From 96c19bd3ef45394acd846d561657bba4c1dc613f Mon Sep 17 00:00:00 2001 From: Troy Kisky Date: Thu, 19 Jul 2012 08:18:19 +0000 Subject: mxc_i2c: add bus recovery support Add support for calling a function that will toggle the SCL line to return the bus to idle condition. The actual toggling function is added in a later patch. Signed-off-by: Troy Kisky --- drivers/i2c/mxc_i2c.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c index ead6e209b2..c00ead1f56 100644 --- a/drivers/i2c/mxc_i2c.c +++ b/drivers/i2c/mxc_i2c.c @@ -251,6 +251,8 @@ static int i2c_init_transfer_(struct mxc_i2c_regs *i2c_regs, return 0; } +static int i2c_idle_bus(void *base); + static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs, uchar chip, uint addr, int alen) { @@ -269,6 +271,8 @@ static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs, if (ret != -ERESTART) writeb(0, &i2c_regs->i2cr); /* Disable controller */ udelay(100); + if (i2c_idle_bus(i2c_regs) < 0) + break; } printf("%s: give up i2c_regs=%p\n", __func__, i2c_regs); return ret; @@ -390,6 +394,28 @@ void *get_base(void) #endif } +static struct i2c_parms *i2c_get_parms(void *base) +{ + int i = 0; + struct i2c_parms *p = srdata.i2c_data; + while (i < ARRAY_SIZE(srdata.i2c_data)) { + if (p->base == base) + return p; + p++; + i++; + } + printf("Invalid I2C base: %p\n", base); + return NULL; +} + +static int i2c_idle_bus(void *base) +{ + struct i2c_parms *p = i2c_get_parms(base); + if (p && p->idle_bus_fn) + return p->idle_bus_fn(p->idle_bus_data); + return 0; +} + int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len) { return bus_i2c_read(get_base(), chip, addr, alen, buf, len); -- cgit v1.2.3