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>
This commit is contained in:
Jean Delvare 2010-03-02 12:23:45 +01:00
parent 3585925448
commit 927ab2f807
3 changed files with 51 additions and 3 deletions

View File

@ -9,3 +9,14 @@ parport handling is not an option. The drawback is a reduced portability
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.

View File

@ -605,6 +605,7 @@ config I2C_PARPORT
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.

View File

@ -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 @@ static u16 base;
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 @@ static struct i2c_adapter parport_adapter = {
.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 @@ static int __devinit i2c_parport_probe(struct platform_device *pdev)
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;
}
/* 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 @@ static int __init i2c_parport_init(void)
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;