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 <rogerq@xxxxxx>
---
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 0856209..2f0a6bb 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
- raminit-start-bit : Bit posistion of START bit in the RAMINIT register
- raminit-done-bit : Bit position of DONE bit in the RAMINIT register
+- 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 e7ec3b6..bc09695 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -123,6 +123,12 @@ 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);
}
@@ -343,6 +349,8 @@ 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,
+ "raminit-pulse");
priv->raminit = c_can_hw_raminit_syscon;
break;
default:
--
1.8.3.2
--
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