xref: /openbmc/linux/drivers/video/fbdev/wm8505fb.c (revision 293d5b43)
1 /*
2  *  WonderMedia WM8505 Frame Buffer device driver
3  *
4  *  Copyright (C) 2010 Ed Spiridonov <edo.rus@gmail.com>
5  *    Based on vt8500lcdfb.c
6  *
7  * This software is licensed under the terms of the GNU General Public
8  * License version 2, as published by the Free Software Foundation, and
9  * may be copied, distributed, and modified under those terms.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/delay.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/fb.h>
20 #include <linux/errno.h>
21 #include <linux/err.h>
22 #include <linux/init.h>
23 #include <linux/interrupt.h>
24 #include <linux/io.h>
25 #include <linux/kernel.h>
26 #include <linux/memblock.h>
27 #include <linux/mm.h>
28 #include <linux/module.h>
29 #include <linux/of.h>
30 #include <linux/of_fdt.h>
31 #include <linux/platform_device.h>
32 #include <linux/slab.h>
33 #include <linux/string.h>
34 #include <linux/wait.h>
35 #include <video/of_display_timing.h>
36 
37 #include "wm8505fb_regs.h"
38 #include "wmt_ge_rops.h"
39 
40 #define DRIVER_NAME "wm8505-fb"
41 
42 #define to_wm8505fb_info(__info) container_of(__info, \
43 						struct wm8505fb_info, fb)
44 struct wm8505fb_info {
45 	struct fb_info		fb;
46 	void __iomem		*regbase;
47 	unsigned int		contrast;
48 };
49 
50 
51 static int wm8505fb_init_hw(struct fb_info *info)
52 {
53 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
54 
55 	int i;
56 
57 	/* I know the purpose only of few registers, so clear unknown */
58 	for (i = 0; i < 0x200; i += 4)
59 		writel(0, fbi->regbase + i);
60 
61 	/* Set frame buffer address */
62 	writel(fbi->fb.fix.smem_start, fbi->regbase + WMT_GOVR_FBADDR);
63 	writel(fbi->fb.fix.smem_start, fbi->regbase + WMT_GOVR_FBADDR1);
64 
65 	/*
66 	 * Set in-memory picture format to RGB
67 	 * 0x31C sets the correct color mode (RGB565) for WM8650
68 	 * Bit 8+9 (0x300) are ignored on WM8505 as reserved
69 	 */
70 	writel(0x31c,		       fbi->regbase + WMT_GOVR_COLORSPACE);
71 	writel(1,		       fbi->regbase + WMT_GOVR_COLORSPACE1);
72 
73 	/* Virtual buffer size */
74 	writel(info->var.xres,	       fbi->regbase + WMT_GOVR_XRES);
75 	writel(info->var.xres_virtual, fbi->regbase + WMT_GOVR_XRES_VIRTUAL);
76 
77 	/* black magic ;) */
78 	writel(0xf,		       fbi->regbase + WMT_GOVR_FHI);
79 	writel(4,		       fbi->regbase + WMT_GOVR_DVO_SET);
80 	writel(1,		       fbi->regbase + WMT_GOVR_MIF_ENABLE);
81 	writel(1,		       fbi->regbase + WMT_GOVR_REG_UPDATE);
82 
83 	return 0;
84 }
85 
86 static int wm8505fb_set_timing(struct fb_info *info)
87 {
88 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
89 
90 	int h_start = info->var.left_margin;
91 	int h_end = h_start + info->var.xres;
92 	int h_all = h_end + info->var.right_margin;
93 	int h_sync = info->var.hsync_len;
94 
95 	int v_start = info->var.upper_margin;
96 	int v_end = v_start + info->var.yres;
97 	int v_all = v_end + info->var.lower_margin;
98 	int v_sync = info->var.vsync_len;
99 
100 	writel(0, fbi->regbase + WMT_GOVR_TG);
