xref: /openbmc/linux/drivers/video/fbdev/sbuslib.c (revision 842ed298)
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/kernel.h>
9 #include <linux/module.h>
10 #include <linux/string.h>
11 #include <linux/fb.h>
12 #include <linux/mm.h>
13 #include <linux/uaccess.h>
14 #include <linux/of_device.h>
15 
16 #include <asm/fbio.h>
17 
18 #include "sbuslib.h"
19 
20 void sbusfb_fill_var(struct fb_var_screeninfo *var, struct device_node *dp,
21 		     int bpp)
22 {
23 	memset(var, 0, sizeof(*var));
24 
25 	var->xres = of_getintprop_default(dp, "width", 1152);
26 	var->yres = of_getintprop_default(dp, "height", 900);
27 	var->xres_virtual = var->xres;
28 	var->yres_virtual = var->yres;
29 	var->bits_per_pixel = bpp;
30 }
31 
32 EXPORT_SYMBOL(sbusfb_fill_var);
33 
34 static unsigned long sbusfb_mmapsize(long size, unsigned long fbsize)
35 {
36 	if (size == SBUS_MMAP_EMPTY) return 0;
37 	if (size >= 0) return size;
38 	return fbsize * (-size);
39 }
40 
41 int sbusfb_mmap_helper(struct sbus_mmap_map *map,
42 		       unsigned long physbase,
43 		       unsigned long fbsize,
44 		       unsigned long iospace,
45 		       struct vm_area_struct *vma)
46 {
47 	unsigned int size, page, r, map_size;
48 	unsigned long map_offset = 0;
49 	unsigned long off;
50 	int i;
51 
52 	if (!(vma->vm_flags & (VM_SHARED | VM_MAYSHARE)))
53 		return -EINVAL;
54 
55 	size = vma->vm_end - vma->vm_start;
56 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
57 		return -EINVAL;
58 
59 	off = vma->vm_pgoff << PAGE_SHIFT;
60 
61 	/* VM_IO | VM_DONTEXPAND | VM_DONTDUMP are set by remap_pfn_range() */
62 
63 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
64 
65 	/* Each page, see which map applies */
66 	for (page = 0; page < size; ){
67 		map_size = 0;
68 		for (i = 0; map[i].size; i++)
69 			if (map[i].voff == off+page) {
70 				map_size = sbusfb_mmapsize(map[i].size, fbsize);
71 #ifdef __sparc_v9__
72 #define POFF_MASK	(PAGE_MASK|0x1UL)
73 #else
74 #define POFF_MASK	(PAGE_MASK)
75 #endif
76 				map_offset = (physbase + map[i].poff) & POFF_MASK;
77 				break;
78 			}
79 		if (!map_size) {
80 			page += PAGE_SIZE;
81 			continue;
82 		}
83 		if (page + map_size > size)
84 			map_size = size - page;
85 		r = io_remap_pfn_range(vma,
86 					vma->vm_start + page,
87 					MK_IOSPACE_PFN(iospace,
88 						map_offset >> PAGE_SHIFT),
89 					map_size,
90 					vma->vm_page_prot);
91 		if (r)
92 			return -EAGAIN;
93 		page += map_size;
94 	}
95 
96 	return 0;
97 }
98 EXPORT_SYMBOL(sbusfb_mmap_helper);
99 
100 int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
101 			struct fb_info *info,
102 			int type, int fb_depth, unsigned long fb_size)
103 {
104 	switch(cmd) {
105 	case FBIOGTYPE: {
106 		struct fbtype __user *f = (struct fbtype __user *) arg;
107 
108 		if (put_user(type, &f->fb_type) ||
109 		    put_user(info->var.yres, &f->fb_height) ||
110 		    put_user(info->var.xres, &f->fb_width) ||
111 		    put_user(fb_depth, &f->fb_depth) ||
112 		    put_user(0, &f->fb_cmsize) ||
113 		    put_user(fb_size, &f->fb_cmsize))
114 			return -EFAULT;
115 		return 0;
116 	}
117 	case FBIOPUTCMAP_SPARC: {
118 		struct fbcmap __user *c = (struct fbcmap __user *) arg;
119 		struct fb_cmap cmap;
120 		u16 red, green, blue;
121 		u8 red8, green8, blue8;
122 		unsigned char __user *ured;
123 		unsigned char __user *ugreen;
124 		unsigned char __user *ublue;
125 		unsigned int index, count, i;
126 
127 		if (get_user(index, &c->index) ||
128 		    get_user(count, &c->count) ||
129 		    get_user(ured, &c->red) ||
130 		    get_user(ugreen, &c->green) ||
131 		    get_user(ublue, &c->blue))
132 			return -EFAULT;
133 
134 		cmap.len = 1;
135 		cmap.red = &red;
136 		cmap.green = &green;
137 		cmap.blue = &blue;
138 		cmap.transp = NULL;
139 		for (i = 0; i < count; i++) {
140 			int err;
141 
142 			if (get_user(red8, &ured[i]) ||
