xref: /linux/drivers/video/fbdev/atmel_lcdfb.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  *  Driver for AT91/AT32 LCD Controller
3  *
4  *  Copyright (C) 2007 Atmel Corporation
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file COPYING in the main directory of this archive for
8  * more details.
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/platform_device.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/interrupt.h>
15 #include <linux/clk.h>
16 #include <linux/fb.h>
17 #include <linux/init.h>
18 #include <linux/delay.h>
19 #include <linux/backlight.h>
20 #include <linux/gfp.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/of_gpio.h>
25 #include <video/of_display_timing.h>
26 #include <linux/regulator/consumer.h>
27 #include <video/videomode.h>
28 
29 #include <asm/gpio.h>
30 
31 #include <video/atmel_lcdc.h>
32 
33 struct atmel_lcdfb_config {
34 	bool have_alt_pixclock;
35 	bool have_hozval;
36 	bool have_intensity_bit;
37 };
38 
39  /* LCD Controller info data structure, stored in device platform_data */
40 struct atmel_lcdfb_info {
41 	spinlock_t		lock;
42 	struct fb_info		*info;
43 	void __iomem		*mmio;
44 	int			irq_base;
45 	struct work_struct	task;
46 
47 	unsigned int		smem_len;
48 	struct platform_device	*pdev;
49 	struct clk		*bus_clk;
50 	struct clk		*lcdc_clk;
51 
52 	struct backlight_device	*backlight;
53 	u8			bl_power;
54 	u8			saved_lcdcon;
55 
56 	u32			pseudo_palette[16];
57 	bool			have_intensity_bit;
58 
59 	struct atmel_lcdfb_pdata pdata;
60 
61 	struct atmel_lcdfb_config *config;
62 	struct regulator	*reg_lcd;
63 };
64 
65 struct atmel_lcdfb_power_ctrl_gpio {
66 	int gpio;
67 	int active_low;
68 
69 	struct list_head list;
70 };
71 
72 #define lcdc_readl(sinfo, reg)		__raw_readl((sinfo)->mmio+(reg))
73 #define lcdc_writel(sinfo, reg, val)	__raw_writel((val), (sinfo)->mmio+(reg))
74 
75 /* configurable parameters */
76 #define ATMEL_LCDC_CVAL_DEFAULT		0xc8
77 #define ATMEL_LCDC_DMA_BURST_LEN	8	/* words */
78 #define ATMEL_LCDC_FIFO_SIZE		512	/* words */
79 
80 static struct atmel_lcdfb_config at91sam9261_config = {
81 	.have_hozval		= true,
82 	.have_intensity_bit	= true,
83 };
84 
85 static struct atmel_lcdfb_config at91sam9263_config = {
86 	.have_intensity_bit	= true,
87 };
88 
89 static struct atmel_lcdfb_config at91sam9g10_config = {
90 	.have_hozval		= true,
91 };
92 
93 static struct atmel_lcdfb_config at91sam9g45_config = {
94 	.have_alt_pixclock	= true,
95 };
96 
97 static struct atmel_lcdfb_config at91sam9g45es_config = {
98 };
99 
100 static struct atmel_lcdfb_config at91sam9rl_config = {
101 	.have_intensity_bit	= true,
102 };
103 
104 static struct atmel_lcdfb_config at32ap_config = {
105 	.have_hozval		= true,
106 };
107 
108 static const struct platform_device_id atmel_lcdfb_devtypes[] = {
109 	{
