diff --git a/drivers/net/sfc/sfe4001.c b/drivers/net/sfc/sfe4001.c
index f927281..d90fab5 100644
--- a/drivers/net/sfc/sfe4001.c
+++ b/drivers/net/sfc/sfe4001.c
@@ -13,6 +13,7 @@
  * the PHY
  */
 #include <linux/delay.h>
+#include "net_driver.h"
 #include "efx.h"
 #include "phy.h"
 #include "boards.h"
@@ -120,52 +121,15 @@
 	i2c_smbus_read_byte_data(hwmon_client, RSL);
 }
 
-static void sfe4001_fini(struct efx_nic *efx)
+static int sfe4001_poweron(struct efx_nic *efx)
 {
-	EFX_INFO(efx, "%s\n", __func__);
-
-	sfe4001_poweroff(efx);
- 	i2c_unregister_device(efx->board_info.ioexp_client);
- 	i2c_unregister_device(efx->board_info.hwmon_client);
-}
-
-/* The P0_EN_3V3X line on SFE4001 boards (from A2 onward) is connected
- * to the FLASH_CFG_1 input on the DSP.  We must keep it high at power-
- * up to allow writing the flash (done through MDIO from userland).
- */
-unsigned int sfe4001_phy_flash_cfg;
-module_param_named(phy_flash_cfg, sfe4001_phy_flash_cfg, uint, 0444);
-MODULE_PARM_DESC(phy_flash_cfg,
-		 "Force PHY to enter flash configuration mode");
-
-/* This board uses an I2C expander to provider power to the PHY, which needs to
- * be turned on before the PHY can be used.
- * Context: Process context, rtnl lock held
- */
-int sfe4001_init(struct efx_nic *efx)
-{
-	struct i2c_client *hwmon_client, *ioexp_client;
+	struct i2c_client *hwmon_client = efx->board_info.hwmon_client;
+	struct i2c_client *ioexp_client = efx->board_info.ioexp_client;
 	unsigned int i, j;
 	int rc;
 	u8 out;
 	efx_dword_t reg;
 
-	hwmon_client = i2c_new_dummy(&efx->i2c_adap, MAX6647);
-	if (!hwmon_client)
-		return -EIO;
-	efx->board_info.hwmon_client = hwmon_client;
-
-	ioexp_client = i2c_new_dummy(&efx->i2c_adap, PCA9539);
-	if (!ioexp_client) {
-		rc = -EIO;
-		goto fail_hwmon;
-	}
-	efx->board_info.ioexp_client = ioexp_client;
-
-	/* 10Xpress has fixed-function LED pins, so there is no board-specific
-	 * blink code. */
-	efx->board_info.blink = tenxpress_phy_blink;
-
 	/* Ensure that XGXS and XAUI SerDes are held in reset */
 	EFX_POPULATE_DWORD_7(reg, XX_PWRDNA_EN, 1,
 			     XX_PWRDNB_EN, 1,
@@ -177,33 +141,15 @@
 	falcon_xmac_writel(efx, &reg, XX_PWR_RST_REG_MAC);
 	udelay(10);
 
-	efx->board_info.fini = sfe4001_fini;
-
-	/* Set DSP over-temperature alert threshold */
-	EFX_INFO(efx, "DSP cut-out at %dC\n", xgphy_max_temperature);
-	rc = i2c_smbus_write_byte_data(hwmon_client, WLHO,
-				       xgphy_max_temperature);
-	if (rc)
-		goto fail_ioexp;
-
-	/* Read it back and verify */
-	rc = i2c_smbus_read_byte_data(hwmon_client, RLHN);
-	if (rc < 0)
-		goto fail_ioexp;
-	if (rc != xgphy_max_temperature) {
-		rc = -EFAULT;
-		goto fail_ioexp;
-	}
-
 	/* Clear any previous over-temperature alert */
 	rc = i2c_smbus_read_byte_data(hwmon_client, RSL);
 	if (rc < 0)
-		goto fail_ioexp;
+		return rc;
 
 	/* Enable port 0 and port 1 outputs on IO expander */
 	rc = i2c_smbus_write_byte_data(ioexp_client, P0_CONFIG, 0x00);
 	if (rc)
-		goto fail_ioexp;
+		return rc;
 	rc = i2c_smbus_write_byte_data(ioexp_client, P1_CONFIG,
 				       0xff & ~(1 << P1_SPARE_LBN));
 	if (rc)
@@ -231,7 +177,7 @@
 		out = 0xff & ~((1 << P0_EN_1V2_LBN) | (1 << P0_EN_2V5_LBN) |
 			       (1 << P0_EN_3V3X_LBN) | (1 << P0_EN_5V_LBN) |
 			       (1 << P0_X_TRST_LBN));
-		if (sfe4001_phy_flash_cfg)
+		if (efx->phy_mode & PHY_MODE_SPECIAL)
 			out |= 1 << P0_EN_3V3X_LBN;
 
 		rc = i2c_smbus_write_byte_data(ioexp_client, P0_OUT, out);
@@ -250,9 +196,9 @@
 		/* In flash config mode, DSP does not turn on AFE, so
 		 * just wait 1 second.
 		 */
-		if (sfe4001_phy_flash_cfg) {
+		if (efx->phy_mode & PHY_MODE_SPECIAL) {
 			schedule_timeout_uninterruptible(HZ);
-			goto done;
+			return 0;
 		}
 
 		for (j = 0; j < 10; ++j) {
@@ -263,23 +209,127 @@
 			if (rc < 0)
 				goto fail_on;
 			if (rc & (1 << P1_AFE_PWD_LBN))
-				goto done;
+				return 0;
 		}
 	}
 