101 
102 	writel(h_start, fbi->regbase + WMT_GOVR_TIMING_H_START);
103 	writel(h_end,   fbi->regbase + WMT_GOVR_TIMING_H_END);
104 	writel(h_all,   fbi->regbase + WMT_GOVR_TIMING_H_ALL);
105 	writel(h_sync,  fbi->regbase + WMT_GOVR_TIMING_H_SYNC);
106 
107 	writel(v_start, fbi->regbase + WMT_GOVR_TIMING_V_START);
108 	writel(v_end,   fbi->regbase + WMT_GOVR_TIMING_V_END);
109 	writel(v_all,   fbi->regbase + WMT_GOVR_TIMING_V_ALL);
110 	writel(v_sync,  fbi->regbase + WMT_GOVR_TIMING_V_SYNC);
111 
112 	writel(1, fbi->regbase + WMT_GOVR_TG);
113 
114 	return 0;
115 }
116 
117 
118 static int wm8505fb_set_par(struct fb_info *info)
119 {
120 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
121 
122 	if (!fbi)
123 		return -EINVAL;
124 
125 	if (info->var.bits_per_pixel == 32) {
126 		info->var.red.offset = 16;
127 		info->var.red.length = 8;
128 		info->var.red.msb_right = 0;
129 		info->var.green.offset = 8;
130 		info->var.green.length = 8;
131 		info->var.green.msb_right = 0;
132 		info->var.blue.offset = 0;
133 		info->var.blue.length = 8;
134 		info->var.blue.msb_right = 0;
135 		info->fix.visual = FB_VISUAL_TRUECOLOR;
136 		info->fix.line_length = info->var.xres_virtual << 2;
137 	} else if (info->var.bits_per_pixel == 16) {
138 		info->var.red.offset = 11;
139 		info->var.red.length = 5;
140 		info->var.red.msb_right = 0;
141 		info->var.green.offset = 5;
142 		info->var.green.length = 6;
143 		info->var.green.msb_right = 0;
144 		info->var.blue.offset = 0;
145 		info->var.blue.length = 5;
146 		info->var.blue.msb_right = 0;
147 		info->fix.visual = FB_VISUAL_TRUECOLOR;
148 		info->fix.line_length = info->var.xres_virtual << 1;
149 	}
150 
151 	wm8505fb_set_timing(info);
152 
153 	writel(fbi->contrast<<16 | fbi->contrast<<8 | fbi->contrast,
154 		fbi->regbase + WMT_GOVR_CONTRAST);
155 
156 	return 0;
157 }
158 
159 static ssize_t contrast_show(struct device *dev,
160 			     struct device_attribute *attr, char *buf)
161 {
162 	struct fb_info *info = dev_get_drvdata(dev);
163 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
164 
165 	return sprintf(buf, "%u\n", fbi->contrast);
166 }
167 
168 static ssize_t contrast_store(struct device *dev,
169 			      struct device_attribute *attr,
170 			      const char *buf, size_t count)
171 {
172 	struct fb_info *info = dev_get_drvdata(dev);
173 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
174 	unsigned long tmp;
175 
176 	if (kstrtoul(buf, 10, &tmp) || (tmp > 0xff))
177 		return -EINVAL;
178 	fbi->contrast = tmp;
179 
180 	wm8505fb_set_par(info);
181 
182 	return count;
183 }
184 
185 static DEVICE_ATTR(contrast, 0644, contrast_show, contrast_store);
186 
187 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
188 {
189 	chan &= 0xffff;
190 	chan >>= 16 - bf->length;
191 	return chan << bf->offset;
192 }
193 
194 static int wm8505fb_setcolreg(unsigned regno, unsigned red, unsigned green,
195 			   unsigned blue, unsigned transp,
196 			   struct fb_info *info) {
197 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
198 	int ret = 1;
