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)
44struct wm8505fb_info {
45	struct fb_info		fb;
46	void __iomem		*regbase;
47	unsigned int		contrast;
48};
49
50
51static 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
86static 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
118static 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
159static 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
168static 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
185static DEVICE_ATTR(contrast, 0644, contrast_show, contrast_store);
186
187static 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
194static 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
225static 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
235static 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
251static 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
263static 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
385static 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
401static const struct of_device_id wmt_dt_ids[] = {
402	{ .compatible = "wm,wm8505-fb", },
403	{}
404};
405
406static 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
415module_platform_driver(wm8505fb_driver);
416
417MODULE_AUTHOR("Ed Spiridonov <edo.rus@gmail.com>");
418MODULE_DESCRIPTION("Framebuffer driver for WMT WM8505");
419MODULE_LICENSE("GPL v2");
420MODULE_DEVICE_TABLE(of, wmt_dt_ids);
421