1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  WonderMedia WM8505 Frame Buffer device driver
4 *
5 *  Copyright (C) 2010 Ed Spiridonov <edo.rus@gmail.com>
6 *    Based on vt8500lcdfb.c
7 */
8
9#include <linux/delay.h>
10#include <linux/dma-mapping.h>
11#include <linux/fb.h>
12#include <linux/errno.h>
13#include <linux/err.h>
14#include <linux/init.h>
15#include <linux/interrupt.h>
16#include <linux/io.h>
17#include <linux/kernel.h>
18#include <linux/memblock.h>
19#include <linux/mm.h>
20#include <linux/module.h>
21#include <linux/of.h>
22#include <linux/of_fdt.h>
23#include <linux/platform_device.h>
24#include <linux/slab.h>
25#include <linux/string.h>
26#include <linux/wait.h>
27#include <video/of_display_timing.h>
28
29#include "wm8505fb_regs.h"
30#include "wmt_ge_rops.h"
31
32#define DRIVER_NAME "wm8505-fb"
33
34#define to_wm8505fb_info(__info) container_of(__info, \
35						struct wm8505fb_info, fb)
36struct wm8505fb_info {
37	struct fb_info		fb;
38	void __iomem		*regbase;
39	unsigned int		contrast;
40};
41
42
43static int wm8505fb_init_hw(struct fb_info *info)
44{
45	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
46
47	int i;
48
49	/* I know the purpose only of few registers, so clear unknown */
50	for (i = 0; i < 0x200; i += 4)
51		writel(0, fbi->regbase + i);
52
53	/* Set frame buffer address */
54	writel(fbi->fb.fix.smem_start, fbi->regbase + WMT_GOVR_FBADDR);
55	writel(fbi->fb.fix.smem_start, fbi->regbase + WMT_GOVR_FBADDR1);
56
57	/*
58	 * Set in-memory picture format to RGB
59	 * 0x31C sets the correct color mode (RGB565) for WM8650
60	 * Bit 8+9 (0x300) are ignored on WM8505 as reserved
61	 */
62	writel(0x31c,		       fbi->regbase + WMT_GOVR_COLORSPACE);
63	writel(1,		       fbi->regbase + WMT_GOVR_COLORSPACE1);
64
65	/* Virtual buffer size */
66	writel(info->var.xres,	       fbi->regbase + WMT_GOVR_XRES);
67	writel(info->var.xres_virtual, fbi->regbase + WMT_GOVR_XRES_VIRTUAL);
68
69	/* black magic ;) */
70	writel(0xf,		       fbi->regbase + WMT_GOVR_FHI);
71	writel(4,		       fbi->regbase + WMT_GOVR_DVO_SET);
72	writel(1,		       fbi->regbase + WMT_GOVR_MIF_ENABLE);
73	writel(1,		       fbi->regbase + WMT_GOVR_REG_UPDATE);
74
75	return 0;
76}
77
78static int wm8505fb_set_timing(struct fb_info *info)
79{
80	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
81
82	int h_start = info->var.left_margin;
83	int h_end = h_start + info->var.xres;
84	int h_all = h_end + info->var.right_margin;
85	int h_sync = info->var.hsync_len;
86
87	int v_start = info->var.upper_margin;
88	int v_end = v_start + info->var.yres;
89	int v_all = v_end + info->var.lower_margin;
90	int v_sync = info->var.vsync_len;
91
92	writel(0, fbi->regbase + WMT_GOVR_TG);
93
94	writel(h_start, fbi->regbase + WMT_GOVR_TIMING_H_START);
95	writel(h_end,   fbi->regbase + WMT_GOVR_TIMING_H_END);
96	writel(h_all,   fbi->regbase + WMT_GOVR_TIMING_H_ALL);
97	writel(h_sync,  fbi->regbase + WMT_GOVR_TIMING_H_SYNC);
98
99	writel(v_start, fbi->regbase + WMT_GOVR_TIMING_V_START);
100	writel(v_end,   fbi->regbase + WMT_GOVR_TIMING_V_END);
101	writel(v_all,   fbi->regbase + WMT_GOVR_TIMING_V_ALL);
102	writel(v_sync,  fbi->regbase + WMT_GOVR_TIMING_V_SYNC);
103
104	writel(1, fbi->regbase + WMT_GOVR_TG);
105
106	return 0;
107}
108
109
110static int wm8505fb_set_par(struct fb_info *info)
111{
112	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
113
114	if (!fbi)
115		return -EINVAL;
116
117	if (info->var.bits_per_pixel == 32) {
118		info->var.red.offset = 16;
119		info->var.red.length = 8;
120		info->var.red.msb_right = 0;
121		info->var.green.offset = 8;
122		info->var.green.length = 8;
123		info->var.green.msb_right = 0;
124		info->var.blue.offset = 0;
125		info->var.blue.length = 8;
126		info->var.blue.msb_right = 0;