110 		.name = "at91sam9261-lcdfb",
111 		.driver_data = (unsigned long)&at91sam9261_config,
112 	}, {
113 		.name = "at91sam9263-lcdfb",
114 		.driver_data = (unsigned long)&at91sam9263_config,
115 	}, {
116 		.name = "at91sam9g10-lcdfb",
117 		.driver_data = (unsigned long)&at91sam9g10_config,
118 	}, {
119 		.name = "at91sam9g45-lcdfb",
120 		.driver_data = (unsigned long)&at91sam9g45_config,
121 	}, {
122 		.name = "at91sam9g45es-lcdfb",
123 		.driver_data = (unsigned long)&at91sam9g45es_config,
124 	}, {
125 		.name = "at91sam9rl-lcdfb",
126 		.driver_data = (unsigned long)&at91sam9rl_config,
127 	}, {
128 		.name = "at32ap-lcdfb",
129 		.driver_data = (unsigned long)&at32ap_config,
130 	}, {
131 		/* terminator */
132 	}
133 };
134 MODULE_DEVICE_TABLE(platform, atmel_lcdfb_devtypes);
135 
136 static struct atmel_lcdfb_config *
137 atmel_lcdfb_get_config(struct platform_device *pdev)
138 {
139 	unsigned long data;
140 
141 	data = platform_get_device_id(pdev)->driver_data;
142 
143 	return (struct atmel_lcdfb_config *)data;
144 }
145 
146 #if defined(CONFIG_ARCH_AT91)
147 #define	ATMEL_LCDFB_FBINFO_DEFAULT	(FBINFO_DEFAULT \
148 					 | FBINFO_PARTIAL_PAN_OK \
149 					 | FBINFO_HWACCEL_YPAN)
150 
151 static inline void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
152 					struct fb_var_screeninfo *var,
153 					struct fb_info *info)
154 {
155 
156 }
157 #elif defined(CONFIG_AVR32)
158 #define	ATMEL_LCDFB_FBINFO_DEFAULT	(FBINFO_DEFAULT \
159 					| FBINFO_PARTIAL_PAN_OK \
160 					| FBINFO_HWACCEL_XPAN \
161 					| FBINFO_HWACCEL_YPAN)
162 
163 static void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
164 				     struct fb_var_screeninfo *var,
165 				     struct fb_info *info)
166 {
167 	u32 dma2dcfg;
168 	u32 pixeloff;
169 
170 	pixeloff = (var->xoffset * info->var.bits_per_pixel) & 0x1f;
171 
172 	dma2dcfg = (info->var.xres_virtual - info->var.xres)
173 		 * info->var.bits_per_pixel / 8;
174 	dma2dcfg |= pixeloff << ATMEL_LCDC_PIXELOFF_OFFSET;
175 	lcdc_writel(sinfo, ATMEL_LCDC_DMA2DCFG, dma2dcfg);
176 
177 	/* Update configuration */
178 	lcdc_writel(sinfo, ATMEL_LCDC_DMACON,
179 		    lcdc_readl(sinfo, ATMEL_LCDC_DMACON)
180 		    | ATMEL_LCDC_DMAUPDT);
181 }
182 #endif
183 
184 static u32 contrast_ctr = ATMEL_LCDC_PS_DIV8
185 		| ATMEL_LCDC_POL_POSITIVE
186 		| ATMEL_LCDC_ENA_PWMENABLE;
187 
188 #ifdef CONFIG_BACKLIGHT_ATMEL_LCDC
189 
190 /* some bl->props field just changed */
191 static int atmel_bl_update_status(struct backlight_device *bl)
192 {
193 	struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
194 	int			power = sinfo->bl_power;
195 	int			brightness = bl->props.brightness;
196 
197 	/* REVISIT there may be a meaningful difference between
198 	 * fb_blank and power ... there seem to be some cases
199 	 * this doesn't handle correctly.
