diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-parport-light.c')
-rw-r--r-- | drivers/i2c/busses/i2c-parport-light.c | 48 |
1 files changed, 44 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-parport-light.c b/drivers/i2c/busses/i2c-parport-light.c index 322c5691e38..5f41ec0f72d 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 @@ -27,10 +27,12 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> +#include <linux/delay.h> #include <linux/platform_device.h> #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" @@ -43,6 +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) @@ -119,6 +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; @@ -127,18 +143,39 @@ static int __devinit i2c_parport_probe(struct platform_device *pdev) parport_setsda(NULL, 1); parport_setscl(NULL, 1); /* Other init if needed (power on...) */ - if (adapter_parm[type].init.val) + if (adapter_parm[type].init.val) { line_set(1, &adapter_parm[type].init); + /* Give powered devices some time to settle */ + msleep(100); + } 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...) */ @@ -205,6 +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; |