[PATCH net-next v2 11/14] dpll: dpllsim: Add support to adjust phase

[Petr Oros <poros@redhat.com>]

Add support to get and set the phase adjustment of input and output
pins. The pins advertise a granularity of 100 ps and a symmetric range
whose ends are the largest multiples of the granularity that fit a
32-bit signed value, so that the advertised ends themselves are
settable, the core validates the requested value against both and the
driver stores it. The adjustment is reset to zero every time the device
goes live, so that repeated deploy cycles start from a known state. It
becomes the baseline of the simulated phase offset measurements once
those exist.

Signed-off-by: Petr Oros <poros@redhat.com>
---
 drivers/dpll/dpllsim/dpll.c    | 40 ++++++++++++++++++++++++++++++++++
 drivers/dpll/dpllsim/dpllsim.h |  1 +
 2 files changed, 41 insertions(+)

diff --git a/drivers/dpll/dpllsim/dpll.c b/drivers/dpll/dpllsim/dpll.c
index 3caccd38a7e74a..77e7ae994bf104 100644
--- a/drivers/dpll/dpllsim/dpll.c
+++ b/drivers/dpll/dpllsim/dpll.c
@@ -12,6 +12,11 @@
 
 #include "dpllsim.h"
 
+#define DPLLSIM_PHASE_ADJUST_GRAN		100	/* ps */
+/* Largest multiple of the granularity, so the range ends are settable */
+#define DPLLSIM_PHASE_ADJUST_MAX \
+	(S32_MAX - S32_MAX % DPLLSIM_PHASE_ADJUST_GRAN)
+
 static struct dpll_pin_frequency dpllsim_freq_1pps[] = {
 	DPLL_PIN_FREQUENCY_RANGE(1, 1),
 };
@@ -159,6 +164,33 @@ static int dpllsim_pin_prio_set(const struct dpll_pin *pin, void *pin_priv,
 	return 0;
 }
 
+static int dpllsim_pin_phase_adjust_get(const struct dpll_pin *pin,
+					void *pin_priv,
+					const struct dpll_device *dpll,
+					void *dpll_priv, s32 *phase_adjust,
+					struct netlink_ext_ack *extack)
+{
+	struct dpllsim_pin *sim_pin = pin_priv;
+
+	guard(mutex)(&sim_pin->dev->lock);
+	*phase_adjust = sim_pin->phase_adjust;
+	return 0;
+}
+
+static int dpllsim_pin_phase_adjust_set(const struct dpll_pin *pin,
+					void *pin_priv,
+					const struct dpll_device *dpll,
+					void *dpll_priv,
+					const s32 phase_adjust,
+					struct netlink_ext_ack *extack)
+{
+	struct dpllsim_pin *sim_pin = pin_priv;
+
+	guard(mutex)(&sim_pin->dev->lock);
+	sim_pin->phase_adjust = phase_adjust;
+	return 0;
+}
+
 static const struct dpll_pin_ops dpllsim_input_pin_ops = {
 	.frequency_get = dpllsim_pin_frequency_get,
 	.frequency_set = dpllsim_pin_frequency_set,
@@ -167,6 +199,8 @@ static const struct dpll_pin_ops dpllsim_input_pin_ops = {
 	.state_on_dpll_set = dpllsim_pin_state_set,
 	.prio_get = dpllsim_pin_prio_get,
 	.prio_set = dpllsim_pin_prio_set,
+	.phase_adjust_get = dpllsim_pin_phase_adjust_get,
+	.phase_adjust_set = dpllsim_pin_phase_adjust_set,
 };
 
 static const struct dpll_pin_ops dpllsim_output_pin_ops = {
@@ -174,6 +208,8 @@ static const struct dpll_pin_ops dpllsim_output_pin_ops = {
 	.frequency_set = dpllsim_pin_frequency_set,
 	.direction_get = dpllsim_pin_direction_get,
 	.state_on_dpll_get = dpllsim_pin_state_get,
+	.phase_adjust_get = dpllsim_pin_phase_adjust_get,
+	.phase_adjust_set = dpllsim_pin_phase_adjust_set,
 };
 
 static const struct dpll_pin_ops *
@@ -189,6 +225,9 @@ static void dpllsim_pin_props(struct dpllsim_pin *pin,
 {
 	prop->type = pin->type;
 	prop->board_label = config_item_name(&pin->item);
+	prop->phase_range.min = -DPLLSIM_PHASE_ADJUST_MAX;
+	prop->phase_range.max = DPLLSIM_PHASE_ADJUST_MAX;
+	prop->phase_gran = DPLLSIM_PHASE_ADJUST_GRAN;
 
 	switch (pin->type) {
 	case DPLL_PIN_TYPE_GNSS:
@@ -250,6 +289,7 @@ static void dpllsim_pin_reset(struct dpllsim_pin *pin)
 {
 	pin->ops = dpllsim_pin_select_ops(pin);
 	pin->state = DPLL_PIN_STATE_DISCONNECTED;
+	pin->phase_adjust = 0;
 }
 
 /* Build sim->pins in registration order, the order the pins were created */
diff --git a/drivers/dpll/dpllsim/dpllsim.h b/drivers/dpll/dpllsim/dpllsim.h
index f59447d26a8668..886ac27f5f92d6 100644
--- a/drivers/dpll/dpllsim/dpllsim.h
+++ b/drivers/dpll/dpllsim/dpllsim.h
@@ -43,6 +43,7 @@ struct dpllsim_pin {
 
 	/* Simulated state, guarded by dev->lock */
 	enum dpll_pin_state state;
+	s32 phase_adjust;
 };
 
 struct dpllsim_dev {
-- 
2.56.0