200 	 */
201 	if (bl->props.fb_blank != sinfo->bl_power)
202 		power = bl->props.fb_blank;
203 	else if (bl->props.power != sinfo->bl_power)
204 		power = bl->props.power;
205 
206 	if (brightness < 0 && power == FB_BLANK_UNBLANK)
207 		brightness = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
208 	else if (power != FB_BLANK_UNBLANK)
209 		brightness = 0;
210 
211 	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, brightness);
212 	if (contrast_ctr & ATMEL_LCDC_POL_POSITIVE)
213 		lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
214 			brightness ? contrast_ctr : 0);
215 	else
216 		lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
217 
218 	bl->props.fb_blank = bl->props.power = sinfo->bl_power = power;
219 
220 	return 0;
221 }
222 
223 static int atmel_bl_get_brightness(struct backlight_device *bl)
224 {
225 	struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
226 
227 	return lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
228 }
229 
230 static const struct backlight_ops atmel_lcdc_bl_ops = {
231 	.update_status = atmel_bl_update_status,
232 	.get_brightness = atmel_bl_get_brightness,
233 };
234 
235 static void init_backlight(struct atmel_lcdfb_info *sinfo)
236 {
237 	struct backlight_properties props;
238 	struct backlight_device	*bl;
239 
240 	sinfo->bl_power = FB_BLANK_UNBLANK;
241 
242 	if (sinfo->backlight)
243 		return;
244 
245 	memset(&props, 0, sizeof(struct backlight_properties));
246 	props.type = BACKLIGHT_RAW;
247 	props.max_brightness = 0xff;
248 	bl = backlight_device_register("backlight", &sinfo->pdev->dev, sinfo,
249 				       &atmel_lcdc_bl_ops, &props);
250 	if (IS_ERR(bl)) {
251 		dev_err(&sinfo->pdev->dev, "error %ld on backlight register\n",
252 				PTR_ERR(bl));
253 		return;
254 	}
255 	sinfo->backlight = bl;
256 
257 	bl->props.power = FB_BLANK_UNBLANK;
258 	bl->props.fb_blank = FB_BLANK_UNBLANK;
259 	bl->props.brightness = atmel_bl_get_brightness(bl);
260 }
261 
262 static void exit_backlight(struct atmel_lcdfb_info *sinfo)
263 {
264 	if (!sinfo->backlight)
265 		return;
266 
267 	if (sinfo->backlight->ops) {
268 		sinfo->backlight->props.power = FB_BLANK_POWERDOWN;
269 		sinfo->backlight->ops->update_status(sinfo->backlight);
270 	}
271 	backlight_device_unregister(sinfo->backlight);
272 }
273 
274 #else
275 
276 static void init_backlight(struct atmel_lcdfb_info *sinfo)
277 {
278 	dev_warn(&sinfo->pdev->dev, "backlight control is not available\n");
279 }
280 
281 static void exit_backlight(struct atmel_lcdfb_info *sinfo)
282 {
283 }
284 
285 #endif
286 
287 static void init_contrast(struct atmel_lcdfb_info *sinfo)
288 {
289 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
290 
291 	/* contrast pwm can be 'inverted' */
292 	if (pdata->lcdcon_pol_negative)
293 		contrast_ctr &= ~(ATMEL_LCDC_POL_POSITIVE);
294 
295 	/* have some default contrast/backlight settings */
296 	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
297 	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, ATMEL_LCDC_CVAL_DEFAULT);
298 
299 	if (pdata->lcdcon_is_backlight)
300 		init_backlight(sinfo);
301 }
302 
303 static inline void atmel_lcdfb_power_control(struct atmel_lcdfb_info *sinfo, int on)
304 {
305 	int ret;
306 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
307 
308 	if (pdata->atmel_lcdfb_power_control)
309 		pdata->atmel_lcdfb_power_control(pdata, on);
310 	else if (sinfo->reg_lcd) {
311 		if (on) {
312 			ret = regulator_enable(sinfo->reg_lcd);
313 			if (ret)
314 				dev_err(&sinfo->pdev->dev,
315 					"lcd regulator enable failed:	%d\n", ret);
316 		} else {
317 			ret = regulator_disable(sinfo->reg_lcd);
318 			if (ret)
319 				dev_err(&sinfo->pdev->dev,
320 					"lcd regulator disable failed: %d\n", ret);
321 		}
322 	}
323 }
324 
325 static struct fb_fix_screeninfo atmel_lcdfb_fix __initdata = {
326 	.type		= FB_TYPE_PACKED_PIXELS,
327 	.visual		= FB_VISUAL_TRUECOLOR,
328 	.xpanstep	= 0,
329 	.ypanstep	= 1,
330 	.ywrapstep	= 0,
331 	.accel		= FB_ACCEL_NONE,
332 };
333 
334 static unsigned long compute_hozval(struct atmel_lcdfb_info *sinfo,
335 							unsigned long xres)
336 {
337 	unsigned long lcdcon2;