143 			    get_user(green8, &ugreen[i]) ||
144 			    get_user(blue8, &ublue[i]))
145 				return -EFAULT;
146 
147 			red = red8 << 8;
148 			green = green8 << 8;
149 			blue = blue8 << 8;
150 
151 			cmap.start = index + i;
152 			err = fb_set_cmap(&cmap, info);
153 			if (err)
154 				return err;
155 		}
156 		return 0;
157 	}
158 	case FBIOGETCMAP_SPARC: {
159 		struct fbcmap __user *c = (struct fbcmap __user *) arg;
160 		unsigned char __user *ured;
161 		unsigned char __user *ugreen;
162 		unsigned char __user *ublue;
163 		struct fb_cmap *cmap = &info->cmap;
164 		unsigned int index, count, i;
165 		u8 red, green, blue;
166 
167 		if (get_user(index, &c->index) ||
168 		    get_user(count, &c->count) ||
169 		    get_user(ured, &c->red) ||
170 		    get_user(ugreen, &c->green) ||
171 		    get_user(ublue, &c->blue))
172 			return -EFAULT;
173 
174 		if (index > cmap->len || count > cmap->len - index)
175 			return -EINVAL;
176 
177 		for (i = 0; i < count; i++) {
178 			red = cmap->red[index + i] >> 8;
179 			green = cmap->green[index + i] >> 8;
180 			blue = cmap->blue[index + i] >> 8;
181 			if (put_user(red, &ured[i]) ||
182 			    put_user(green, &ugreen[i]) ||
183 			    put_user(blue, &ublue[i]))
184 				return -EFAULT;
185 		}
186 		return 0;
187 	}
188 	default:
189 		return -EINVAL;
190 	}
191 }
192 EXPORT_SYMBOL(sbusfb_ioctl_helper);
193 
194 #ifdef CONFIG_COMPAT
195 int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
196 {
197 	switch (cmd) {
198 	case FBIOGTYPE:
199 	case FBIOSATTR:
200 	case FBIOGATTR:
201 	case FBIOSVIDEO:
202 	case FBIOGVIDEO:
203 	case FBIOSCURSOR32:
204 	case FBIOGCURSOR32:	/* This is not implemented yet.
205 				   Later it should be converted... */
206 	case FBIOSCURPOS:
207 	case FBIOGCURPOS:
208 	case FBIOGCURMAX:
209 		return info->fbops->fb_ioctl(info, cmd, arg);
210 	case FBIOPUTCMAP32:
211 	case FBIOPUTCMAP_SPARC: {
212 		struct fbcmap32 c;
213 		struct fb_cmap cmap;
214 		u16 red, green, blue;
215 		u8 red8, green8, blue8;
216 		unsigned char __user *ured;
217 		unsigned char __user *ugreen;
218 		unsigned char __user *ublue;
219 		unsigned int i;
220 
221 		if (copy_from_user(&c, compat_ptr(arg), sizeof(c)))
222 			return -EFAULT;
223 		ured = compat_ptr(c.red);
224 		ugreen = compat_ptr(c.green);
225 		ublue = compat_ptr(c.blue);
226 
227 		cmap.len = 1;
228 		cmap.red = &red;
229 		cmap.green = &green;
230 		cmap.blue = &blue;
231 		cmap.transp = NULL;
232 		for (i = 0; i < c.count; i++) {
233 			int err;
234 
235 			if (get_user(red8, &ured[i]) ||
236 			    get_user(green8, &ugreen[i]) ||
237 			    get_user(blue8, &ublue[i]))
238 				return -EFAULT;
239 
240 			red = red8 << 8;
241 			green = green8 << 8;
242 			blue = blue8 << 8;
243 
244 			cmap.start = c.index + i;
245 			err = fb_set_cmap(&cmap, info);
246 			if (err)
247 				return err;
248 		}
249 		return 0;
250 	}
251 	case FBIOGETCMAP32: {
252 		struct fbcmap32 c;
253 		unsigned char __user *ured;
254 		unsigned char __user *ugreen;
255 		unsigned char __user *ublue;
256 		struct fb_cmap *cmap = &info->cmap;
257 		unsigned int index, i;
258 		u8 red, green, blue;
259 
260 		if (copy_from_user(&c, compat_ptr(arg), sizeof(c)))
261 			return -EFAULT;
262 		index = c.index;
263 		ured = compat_ptr(c.red);
264 		ugreen = compat_ptr(c.green);
265 		ublue = compat_ptr(c.blue);
266 
267 		if (index > cmap->len || c.count > cmap->len - index)
268 			return -EINVAL;
269 
270 		for (i = 0; i < c.count; i++) {
271 			red = cmap->red[index + i] >> 8;
272 			green = cmap->green[index + i] >> 8;
273 			blue = cmap->blue[index + i] >> 8;
274 			if (put_user(red, &ured[i]) ||
275 			    put_user(green, &ugreen[i]) ||
276 			    put_user(blue, &ublue[i]))
277 				return -EFAULT;
278 		}
279 		return 0;
280 	}
281 	default:
282 		return -ENOIOCTLCMD;
283 	}
284 }
285 EXPORT_SYMBOL(sbusfb_compat_ioctl);
286 #endif
287