Commit c52a1c5f authored by Vadim Pasternak's avatar Vadim Pasternak Committed by Wolfram Sang
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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: default avatarVadim Pasternak <vadimp@nvidia.com>
Reviewed-by: default avatarMichael Shych <michaelsh@nvidia.com>
Acked-by: default avatarPeter Rosin <peda@axentia.se>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent cae52163

drivers/i2c/muxes/i2c-mux-mlxcpld.c

+39 −8
Original line number Diff line number Diff line
@@ -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 };

	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,

include/linux/platform_data/mlxcpld.h

+2 −0
Original line number Diff line number Diff line
@@ -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 */