[PATCH 03/13] net: can: c_can: Add support for START pulse in RAMINIT sequence
From: Roger Quadros <hidden>
Date: 2014-09-08 14:10:32
Also in:
linux-can, linux-omap
Subsystem:
can network drivers, open firmware and flattened device tree bindings, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
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 <redacted> --- 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:
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1.8.3.2