127		info->fix.visual = FB_VISUAL_TRUECOLOR;
128		info->fix.line_length = info->var.xres_virtual << 2;
129	} else if (info->var.bits_per_pixel == 16) {
130		info->var.red.offset = 11;
131		info->var.red.length = 5;
132		info->var.red.msb_right = 0;
133		info->var.green.offset = 5;
134		info->var.green.length = 6;
135		info->var.green.msb_right = 0;
136		info->var.blue.offset = 0;
137		info->var.blue.length = 5;
138		info->var.blue.msb_right = 0;
139		info->fix.visual = FB_VISUAL_TRUECOLOR;
140		info->fix.line_length = info->var.xres_virtual << 1;
141	}
142
143	wm8505fb_set_timing(info);
144
145	writel(fbi->contrast<<16 | fbi->contrast<<8 | fbi->contrast,
146		fbi->regbase + WMT_GOVR_CONTRAST);
147
148	return 0;
149}
150
151static ssize_t contrast_show(struct device *dev,
152			     struct device_attribute *attr, char *buf)
153{
154	struct fb_info *info = dev_get_drvdata(dev);
155	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
156
157	return sprintf(buf, "%u\n", fbi->contrast);
158}
159
160static ssize_t contrast_store(struct device *dev,
161			      struct device_attribute *attr,
162			      const char *buf, size_t count)
163{
164	struct fb_info *info = dev_get_drvdata(dev);
165	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
166	unsigned long tmp;
167
168	if (kstrtoul(buf, 10, &tmp) || (tmp > 0xff))
169		return -EINVAL;
170	fbi->contrast = tmp;
171
172	wm8505fb_set_par(info);
173
174	return count;
175}
176
177static DEVICE_ATTR_RW(contrast);
178
179static struct attribute *wm8505fb_attrs[] = {
180	&dev_attr_contrast.attr,
181	NULL,
182};
183ATTRIBUTE_GROUPS(wm8505fb);
184
185static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
186{
187	chan &= 0xffff;
188	chan >>= 16 - bf->length;
189	return chan << bf->offset;
190}
191
192static int wm8505fb_setcolreg(unsigned regno, unsigned red, unsigned green,
193			   unsigned blue, unsigned transp,
194			   struct fb_info *info) {
195	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
196	int ret = 1;
197	unsigned int val;
198	if (regno >= 256)
199		return -EINVAL;
200
201	if (info->var.grayscale)
202		red = green = blue =
203			(19595 * red + 38470 * green + 7471 * blue) >> 16;
204
205	switch (fbi->fb.fix.visual) {
206	case FB_VISUAL_TRUECOLOR:
207		if (regno < 16) {
208			u32 *pal = info->pseudo_palette;
209
210			val  = chan_to_field(red, &fbi->fb.var.red);
211			val |= chan_to_field(green, &fbi->fb.var.green);
212			val |= chan_to_field(blue, &fbi->fb.var.blue);
213
214			pal[regno] = val;
215			ret = 0;
216		}
217		break;
218	}
219
220	return ret;
221}
222
223static int wm8505fb_pan_display(struct fb_var_screeninfo *var,
224				struct fb_info *info)
225{
226	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
227
228	writel(var->xoffset, fbi->regbase + WMT_GOVR_XPAN);
229	writel(var->yoffset, fbi->regbase + WMT_GOVR_YPAN);
230	return 0;
231}
232
233static int wm8505fb_blank(int blank, struct fb_info *info)
234{
235	struct wm8505fb_info *fbi = to_wm8505fb_info(info);
236
237	switch (blank) {
238	case FB_BLANK_UNBLANK:
239		wm8505fb_set_timing(info);
240		break;
241	default:
242		writel(0,  fbi->regbase + WMT_GOVR_TIMING_V_SYNC);
243		break;
244	}
245
246	return 0;
247}
248
249static const struct fb_ops wm8505fb_ops = {
250	.owner		= THIS_MODULE,
251	.fb_set_par	= wm8505fb_set_par,
252	.fb_setcolreg	= wm8505fb_setcolreg,
253	.fb_fillrect	= wmt_ge_fillrect,
254	.fb_copyarea	= wmt_ge_copyarea,
255	.fb_imageblit	= sys_imageblit,
256	.fb_sync	= wmt_ge_sync,
257	.fb_pan_display	= wm8505fb_pan_display,
258	.fb_blank	= wm8505fb_blank,
259};
260
261static int wm8505fb_probe(struct platform_device *pdev)
262{
263	struct wm8505fb_info	*fbi;
264	struct display_timings *disp_timing;
265	void			*addr;
266	int ret;