338 	unsigned long value;
339 
340 	if (!sinfo->config->have_hozval)
341 		return xres;
342 
343 	lcdcon2 = lcdc_readl(sinfo, ATMEL_LCDC_LCDCON2);
344 	value = xres;
345 	if ((lcdcon2 & ATMEL_LCDC_DISTYPE) != ATMEL_LCDC_DISTYPE_TFT) {
346 		/* STN display */
347 		if ((lcdcon2 & ATMEL_LCDC_DISTYPE) == ATMEL_LCDC_DISTYPE_STNCOLOR) {
348 			value *= 3;
349 		}
350 		if ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_4
351 		   || ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_8
352 		      && (lcdcon2 & ATMEL_LCDC_SCANMOD) == ATMEL_LCDC_SCANMOD_DUAL ))
353 			value = DIV_ROUND_UP(value, 4);
354 		else
355 			value = DIV_ROUND_UP(value, 8);
356 	}
357 
358 	return value;
359 }
360 
361 static void atmel_lcdfb_stop_nowait(struct atmel_lcdfb_info *sinfo)
362 {
363 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
364 
365 	/* Turn off the LCD controller and the DMA controller */
366 	lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
367 			pdata->guard_time << ATMEL_LCDC_GUARDT_OFFSET);
368 
369 	/* Wait for the LCDC core to become idle */
370 	while (lcdc_readl(sinfo, ATMEL_LCDC_PWRCON) & ATMEL_LCDC_BUSY)
371 		msleep(10);
372 
373 	lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0);
374 }
375 
376 static void atmel_lcdfb_stop(struct atmel_lcdfb_info *sinfo)
377 {
378 	atmel_lcdfb_stop_nowait(sinfo);
379 
380 	/* Wait for DMA engine to become idle... */
381 	while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
382 		msleep(10);
383 }
384 
385 static void atmel_lcdfb_start(struct atmel_lcdfb_info *sinfo)
386 {
387 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
388 
389 	lcdc_writel(sinfo, ATMEL_LCDC_DMACON, pdata->default_dmacon);
390 	lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
391 		(pdata->guard_time << ATMEL_LCDC_GUARDT_OFFSET)
392 		| ATMEL_LCDC_PWR);
393 }
394 
395 static void atmel_lcdfb_update_dma(struct fb_info *info,
396 			       struct fb_var_screeninfo *var)
397 {
398 	struct atmel_lcdfb_info *sinfo = info->par;
399 	struct fb_fix_screeninfo *fix = &info->fix;
400 	unsigned long dma_addr;
401 
402 	dma_addr = (fix->smem_start + var->yoffset * fix->line_length
403 		    + var->xoffset * info->var.bits_per_pixel / 8);
404 
405 	dma_addr &= ~3UL;
406 
407 	/* Set framebuffer DMA base address and pixel offset */
408 	lcdc_writel(sinfo, ATMEL_LCDC_DMABADDR1, dma_addr);
409 
410 	atmel_lcdfb_update_dma2d(sinfo, var, info);
411 }
412 
413 static inline void atmel_lcdfb_free_video_memory(struct atmel_lcdfb_info *sinfo)
414 {
415 	struct fb_info *info = sinfo->info;
416 
417 	dma_free_writecombine(info->device, info->fix.smem_len,
418 				info->screen_base, info->fix.smem_start);
419 }
420 
421 /**
422  *	atmel_lcdfb_alloc_video_memory - Allocate framebuffer memory
423  *	@sinfo: the frame buffer to allocate memory for
424  *
425  * 	This function is called only from the atmel_lcdfb_probe()
426  * 	so no locking by fb_info->mm_lock around smem_len setting is needed.
427  */
428 static int atmel_lcdfb_alloc_video_memory(struct atmel_lcdfb_info *sinfo)
429 {
430 	struct fb_info *info = sinfo->info;
431 	struct fb_var_screeninfo *var = &info->var;
432 	unsigned int smem_len;
433 
434 	smem_len = (var->xres_virtual * var->yres_virtual
435 		    * ((var->bits_per_pixel + 7) / 8));
436 	info->fix.smem_len = max(smem_len, sinfo->smem_len);
437 
438 	info->screen_base = dma_alloc_writecombine(info->device, info->fix.smem_len,
439 					(dma_addr_t *)&info->fix.smem_start, GFP_KERNEL);
440 
441 	if (!info->screen_base) {
442 		return -ENOMEM;
443 	}
444 
445 	memset(info->screen_base, 0, info->fix.smem_len);
446 
447 	return 0;
448 }
449 
450 static const struct fb_videomode *atmel_lcdfb_choose_mode(struct fb_var_screeninfo *var,
451 						     struct fb_info *info)
452 {
453 	struct fb_videomode varfbmode;
454 	const struct fb_videomode *fbmode = NULL;
455 
456 	fb_var_to_videomode(&varfbmode, var);
457 	fbmode = fb_find_nearest_mode(&varfbmode, &info->modelist);
458 	if (fbmode)
459 		fb_videomode_to_var(var, fbmode);
460 	return fbmode;
461 }
462 
463 
464 /**
465  *      atmel_lcdfb_check_var - Validates a var passed in.
