i2c-parport-light: Add SMBus alert support
Add support for the SMBus alert mechanism to the i2c-parport-light
driver. The ADM1032 evaluation board at least is properly wired for
this.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
diff --git a/Documentation/i2c/busses/i2c-parport-light b/Documentation/i2c/busses/i2c-parport-light
index 2874364..bdc9cbb 100644
--- a/Documentation/i2c/busses/i2c-parport-light
+++ b/Documentation/i2c/busses/i2c-parport-light
@@ -9,3 +9,14 @@
and the impossibility to daisy-chain other parallel port devices.
Please see i2c-parport for documentation.
+
+Module parameters:
+
+* type: type of adapter (see i2c-parport or modinfo)
+
+* base: base I/O address
+ Default is 0x378 which is fairly common for parallel ports, at least on PC.
+
+* irq: optional IRQ
+ This must be passed if you want SMBus alert support, assuming your adapter
+ actually supports this.
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 4d65546..4cc3807 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -605,6 +605,7 @@
config I2C_PARPORT_LIGHT
tristate "Parallel port adapter (light)"
select I2C_ALGOBIT
+ select I2C_SMBUS
help
This supports parallel port I2C adapters such as the ones made by
Philips or Velleman, Analog Devices evaluation boards, and more.
diff --git a/drivers/i2c/busses/i2c-parport-light.c b/drivers/i2c/busses/i2c-parport-light.c
index 5383f64..5f41ec0 100644
--- a/drivers/i2c/busses/i2c-parport-light.c
+++ b/drivers/i2c/busses/i2c-parport-light.c
@@ -1,7 +1,7 @@
/* ------------------------------------------------------------------------ *
* i2c-parport-light.c I2C bus over parallel port *
* ------------------------------------------------------------------------ *
- Copyright (C) 2003-2007 Jean Delvare <khali@linux-fr.org>
+ Copyright (C) 2003-2010 Jean Delvare <khali@linux-fr.org>
Based on older i2c-velleman.c driver
Copyright (C) 1995-2000 Simon G. Vogl
@@ -32,6 +32,7 @@
#include <linux/ioport.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
+#include <linux/i2c-smbus.h>
#include <asm/io.h>
#include "i2c-parport.h"
@@ -44,6 +45,10 @@
module_param(base, ushort, 0);
MODULE_PARM_DESC(base, "Base I/O address");
+static int irq;
+module_param(irq, int, 0);
+MODULE_PARM_DESC(irq, "IRQ (optional)");
+
/* ----- Low-level parallel port access ----------------------------------- */
static inline void port_write(unsigned char p, unsigned char d)
@@ -120,6 +125,16 @@
.name = "Parallel port adapter (light)",
};
+/* SMBus alert support */
+static struct i2c_smbus_alert_setup alert_data = {
+ .alert_edge_triggered = 1,
+};
+static struct i2c_client *ara;
+static struct lineop parport_ctrl_irq = {
+ .val = (1 << 4),
+ .port = CTRL,
+};
+
static int __devinit i2c_parport_probe(struct platform_device *pdev)
{
int err;
@@ -136,13 +151,31 @@
parport_adapter.dev.parent = &pdev->dev;
err = i2c_bit_add_bus(&parport_adapter);
- if (err)
+ if (err) {
dev_err(&pdev->dev, "Unable to register with I2C\n");
- return err;
+ return err;
+ }
+
+ /* Setup SMBus alert if supported */
+ if (adapter_parm[type].smbus_alert && irq) {
+ alert_data.irq = irq;
+ ara = i2c_setup_smbus_alert(&parport_adapter, &alert_data);
+ if (ara)
+ line_set(1, &parport_ctrl_irq);
+ else
+ dev_warn(&pdev->dev, "Failed to register ARA client\n");
+ }
+
+ return 0;
}
static int __devexit i2c_parport_remove(struct platform_device *pdev)
{
+ if (ara) {
+ line_set(0, &parport_ctrl_irq);
+ i2c_unregister_device(ara);
+ ara = NULL;
+ }
i2c_del_adapter(&parport_adapter);
/* Un-init if needed (power off...) */
@@ -209,6 +242,9 @@
if (!request_region(base, 3, DRVNAME))
return -EBUSY;
+ if (irq != 0)
+ pr_info(DRVNAME ": using irq %d\n", irq);
+
if (!adapter_parm[type].getscl.val)
parport_algo_data.getscl = NULL;