1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) EETS GmbH, 2017, Felix Brack <f.brack@eets.ch>
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <dm/pinctrl.h>
9 #include <linux/libfdt.h>
10 #include <asm/io.h>
11 
12 DECLARE_GLOBAL_DATA_PTR;
13 
14 struct single_pdata {
15 	fdt_addr_t base;	/* first configuration register */
16 	int offset;		/* index of last configuration register */
17 	u32 mask;		/* configuration-value mask bits */
18 	int width;		/* configuration register bit width */
19 };
20 
21 struct single_fdt_pin_cfg {
22 	fdt32_t reg;		/* configuration register offset */
23 	fdt32_t val;		/* configuration register value */
24 };
25 
26 /**
27  * single_configure_pins() - Configure pins based on FDT data
28  *
29  * @dev: Pointer to single pin configuration device which is the parent of
30  *       the pins node holding the pin configuration data.
31  * @pins: Pointer to the first element of an array of register/value pairs
32  *        of type 'struct single_fdt_pin_cfg'. Each such pair describes the
33  *        the pin to be configured and the value to be used for configuration.
34  *        This pointer points to a 'pinctrl-single,pins' property in the
35  *        device-tree.
36  * @size: Size of the 'pins' array in bytes.
37  *        The number of register/value pairs in the 'pins' array therefore
38  *        equals to 'size / sizeof(struct single_fdt_pin_cfg)'.
39  */
40 static int single_configure_pins(struct udevice *dev,
41 				 const struct single_fdt_pin_cfg *pins,
42 				 int size)
43 {
44 	struct single_pdata *pdata = dev->platdata;
45 	int count = size / sizeof(struct single_fdt_pin_cfg);
46 	phys_addr_t n, reg;
47 	u32 val;
48 
49 	for (n = 0; n < count; n++, pins++) {
50 		reg = fdt32_to_cpu(pins->reg);
51 		if ((reg < 0) || (reg > pdata->offset)) {
52 			dev_dbg(dev, "  invalid register offset 0x%pa\n", &reg);
53 			continue;
54 		}
55 		reg += pdata->base;
56 		val = fdt32_to_cpu(pins->val) & pdata->mask;
57 		switch (pdata->width) {
58 		case 16:
59 			writew((readw(reg) & ~pdata->mask) | val, reg);
60 			break;
61 		case 32:
62 			writel((readl(reg) & ~pdata->mask) | val, reg);
63 			break;
64 		default:
65 			dev_warn(dev, "unsupported register width %i\n",
66 				 pdata->width);
67 			continue;
68 		}
69 		dev_dbg(dev, "  reg/val 0x%pa/0x%08x\n", &reg, val);
70 	}
71 	return 0;
72 }
73 
74 static int single_set_state(struct udevice *dev,
75 			    struct udevice *config)
76 {
77 	const void *fdt = gd->fdt_blob;
78 	const struct single_fdt_pin_cfg *prop;
79 	int len;
80 
81 	prop = fdt_getprop(fdt, dev_of_offset(config), "pinctrl-single,pins",
82 			   &len);
83 	if (prop) {
84 		dev_dbg(dev, "configuring pins for %s\n", config->name);
85 		if (len % sizeof(struct single_fdt_pin_cfg)) {
86 			dev_dbg(dev, "  invalid pin configuration in fdt\n");
87 			return -FDT_ERR_BADSTRUCTURE;
88 		}
89 		single_configure_pins(dev, prop, len);
90 		len = 0;
91 	}
92 
93 	return len;
94 }
95 
96 static int single_ofdata_to_platdata(struct udevice *dev)
97 {
98 	fdt_addr_t addr;
99 	u32 of_reg[2];
100 	int res;
101 	struct single_pdata *pdata = dev->platdata;
102 
103 	pdata->width = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
104 				      "pinctrl-single,register-width", 0);
105 
106 	res = fdtdec_get_int_array(gd->fdt_blob, dev_of_offset(dev),
107 				   "reg", of_reg, 2);
108 	if (res)
109 		return res;
110 	pdata->offset = of_reg[1] - pdata->width / 8;
111 
112 	addr = devfdt_get_addr(dev);
113 	if (addr == FDT_ADDR_T_NONE) {
114 		dev_dbg(dev, "no valid base register address\n");
115 		return -EINVAL;
116 	}
117 	pdata->base = addr;
118 
119 	pdata->mask = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
120 				     "pinctrl-single,function-mask",
121 				     0xffffffff);
122 	return 0;
123 }
124 
125 const struct pinctrl_ops single_pinctrl_ops = {
126 	.set_state = single_set_state,
127 };
128 
129 static const struct udevice_id single_pinctrl_match[] = {
130 	{ .compatible = "pinctrl-single" },
131 	{ /* sentinel */ }
132 };
133 
134 U_BOOT_DRIVER(single_pinctrl) = {
135 	.name = "single-pinctrl",
136 	.id = UCLASS_PINCTRL,
137 	.of_match = single_pinctrl_match,
138 	.ops = &single_pinctrl_ops,
139 	.platdata_auto_alloc_size = sizeof(struct single_pdata),
140 	.ofdata_to_platdata = single_ofdata_to_platdata,
141 };
142