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