[PATCH 18/30] via: Do not attempt I/O on inactive I2C adapters

Jonathan Corbet
2010-04-28T22:21:20Z

If an adapter has been configured for GPIO (or off), we should not try to
use it as an I2C port.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
---
drivers/video/via/via_i2c.c | 14 ++++++++++----
drivers/video/via/via_i2c.h | 1 +
2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/video/via/via_i2c.c b/drivers/video/via/via_i2c.c
index 3ff60b2..c88450e 100644
--- a/drivers/video/via/via_i2c.c
+++ b/drivers/video/via/via_i2c.c
@@ -115,6 +115,8 @@ int viafb_i2c_readbyte(u8 adap, u8 slave_addr, u8 index, u8 *pdata)
u8 mm1[] = {0x00};
struct i2c_msg msgs[2];

+ if (!via_i2c_par[adap].is_active)
+ return -ENODEV;
*pdata = 0;
msgs[0].flags = 0;
msgs[1].flags = I2C_M_RD;
@@ -130,6 +132,8 @@ int viafb_i2c_writebyte(u8 adap, u8 slave_addr, u8 index, u8 data)
u8 msg[2] = { index, data };
struct i2c_msg msgs;

+ if (!via_i2c_par[adap].is_active)
+ return -ENODEV;
msgs.flags = 0;
msgs.addr = slave_addr / 2;
msgs.len = 2;
@@ -142,6 +146,8 @@ int viafb_i2c_readbytes(u8 adap, u8 slave_addr, u8 index, u8 *buff, int buff_len
u8 mm1[] = {0x00};
struct i2c_msg msgs[2];

+ if (!via_i2c_par[adap].is_active)
+ return -ENODEV;
msgs[0].flags = 0;
msgs[1].flags = I2C_M_RD;
msgs[0].addr = msgs[1].addr = slave_addr / 2;
@@ -198,18 +204,18 @@ static int viafb_i2c_probe(struct platform_device *platdev)
struct via_port_cfg *adap_cfg = configs++;
struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];

+ i2c_stuff->is_active = 0;
if (adap_cfg->type == 0 || adap_cfg->mode != VIA_MODE_I2C)
continue;
-
ret = create_i2c_bus(&i2c_stuff->adapter,
&i2c_stuff->algo, adap_cfg,
NULL); /* FIXME: PCIDEV */
if (ret < 0) {
printk(KERN_ERR "viafb: cannot create i2c bus %u:%d\n",
i, ret);
- /* FIXME: properly release previous busses */
- return ret;
+ continue; /* Still try to make the rest */
}
+ i2c_stuff->is_active = 1;
}

return 0;
@@ -225,7 +231,7 @@ static int viafb_i2c_remove(struct platform_device *platdev)
* Only remove those entries in the array that we've
* actually used (and thus initialized algo_data)
*/
- if (i2c_stuff->adapter.algo_data == &i2c_stuff->algo)
+ if (i2c_stuff->is_active)
i2c_del_adapter(&i2c_stuff->adapter);
}
return 0;
diff --git a/drivers/video/via/via_i2c.h b/drivers/video/via/via_i2c.h
index b2332cc..1d18e7d 100644
--- a/drivers/video/via/via_i2c.h
+++ b/drivers/video/via/via_i2c.h
@@ -26,6 +26,7 @@

struct via_i2c_stuff {
u16 i2c_port; /* GPIO or I2C port */
+ u16 is_active; /* Being used as I2C? */
struct i2c_adapter adapter;
struct i2c_algo_bit_data algo;
};
--
1.7.0.1