[PATCH 09/10] i2c: pca9541: get rid of the i2c deadlock workaround

Peter Rosin
2016-01-04T15:11:37Z

Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/muxes/i2c-mux-pca9541.c | 82 +++++++------------------------------
1 file changed, 15 insertions(+), 67 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index 9ee0d8b70283..7d2e5dbd8617 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -85,81 +85,28 @@ static const struct i2c_device_id pca9541_id[] = {

MODULE_DEVICE_TABLE(i2c, pca9541_id);

-/*
- * Write to chip register. Don't use i2c_transfer()/i2c_smbus_xfer()
- * as they will try to lock the adapter a second time.
- */
static int pca9541_reg_write(struct i2c_client *client, u8 command, u8 val)
{
- struct i2c_adapter *adap = client->adapter;
- int ret;
-
- if (adap->algo->master_xfer) {
- struct i2c_msg msg;
- char buf[2];
-
- msg.addr = client->addr;
- msg.flags = 0;
- msg.len = 2;
- buf[0] = command;
- buf[1] = val;
- msg.buf = buf;
- ret = __i2c_transfer(adap, &msg, 1);
- } else {
- union i2c_smbus_data data;
-
- data.byte = val;
- ret = adap->algo->smbus_xfer(adap, client->addr,
- client->flags,
- I2C_SMBUS_WRITE,
- command,
- I2C_SMBUS_BYTE_DATA, &data);
- }
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ union i2c_smbus_data data;

- return ret;
+ data.byte = val;
+ return i2c_smbus_xfer(muxc->parent, client->addr, client->flags,
+ I2C_SMBUS_WRITE, command,
+ I2C_SMBUS_BYTE_DATA, &data);
}

-/*
- * Read from chip register. Don't use i2c_transfer()/i2c_smbus_xfer()
- * as they will try to lock adapter a second time.
- */
static int pca9541_reg_read(struct i2c_client *client, u8 command)
{
- struct i2c_adapter *adap = client->adapter;
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ union i2c_smbus_data data;
int ret;
- u8 val;
-
- if (adap->algo->master_xfer) {
- struct i2c_msg msg[2] = {
- {
- .addr = client->addr,
- .flags = 0,
- .len = 1,
- .buf = &command
- },
- {
- .addr = client->addr,
- .flags = I2C_M_RD,
- .len = 1,
- .buf = &val
- }
- };
- ret = __i2c_transfer(adap, msg, 2);
- if (ret == 2)
- ret = val;
- else if (ret >= 0)
- ret = -EIO;
- } else {
- union i2c_smbus_data data;
-
- ret = adap->algo->smbus_xfer(adap, client->addr,
- client->flags,
- I2C_SMBUS_READ,
- command,
- I2C_SMBUS_BYTE_DATA, &data);
- if (!ret)
- ret = data.byte;
- }
+
+ ret = i2c_smbus_xfer(muxc->parent, client->addr, client->flags,
+ I2C_SMBUS_READ, command,
+ I2C_SMBUS_BYTE_DATA, &data);
+ if (!ret)
+ ret = data.byte;
return ret;
}

@@ -347,6 +294,7 @@ static int pca9541_probe(struct i2c_client *client,
i2c_set_clientdata(client, muxc);

data->client = client;
+ muxc->i2c_controlled = true;
muxc->parent = adap;
muxc->select = pca9541_select_chan;
muxc->deselect = pca9541_release_chan;
--
2.1.4