERR(dwmac->syscfg_clk);
+ err = PTR_ERR(dwmac->syscfg_clk);
+ if (err != -ENOENT)
+ return err;
+ dwmac->syscfg_clk = NULL;
}

+ err = 0;
+
/* Get IRQ information early to have an ability to ask for deferred
* probe if needed before we went too far with resource allocation.
*/
@@ -436,7 +449,8 @@ static int stm32mp1_suspend(struct stm32_dwmac *dwmac)
return ret;

clk_disable_unprepare(dwmac->clk_tx);
- clk_disable_unprepare(dwmac->syscfg_clk);
+ if (dwmac->syscfg_clk)
+ clk_disable_unprepare(dwmac->syscfg_clk);
if (dwmac->clk_eth_ck)
clk_disable_unprepare(dwmac->clk_eth_ck);

--
2.17.1