viafb: fix I2C emulation on GPIO ports

This patch fixes the I2C emulation on GPIO ports by enabling it
(software controlled) and disabling the output on a GPIO line before
reading it.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
This commit is contained in:
Florian Tobias Schandinat 2011-12-29 23:37:07 +00:00
parent e75892715d
commit 2c4c8a8a73

View file

@ -51,7 +51,7 @@ static void via_i2c_setscl(void *data, int state)
val |= 0x01;
break;
case VIA_PORT_GPIO:
val |= 0x80;
val |= 0x82;
break;
default:
printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");
@ -67,6 +67,9 @@ static int via_i2c_getscl(void *data)
int ret = 0;
spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
if (adap_data->type == VIA_PORT_GPIO)
via_write_reg_mask(adap_data->io_port, adap_data->ioport_index,
0, 0x80);
if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x08)
ret = 1;
spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
@ -80,6 +83,9 @@ static int via_i2c_getsda(void *data)
int ret = 0;
spin_lock_irqsave(&i2c_vdev->reg_lock, flags);
if (adap_data->type == VIA_PORT_GPIO)
via_write_reg_mask(adap_data->io_port, adap_data->ioport_index,
0, 0x40);
if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x04)
ret = 1;
spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);
@ -103,7 +109,7 @@ static void via_i2c_setsda(void *data, int state)
val |= 0x01;
break;
case VIA_PORT_GPIO:
val |= 0x40;
val |= 0x42;
break;
default:
printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");