i2c/muxes/i2c-mux-mlxcpld.c

2  * drivers/i2c/muxes/i2c-mux-mlxcpld.c
14  * 3. Neither the names of the copyright holders nor the names of its
37 #include <linux/i2c-mux.h>
47 /* mlxcpld_mux - mux control structure:
48  * @last_chan - last register value
49  * @client - I2C device client
62  * i2c-mlxcpld                                 Digital               Analog
64  * *--------*                                 * -> mux1 (virt bus2) -> mux -> |
65  * | I2CLPC | i2c physical                    * -> mux2 (virt bus3) -> mux -> |
66  * | bridge | bus 1                 *---------*                               |
67  * | logic  |---------------------> * mux reg *                               |
68  * | in CPLD|                       *---------*                               |
69  * *--------*   i2c-mux-mlxpcld          ^    * -> muxn (virt busn) -> mux -> |
71  *     |        *---------------*        |                              Devices
73  *     |        * registers for *--------*
75  *     |        *---------------*
77  * <-------->     <----------->
78  * i2c cntrl      Board cntrl reg
79  * reg space      space (mux select,
96 	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);  in mlxcpld_mux_reg_write()
99 	return __i2c_smbus_xfer(adap, client->addr, client->flags,  in mlxcpld_mux_reg_write()
100 				I2C_SMBUS_WRITE, pdata->sel_reg_addr,  in mlxcpld_mux_reg_write()
107 	struct i2c_client *client = data->client;  in mlxcpld_mux_select_chan()
112 	if (data->last_chan != regval) {  in mlxcpld_mux_select_chan()
113 		err = mlxcpld_mux_reg_write(muxc->parent, client, regval);  in mlxcpld_mux_select_chan()
114 		data->last_chan = err < 0 ? 0 : regval;  in mlxcpld_mux_select_chan()
123 	struct i2c_client *client = data->client;  in mlxcpld_mux_deselect()
126 	data->last_chan = 0;  in mlxcpld_mux_deselect()
128 	return mlxcpld_mux_reg_write(muxc->parent, client, data->last_chan);  in mlxcpld_mux_deselect()
135 	struct i2c_adapter *adap = client->adapter;  in mlxcpld_mux_probe()
136 	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);  in mlxcpld_mux_probe()
143 		return -EINVAL;  in mlxcpld_mux_probe()
146 		return -ENODEV;  in mlxcpld_mux_probe()
148 	muxc = i2c_mux_alloc(adap, &client->dev, CPLD_MUX_MAX_NCHANS,  in mlxcpld_mux_probe()
152 		return -ENOMEM;  in mlxcpld_mux_probe()
156 	data->client = client;  in mlxcpld_mux_probe()
157 	data->last_chan = 0; /* force the first selection */  in mlxcpld_mux_probe()
161 		if (num >= pdata->num_adaps)  in mlxcpld_mux_probe()
165 		force = pdata->adap_ids[num];  in mlxcpld_mux_probe()
189 		.name	= "mlxcpld-mux",
199 MODULE_DESCRIPTION("Mellanox I2C-CPLD-MUX driver");
201 MODULE_ALIAS("platform:i2c-mux-mlxcpld");