xref: /OK3568_Linux_fs/u-boot/drivers/i2c/muxes/pca954x.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (C) 2015 - 2016 Xilinx, Inc.
3*4882a593Smuzhiyun  * Written by Michal Simek
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <common.h>
9*4882a593Smuzhiyun #include <dm.h>
10*4882a593Smuzhiyun #include <errno.h>
11*4882a593Smuzhiyun #include <i2c.h>
12*4882a593Smuzhiyun #include <asm/gpio.h>
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun DECLARE_GLOBAL_DATA_PTR;
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun enum pca_type {
17*4882a593Smuzhiyun 	PCA9544,
18*4882a593Smuzhiyun 	PCA9547,
19*4882a593Smuzhiyun 	PCA9548
20*4882a593Smuzhiyun };
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun struct chip_desc {
23*4882a593Smuzhiyun 	u8 enable;
24*4882a593Smuzhiyun 	enum muxtype {
25*4882a593Smuzhiyun 		pca954x_ismux = 0,
26*4882a593Smuzhiyun 		pca954x_isswi,
27*4882a593Smuzhiyun 	} muxtype;
28*4882a593Smuzhiyun };
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun struct pca954x_priv {
31*4882a593Smuzhiyun 	u32 addr; /* I2C mux address */
32*4882a593Smuzhiyun 	u32 width; /* I2C mux width - number of busses */
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun static const struct chip_desc chips[] = {
36*4882a593Smuzhiyun 	[PCA9544] = {
37*4882a593Smuzhiyun 		.enable = 0x4,
38*4882a593Smuzhiyun 		.muxtype = pca954x_ismux,
39*4882a593Smuzhiyun 	},
40*4882a593Smuzhiyun 	[PCA9547] = {
41*4882a593Smuzhiyun 		.enable = 0x8,
42*4882a593Smuzhiyun 		.muxtype = pca954x_ismux,
43*4882a593Smuzhiyun 	},
44*4882a593Smuzhiyun 	[PCA9548] = {
45*4882a593Smuzhiyun 		.enable = 0x8,
46*4882a593Smuzhiyun 		.muxtype = pca954x_isswi,
47*4882a593Smuzhiyun 	},
48*4882a593Smuzhiyun };
49*4882a593Smuzhiyun 
pca954x_deselect(struct udevice * mux,struct udevice * bus,uint channel)50*4882a593Smuzhiyun static int pca954x_deselect(struct udevice *mux, struct udevice *bus,
51*4882a593Smuzhiyun 			    uint channel)
52*4882a593Smuzhiyun {
53*4882a593Smuzhiyun 	struct pca954x_priv *priv = dev_get_priv(mux);
54*4882a593Smuzhiyun 	uchar byte = 0;
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun 	return dm_i2c_write(mux, priv->addr, &byte, 1);
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun 
pca954x_select(struct udevice * mux,struct udevice * bus,uint channel)59*4882a593Smuzhiyun static int pca954x_select(struct udevice *mux, struct udevice *bus,
60*4882a593Smuzhiyun 			  uint channel)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun 	struct pca954x_priv *priv = dev_get_priv(mux);
63*4882a593Smuzhiyun 	const struct chip_desc *chip = &chips[dev_get_driver_data(mux)];
64*4882a593Smuzhiyun 	uchar byte;
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun 	if (chip->muxtype == pca954x_ismux)
67*4882a593Smuzhiyun 		byte = channel | chip->enable;
68*4882a593Smuzhiyun 	else
69*4882a593Smuzhiyun 		byte = 1 << channel;
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun 	return dm_i2c_write(mux, priv->addr, &byte, 1);
72*4882a593Smuzhiyun }
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun static const struct i2c_mux_ops pca954x_ops = {
75*4882a593Smuzhiyun 	.select = pca954x_select,
76*4882a593Smuzhiyun 	.deselect = pca954x_deselect,
77*4882a593Smuzhiyun };
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun static const struct udevice_id pca954x_ids[] = {
80*4882a593Smuzhiyun 	{ .compatible = "nxp,pca9544", .data = PCA9544 },
81*4882a593Smuzhiyun 	{ .compatible = "nxp,pca9547", .data = PCA9547 },
82*4882a593Smuzhiyun 	{ .compatible = "nxp,pca9548", .data = PCA9548 },
83*4882a593Smuzhiyun 	{ }
84*4882a593Smuzhiyun };
85*4882a593Smuzhiyun 
pca954x_ofdata_to_platdata(struct udevice * dev)86*4882a593Smuzhiyun static int pca954x_ofdata_to_platdata(struct udevice *dev)
87*4882a593Smuzhiyun {
88*4882a593Smuzhiyun 	struct pca954x_priv *priv = dev_get_priv(dev);
89*4882a593Smuzhiyun 
90*4882a593Smuzhiyun 	priv->addr = dev_read_u32_default(dev, "reg", 0);
91*4882a593Smuzhiyun 	if (!priv->addr) {
92*4882a593Smuzhiyun 		debug("MUX not found\n");
93*4882a593Smuzhiyun 		return -ENODEV;
94*4882a593Smuzhiyun 	}
95*4882a593Smuzhiyun 	priv->width = dev_get_driver_data(dev);
96*4882a593Smuzhiyun 
97*4882a593Smuzhiyun 	if (!priv->width) {
98*4882a593Smuzhiyun 		debug("No I2C MUX width specified\n");
99*4882a593Smuzhiyun 		return -EINVAL;
100*4882a593Smuzhiyun 	}
101*4882a593Smuzhiyun 
102*4882a593Smuzhiyun 	debug("Device %s at 0x%x with width %d\n",
103*4882a593Smuzhiyun 	      dev->name, priv->addr, priv->width);
104*4882a593Smuzhiyun 
105*4882a593Smuzhiyun 	return 0;
106*4882a593Smuzhiyun }
107*4882a593Smuzhiyun 
108*4882a593Smuzhiyun U_BOOT_DRIVER(pca954x) = {
109*4882a593Smuzhiyun 	.name = "pca954x",
110*4882a593Smuzhiyun 	.id = UCLASS_I2C_MUX,
111*4882a593Smuzhiyun 	.of_match = pca954x_ids,
112*4882a593Smuzhiyun 	.ops = &pca954x_ops,
113*4882a593Smuzhiyun 	.ofdata_to_platdata = pca954x_ofdata_to_platdata,
114*4882a593Smuzhiyun 	.priv_auto_alloc_size = sizeof(struct pca954x_priv),
115*4882a593Smuzhiyun };
116