199 	unsigned int val;
200 	if (regno >= 256)
201 		return -EINVAL;
202 
203 	if (info->var.grayscale)
204 		red = green = blue =
205 			(19595 * red + 38470 * green + 7471 * blue) >> 16;
206 
207 	switch (fbi->fb.fix.visual) {
208 	case FB_VISUAL_TRUECOLOR:
209 		if (regno < 16) {
210 			u32 *pal = info->pseudo_palette;
211 
212 			val  = chan_to_field(red, &fbi->fb.var.red);
213 			val |= chan_to_field(green, &fbi->fb.var.green);
214 			val |= chan_to_field(blue, &fbi->fb.var.blue);
215 
216 			pal[regno] = val;
217 			ret = 0;
218 		}
219 		break;
220 	}
221 
222 	return ret;
223 }
224 
225 static int wm8505fb_pan_display(struct fb_var_screeninfo *var,
226 				struct fb_info *info)
227 {
228 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
229 
230 	writel(var->xoffset, fbi->regbase + WMT_GOVR_XPAN);
231 	writel(var->yoffset, fbi->regbase + WMT_GOVR_YPAN);
232 	return 0;
233 }
234 
235 static int wm8505fb_blank(int blank, struct fb_info *info)
236 {
237 	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
238 
239 	switch (blank) {
240 	case FB_BLANK_UNBLANK:
241 		wm8505fb_set_timing(info);
242 		break;
243 	default:
244 		writel(0,  fbi->regbase + WMT_GOVR_TIMING_V_SYNC);
245 		break;
246 	}
247 
248 	return 0;
249 }
250 
251 static struct fb_ops wm8505fb_ops = {
252 	.owner		= THIS_MODULE,
253 	.fb_set_par	= wm8505fb_set_par,
254 	.fb_setcolreg	= wm8505fb_setcolreg,
255 	.fb_fillrect	= wmt_ge_fillrect,
256 	.fb_copyarea	= wmt_ge_copyarea,
257 	.fb_imageblit	= sys_imageblit,
258 	.fb_sync	= wmt_ge_sync,
259 	.fb_pan_display	= wm8505fb_pan_display,
260 	.fb_blank	= wm8505fb_blank,
261 };
262 
263 static int wm8505fb_probe(struct platform_device *pdev)
264 {
265 	struct wm8505fb_info	*fbi;
266 	struct resource	*res;
267 	struct display_timings *disp_timing;
268 	void			*addr;
269 	int ret;
270 
271 	struct fb_videomode	mode;
272 	u32			bpp;
273 	dma_addr_t fb_mem_phys;
274 	unsigned long fb_mem_len;
275 	void *fb_mem_virt;
276 
277 	fbi = devm_kzalloc(&pdev->dev, sizeof(struct wm8505fb_info) +
278 			sizeof(u32) * 16, GFP_KERNEL);
279 	if (!fbi) {
280 		dev_err(&pdev->dev, "Failed to initialize framebuffer device\n");
281 		return -ENOMEM;
282 	}
283 
284 	strcpy(fbi->fb.fix.id, DRIVER_NAME);
285 
286 	fbi->fb.fix.type	= FB_TYPE_PACKED_PIXELS;
287 	fbi->fb.fix.xpanstep	= 1;
288 	fbi->fb.fix.ypanstep	= 1;
289 	fbi->fb.fix.ywrapstep	= 0;
290 	fbi->fb.fix.accel	= FB_ACCEL_NONE;
291 
292 	fbi->fb.fbops		= &wm8505fb_ops;
293 	fbi->fb.flags		= FBINFO_DEFAULT
294 				| FBINFO_HWACCEL_COPYAREA
295 				| FBINFO_HWACCEL_FILLRECT
296 				| FBINFO_HWACCEL_XPAN
297 				| FBINFO_HWACCEL_YPAN
298 				| FBINFO_VIRTFB
299 				| FBINFO_PARTIAL_PAN_OK;
300 	fbi->fb.node		= -1;
301 
302 	addr = fbi;
303 	addr = addr + sizeof(struct wm8505fb_info);
304 	fbi->fb.pseudo_palette	= addr;
305 
306 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
307 	fbi->regbase = devm_ioremap_resource(&pdev->dev, res);
308 	if (IS_ERR(fbi->regbase))
309 		return PTR_ERR(fbi->regbase);
310 
311 	disp_timing = of_get_display_timings(pdev->dev.of_node);
