From 02eaf5a79100468425fae2d0baf144b6068fc4cc Mon Sep 17 00:00:00 2001 From: "Russell King (Oracle)" Date: Fri, 21 Oct 2022 16:09:43 +0100 Subject: net: sfp: check firmware provided max power Check that the firmware provided maximum power is at least 1W, which is the minimum power level for any SFP module. Now that we enforce the minimum of 1W, we can exit early from sfp_module_parse_power() if the module power is 1W or less. Signed-off-by: Russell King (Oracle) Reviewed-by: Andrew Lunn Signed-off-by: Jakub Kicinski --- drivers/net/phy/sfp.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'drivers/net/phy') diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c index 40c9a64c5e30..f7ad4d5d9041 100644 --- a/drivers/net/phy/sfp.c +++ b/drivers/net/phy/sfp.c @@ -1766,6 +1766,12 @@ static int sfp_module_parse_power(struct sfp *sfp) if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL)) power_mW = 2000; + /* Power level 1 modules (max. 1W) are always supported. */ + if (power_mW <= 1000) { + sfp->module_power_mW = power_mW; + return 0; + } + supports_a2 = sfp->id.ext.sff8472_compliance != SFP_SFF8472_COMPLIANCE_NONE || sfp->id.ext.diagmon & SFP_DIAGMON_DDM; @@ -1789,12 +1795,6 @@ static int sfp_module_parse_power(struct sfp *sfp) } } - if (power_mW <= 1000) { - /* Modules below 1W do not require a power change sequence */ - sfp->module_power_mW = power_mW; - return 0; - } - if (!supports_a2) { /* The module power level is below the host maximum and the * module appears not to implement bus address 0xa2, so assume @@ -2729,8 +2729,12 @@ static int sfp_probe(struct platform_device *pdev) device_property_read_u32(&pdev->dev, "maximum-power-milliwatt", &sfp->max_power_mW); - if (!sfp->max_power_mW) + if (sfp->max_power_mW < 1000) { + if (sfp->max_power_mW) + dev_warn(sfp->dev, + "Firmware bug: host maximum power should be at least 1W\n"); sfp->max_power_mW = 1000; + } dev_info(sfp->dev, "Host maximum power %u.%uW\n", sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10); -- cgit