466  *      @var: frame buffer variable screen structure
467  *      @info: frame buffer structure that represents a single frame buffer
468  *
469  *	Checks to see if the hardware supports the state requested by
470  *	var passed in. This function does not alter the hardware
471  *	state!!!  This means the data stored in struct fb_info and
472  *	struct atmel_lcdfb_info do not change. This includes the var
473  *	inside of struct fb_info.  Do NOT change these. This function
474  *	can be called on its own if we intent to only test a mode and
475  *	not actually set it. The stuff in modedb.c is a example of
476  *	this. If the var passed in is slightly off by what the
477  *	hardware can support then we alter the var PASSED in to what
478  *	we can do. If the hardware doesn't support mode change a
479  *	-EINVAL will be returned by the upper layers. You don't need
480  *	to implement this function then. If you hardware doesn't
481  *	support changing the resolution then this function is not
482  *	needed. In this case the driver would just provide a var that
483  *	represents the static state the screen is in.
484  *
485  *	Returns negative errno on error, or zero on success.
486  */
487 static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
488 			     struct fb_info *info)
489 {
490 	struct device *dev = info->device;
491 	struct atmel_lcdfb_info *sinfo = info->par;
492 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
493 	unsigned long clk_value_khz;
494 
495 	clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
496 
497 	dev_dbg(dev, "%s:\n", __func__);
498 
499 	if (!(var->pixclock && var->bits_per_pixel)) {
500 		/* choose a suitable mode if possible */
501 		if (!atmel_lcdfb_choose_mode(var, info)) {
502 			dev_err(dev, "needed value not specified\n");
503 			return -EINVAL;
504 		}
505 	}
506 
507 	dev_dbg(dev, "  resolution: %ux%u\n", var->xres, var->yres);
508 	dev_dbg(dev, "  pixclk:     %lu KHz\n", PICOS2KHZ(var->pixclock));
509 	dev_dbg(dev, "  bpp:        %u\n", var->bits_per_pixel);
510 	dev_dbg(dev, "  clk:        %lu KHz\n", clk_value_khz);
511 
512 	if (PICOS2KHZ(var->pixclock) > clk_value_khz) {
513 		dev_err(dev, "%lu KHz pixel clock is too fast\n", PICOS2KHZ(var->pixclock));
514 		return -EINVAL;
515 	}
516 
517 	/* Do not allow to have real resoulution larger than virtual */
518 	if (var->xres > var->xres_virtual)
519 		var->xres_virtual = var->xres;
520 
521 	if (var->yres > var->yres_virtual)
522 		var->yres_virtual = var->yres;
523 
524 	/* Force same alignment for each line */
525 	var->xres = (var->xres + 3) & ~3UL;
526 	var->xres_virtual = (var->xres_virtual + 3) & ~3UL;
527 
528 	var->red.msb_right = var->green.msb_right = var->blue.msb_right = 0;
529 	var->transp.msb_right = 0;
530 	var->transp.offset = var->transp.length = 0;
531 	var->xoffset = var->yoffset = 0;
532 
533 	if (info->fix.smem_len) {
534 		unsigned int smem_len = (var->xres_virtual * var->yres_virtual
535 					 * ((var->bits_per_pixel + 7) / 8));
536 		if (smem_len > info->fix.smem_len) {
537 			dev_err(dev, "Frame buffer is too small (%u) for screen size (need at least %u)\n",
538 				info->fix.smem_len, smem_len);
539 			return -EINVAL;
540 		}
541 	}
542 
543 	/* Saturate vertical and horizontal timings at maximum values */
