xref: /linux/drivers/video/fbdev/sbuslib.c (revision 22c55fb9eb92395d999b8404d73e58540d11bdd8)
1 // SPDX-License-Identifier: GPL-2.0
2 /* sbuslib.c: Helper library for SBUS framebuffer drivers.
3  *
4  * Copyright (C) 2003 David S. Miller (davem@redhat.com)
5  */
6 
7 #include <linux/compat.h>
8 #include <linux/export.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/string.h>
12 #include <linux/fb.h>
13 #include <linux/mm.h>
14 #include <linux/uaccess.h>
15 #include <linux/of.h>
16 
17 #include <asm/fbio.h>
18 
19 #include "sbuslib.h"
20 
21 void sbusfb_fill_var(struct fb_var_screeninfo *var, struct device_node *dp,
22 		     int bpp)
23 {
24 	memset(var, 0, sizeof(*var));
25 
26 	var->xres = of_getintprop_default(dp, "width", 1152);
27 	var->yres = of_getintprop_default(dp, "height", 900);
28 	var->xres_virtual = var->xres;
29 	var->yres_virtual = var->yres;
30 	var->bits_per_pixel = bpp;
31 }
32 
33 EXPORT_SYMBOL(sbusfb_fill_var);
34 
35 static unsigned long sbusfb_mmapsize(long size, unsigned long fbsize)
36 {
37 	if (size == SBUS_MMAP_EMPTY) return 0;
38 	if (size >= 0) return size;
39 	return fbsize * (-size);
40 }
41 
42 int sbusfb_mmap_helper(const struct sbus_mmap_map *map,
43 		       unsigned long physbase,
44 		       unsigned long fbsize,
45 		       unsigned long iospace,
46 		       struct vm_area_struct *vma)
47 {
48 	unsigned int size, page, r, map_size;
49 	unsigned long map_offset = 0;
50 	unsigned long off;
51 	int i;
52 
53 	if (!(vma->vm_flags & (VM_SHARED | VM_MAYSHARE)))
54 		return -EINVAL;
55 
56 	size = vma->vm_end - vma->vm_start;
57 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
58 		return -EINVAL;
59 
60 	off = vma->vm_pgoff << PAGE_SHIFT;
61 
62 	/* VM_IO | VM_DONTEXPAND | VM_DONTDUMP are set by remap_pfn_range() */
63 
64 	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
65 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
66 
67 	/* Each page, see which map applies */
68 	for (page = 0; page < size; ){
69 		map_size = 0;
70 		for (i = 0; map[i].size; i++)
71 			if (map[i].voff == off+page) {
72 				map_size = sbusfb_mmapsize(map[i].size, fbsize);
73 #ifdef __sparc_v9__
74 #define POFF_MASK	(PAGE_MASK|0x1UL)
75 #else
76 #define POFF_MASK	(PAGE_MASK)
77 #endif
78 				map_offset = (physbase + map[i].poff) & POFF_MASK;
79 				break;
80 			}
81 		if (!map_size) {
82 			page += PAGE_SIZE;
83 			continue;
84 		}
85 		if (page + map_size > size)
86 			map_size = size - page;
87 		r = io_remap_pfn_range(vma,
88 					vma->vm_start + page,
89 					MK_IOSPACE_PFN(iospace,
90 						map_offset >> PAGE_SHIFT),
91 					map_size,
92 					vma->vm_page_prot);
93 		if (r)
94 			return -EAGAIN;
95 		page += map_size;
96 	}
97 
98 	return 0;
99 }
100 EXPORT_SYMBOL(sbusfb_mmap_helper);
101 
102 int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
103 			struct fb_info *info,
104 			int type, int fb_depth, unsigned long fb_size)
105 {
106 	switch(cmd) {
107 	case FBIOGTYPE: {
108 		struct fbtype __user *f = (struct fbtype __user *) arg;
109 
110 		if (put_user(type, &f->fb_type) ||
111 		    put_user(info->var.yres, &f->fb_height) ||
112 		    put_user(info->var.xres, &f->fb_width) ||
113 		    put_user(fb_depth, &f->fb_depth) ||
114 		    put_user(0, &f->fb_cmsize) ||
115 		    put_user(fb_size, &f->fb_cmsize))
116 			return -EFAULT;
117 		return 0;
118 	}
119 	case FBIOPUTCMAP_SPARC: {
120 		struct fbcmap __user *c = (struct fbcmap __user *) arg;
121 		struct fb_cmap cmap;
122 		u16 red, green, blue;
123 		u8 red8, green8, blue8;
124 		unsigned char __user *ured;
125 		unsigned char __user *ugreen;
126 		unsigned char __user *ublue;
127 		unsigned int index, count, i;
128 
129 		if (get_user(index, &c->index) ||
130 		    get_user(count, &c->count) ||
131 		    get_user(ured, &c->red) ||
132 		    get_user(ugreen, &c->green) ||
133 		    get_user(ublue, &c->blue))
134 			return -EFAULT;
135 
136 		cmap.len = 1;
137 		cmap.red = &red;
138 		cmap.green = &green;
139 		cmap.blue = &blue;
