1 /*
2  * Copyright (C) EETS GmbH, 2017, Felix Brack <f.brack@eets.ch>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <dm/pinctrl.h>
10 #include <linux/libfdt.h>
11 #include <asm/io.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
15 struct single_pdata {
16 	fdt_addr_t base;	/* first configuration register */
17 	int offset;		/* index of last configuration register */
18 	u32 mask;		/* configuration-value mask bits */
19 	int width;		/* configuration register bit width */
20 };
21 
22 struct single_fdt_pin_cfg {
23 	fdt32_t reg;		/* configuration register offset */
24 	fdt32_t val;		/* configuration register value */
25 };
26 
27 /**
28  * single_configure_pins() - Configure pins based on FDT data
29  *
30  * @dev: Pointer to single pin configuration device which is the parent of
31  *       the pins node holding the pin configuration data.
32  * @pins: Pointer to the first element of an array of register/value pairs
33  *        of type 'struct single_fdt_pin_cfg'. Each such pair describes the
34  *        the pin to be configured and the value to be used for configuration.
35  *        This pointer points to a 'pinctrl-single,pins' property in the
36  *        device-tree.
37  * @size: Size of the 'pins' array in bytes.
38  *        The number of register/value pairs in the 'pins' array therefore
39  *        equals to 'size / sizeof(struct single_fdt_pin_cfg)'.
40  */
41 static int single_configure_pins(struct udevice *dev,
42 				 const struct single_fdt_pin_cfg *pins,
43 				 int size)
44 {
45 	struct single_pdata *pdata = dev->platdata;
46 	int count = size / sizeof(struct single_fdt_pin_cfg);
47 	int n, reg;
48 	u32 val;
49 
50 	for (n = 0; n < count; n++, pins++) {
51 		reg = fdt32_to_cpu(pins->reg);
52 		if ((reg < 0) || (reg > pdata->offset)) {
53 			dev_dbg(dev, "  invalid register offset 0x%08x\n", reg);
54 			continue;
55 		}
56 		reg += pdata->base;
57 		val = fdt32_to_cpu(pins->val) & pdata->mask;
58 		switch (pdata->width) {
59 		case 16:
60 			writew((readw(reg) & ~pdata->mask) | val, reg);
61 			break;
62 		case 32:
63 			writel((readl(reg) & ~pdata->mask) | val, reg);
64 			break;
65 		default:
66 			dev_warn(dev, "unsupported register width %i\n",
67 				 pdata->width);
68 			continue;
69 		}
70 		dev_dbg(dev, "  reg/val 0x%08x/0x%08x\n",reg, val);
71 	}
72 	return 0;
73 }
74 
75 static int single_set_state(struct udevice *dev,
76 			    struct udevice *config)
77 {
78 	const void *fdt = gd->fdt_blob;
79 	const struct single_fdt_pin_cfg *prop;
80 	int len;
81 
82 	prop = fdt_getprop(fdt, dev_of_offset(config), "pinctrl-single,pins",
83 			   &len);
84 	if (prop) {
85 		dev_dbg(dev, "configuring pins for %s\n", config->name);
86 		if (len % sizeof(struct single_fdt_pin_cfg)) {
87 			dev_dbg(dev, "  invalid pin configuration in fdt\n");
88 			return -FDT_ERR_BADSTRUCTURE;
89 		}
90 		single_configure_pins(dev, prop, len);
91 		len = 0;
92 	}
93 
94 	return len;
95 }
96 
97 static int single_ofdata_to_platdata(struct udevice *dev)
98 {
99 	fdt_addr_t addr;
100 	u32 of_reg[2];
101 	int res;
102 	struct single_pdata *pdata = dev->platdata;
103 
104 	pdata->width = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
105 				      "pinctrl-single,register-width", 0);
106 
107 	res = fdtdec_get_int_array(gd->fdt_blob, dev_of_offset(dev),
108 				   "reg", of_reg, 2);
109 	if (res)
110 		return res;
111 	pdata->offset = of_reg[1] - pdata->width / 8;
112 
113 	addr = devfdt_get_addr(dev);
114 	if (addr == FDT_ADDR_T_NONE) {
115 		dev_dbg(dev, "no valid base register address\n");
116 		return -EINVAL;
117 	}
118 	pdata->base = addr;
119 
120 	pdata->mask = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
121 				     "pinctrl-single,function-mask",
122 				     0xffffffff);
123 	return 0;
124 }
125 
126 const struct pinctrl_ops single_pinctrl_ops = {
127 	.set_state = single_set_state,
128 };
129 
130 static const struct udevice_id single_pinctrl_match[] = {
131 	{ .compatible = "pinctrl-single" },
132 	{ /* sentinel */ }
133 };
134 
135 U_BOOT_DRIVER(single_pinctrl) = {
136 	.name = "single-pinctrl",
137 	.id = UCLASS_PINCTRL,
138 	.of_match = single_pinctrl_match,
139 	.ops = &single_pinctrl_ops,
140 	.flags = DM_FLAG_PRE_RELOC,
141 	.platdata_auto_alloc_size = sizeof(struct single_pdata),
142 	.ofdata_to_platdata = single_ofdata_to_platdata,
143 };
144