i2c: mux: mlxcpld: Extend driver to support word address space devices

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@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index e99a7ad09886e10e0a8251cf47b24421f193a180..10767ad4adb4e8f51093e0aba5610a3b94486483 100644 (file)
--- 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);
@@ -103,12 +123,23 @@ static int mlxcpld_mux_probe(struct platform_device *pdev)
        struct i2c_mux_core *muxc;
        struct mlxcpld_mux *data;
        int num, err;
+       u32 func;
 
        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 04d93c563c04c24206654c5bad8d56272677baa5..a7bee798d99175f69f065b21e04a75cb63728db1 100644 (file)
--- 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 */