Some SoCs e.g. (TI DRA7xx) need a START pulse to start the
RAMINIT sequence i.e. START bit must be set and cleared before
checking for the DONE bit status. Add a new DT property "raminit-pulse"
to specify if this mechanism must be used for RAMINIT.

Signed-off-by: Roger Quadros <rog...@ti.com>
---
 Documentation/devicetree/bindings/net/can/c_can.txt | 3 +++
 drivers/net/can/c_can/c_can.h                       | 1 +
 drivers/net/can/c_can/c_can_platform.c              | 8 ++++++++
 3 files changed, 12 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/can/c_can.txt 
b/Documentation/devicetree/bindings/net/can/c_can.txt
index e12d1a1..705411f 100644
--- a/Documentation/devicetree/bindings/net/can/c_can.txt
+++ b/Documentation/devicetree/bindings/net/can/c_can.txt
@@ -19,6 +19,9 @@ Optional properties:
                          register within the syscon region
 - ti,raminit-start-bit : Bit posistion of START bit in the RAMINIT register
 - ti,raminit-done-bit  : Bit position of DONE bit in the RAMINIT register
+- ti,raminit-pulse     : Property must exist if START pulse is needed for 
RAMINIT
+                         sequence i.e. START bit will be set and cleared before
+                         checking for DONE bit.
 
 Note: "ti,hwmods" field is used to fetch the base address and irq
 resources from TI, omap hwmod data base during device registration.
diff --git a/drivers/net/can/c_can/c_can.h b/drivers/net/can/c_can/c_can.h
index bf68822..85b5ad0 100644
--- a/drivers/net/can/c_can/c_can.h
+++ b/drivers/net/can/c_can/c_can.h
@@ -175,6 +175,7 @@ struct c_can_raminit {
        unsigned int reg;       /* register index within syscon */
        u8 start_bit;   /* START bit position in raminit reg. */
        u8 done_bit;    /* DONE bit position in raminit reg. */
+       bool needs_pulse;       /* If set, sets and clears START bit (pulse) */
 };
 
 /* c_can private data structure */
diff --git a/drivers/net/can/c_can/c_can_platform.c 
b/drivers/net/can/c_can/c_can_platform.c
index fb0c35b..5ae9eb3 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -120,6 +120,12 @@ static void c_can_hw_raminit_syscon(const struct 
c_can_priv *priv, bool enable)
                ctrl |= 1 << raminit->start_bit;
                regmap_write(raminit->syscon, raminit->reg, ctrl);
 
+               /* clear START bit if start pulse is needed */
+               if (raminit->needs_pulse) {
+                       ctrl &= ~(1 << raminit->start_bit);
+                       regmap_write(raminit->syscon, raminit->reg, ctrl);
+               }
+
                ctrl |= 1 << raminit->done_bit;
                c_can_hw_raminit_wait_syscon(priv, mask, ctrl);
        }
@@ -340,6 +346,8 @@ static int c_can_plat_probe(struct platform_device *pdev)
                }
 
                priv->raminit_sys.done_bit = val;
+               priv->raminit_sys.needs_pulse = of_property_read_bool(np,
+                                                                     
"ti,raminit-pulse");
                priv->raminit = c_can_hw_raminit_syscon;
                break;
        default:
-- 
1.8.3.2

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