1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2015 - 2016 Xilinx, Inc.
4 * Copyright (C) 2017 National Instruments Corp
5 * Written by Michal Simek
6 */
7
8 #include <common.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <i2c.h>
12
13 #include <asm-generic/gpio.h>
14
15 DECLARE_GLOBAL_DATA_PTR;
16
17 enum pca_type {
18 PCA9543,
19 PCA9544,
20 PCA9547,
21 PCA9548,
22 PCA9646
23 };
24
25 struct chip_desc {
26 u8 enable; /* Enable mask in ctl register (used for muxes only) */
27 enum muxtype {
28 pca954x_ismux = 0,
29 pca954x_isswi,
30 } muxtype;
31 u32 width;
32 };
33
34 struct pca954x_priv {
35 u32 addr; /* I2C mux address */
36 u32 width; /* I2C mux width - number of busses */
37 struct gpio_desc gpio_mux_reset;
38 };
39
40 static const struct chip_desc chips[] = {
41 [PCA9543] = {
42 .muxtype = pca954x_isswi,
43 .width = 2,
44 },
45 [PCA9544] = {
46 .enable = 0x4,
47 .muxtype = pca954x_ismux,
48 .width = 4,
49 },
50 [PCA9547] = {
51 .enable = 0x8,
52 .muxtype = pca954x_ismux,
53 .width = 8,
54 },
55 [PCA9548] = {
56 .muxtype = pca954x_isswi,
57 .width = 8,
58 },
59 [PCA9646] = {
60 .muxtype = pca954x_isswi,
61 .width = 4,
62 },
63 };
64
pca954x_deselect(struct udevice * mux,struct udevice * bus,uint channel)65 static int pca954x_deselect(struct udevice *mux, struct udevice *bus,
66 uint channel)
67 {
68 struct pca954x_priv *priv = dev_get_priv(mux);
69 uchar byte = 0;
70
71 return dm_i2c_write(mux, priv->addr, &byte, 1);
72 }
73
pca954x_select(struct udevice * mux,struct udevice * bus,uint channel)74 static int pca954x_select(struct udevice *mux, struct udevice *bus,
75 uint channel)
76 {
77 struct pca954x_priv *priv = dev_get_priv(mux);
78 const struct chip_desc *chip = &chips[dev_get_driver_data(mux)];
79 uchar byte;
80
81 if (chip->muxtype == pca954x_ismux)
82 byte = channel | chip->enable;
83 else
84 byte = 1 << channel;
85
86 return dm_i2c_write(mux, priv->addr, &byte, 1);
87 }
88
89 static const struct i2c_mux_ops pca954x_ops = {
90 .select = pca954x_select,
91 .deselect = pca954x_deselect,
92 };
93
94 static const struct udevice_id pca954x_ids[] = {
95 { .compatible = "nxp,pca9543", .data = PCA9543 },
96 { .compatible = "nxp,pca9544", .data = PCA9544 },
97 { .compatible = "nxp,pca9547", .data = PCA9547 },
98 { .compatible = "nxp,pca9548", .data = PCA9548 },
99 { .compatible = "nxp,pca9646", .data = PCA9646 },
100 { }
101 };
102
pca954x_ofdata_to_platdata(struct udevice * dev)103 static int pca954x_ofdata_to_platdata(struct udevice *dev)
104 {
105 struct pca954x_priv *priv = dev_get_priv(dev);
106 const struct chip_desc *chip = &chips[dev_get_driver_data(dev)];
107
108 priv->addr = dev_read_u32_default(dev, "reg", 0);
109 if (!priv->addr) {
110 debug("MUX not found\n");
111 return -ENODEV;
112 }
113 priv->width = chip->width;
114
115 if (!priv->width) {
116 debug("No I2C MUX width specified\n");
117 return -EINVAL;
118 }
119
120 debug("Device %s at 0x%x with width %d\n",
121 dev->name, priv->addr, priv->width);
122
123 return 0;
124 }
125
pca954x_probe(struct udevice * dev)126 static int pca954x_probe(struct udevice *dev)
127 {
128 if (IS_ENABLED(CONFIG_DM_GPIO)) {
129 struct pca954x_priv *priv = dev_get_priv(dev);
130 int err;
131
132 err = gpio_request_by_name(dev, "reset-gpios", 0,
133 &priv->gpio_mux_reset, GPIOD_IS_OUT);
134
135 /* it's optional so only bail if we get a real error */
136 if (err && (err != -ENOENT))
137 return err;
138
139 /* dm will take care of polarity */
140 if (dm_gpio_is_valid(&priv->gpio_mux_reset))
141 dm_gpio_set_value(&priv->gpio_mux_reset, 0);
142 }
143
144 return 0;
145 }
146
pca954x_remove(struct udevice * dev)147 static int pca954x_remove(struct udevice *dev)
148 {
149 if (IS_ENABLED(CONFIG_DM_GPIO)) {
150 struct pca954x_priv *priv = dev_get_priv(dev);
151
152 if (dm_gpio_is_valid(&priv->gpio_mux_reset))
153 dm_gpio_free(dev, &priv->gpio_mux_reset);
154 }
155
156 return 0;
157 }
158
159 U_BOOT_DRIVER(pca954x) = {
160 .name = "pca954x",
161 .id = UCLASS_I2C_MUX,
162 .of_match = pca954x_ids,
163 .probe = pca954x_probe,
164 .remove = pca954x_remove,
165 .ops = &pca954x_ops,
166 .ofdata_to_platdata = pca954x_ofdata_to_platdata,
167 .priv_auto_alloc_size = sizeof(struct pca954x_priv),
168 };
169