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Add OLPC AP-SP input driver

PATCH In review Daniel Drake 2 participants 4 messages Jun 28, 2013

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Daniel Drake

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#0 lore raw

PATCH v3 1/1 Add OLPC AP-SP input driver

The OLPC XO-1.75 and XO-4 laptops include a PS/2 touchpad and an AT keyboard, yet they do not have a hardware PS/2 controller. Instead, a firmware runs on a dedicated core ("Security Processor", part of the SoC) that acts as a PS/2 controller through bit-banging.

Communication between the main cpu (Application Processor) and the Security Processor happens via a standard command mechanism implemented by the SoC. Add a driver for this interface to enable keyboard/mouse input on this platform.

Original author: Saadia Baloch

Signed-off-by Daniel Drake <[email protected]>
---
 .../devicetree/bindings/serio/olpc,ap-sp.txt       |  13 +
 drivers/input/serio/Kconfig                        |  10 +
 drivers/input/serio/Makefile                       |   1 +
 drivers/input/serio/olpc_apsp.c                    | 280 +++++++++++++++++++++
 4 files changed, 304 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/serio/olpc,ap-sp.txt
 create mode 100644 drivers/input/serio/olpc_apsp.c

v2: Use dev_dbg(). Disable interrupts during unload, and remove bad use of devm.

v3: Avoid sleep in write function. Reference count open/close operations as both ports share the same interrupt. Fix devm_ioremap_resource() error handling. Use SERIO_8042 type. Only register IRQ handler after port structure is ready.

Documentation/devicetree/bindings/serio/olpc,ap-sp.txt new file +13 -0
new file mode 100644
index 0000000..0e72183
@@ -0,0 +1,13 @@
+OLPC AP-SP serio interface
+
+Required properties:
+- compatible : "olpc,ap-sp"
+- reg : base address and length of SoC's WTM registers
+- interrupts : SP-AP interrupt
+
+Example:
+	ap-sp@d4290000 {
+		compatible = "olpc,ap-sp";
+		reg = <0xd4290000 0x1000>;
+		interrupts = <40>;
+	}
drivers/input/serio/Kconfig +10 -0
index 1bda828..94c17c2 100644
@@ -256,4 +256,14 @@ config SERIO_APBPS2
 	  To compile this driver as a module, choose M here: the module will
 	  be called apbps2.
 
+config SERIO_OLPC_APSP
+	tristate "OLPC AP-SP input support"
+	depends on OF
+	help
+	  Say Y here if you want support for the keyboard and touchpad included
+	  in the OLPC XO-1.75 and XO-4 laptops.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called olpc_apsp.
+
 endif
drivers/input/serio/Makefile +1 -0
index 8edb36c..12298b1 100644
@@ -27,3 +27,4 @@ obj-$(CONFIG_SERIO_XILINX_XPS_PS2)	+= xilinx_ps2.o
 obj-$(CONFIG_SERIO_ALTERA_PS2)	+= altera_ps2.o
 obj-$(CONFIG_SERIO_ARC_PS2)	+= arc_ps2.o
 obj-$(CONFIG_SERIO_APBPS2)	+= apbps2.o
+obj-$(CONFIG_SERIO_OLPC_APSP)	+= olpc_apsp.o
drivers/input/serio/olpc_apsp.c new file +280 -0

280 lines not on this page · raw message

Signature · 1 line
1.8.1.4
maintainer
#1 lore raw

Hi Daniel,

Quoted 10 lines · Daniel Drake
drivers/input/serio/olpc_apsp.c new file +10 -0
+static int olpc_apsp_open(struct serio *port)
+{
+	struct olpc_apsp *priv = port->port_data;
+	unsigned int tmp;
+
+	if (priv->open_count++ == 0) {
+		/* Enable interrupt 0 by clearing its bit */
+		tmp = readl(priv->base + PJ_INTERRUPT_MASK);
+		writel(tmp & ~INT_0, priv->base + PJ_INTERRUPT_MASK);
+	}

drivers/input/serio/olpc_apsp.c line 161

Quoted 10 lines
drivers/input/serio/olpc_apsp.c new file +10 -0
+
+	return 0;
+}
+
+static void olpc_apsp_close(struct serio *port)
+{
+	struct olpc_apsp *priv = port->port_data;
+	unsigned int tmp;
+
+	if (--priv->open_count == 0) {

Both need locking. It looks like you need the song and dance similar to what i8042 has to do with it's multiplexed ports. Or ps2mult.c...

Signature · 1 line
Dmitry
author
#2 lore raw
Quoted 9 lines · Dmitry Torokhov

drivers/input/serio/olpc_apsp.c line 161

Quoted 6 lines
drivers/input/serio/olpc_apsp.c new file +6 -0
+static void olpc_apsp_close(struct serio *port)
+{
+     struct olpc_apsp *priv = port->port_data;
+     unsigned int tmp;
+
+     if (--priv->open_count == 0) {

Both need locking. It looks like you need the song and dance similar to what i8042 has to do with it's multiplexed ports. Or ps2mult.c...

I thought they would both be locked already, due to this comment in serio.c:

/* called from serio_driver->connect/disconnect methods under serio_mutex */

Or am I missing something there?

Thanks
Daniel

maintainer
#3 lore raw
Quoted 12 lines · Daniel Drake
Quoted 9 lines · Dmitry Torokhov

drivers/input/serio/olpc_apsp.c line 161

Quoted 6 lines
drivers/input/serio/olpc_apsp.c new file +6 -0
+static void olpc_apsp_close(struct serio *port)
+{
+     struct olpc_apsp *priv = port->port_data;
+     unsigned int tmp;
+
+     if (--priv->open_count == 0) {

Both need locking. It looks like you need the song and dance similar to what i8042 has to do with it's multiplexed ports. Or ps2mult.c...

Quoted 5 lines

I thought they would both be locked already, due to this comment in serio.c:

/* called from serio_driver->connect/disconnect methods under serio_mutex */

Or am I missing something there?

Hmm, you are right... I'll add a comment there to remind myself.

Signature · 1 line
Dmitry