3  * Mellanox i2c mux driver
10 #include <linux/i2c-mux.h>
18 /* mlxcpld_mux - mux control structure:
19  * @last_val - last selected register value or -1 if mux deselected
29 /* MUX logic description.
30  * Driver can support different mux control logic, according to CPLD
37  * *--------*                                 * -> mux1 (virt bus2) -> mux -> |
38  * | I2CLPC | i2c physical                    * -> mux2 (virt bus3) -> mux -> |
40  * | logic  |---------------------> * mux reg *                               |
42  * *--------*   i2c-mux-mlxpcld          ^    * -> muxn (virt busn) -> mux -> |
47  *     |        * mux selection * deselect
52  * reg space      space (mux select,
57 /* Write to mux register. Don't use i2c_transfer() and i2c_smbus_xfer()
61 				 struct mlxcpld_mux *mux, u32 val)  in mlxcpld_mux_reg_write()  argument
63 	struct i2c_client *client = mux->client;  in mlxcpld_mux_reg_write()
68 	switch (mux->pdata.reg_size) {  in mlxcpld_mux_reg_write()
72 					I2C_SMBUS_WRITE, mux->pdata.sel_reg_addr,  in mlxcpld_mux_reg_write()
75 		buf[0] = mux->pdata.sel_reg_addr >> 8;  in mlxcpld_mux_reg_write()
76 		buf[1] = mux->pdata.sel_reg_addr;  in mlxcpld_mux_reg_write()
80 		msg.len = mux->pdata.reg_size + 1;  in mlxcpld_mux_reg_write()
90 	struct mlxcpld_mux *mux = i2c_mux_priv(muxc);  in mlxcpld_mux_select_chan()  local
94 	if (mux->pdata.reg_size == 1)  in mlxcpld_mux_select_chan()
98 	if (mux->last_val != regval) {  in mlxcpld_mux_select_chan()
99 		err = mlxcpld_mux_reg_write(muxc->parent, mux, regval);  in mlxcpld_mux_select_chan()
100 		mux->last_val = err < 0 ? -1 : regval;  in mlxcpld_mux_select_chan()
108 	struct mlxcpld_mux *mux = i2c_mux_priv(muxc);  in mlxcpld_mux_deselect()  local
111 	mux->last_val = -1;  in mlxcpld_mux_deselect()
113 	return mlxcpld_mux_reg_write(muxc->parent, mux, 0);  in mlxcpld_mux_deselect()
183 		.name = "i2c-mux-mlxcpld",
192 MODULE_DESCRIPTION("Mellanox I2C-CPLD-MUX driver");
194 MODULE_ALIAS("platform:i2c-mux-mlxcpld");