[PATCH iwl-next v1 2/4] ice: dpll: Use switch statements to handle pin states

[Sergey Temerkhanov <sergey.temerkhanov@intel.com>]

Use switch statements to handle pin states to make the code more
readable. This also makes this code more future-proof, should any
new states appear.

This also changes how direction-mismatched state requests are handled in
ice_dpll_sma_pin_state_set(). Previously, requesting CONNECTED on an
INPUT-direction SMA pin or SELECTABLE on an OUTPUT-direction pin would
fall through to ice_dpll_pin_disable() and return success. After this
change those requests return -EINVAL without issuing a firmware command.
Because the DPLL netlink core does not filter pin states by direction
before calling the driver, this is a user-visible netlink API change.

Signed-off-by: Sergey Temerkhanov <sergey.temerkhanov@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Przemyslaw Korba <przemyslaw.korba@intel.com>
---
 drivers/net/ethernet/intel/ice/ice_dpll.c | 65 ++++++++++++++++++-----
 1 file changed, 53 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_dpll.c b/drivers/net/ethernet/intel/ice/ice_dpll.c
index fed7c9fea953..54958e17713b 100644
--- a/drivers/net/ethernet/intel/ice/ice_dpll.c
+++ b/drivers/net/ethernet/intel/ice/ice_dpll.c
@@ -1320,10 +1320,12 @@ ice_dpll_ufl_pin_state_set(const struct dpll_pin *pin, void *pin_priv,
 	ret = -EINVAL;
 	switch (p->idx) {
 	case ICE_DPLL_PIN_SW_1_IDX:
-		if (state == DPLL_PIN_STATE_CONNECTED) {
+		switch (state) {
+		case DPLL_PIN_STATE_CONNECTED:
 			data &= ~ICE_SMA1_MASK;
 			enable = true;
-		} else if (state == DPLL_PIN_STATE_DISCONNECTED) {
+			break;
+		case DPLL_PIN_STATE_DISCONNECTED:
 			/* Skip if U.FL1 is not active, setting TX_EN
 			 * while DIR_EN is set would also deactivate
 			 * the paired SMA1 output.
@@ -1334,18 +1336,21 @@ ice_dpll_ufl_pin_state_set(const struct dpll_pin *pin, void *pin_priv,
 			}
 			data |= ICE_SMA1_TX_EN;
 			enable = false;
-		} else {
+			break;
+		default:
 			goto unlock;
 		}
 		target = p->output;
 		type = ICE_DPLL_PIN_TYPE_OUTPUT;
 		break;
 	case ICE_DPLL_PIN_SW_2_IDX:
-		if (state == DPLL_PIN_STATE_SELECTABLE) {
+		switch (state) {
+		case DPLL_PIN_STATE_SELECTABLE:
 			data |= ICE_SMA2_DIR_EN;
 			data &= ~ICE_SMA2_UFL2_RX_DIS;
 			enable = true;
-		} else if (state == DPLL_PIN_STATE_DISCONNECTED) {
+			break;
+		case DPLL_PIN_STATE_DISCONNECTED:
 			/* Skip if U.FL2 is not active, setting
 			 * UFL2_RX_DIS could also disable the paired
 			 * SMA2 input.
@@ -1357,7 +1362,8 @@ ice_dpll_ufl_pin_state_set(const struct dpll_pin *pin, void *pin_priv,
 			}
 			data |= ICE_SMA2_UFL2_RX_DIS;
 			enable = false;
-		} else {
+			break;
+		default:
 			goto unlock;
 		}
 		target = p->input;
@@ -1484,14 +1490,43 @@ ice_dpll_sma_pin_state_set(const struct dpll_pin *pin, void *pin_priv,
 		if (ret)
 			goto unlock;
 	}
-	if (sma->direction == DPLL_PIN_DIRECTION_INPUT) {
-		enable = state == DPLL_PIN_STATE_SELECTABLE;
+	switch (state) {
+	case DPLL_PIN_STATE_SELECTABLE:
+		if (sma->direction == DPLL_PIN_DIRECTION_OUTPUT) {
+			enable = false;
+			ret = -EINVAL;
+			goto unlock;
+		}
+		enable = true;
+		break;
+	case DPLL_PIN_STATE_CONNECTED:
+		if (sma->direction == DPLL_PIN_DIRECTION_INPUT) {
+			enable = false;
+			ret = -EINVAL;
+			goto unlock;
+		}
+		enable = true;
+		break;
+	case DPLL_PIN_STATE_DISCONNECTED:
+		enable = false;
+		break;
+	default:
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	switch (sma->direction) {
+	case DPLL_PIN_DIRECTION_INPUT:
 		target = sma->input;
 		type = ICE_DPLL_PIN_TYPE_INPUT;
-	} else {
-		enable = state == DPLL_PIN_STATE_CONNECTED;
+		break;
+	case DPLL_PIN_DIRECTION_OUTPUT:
 		target = sma->output;
 		type = ICE_DPLL_PIN_TYPE_OUTPUT;
+		break;
+	default:
+		ret = -EINVAL;
+		goto unlock;
 	}
 
 	if (enable)
@@ -4631,7 +4666,8 @@ static int ice_dpll_init_info_sw_pins(struct ice_pf *pf)
 		pin->prop.capabilities = caps;
 		pin->pf = pf;
 		pin->prop.board_label = ice_dpll_sw_pin_ufl[i];
-		if (i == ICE_DPLL_PIN_SW_1_IDX) {
+		switch (i) {
+		case ICE_DPLL_PIN_SW_1_IDX:
 			pin->direction = DPLL_PIN_DIRECTION_OUTPUT;
 			pin_abs_idx = ICE_DPLL_PIN_SW_OUTPUT_ABS(i);
 			pin->prop.freq_supported =
@@ -4641,7 +4677,8 @@ static int ice_dpll_init_info_sw_pins(struct ice_pf *pf)
 			pin->prop.freq_supported_num = freq_supp_num;
 			pin->input = NULL;
 			pin->output = &d->outputs[pin_abs_idx];
-		} else if (i == ICE_DPLL_PIN_SW_2_IDX) {
+			break;
+		case ICE_DPLL_PIN_SW_2_IDX:
 			pin->direction = DPLL_PIN_DIRECTION_INPUT;
 			pin_abs_idx = ICE_DPLL_PIN_SW_INPUT_ABS(i) +
 				      input_idx_offset;
@@ -4654,6 +4691,10 @@ static int ice_dpll_init_info_sw_pins(struct ice_pf *pf)
 			pin->prop.capabilities =
 				(DPLL_PIN_CAPABILITIES_PRIORITY_CAN_CHANGE |
 				 caps);
+			break;
+		default:
+			dev_err(ice_pf_to_dev(pf), "Invalid U.FL pin index: %d\n", i);
+			return -EINVAL;
 		}
 		pin->muxed = &d->sma[i];
 		ice_dpll_phase_range_set(&pin->prop.phase_range, phase_adj_max);
-- 
2.53.0