Extend driver to allow I2C routing control through CPLD devices with
word address space. Till now only CPLD devices with byte address space
have been supported.
Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxx>
Reviewed-by: Michael Shych <michaelsh@xxxxxxxxxx>
---
v2->v3:
Comments pointed out by Peter:
- Do not change mlxcpld_mux_reg_write() argumnet "val" to "chan",
since it is misleading for the one-byte case.
- Drop cpu_to_be16() conversion from mlxcpld_mux_reg_write().
v1->v2:
Comments pointed out by Peter:
- Remove data buffer allocation from 'mlxcpld_mux' structure, do it on
stack instead.
- Do not use array pdata.adap_ids[] in mlxcpld_mux_reg_write() for
channel assignment.
- Return back 'regval' variable, used for channel assignment in
mlxcpld_mux_select_chan().
- Fix functionality validation in mlxcpld_mux_probe().
- Fix comment for 'reg_size' field in mlxcpld_mux_plat_data' structure.
Added by Vadim:
- Change type of register select address to '__be16' to align with
type in assignment in cpu_to_be16().
---
drivers/i2c/muxes/i2c-mux-mlxcpld.c | 47 +++++++++++++++++++++++++++++------
include/linux/platform_data/mlxcpld.h | 2 ++
2 files changed, 41 insertions(+), 8 deletions(-)
diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index 9e9d74bd1059..71d4b8813704 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -63,19 +63,39 @@ static int mlxcpld_mux_reg_write(struct i2c_adapter *adap,
struct mlxcpld_mux *mux, u32 val)
{
struct i2c_client *client = mux->client;
- union i2c_smbus_data data = { .byte = val };
-
- return __i2c_smbus_xfer(adap, client->addr, client->flags,
- I2C_SMBUS_WRITE, mux->pdata.sel_reg_addr,
- I2C_SMBUS_BYTE_DATA, &data);
+ union i2c_smbus_data data;
+ struct i2c_msg msg;
+ u8 buf[3];
+
+ switch (mux->pdata.reg_size) {
+ case 1:
+ data.byte = val;
+ return __i2c_smbus_xfer(adap, client->addr, client->flags,
+ I2C_SMBUS_WRITE, mux->pdata.sel_reg_addr,
+ I2C_SMBUS_BYTE_DATA, &data);
+ case 2:
+ buf[0] = mux->pdata.sel_reg_addr >> 8;
+ buf[1] = mux->pdata.sel_reg_addr;
+ buf[2] = val;
+ msg.addr = client->addr;
+ msg.buf = buf;
+ msg.len = mux->pdata.reg_size + 1;
+ msg.flags = 0;
+ return __i2c_transfer(adap, &msg, 1);
+ default:
+ return -EINVAL;
+ }
}
static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
struct mlxcpld_mux *mux = i2c_mux_priv(muxc);
- u32 regval = chan + 1;
+ u32 regval = chan;
int err = 0;
+ if (mux->pdata.reg_size == 1)
+ regval += 1;
+
/* Only select the channel if its different from the last channel */
if (mux->last_val != regval) {
err = mlxcpld_mux_reg_write(muxc->parent, mux, regval);
@@ -103,13 +123,24 @@ static int mlxcpld_mux_probe(struct platform_device *pdev)
struct i2c_mux_core *muxc;
int num, force;
struct mlxcpld_mux *data;
+ u32 func;
int err;
if (!pdata)
return -EINVAL;
- if (!i2c_check_functionality(client->adapter,
- I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+ switch (pdata->reg_size) {
+ case 1:
+ func = I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
+ break;
+ case 2:
+ func = I2C_FUNC_I2C;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (!i2c_check_functionality(client->adapter, func))
return -ENODEV;
muxc = i2c_mux_alloc(client->adapter, &pdev->dev, CPLD_MUX_MAX_NCHANS,
diff --git a/include/linux/platform_data/mlxcpld.h b/include/linux/platform_data/mlxcpld.h
index 04d93c563c04..a7bee798d991 100644
--- a/include/linux/platform_data/mlxcpld.h
+++ b/include/linux/platform_data/mlxcpld.h
@@ -14,11 +14,13 @@
* @chan_ids - channels array
* @num_adaps - number of adapters
* @sel_reg_addr - mux select register offset in CPLD space
+ * @reg_size: register size in bytes
*/
struct mlxcpld_mux_plat_data {
int *chan_ids;
int num_adaps;
int sel_reg_addr;
+ u8 reg_size;
};
#endif /* _LINUX_I2C_MLXCPLD_H */
--
2.11.0
