clk: bcm281xx: add clock hysteresis support

Add support for clock gate hysteresis control.  For now, if it's
defined for a clock, it's enabled.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/clk/bcm/clk-kona-setup.c b/drivers/clk/bcm/clk-kona-setup.c
index 773ad7c7dd59..e5aededdd322 100644
--- a/drivers/clk/bcm/clk-kona-setup.c
+++ b/drivers/clk/bcm/clk-kona-setup.c
@@ -81,6 +81,7 @@ static bool peri_clk_data_offsets_valid(struct kona_clk *bcm_clk)
         struct peri_clk_data *peri;
         struct bcm_clk_policy *policy;
         struct bcm_clk_gate *gate;
+        struct bcm_clk_hyst *hyst;
         struct bcm_clk_div *div;
         struct bcm_clk_sel *sel;
         struct bcm_clk_trig *trig;
@@ -106,12 +107,25 @@ static bool peri_clk_data_offsets_valid(struct kona_clk *bcm_clk)
         }
 
         gate = &peri->gate;
+        hyst = &peri->hyst;
         if (gate_exists(gate)) {
                 if (gate->offset > limit) {
                         pr_err("%s: bad gate offset for %s (%u > %u)\n",
                                 __func__, name, gate->offset, limit);
                         return false;
                 }
+
+                if (hyst_exists(hyst)) {
+                        if (hyst->offset > limit) {
+                                pr_err("%s: bad hysteresis offset for %s "
+                                        "(%u > %u)\n", __func__,
+                                        name, hyst->offset, limit);
+                                return false;
+                        }
+                }
+        } else if (hyst_exists(hyst)) {
+                pr_err("%s: hysteresis but no gate for %s\n", __func__, name);
+                return false;
         }
 
         div = &peri->div;
@@ -261,6 +275,17 @@ static bool gate_valid(struct bcm_clk_gate *gate, const char *field_name,
         return true;
 }
 
+static bool hyst_valid(struct bcm_clk_hyst *hyst, const char *clock_name)
+{
+        if (!bit_posn_valid(hyst->en_bit, "hysteresis enable", clock_name))
+                return false;
+
+        if (!bit_posn_valid(hyst->val_bit, "hysteresis value", clock_name))
+                return false;
+
+        return true;
+}
+
 /*
  * A selector bitfield must be valid.  Its parent_sel array must
  * also be reasonable for the field.
@@ -379,6 +404,7 @@ peri_clk_data_valid(struct kona_clk *bcm_clk)
         struct peri_clk_data *peri;
         struct bcm_clk_policy *policy;
         struct bcm_clk_gate *gate;
+        struct bcm_clk_hyst *hyst;
         struct bcm_clk_sel *sel;
         struct bcm_clk_div *div;
         struct bcm_clk_div *pre_div;
@@ -406,6 +432,10 @@ peri_clk_data_valid(struct kona_clk *bcm_clk)
         if (gate_exists(gate) && !gate_valid(gate, "gate", name))
                 return false;
 
+        hyst = &peri->hyst;
+        if (hyst_exists(hyst) && !hyst_valid(hyst, name))
+                return false;
+
         sel = &peri->sel;
         if (selector_exists(sel)) {
                 if (!sel_valid(sel, "selector", name))