net: stmmac: Add support for optional reset control
The DWMAC has a reset assert line, which is used on some SoCs. Add an
optional reset control to stmmac driver core.
To support reset control deferred probing, this patch changes the driver
probe function to return the actual error, instead of just -EINVAL.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 6e52c0f..b59d1ef 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -5,6 +5,7 @@
select PHYLIB
select CRC32
select PTP_1588_CLOCK
+ select RESET_CONTROLLER
---help---
This is the driver for the Ethernet IPs are built around a
Synopsys IP Core and only tested on the STMicroelectronics
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 73709e9..c1c141f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -32,6 +32,7 @@
#include <linux/pci.h>
#include "common.h"
#include <linux/ptp_clock_kernel.h>
+#include <linux/reset.h>
struct stmmac_priv {
/* Frequently used values are kept adjacent for cache effect */
@@ -91,6 +92,7 @@
int wolopts;
int wol_irq;
struct clk *stmmac_clk;
+ struct reset_control *stmmac_rst;
int clk_csr;
struct timer_list eee_ctrl_timer;
int lpi_irq;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 0d2c4cb..0c5c120 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -51,6 +51,7 @@
#include <linux/net_tstamp.h>
#include "stmmac_ptp.h"
#include "stmmac.h"
+#include <linux/reset.h>
#define STMMAC_ALIGN(x) L1_CACHE_ALIGN(x)
#define JUMBO_LEN 9000
@@ -2728,10 +2729,24 @@
if (IS_ERR(priv->stmmac_clk)) {
dev_warn(priv->device, "%s: warning: cannot get CSR clock\n",
__func__);
+ ret = PTR_ERR(priv->stmmac_clk);
goto error_clk_get;
}
clk_prepare_enable(priv->stmmac_clk);
+ priv->stmmac_rst = devm_reset_control_get(priv->device,
+ STMMAC_RESOURCE_NAME);
+ if (IS_ERR(priv->stmmac_rst)) {
+ if (PTR_ERR(priv->stmmac_rst) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto error_hw_init;
+ }
+ dev_info(priv->device, "no reset control found\n");
+ priv->stmmac_rst = NULL;
+ }
+ if (priv->stmmac_rst)
+ reset_control_deassert(priv->stmmac_rst);
+
/* Init MAC and get the capabilities */
ret = stmmac_hw_init(priv);
if (ret)
@@ -2808,7 +2823,7 @@
error_clk_get:
free_netdev(ndev);
- return NULL;
+ return ERR_PTR(ret);
}
/**
@@ -2832,6 +2847,8 @@
stmmac_mdio_unregister(ndev);
netif_carrier_off(ndev);
unregister_netdev(ndev);
+ if (priv->stmmac_rst)
+ reset_control_assert(priv->stmmac_rst);
clk_disable_unprepare(priv->stmmac_clk);
free_netdev(ndev);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
index 37ba2e0..2916089 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
@@ -100,9 +100,9 @@
stmmac_default_data();
priv = stmmac_dvr_probe(&(pdev->dev), &plat_dat, addr);
- if (!priv) {
+ if (IS_ERR(priv)) {
pr_err("%s: main driver probe failed", __func__);
- ret = -ENODEV;
+ ret = PTR_ERR(priv);
goto err_out;
}
priv->dev->irq = pdev->irq;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 6d0bf22..cc6b89a7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -152,9 +152,9 @@
}
priv = stmmac_dvr_probe(&(pdev->dev), plat_dat, addr);
- if (!priv) {
+ if (IS_ERR(priv)) {
pr_err("%s: main driver probe failed", __func__);
- return -ENODEV;
+ return PTR_ERR(priv);
}
/* Get MAC address if available (DT) */