544 	var->vsync_len = min_t(u32, var->vsync_len,
545 			(ATMEL_LCDC_VPW >> ATMEL_LCDC_VPW_OFFSET) + 1);
546 	var->upper_margin = min_t(u32, var->upper_margin,
547 			ATMEL_LCDC_VBP >> ATMEL_LCDC_VBP_OFFSET);
548 	var->lower_margin = min_t(u32, var->lower_margin,
549 			ATMEL_LCDC_VFP);
550 	var->right_margin = min_t(u32, var->right_margin,
551 			(ATMEL_LCDC_HFP >> ATMEL_LCDC_HFP_OFFSET) + 1);
552 	var->hsync_len = min_t(u32, var->hsync_len,
553 			(ATMEL_LCDC_HPW >> ATMEL_LCDC_HPW_OFFSET) + 1);
554 	var->left_margin = min_t(u32, var->left_margin,
555 			ATMEL_LCDC_HBP + 1);
556 
557 	/* Some parameters can't be zero */
558 	var->vsync_len = max_t(u32, var->vsync_len, 1);
559 	var->right_margin = max_t(u32, var->right_margin, 1);
560 	var->hsync_len = max_t(u32, var->hsync_len, 1);
561 	var->left_margin = max_t(u32, var->left_margin, 1);
562 
563 	switch (var->bits_per_pixel) {
564 	case 1:
565 	case 2:
566 	case 4:
567 	case 8:
568 		var->red.offset = var->green.offset = var->blue.offset = 0;
569 		var->red.length = var->green.length = var->blue.length
570 			= var->bits_per_pixel;
571 		break;
572 	case 16:
573 		/* Older SOCs use IBGR:555 rather than BGR:565. */
574 		if (sinfo->config->have_intensity_bit)
575 			var->green.length = 5;
576 		else
577 			var->green.length = 6;
578 
579 		if (pdata->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
580 			/* RGB:5X5 mode */
581 			var->red.offset = var->green.length + 5;
582 			var->blue.offset = 0;
583 		} else {
584 			/* BGR:5X5 mode */
585 			var->red.offset = 0;
586 			var->blue.offset = var->green.length + 5;
587 		}
588 		var->green.offset = 5;
589 		var->red.length = var->blue.length = 5;
590 		break;
591 	case 32:
592 		var->transp.offset = 24;
593 		var->transp.length = 8;
594 		/* fall through */
595 	case 24:
596 		if (pdata->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
597 			/* RGB:888 mode */
598 			var->red.offset = 16;
599 			var->blue.offset = 0;
600 		} else {
601 			/* BGR:888 mode */
602 			var->red.offset = 0;
603 			var->blue.offset = 16;
604 		}
605 		var->green.offset = 8;
606 		var->red.length = var->green.length = var->blue.length = 8;
607 		break;
608 	default:
609 		dev_err(dev, "color depth %d not supported\n",
610 					var->bits_per_pixel);
611 		return -EINVAL;
612 	}
613 
614 	return 0;
615 }
616 
617 /*
618  * LCD reset sequence
619  */
620 static void atmel_lcdfb_reset(struct atmel_lcdfb_info *sinfo)
621 {
622 	might_sleep();
623 
624 	atmel_lcdfb_stop(sinfo);
625 	atmel_lcdfb_start(sinfo);
626 }
627 
628 /**
629  *      atmel_lcdfb_set_par - Alters the hardware state.
630  *      @info: frame buffer structure that represents a single frame buffer
631  *
632  *	Using the fb_var_screeninfo in fb_info we set the resolution
633  *	of the this particular framebuffer. This function alters the
634  *	par AND the fb_fix_screeninfo stored in fb_info. It doesn't
635  *	not alter var in fb_info since we are using that data. This
636  *	means we depend on the data in var inside fb_info to be
637  *	supported by the hardware.  atmel_lcdfb_check_var is always called
638  *	before atmel_lcdfb_set_par to ensure this.  Again if you can't
639  *	change the resolution you don't need this function.
