1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
4 // Author: Vignesh Raghavendra <vigneshr@ti.com>
5 
6 #include <linux/err.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/mtd/hyperbus.h>
10 #include <linux/mtd/map.h>
11 #include <linux/mtd/mtd.h>
12 #include <linux/of.h>
13 #include <linux/of_address.h>
14 #include <linux/types.h>
15 
16 static struct hyperbus_device *map_to_hbdev(struct map_info *map)
17 {
18 	return container_of(map, struct hyperbus_device, map);
19 }
20 
21 static map_word hyperbus_read16(struct map_info *map, unsigned long addr)
22 {
23 	struct hyperbus_device *hbdev = map_to_hbdev(map);
24 	struct hyperbus_ctlr *ctlr = hbdev->ctlr;
25 	map_word read_data;
26 
27 	read_data.x[0] = ctlr->ops->read16(hbdev, addr);
28 
29 	return read_data;
30 }
31 
32 static void hyperbus_write16(struct map_info *map, map_word d,
33 			     unsigned long addr)
34 {
35 	struct hyperbus_device *hbdev = map_to_hbdev(map);
36 	struct hyperbus_ctlr *ctlr = hbdev->ctlr;
37 
38 	ctlr->ops->write16(hbdev, addr, d.x[0]);
39 }
40 
41 static void hyperbus_copy_from(struct map_info *map, void *to,
42 			       unsigned long from, ssize_t len)
43 {
44 	struct hyperbus_device *hbdev = map_to_hbdev(map);
45 	struct hyperbus_ctlr *ctlr = hbdev->ctlr;
46 
47 	ctlr->ops->copy_from(hbdev, to, from, len);
48 }
49 
50 static void hyperbus_copy_to(struct map_info *map, unsigned long to,
51 			     const void *from, ssize_t len)
52 {
53 	struct hyperbus_device *hbdev = map_to_hbdev(map);
54 	struct hyperbus_ctlr *ctlr = hbdev->ctlr;
55 
56 	ctlr->ops->copy_to(hbdev, to, from, len);
57 }
58 
59 int hyperbus_register_device(struct hyperbus_device *hbdev)
60 {
61 	const struct hyperbus_ops *ops;
62 	struct hyperbus_ctlr *ctlr;
63 	struct device_node *np;
64 	struct map_info *map;
65 	struct resource res;
66 	struct device *dev;
67 	int ret;
68 
69 	if (!hbdev || !hbdev->np || !hbdev->ctlr || !hbdev->ctlr->dev) {
70 		pr_err("hyperbus: please fill all the necessary fields!\n");
71 		return -EINVAL;
72 	}
73 
74 	np = hbdev->np;
75 	ctlr = hbdev->ctlr;
76 	if (!of_device_is_compatible(np, "cypress,hyperflash"))
77 		return -ENODEV;
78 
79 	hbdev->memtype = HYPERFLASH;
80 
81 	ret = of_address_to_resource(np, 0, &res);
82 	if (ret)
83 		return ret;
84 
85 	dev = ctlr->dev;
86 	map = &hbdev->map;
87 	map->size = resource_size(&res);
88 	map->virt = devm_ioremap_resource(dev, &res);
89 	if (IS_ERR(map->virt))
90 		return PTR_ERR(map->virt);
91 
92 	map->name = dev_name(dev);
93 	map->bankwidth = 2;
94 	map->device_node = np;
95 
96 	simple_map_init(map);
97 	ops = ctlr->ops;
98 	if (ops) {
99 		if (ops->read16)
100 			map->read = hyperbus_read16;
101 		if (ops->write16)
102 			map->write = hyperbus_write16;
103 		if (ops->copy_to)
104 			map->copy_to = hyperbus_copy_to;
105 		if (ops->copy_from)
106 			map->copy_from = hyperbus_copy_from;
107 
108 		if (ops->calibrate && !ctlr->calibrated) {
109 			ret = ops->calibrate(hbdev);
110 			if (!ret) {
111 				dev_err(dev, "Calibration failed\n");
112 				return -ENODEV;
113 			}
114 			ctlr->calibrated = true;
115 		}
116 	}
117 
118 	hbdev->mtd = do_map_probe("cfi_probe", map);
119 	if (!hbdev->mtd) {
120 		dev_err(dev, "probing of hyperbus device failed\n");
121 		return -ENODEV;
122 	}
123 
124 	hbdev->mtd->dev.parent = dev;
125 	mtd_set_of_node(hbdev->mtd, np);
126 
127 	ret = mtd_device_register(hbdev->mtd, NULL, 0);
128 	if (ret) {
129 		dev_err(dev, "failed to register mtd device\n");
130 		map_destroy(hbdev->mtd);
131 		return ret;
132 	}
133 
134 	return 0;
135 }
136 EXPORT_SYMBOL_GPL(hyperbus_register_device);
137 
138 int hyperbus_unregister_device(struct hyperbus_device *hbdev)
139 {
140 	int ret = 0;
141 
142 	if (hbdev && hbdev->mtd) {
143 		ret = mtd_device_unregister(hbdev->mtd);
144 		map_destroy(hbdev->mtd);
145 	}
146 
147 	return ret;
148 }
149 EXPORT_SYMBOL_GPL(hyperbus_unregister_device);
150 
151 MODULE_DESCRIPTION("HyperBus Framework");
152 MODULE_LICENSE("GPL v2");
153 MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
154