wt/lm-sensors
1
0 Fork 0
mirror of https://github.com/lm-sensors/lm-sensors.git synced 2026-11-09 16:21:51 +00:00
Code Issues Packages Projects Releases Wiki Activity

Apply tristate patch from Jesus Arias <jesus@ele.uva.es>

Browse Source 
which ensures i2c Bus is tristated correctly. It isn't clear from
      the datasheet if the 586's GPIO pins are open drain or not,
      but if they aren't, then the driver was driving the pins high
      rather than letting them get pulled high as the spec requires.
      This is corrected by toggling the direction rather than the
      data register to control the bus.


git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@1093 7894878c-1315-0410-8ee3-d5d059ff63e0
This commit is contained in:
Mark D. Studebaker committed 2001-05-26 21:23:40 +00:00
1 parent cce17dcd72
commit 7a6ba966ed
2 files changed
+15 -7
Download Patch File Download Diff File Expand all files Collapse all files

No files matched your search

kernel/busses/i2c-via.c
+14 -7
View File
@@ -63,16 +63,24 @@
static u16 pm_io_base;
/*
It does not appear from the datasheet that the GPIO pins are
open drain. So a we set a low value by setting the direction to
output and a high value by setting the direction to input and
relying on the required I2C pullup. The data value is initialized
to 0 in i2c_via_init() and never changed.
*/
static void bit_via_setscl(void *data, int state)
{
outb(state ? inb(I2C_OUT) | I2C_SCL : inb(I2C_OUT) & ~I2C_SCL,
I2C_OUT);
outb(state ? inb(I2C_DIR) & ~I2C_SCL : inb(I2C_DIR) | I2C_SCL,
I2C_DIR);
}
static void bit_via_setsda(void *data, int state)
{
outb(state ? inb(I2C_OUT) | I2C_SDA : inb(I2C_OUT) & ~I2C_SDA,
I2C_OUT);
outb(state ? inb(I2C_DIR) & ~I2C_SDA : inb(I2C_DIR) | I2C_SDA,
I2C_DIR);
}
static int bit_via_getscl(void *data)
@@ -179,15 +187,14 @@ int __init i2c_via_init(void)
return -EBUSY;
} else {
request_region(I2C_DIR, IOSPACE, IOTEXT);
outb(inb(I2C_DIR) | I2C_SDA | I2C_SCL, I2C_DIR);
outb(inb(I2C_OUT) | I2C_SDA | I2C_SCL, I2C_OUT);
outb(inb(I2C_DIR) & ~(I2C_SDA | I2C_SCL), I2C_DIR);
outb(inb(I2C_OUT) & ~(I2C_SDA | I2C_SCL), I2C_OUT);
}
if (i2c_bit_add_bus(&bit_via_ops) == 0) {
printk("i2c-via.o: Module succesfully loaded\n");
return 0;
} else {
outb(inb(I2C_DIR) & ~(I2C_SDA | I2C_SCL), I2C_DIR);
release_region(I2C_DIR, IOSPACE);
printk
("i2c-via.o: Algo-bit error, couldn't register bus\n");