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net: sfp: split power mode switching from probe

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Switch the power mode switching from the probe, so that we don't
repeatedly re-probe the SFP device if there is a problem accessing
the registers at I2C address 0x51.

In splitting this out, we can also fix a bug where we leave the module
in high-power mode when the upstream device is detached but the module
is still inserted.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Russell King 2019-11-10 14:07:20 +00:00 committed by David S. Miller
parent 6b0da5c9c1
commit b036a554d0
1 changed files with 65 additions and 38 deletions
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103
drivers/net/phy/sfp.c
View File

@ -49,6 +49,7 @@ enum {
SFP_MOD_EMPTY = 0,
SFP_MOD_PROBE,
SFP_MOD_HPOWER,
SFP_MOD_WAITPWR,
SFP_MOD_PRESENT,
SFP_MOD_ERROR,
@ -71,6 +72,7 @@ static const char * const mod_state_strings[] = {
[SFP_MOD_EMPTY] = "empty",
[SFP_MOD_PROBE] = "probe",
[SFP_MOD_HPOWER] = "hpower",
[SFP_MOD_WAITPWR] = "waitpwr",
[SFP_MOD_PRESENT] = "present",
[SFP_MOD_ERROR] = "error",
};
@ -1423,37 +1425,34 @@ static int sfp_module_parse_power(struct sfp *sfp)
return 0;
}
static int sfp_sm_mod_hpower(struct sfp *sfp)
static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
{
u8 val;
int err;
if (sfp->module_power_mW <= 1000)
return 0;
err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
if (err != sizeof(val)) {
dev_err(sfp->dev, "Failed to read EEPROM: %d\n", err);
err = -EAGAIN;
goto err;
return -EAGAIN;
}
val |= BIT(0);
if (enable)
val |= BIT(0);
else
val &= ~BIT(0);
err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
if (err != sizeof(val)) {
dev_err(sfp->dev, "Failed to write EEPROM: %d\n", err);
err = -EAGAIN;
goto err;
return -EAGAIN;
}
dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
sfp->module_power_mW / 1000,
(sfp->module_power_mW / 100) % 10);
return T_HPOWER_LEVEL;
if (enable)
dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
sfp->module_power_mW / 1000,
(sfp->module_power_mW / 100) % 10);
err:
return err;
return 0;
}
static int sfp_sm_mod_probe(struct sfp *sfp)
@ -1549,7 +1548,7 @@ static int sfp_sm_mod_probe(struct sfp *sfp)
if (ret < 0)
return ret;
return sfp_sm_mod_hpower(sfp);
return 0;
}
static void sfp_sm_mod_remove(struct sfp *sfp)
@ -1594,13 +1593,22 @@ static void sfp_sm_device(struct sfp *sfp, unsigned int event)
*/
static void sfp_sm_module(struct sfp *sfp, unsigned int event)
{
/* Handle remove event globally, it resets this state machine.
* Also deal with upstream detachment.
*/
if (event == SFP_E_REMOVE || sfp->sm_dev_state < SFP_DEV_DOWN) {
int err;
/* Handle remove event globally, it resets this state machine */
if (event == SFP_E_REMOVE) {
if (sfp->sm_mod_state > SFP_MOD_PROBE)
sfp_sm_mod_remove(sfp);
if (sfp->sm_mod_state != SFP_MOD_EMPTY)
sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
return;
}
/* Handle device detach globally */
if (sfp->sm_dev_state < SFP_DEV_DOWN) {
if (sfp->module_power_mW > 1000 &&
sfp->sm_mod_state > SFP_MOD_HPOWER)
sfp_sm_mod_hpower(sfp, false);
if (sfp->sm_mod_state > SFP_MOD_EMPTY)
sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
return;
}
@ -1612,26 +1620,45 @@ static void sfp_sm_module(struct sfp *sfp, unsigned int event)
break;
case SFP_MOD_PROBE:
if (event == SFP_E_TIMEOUT) {
int val = sfp_sm_mod_probe(sfp);
if (event != SFP_E_TIMEOUT)
break;
if (val == 0)
sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
else if (val > 0)
sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, val);
else if (val != -EAGAIN)
sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
else
sfp_sm_set_timer(sfp, T_PROBE_RETRY);
}
break;
case SFP_MOD_HPOWER:
if (event == SFP_E_TIMEOUT) {
sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
err = sfp_sm_mod_probe(sfp);
if (err == -EAGAIN) {
sfp_sm_set_timer(sfp, T_PROBE_RETRY);
break;
}
/* fallthrough */
if (err < 0) {
sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
break;
}
/* If this is a power level 1 module, we are done */
if (sfp->module_power_mW <= 1000)
goto insert;
sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
/* fall through */
case SFP_MOD_HPOWER:
/* Enable high power mode */
err = sfp_sm_mod_hpower(sfp, true);
if (err == 0)
sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
else if (err != -EAGAIN)
sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
else
sfp_sm_set_timer(sfp, T_PROBE_RETRY);
break;
case SFP_MOD_WAITPWR:
/* Wait for T_HPOWER_LEVEL to time out */
if (event != SFP_E_TIMEOUT)
break;
insert:
sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
break;
case SFP_MOD_PRESENT:
case SFP_MOD_ERROR:
break;