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 #include <log.h>
13 #include <malloc.h>
14 #include <asm/global_data.h>
15
16 #include <asm-generic/gpio.h>
17
18 DECLARE_GLOBAL_DATA_PTR;
19
20 enum pca_type {
21 PCA9543,
22 PCA9544,
23 PCA9546,
24 PCA9547,
25 PCA9548,
26 PCA9646
27 };
28
29 struct chip_desc {
30 u8 enable; /* Enable mask in ctl register (used for muxes only) */
31 enum muxtype {
32 pca954x_ismux = 0,
33 pca954x_isswi,
34 } muxtype;
35 u32 width;
36 };
37
38 struct pca954x_priv {
39 u32 addr; /* I2C mux address */
40 u32 width; /* I2C mux width - number of busses */
41 struct gpio_desc gpio_mux_reset;
42 };
43
44 static const struct chip_desc chips[] = {
45 [PCA9543] = {
46 .muxtype = pca954x_isswi,
47 .width = 2,
48 },
49 [PCA9544] = {
50 .enable = 0x4,
51 .muxtype = pca954x_ismux,
52 .width = 4,
53 },
54 [PCA9546] = {
55 .muxtype = pca954x_isswi,
56 .width = 4,
57 },
58 [PCA9547] = {
59 .enable = 0x8,
60 .muxtype = pca954x_ismux,
61 .width = 8,
62 },
63 [PCA9548] = {
64 .muxtype = pca954x_isswi,
65 .width = 8,
66 },
67 [PCA9646] = {
68 .muxtype = pca954x_isswi,
69 .width = 4,
70 },
71 };
72
pca954x_deselect(struct udevice * mux,struct udevice * bus,uint channel)73 static int pca954x_deselect(struct udevice *mux, struct udevice *bus,
74 uint channel)
75 {
76 struct pca954x_priv *priv = dev_get_priv(mux);
77 uchar byte = 0;
78
79 return dm_i2c_write(mux, priv->addr, &byte, 1);
80 }
81
pca954x_select(struct udevice * mux,struct udevice * bus,uint channel)82 static int pca954x_select(struct udevice *mux, struct udevice *bus,
83 uint channel)
84 {
85 struct pca954x_priv *priv = dev_get_priv(mux);
86 const struct chip_desc *chip = &chips[dev_get_driver_data(mux)];
87 uchar byte;
88
89 if (chip->muxtype == pca954x_ismux)
90 byte = channel | chip->enable;
91 else
92 byte = 1 << channel;
93
94 return dm_i2c_write(mux, priv->addr, &byte, 1);
95 }
96
97 static const struct i2c_mux_ops pca954x_ops = {
98 .select = pca954x_select,
99 .deselect = pca954x_deselect,
100 };
101
102 static const struct udevice_id pca954x_ids[] = {
103 { .compatible = "nxp,pca9543", .data = PCA9543 },
104 { .compatible = "nxp,pca9544", .data = PCA9544 },
105 { .compatible = "nxp,pca9546", .data = PCA9546 },
106 { .compatible = "nxp,pca9547", .data = PCA9547 },
107 { .compatible = "nxp,pca9548", .data = PCA9548 },
108 { .compatible = "nxp,pca9646", .data = PCA9646 },
109 { }
110 };
111
pca954x_of_to_plat(struct udevice * dev)112 static int pca954x_of_to_plat(struct udevice *dev)
113 {
114 struct pca954x_priv *priv = dev_get_priv(dev);
115 const struct chip_desc *chip = &chips[dev_get_driver_data(dev)];
116
117 priv->addr = dev_read_u32_default(dev, "reg", 0);
118 if (!priv->addr) {
119 debug("MUX not found\n");
120 return -ENODEV;
121 }
122 priv->width = chip->width;
123
124 if (!priv->width) {
125 debug("No I2C MUX width specified\n");
126 return -EINVAL;
127 }
128
129 debug("Device %s at 0x%x with width %d\n",
130 dev->name, priv->addr, priv->width);
131
132 return 0;
133 }
134
pca954x_probe(struct udevice * dev)135 static int pca954x_probe(struct udevice *dev)
136 {
137 if (CONFIG_IS_ENABLED(DM_GPIO)) {
138 struct pca954x_priv *priv = dev_get_priv(dev);
139 int err;
140
141 err = gpio_request_by_name(dev, "reset-gpios", 0,
142 &priv->gpio_mux_reset, GPIOD_IS_OUT);
143
144 /* it's optional so only bail if we get a real error */
145 if (err && (err != -ENOENT))
146 return err;
147
148 /* dm will take care of polarity */
149 if (dm_gpio_is_valid(&priv->gpio_mux_reset))
150 dm_gpio_set_value(&priv->gpio_mux_reset, 0);
151 }
152
153 return 0;
154 }
155
pca954x_remove(struct udevice * dev)156 static int pca954x_remove(struct udevice *dev)
157 {
158 if (CONFIG_IS_ENABLED(DM_GPIO)) {
159 struct pca954x_priv *priv = dev_get_priv(dev);
160
161 if (dm_gpio_is_valid(&priv->gpio_mux_reset))
162 dm_gpio_free(dev, &priv->gpio_mux_reset);
163 }
164
165 return 0;
166 }
167
168 U_BOOT_DRIVER(pca954x) = {
169 .name = "pca954x",
170 .id = UCLASS_I2C_MUX,
171 .of_match = pca954x_ids,
172 .probe = pca954x_probe,
173 .remove = pca954x_remove,
174 .ops = &pca954x_ops,
175 .of_to_plat = pca954x_of_to_plat,
176 .priv_auto = sizeof(struct pca954x_priv),
177 };
178