140 		cmap.transp = NULL;
141 		for (i = 0; i < count; i++) {
142 			int err;
143 
144 			if (get_user(red8, &ured[i]) ||
145 			    get_user(green8, &ugreen[i]) ||
146 			    get_user(blue8, &ublue[i]))
147 				return -EFAULT;
148 
149 			red = red8 << 8;
150 			green = green8 << 8;
151 			blue = blue8 << 8;
152 
153 			cmap.start = index + i;
154 			err = fb_set_cmap(&cmap, info);
155 			if (err)
156 				return err;
157 		}
158 		return 0;
159 	}
160 	case FBIOGETCMAP_SPARC: {
161 		struct fbcmap __user *c = (struct fbcmap __user *) arg;
162 		unsigned char __user *ured;
163 		unsigned char __user *ugreen;
164 		unsigned char __user *ublue;
165 		struct fb_cmap *cmap = &info->cmap;
166 		unsigned int index, count, i;
167 		u8 red, green, blue;
168 
169 		if (get_user(index, &c->index) ||
170 		    get_user(count, &c->count) ||
171 		    get_user(ured, &c->red) ||
172 		    get_user(ugreen, &c->green) ||
173 		    get_user(ublue, &c->blue))
174 			return -EFAULT;
175 
176 		if (index > cmap->len || count > cmap->len - index)
177 			return -EINVAL;
178 
179 		for (i = 0; i < count; i++) {
180 			red = cmap->red[index + i] >> 8;
181 			green = cmap->green[index + i] >> 8;
182 			blue = cmap->blue[index + i] >> 8;
183 			if (put_user(red, &ured[i]) ||
184 			    put_user(green, &ugreen[i]) ||
185 			    put_user(blue, &ublue[i]))
186 				return -EFAULT;
187 		}
188 		return 0;
189 	}
190 	default:
191 		return -EINVAL;
192 	}
193 }
194 EXPORT_SYMBOL(sbusfb_ioctl_helper);
195 
196 #ifdef CONFIG_COMPAT
197 int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
198 {
199 	switch (cmd) {
200 	case FBIOGTYPE:
201 	case FBIOSATTR:
202 	case FBIOGATTR:
203 	case FBIOSVIDEO:
204 	case FBIOGVIDEO:
205 	case FBIOSCURSOR32:
206 	case FBIOGCURSOR32:	/* This is not implemented yet.
207 				   Later it should be converted... */
208 	case FBIOSCURPOS:
209 	case FBIOGCURPOS:
210 	case FBIOGCURMAX:
211 		return info->fbops->fb_ioctl(info, cmd, arg);
212 	case FBIOPUTCMAP32:
213 	case FBIOPUTCMAP_SPARC: {
214 		struct fbcmap32 c;
215 		struct fb_cmap cmap;
216 		u16 red, green, blue;
217 		u8 red8, green8, blue8;
218 		unsigned char __user *ured;
219 		unsigned char __user *ugreen;
220 		unsigned char __user *ublue;
221 		unsigned int i;
222 
223 		if (copy_from_user(&c, compat_ptr(arg), sizeof(c)))
224 			return -EFAULT;
225 		ured = compat_ptr(c.red);
226 		ugreen = compat_ptr(c.green);
227 		ublue = compat_ptr(c.blue);
228 
229 		cmap.len = 1;
230 		cmap.red = &red;
231 		cmap.green = &green;
232 		cmap.blue = &blue;
233 		cmap.transp = NULL;
234 		for (i = 0; i < c.count; i++) {
235 			int err;
236 
237 			if (get_user(red8, &ured[i]) ||
238 			    get_user(green8, &ugreen[i]) ||
239 			    get_user(blue8, &ublue[i]))
240 				return -EFAULT;
241 
242 			red = red8 << 8;
243 			green = green8 << 8;
244 			blue = blue8 << 8;
245 
246 			cmap.start = c.index + i;
247 			err = fb_set_cmap(&cmap, info);
248 			if (err)
249 				return err;
250 		}
251 		return 0;
252 	}
253 	case FBIOGETCMAP32: {
254 		struct fbcmap32 c;
255 		unsigned char __user *ured;
256 		unsigned char __user *ugreen;
257 		unsigned char __user *ublue;
258 		struct fb_cmap *cmap = &info->cmap;
259 		unsigned int index, i;
260 		u8 red, green, blue;
261 
262 		if (copy_from_user(&c, compat_ptr(arg), sizeof(c)))
263 			return -EFAULT;
264 		index = c.index;
265 		ured = compat_ptr(c.red);
266 		ugreen = compat_ptr(c.green);
267 		ublue = compat_ptr(c.blue);
268 
269 		if (index > cmap->len || c.count > cmap->len - index)
270 			return -EINVAL;
271 
272 		for (i = 0; i < c.count; i++) {
273 			red = cmap->red[index + i] >> 8;
274 			green = cmap->green[index + i] >> 8;
275 			blue = cmap->blue[index + i] >> 8;
276 			if (put_user(red, &ured[i]) ||
277 			    put_user(green, &ugreen[i]) ||
278 			    put_user(blue, &ublue[i]))
279 				return -EFAULT;
280 		}
281 		return 0;
282 	}
283 	default:
284 		return -ENOIOCTLCMD;
285 	}
286 }
287 EXPORT_SYMBOL(sbusfb_compat_ioctl);
288 #endif
289