When the i2c-parport adapter is reponsible for powering devices, it would seem reasonable to give them some time to settle before trying to access them.
Signed-off-by: Jean Delvare <[email protected]> --- drivers/i2c/busses/i2c-parport-light.c | 6 +++++- drivers/i2c/busses/i2c-parport.c | 6 +++++- 2 files changed, 10 insertions(+), 2 deletions(-) --- linux-2.6.33-rc7.orig/drivers/i2c/busses/i2c-parport-light.c 2009-06-10 05:05:27.000000000 +0200 +++ linux-2.6.33-rc7/drivers/i2c/busses/i2c-parport-light.c 2010-02-11 12:11:27.000000000 +0100 @@ -27,6 +27,7 @@ #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> @@ -127,8 +128,11 @@ static int __devinit i2c_parport_probe(s 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); --- linux-2.6.33-rc7.orig/drivers/i2c/busses/i2c-parport.c 2010-02-11 11:39:03.000000000 +0100 +++ linux-2.6.33-rc7/drivers/i2c/busses/i2c-parport.c 2010-02-11 12:03:40.000000000 +0100 @@ -27,6 +27,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> +#include <linux/delay.h> #include <linux/parport.h> #include <linux/i2c.h> #include <linux/i2c-algo-bit.h> @@ -185,8 +186,11 @@ static void i2c_parport_attach (struct p parport_setsda(port, 1); parport_setscl(port, 1); /* Other init if needed (power on...) */ - if (adapter_parm[type].init.val) + if (adapter_parm[type].init.val) { line_set(port, 1, &adapter_parm[type].init); + /* Give powered devices some time to settle */ + msleep(100); + } if (i2c_bit_add_bus(&adapter->adapter) < 0) { printk(KERN_ERR "i2c-parport: Unable to register with I2C\n"); -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
