Commit 1cb89a14 authored by Russell King's avatar Russell King Committed by David S. Miller
Browse files

net: sfp: re-attempt probing for phy 



Some 1000BASE-T PHY modules take a while for the PHY to wake up.
Retry the probe a number of times before deciding that the module has
no PHY.

Tested with:
 Sourcephotonics SPGBTXCNFC - PHY takes less than 50ms to respond.
 Champion One 1000SFPT - PHY takes about 200ms to respond.
 Mikrotik S-RJ01 - no PHY

Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 256e43cb

drivers/net/phy/sfp.c

+42 −17
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ enum { 
	SFP_S_FAIL,

	SFP_S_WAIT,

	SFP_S_INIT,

	SFP_S_INIT_PHY,

	SFP_S_INIT_TX_FAULT,

	SFP_S_WAIT_LOS,

	SFP_S_LINK_UP,
@@ -126,6 +127,7 @@ static const char * const sm_state_strings[] = { 
	[SFP_S_FAIL] = "fail",

	[SFP_S_WAIT] = "wait",

	[SFP_S_INIT] = "init",

	[SFP_S_INIT_PHY] = "init_phy",

	[SFP_S_INIT_TX_FAULT] = "init_tx_fault",

	[SFP_S_WAIT_LOS] = "wait_los",

	[SFP_S_LINK_UP] = "link_up",
@@ -180,6 +182,12 @@ static const enum gpiod_flags gpio_flags[] = { 
#define N_FAULT_INIT		5

#define N_FAULT			5



/* T_PHY_RETRY is the time interval between attempts to probe the PHY.

 * R_PHY_RETRY is the number of attempts.

 */

#define T_PHY_RETRY		msecs_to_jiffies(50)

#define R_PHY_RETRY		12



/* SFP module presence detection is poor: the three MOD DEF signals are

 * the same length on the PCB, which means it's possible for MOD DEF 0 to

 * connect before the I2C bus on MOD DEF 1/2.
@@ -235,6 +243,7 @@ struct sfp { 
	unsigned char sm_dev_state;

	unsigned short sm_state;

	unsigned char sm_fault_retries;

	unsigned char sm_phy_retries;



	struct sfp_eeprom_id id;

	unsigned int module_power_mW;
@@ -1416,10 +1425,8 @@ static int sfp_sm_probe_phy(struct sfp *sfp, bool is_c45) 
	int err;



	phy = get_phy_device(sfp->i2c_mii, SFP_PHY_ADDR, is_c45);

	if (phy == ERR_PTR(-ENODEV)) {

		dev_info(sfp->dev, "no PHY detected\n");

		return 0;

	}

	if (phy == ERR_PTR(-ENODEV))

		return PTR_ERR(phy);

	if (IS_ERR(phy)) {

		dev_err(sfp->dev, "mdiobus scan returned %ld\n", PTR_ERR(phy));

		return PTR_ERR(phy);
@@ -1867,6 +1874,7 @@ static void sfp_sm_module(struct sfp *sfp, unsigned int event) 
static void sfp_sm_main(struct sfp *sfp, unsigned int event)

{

	unsigned long timeout;

	int ret;



	/* Some events are global */

	if (sfp->sm_state != SFP_S_DOWN &&
@@ -1940,10 +1948,28 @@ static void sfp_sm_main(struct sfp *sfp, unsigned int event) 
			sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,

				     sfp->sm_fault_retries == N_FAULT_INIT);

		} else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {

	init_done:	/* TX_FAULT deasserted or we timed out with TX_FAULT

	init_done:

			sfp->sm_phy_retries = R_PHY_RETRY;

			goto phy_probe;

		}

		break;



	case SFP_S_INIT_PHY:

		if (event != SFP_E_TIMEOUT)

			break;

	phy_probe:

		/* TX_FAULT deasserted or we timed out with TX_FAULT

		 * clear.  Probe for the PHY and check the LOS state.

		 */

			if (sfp_sm_probe_for_phy(sfp)) {

		ret = sfp_sm_probe_for_phy(sfp);

		if (ret == -ENODEV) {

			if (--sfp->sm_phy_retries) {

				sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);

				break;

			} else {

				dev_info(sfp->dev, "no PHY detected\n");

			}

		} else if (ret) {

			sfp_sm_next(sfp, SFP_S_FAIL, 0);

			break;

		}
@@ -1955,7 +1981,6 @@ static void sfp_sm_main(struct sfp *sfp, unsigned int event) 


		/* Reset the fault retry count */

		sfp->sm_fault_retries = N_FAULT;

		}

		break;



	case SFP_S_INIT_TX_FAULT:

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