 	EFX_INFO(efx, "timed out waiting for DSP boot\n");
 	rc = -ETIMEDOUT;
-	goto fail_on;
+fail_on:
+	sfe4001_poweroff(efx);
+	return rc;
+}
 
-done:
+/* On SFE4001 rev A2 and later, we can control the FLASH_CFG_1 pin
+ * using the 3V3X output of the IO-expander.  Allow the user to set
+ * this when the device is stopped, and keep it stopped then.
+ */
+
+static ssize_t show_phy_flash_cfg(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct efx_nic *efx = pci_get_drvdata(to_pci_dev(dev));
+	return sprintf(buf, "%d\n", !!(efx->phy_mode & PHY_MODE_SPECIAL));
+}
+
+static ssize_t set_phy_flash_cfg(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct efx_nic *efx = pci_get_drvdata(to_pci_dev(dev));
+	enum efx_phy_mode old_mode, new_mode;
+	int err;
+
+	rtnl_lock();
+	old_mode = efx->phy_mode;
+	if (count == 0 || *buf == '0')
+		new_mode = old_mode & ~PHY_MODE_SPECIAL;
+	else
+		new_mode = PHY_MODE_SPECIAL;
+	if (old_mode == new_mode) {
+		err = 0;
+	} else if (efx->state != STATE_RUNNING || netif_running(efx->net_dev)) {
+		err = -EBUSY;
+	} else {
+		efx->phy_mode = new_mode;
+		err = sfe4001_poweron(efx);
+		efx_reconfigure_port(efx);
+	}
+	rtnl_unlock();
+
+	return err ? err : count;
+}
+
+static DEVICE_ATTR(phy_flash_cfg, 0644, show_phy_flash_cfg, set_phy_flash_cfg);
+
+static void sfe4001_fini(struct efx_nic *efx)
+{
+	EFX_INFO(efx, "%s\n", __func__);
+
+	device_remove_file(&efx->pci_dev->dev, &dev_attr_phy_flash_cfg);
+	sfe4001_poweroff(efx);
+	i2c_unregister_device(efx->board_info.ioexp_client);
+	i2c_unregister_device(efx->board_info.hwmon_client);
+}
+
+/* This board uses an I2C expander to provider power to the PHY, which needs to
+ * be turned on before the PHY can be used.
+ * Context: Process context, rtnl lock held
+ */
+int sfe4001_init(struct efx_nic *efx)
+{
+	struct i2c_client *hwmon_client;
+	int rc;
+
+	hwmon_client = i2c_new_dummy(&efx->i2c_adap, MAX6647);
+	if (!hwmon_client)
+		return -EIO;
+	efx->board_info.hwmon_client = hwmon_client;
+
+	/* Set DSP over-temperature alert threshold */
+	EFX_INFO(efx, "DSP cut-out at %dC\n", xgphy_max_temperature);
+	rc = i2c_smbus_write_byte_data(hwmon_client, WLHO,
+				       xgphy_max_temperature);
+	if (rc)
+		goto fail_ioexp;
+
+	/* Read it back and verify */
+	rc = i2c_smbus_read_byte_data(hwmon_client, RLHN);
+	if (rc < 0)
+		goto fail_ioexp;
+	if (rc != xgphy_max_temperature) {
+		rc = -EFAULT;
+		goto fail_ioexp;
+	}
+
+	efx->board_info.ioexp_client = i2c_new_dummy(&efx->i2c_adap, PCA9539);
+	if (!efx->board_info.ioexp_client) {
+		rc = -EIO;
+		goto fail_hwmon;
+	}
+
+	/* 10Xpress has fixed-function LED pins, so there is no board-specific
+	 * blink code. */
+	efx->board_info.blink = tenxpress_phy_blink;
+
+	efx->board_info.fini = sfe4001_fini;
+
+	rc = sfe4001_poweron(efx);
+	if (rc)
+		goto fail_ioexp;
+
+	rc = device_create_file(&efx->pci_dev->dev, &dev_attr_phy_flash_cfg);
+	if (rc)
+		goto fail_on;
+
 	EFX_INFO(efx, "PHY is powered on\n");
 	return 0;
 
 fail_on:
 	sfe4001_poweroff(efx);
 fail_ioexp:
- 	i2c_unregister_device(ioexp_client);
+	i2c_unregister_device(efx->board_info.ioexp_client);
 fail_hwmon:
- 	i2c_unregister_device(hwmon_client);
+	i2c_unregister_device(hwmon_client);
 	return rc;
 }