267
268	struct fb_videomode	mode;
269	u32			bpp;
270	dma_addr_t fb_mem_phys;
271	unsigned long fb_mem_len;
272	void *fb_mem_virt;
273
274	fbi = devm_kzalloc(&pdev->dev, sizeof(struct wm8505fb_info) +
275			sizeof(u32) * 16, GFP_KERNEL);
276	if (!fbi)
277		return -ENOMEM;
278
279	strcpy(fbi->fb.fix.id, DRIVER_NAME);
280
281	fbi->fb.fix.type	= FB_TYPE_PACKED_PIXELS;
282	fbi->fb.fix.xpanstep	= 1;
283	fbi->fb.fix.ypanstep	= 1;
284	fbi->fb.fix.ywrapstep	= 0;
285	fbi->fb.fix.accel	= FB_ACCEL_NONE;
286
287	fbi->fb.fbops		= &wm8505fb_ops;
288	fbi->fb.flags		= FBINFO_HWACCEL_COPYAREA
289				| FBINFO_HWACCEL_FILLRECT
290				| FBINFO_HWACCEL_XPAN
291				| FBINFO_HWACCEL_YPAN
292				| FBINFO_VIRTFB
293				| FBINFO_PARTIAL_PAN_OK;
294	fbi->fb.node		= -1;
295
296	addr = fbi;
297	addr = addr + sizeof(struct wm8505fb_info);
298	fbi->fb.pseudo_palette	= addr;
299
300	fbi->regbase = devm_platform_ioremap_resource(pdev, 0);
301	if (IS_ERR(fbi->regbase))
302		return PTR_ERR(fbi->regbase);
303
304	disp_timing = of_get_display_timings(pdev->dev.of_node);
305	if (!disp_timing)
306		return -EINVAL;
307
308	ret = of_get_fb_videomode(pdev->dev.of_node, &mode, OF_USE_NATIVE_MODE);
309	if (ret)
310		return ret;
311
312	ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
313	if (ret)
314		return ret;
315
316	fb_videomode_to_var(&fbi->fb.var, &mode);
317
318	fbi->fb.var.nonstd		= 0;
319	fbi->fb.var.activate		= FB_ACTIVATE_NOW;
320
321	fbi->fb.var.height		= -1;
322	fbi->fb.var.width		= -1;
323
324	/* try allocating the framebuffer */
325	fb_mem_len = mode.xres * mode.yres * 2 * (bpp / 8);
326	fb_mem_virt = dmam_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
327				GFP_KERNEL);
328	if (!fb_mem_virt) {
329		pr_err("%s: Failed to allocate framebuffer\n", __func__);
330		return -ENOMEM;
331	}
332
333	fbi->fb.var.xres_virtual	= mode.xres;
334	fbi->fb.var.yres_virtual	= mode.yres * 2;
335	fbi->fb.var.bits_per_pixel	= bpp;
336
337	fbi->fb.fix.smem_start		= fb_mem_phys;
338	fbi->fb.fix.smem_len		= fb_mem_len;
339	fbi->fb.screen_buffer		= fb_mem_virt;
340	fbi->fb.screen_size		= fb_mem_len;
341
342	fbi->contrast = 0x10;
343	ret = wm8505fb_set_par(&fbi->fb);
344	if (ret) {
345		dev_err(&pdev->dev, "Failed to set parameters\n");
346		return ret;
347	}
348
349	if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
350		dev_err(&pdev->dev, "Failed to allocate color map\n");
351		return -ENOMEM;
352	}
353
354	wm8505fb_init_hw(&fbi->fb);
355
356	platform_set_drvdata(pdev, fbi);
357
358	ret = register_framebuffer(&fbi->fb);
359	if (ret < 0) {
360		dev_err(&pdev->dev,
361			"Failed to register framebuffer device: %d\n", ret);
362		if (fbi->fb.cmap.len)
363			fb_dealloc_cmap(&fbi->fb.cmap);
364		return ret;
365	}
366
367	fb_info(&fbi->fb, "%s frame buffer at 0x%lx-0x%lx\n",
368		fbi->fb.fix.id, fbi->fb.fix.smem_start,
369		fbi->fb.fix.smem_start + fbi->fb.fix.smem_len - 1);
370
371	return 0;
372}
373
374static void wm8505fb_remove(struct platform_device *pdev)
375{
376	struct wm8505fb_info *fbi = platform_get_drvdata(pdev);
377
378	unregister_framebuffer(&fbi->fb);
379
380	writel(0, fbi->regbase);
381
382	if (fbi->fb.cmap.len)
383		fb_dealloc_cmap(&fbi->fb.cmap);
384}
385
386static const struct of_device_id wmt_dt_ids[] = {
387	{ .compatible = "wm,wm8505-fb", },
388	{}
389};
390
391static struct platform_driver wm8505fb_driver = {
392	.probe		= wm8505fb_probe,
393	.remove_new	= wm8505fb_remove,
394	.driver		= {
395		.name	= DRIVER_NAME,
396		.of_match_table = wmt_dt_ids,
397		.dev_groups	= wm8505fb_groups,
398	},
399};
400
401module_platform_driver(wm8505fb_driver);
402
403MODULE_AUTHOR("Ed Spiridonov <edo.rus@gmail.com>");
404MODULE_DESCRIPTION("Framebuffer driver for WMT WM8505");
405MODULE_DEVICE_TABLE(of, wmt_dt_ids);
406