312 	if (!disp_timing)
313 		return -EINVAL;
314 
315 	ret = of_get_fb_videomode(pdev->dev.of_node, &mode, OF_USE_NATIVE_MODE);
316 	if (ret)
317 		return ret;
318 
319 	ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
320 	if (ret)
321 		return ret;
322 
323 	fb_videomode_to_var(&fbi->fb.var, &mode);
324 
325 	fbi->fb.var.nonstd		= 0;
326 	fbi->fb.var.activate		= FB_ACTIVATE_NOW;
327 
328 	fbi->fb.var.height		= -1;
329 	fbi->fb.var.width		= -1;
330 
331 	/* try allocating the framebuffer */
332 	fb_mem_len = mode.xres * mode.yres * 2 * (bpp / 8);
333 	fb_mem_virt = dmam_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
334 				GFP_KERNEL);
335 	if (!fb_mem_virt) {
336 		pr_err("%s: Failed to allocate framebuffer\n", __func__);
337 		return -ENOMEM;
338 	}
339 
340 	fbi->fb.var.xres_virtual	= mode.xres;
341 	fbi->fb.var.yres_virtual	= mode.yres * 2;
342 	fbi->fb.var.bits_per_pixel	= bpp;
343 
344 	fbi->fb.fix.smem_start		= fb_mem_phys;
345 	fbi->fb.fix.smem_len		= fb_mem_len;
346 	fbi->fb.screen_base		= fb_mem_virt;
347 	fbi->fb.screen_size		= fb_mem_len;
348 
349 	fbi->contrast = 0x10;
350 	ret = wm8505fb_set_par(&fbi->fb);
351 	if (ret) {
352 		dev_err(&pdev->dev, "Failed to set parameters\n");
353 		return ret;
354 	}
355 
356 	if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
357 		dev_err(&pdev->dev, "Failed to allocate color map\n");
358 		return -ENOMEM;
359 	}
360 
361 	wm8505fb_init_hw(&fbi->fb);
362 
363 	platform_set_drvdata(pdev, fbi);
364 
365 	ret = register_framebuffer(&fbi->fb);
366 	if (ret < 0) {
367 		dev_err(&pdev->dev,
368 			"Failed to register framebuffer device: %d\n", ret);
369 		if (fbi->fb.cmap.len)
370 			fb_dealloc_cmap(&fbi->fb.cmap);
371 		return ret;
372 	}
373 
374 	ret = device_create_file(&pdev->dev, &dev_attr_contrast);
375 	if (ret < 0)
376 		fb_warn(&fbi->fb, "failed to register attributes (%d)\n", ret);
377 
378 	fb_info(&fbi->fb, "%s frame buffer at 0x%lx-0x%lx\n",
379 		fbi->fb.fix.id, fbi->fb.fix.smem_start,
380 		fbi->fb.fix.smem_start + fbi->fb.fix.smem_len - 1);
381 
382 	return 0;
383 }
384 
385 static int wm8505fb_remove(struct platform_device *pdev)
386 {
387 	struct wm8505fb_info *fbi = platform_get_drvdata(pdev);
388 
389 	device_remove_file(&pdev->dev, &dev_attr_contrast);
390 
391 	unregister_framebuffer(&fbi->fb);
392 
393 	writel(0, fbi->regbase);
394 
395 	if (fbi->fb.cmap.len)
396 		fb_dealloc_cmap(&fbi->fb.cmap);
397 
398 	return 0;
399 }
400 
401 static const struct of_device_id wmt_dt_ids[] = {
402 	{ .compatible = "wm,wm8505-fb", },
403 	{}
404 };
405 
406 static struct platform_driver wm8505fb_driver = {
407 	.probe		= wm8505fb_probe,
408 	.remove		= wm8505fb_remove,
409 	.driver		= {
410 		.name	= DRIVER_NAME,
411 		.of_match_table = wmt_dt_ids,
412 	},
413 };
414 
415 module_platform_driver(wm8505fb_driver);
416 
417 MODULE_AUTHOR("Ed Spiridonov <edo.rus@gmail.com>");
418 MODULE_DESCRIPTION("Framebuffer driver for WMT WM8505");
419 MODULE_LICENSE("GPL v2");
420 MODULE_DEVICE_TABLE(of, wmt_dt_ids);
421