Hotplug platform data is common across the various systems, while hotplug driver should be able to configure only the instances relevant to specific system. For example, platform hoptplug data might contain descriptions for fan1, fan2, ..., fan{n}, while some systems equipped with all 'n' fans, others with less. Same for power units, power controllers, ASICs and so on. For detection of the real number of equipped devices capability registers are used. These registers used to indicate presence of hotplug devices through the bitmap. For some new big modular systems, these registers will provide presence by counters. Use slot parameter to determine whether capability register contains bitmask or counter. Some 'capability' registers can be shared between different resources. Use fields 'capability_bit' and 'capability_mask' for getting only relevant capability bits. Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxx> Reviewed-by: Felix Radensky <fradensky@xxxxxxxxxx> --- drivers/platform/mellanox/mlxreg-hotplug.c | 23 ++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/platform/mellanox/mlxreg-hotplug.c b/drivers/platform/mellanox/mlxreg-hotplug.c index 6aa2a4650367..613485c8d22b 100644 --- a/drivers/platform/mellanox/mlxreg-hotplug.c +++ b/drivers/platform/mellanox/mlxreg-hotplug.c @@ -274,6 +274,13 @@ static int mlxreg_hotplug_attr_init(struct mlxreg_hotplug_priv_data *priv) if (ret) return ret; + if (!regval) + continue; + + /* Remove non-relevant bits. */ + if (item->capability_mask) + regval = rol32(regval & item->capability_mask, + item->capability_bit); item->mask = GENMASK((regval & item->mask) - 1, 0); } @@ -294,7 +301,19 @@ static int mlxreg_hotplug_attr_init(struct mlxreg_hotplug_priv_data *priv) if (ret) return ret; - if (!(regval & data->bit)) { + /* + * In case slot field is provided, capability + * register contains counter, otherwise bitmask. + * Skip non-relevant entries if slot set and + * exceeds counter. Othewise validate entry by + * matching bitmask. + */ + if (data->capability_mask) + regval = rol32(regval & data->capability_mask, + data->capability_bit); + if (data->slot > regval) { + break; + } else if (!(regval & data->bit) && !data->slot) { data++; continue; } @@ -611,7 +630,7 @@ static int mlxreg_hotplug_set_irq(struct mlxreg_hotplug_priv_data *priv) if (ret) goto out; - if (!(regval & data->bit)) + if (!(regval & data->bit) && !data->slot) item->mask &= ~BIT(j); } } -- 2.44.0