640  *
641  */
642 static int atmel_lcdfb_set_par(struct fb_info *info)
643 {
644 	struct atmel_lcdfb_info *sinfo = info->par;
645 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
646 	unsigned long hozval_linesz;
647 	unsigned long value;
648 	unsigned long clk_value_khz;
649 	unsigned long bits_per_line;
650 	unsigned long pix_factor = 2;
651 
652 	might_sleep();
653 
654 	dev_dbg(info->device, "%s:\n", __func__);
655 	dev_dbg(info->device, "  * resolution: %ux%u (%ux%u virtual)\n",
656 		 info->var.xres, info->var.yres,
657 		 info->var.xres_virtual, info->var.yres_virtual);
658 
659 	atmel_lcdfb_stop_nowait(sinfo);
660 
661 	if (info->var.bits_per_pixel == 1)
662 		info->fix.visual = FB_VISUAL_MONO01;
663 	else if (info->var.bits_per_pixel <= 8)
664 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
665 	else
666 		info->fix.visual = FB_VISUAL_TRUECOLOR;
667 
668 	bits_per_line = info->var.xres_virtual * info->var.bits_per_pixel;
669 	info->fix.line_length = DIV_ROUND_UP(bits_per_line, 8);
670 
671 	/* Re-initialize the DMA engine... */
672 	dev_dbg(info->device, "  * update DMA engine\n");
673 	atmel_lcdfb_update_dma(info, &info->var);
674 
675 	/* ...set frame size and burst length = 8 words (?) */
676 	value = (info->var.yres * info->var.xres * info->var.bits_per_pixel) / 32;
677 	value |= ((ATMEL_LCDC_DMA_BURST_LEN - 1) << ATMEL_LCDC_BLENGTH_OFFSET);
678 	lcdc_writel(sinfo, ATMEL_LCDC_DMAFRMCFG, value);
679 
680 	/* Now, the LCDC core... */
681 
682 	/* Set pixel clock */
683 	if (sinfo->config->have_alt_pixclock)
684 		pix_factor = 1;
685 
686 	clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
687 
688 	value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));
689 
690 	if (value < pix_factor) {
691 		dev_notice(info->device, "Bypassing pixel clock divider\n");
692 		lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
693 	} else {
694 		value = (value / pix_factor) - 1;
695 		dev_dbg(info->device, "  * programming CLKVAL = 0x%08lx\n",
696 				value);
697 		lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1,
698 				value << ATMEL_LCDC_CLKVAL_OFFSET);
699 		info->var.pixclock =
700 			KHZ2PICOS(clk_value_khz / (pix_factor * (value + 1)));
701 		dev_dbg(info->device, "  updated pixclk:     %lu KHz\n",
702 					PICOS2KHZ(info->var.pixclock));
703 	}
704 
705 
706 	/* Initialize control register 2 */
707 	value = pdata->default_lcdcon2;
708 
709 	if (!(info->var.sync & FB_SYNC_HOR_HIGH_ACT))
710 		value |= ATMEL_LCDC_INVLINE_INVERTED;
711 	if (!(info->var.sync & FB_SYNC_VERT_HIGH_ACT))
712 		value |= ATMEL_LCDC_INVFRAME_INVERTED;
713 
714 	switch (info->var.bits_per_pixel) {
715 		case 1:	value |= ATMEL_LCDC_PIXELSIZE_1; break;
716 		case 2: value |= ATMEL_LCDC_PIXELSIZE_2; break;
717 		case 4: value |= ATMEL_LCDC_PIXELSIZE_4; break;
718 		case 8: value |= ATMEL_LCDC_PIXELSIZE_8; break;
719 		case 15: /* fall through */
720 		case 16: value |= ATMEL_LCDC_PIXELSIZE_16; break;
721 		case 24: value |= ATMEL_LCDC_PIXELSIZE_24; break;
722 		case 32: value |= ATMEL_LCDC_PIXELSIZE_32; break;
723 		default: BUG(); break;
724 	}
725 	dev_dbg(info->device, "  * LCDCON2 = %08lx\n", value);
726 	lcdc_writel(sinfo, ATMEL_LCDC_LCDCON2, value);
727 
728 	/* Vertical timing */
729 	value = (info->var.vsync_len - 1) << ATMEL_LCDC_VPW_OFFSET;
730 	value |= info->var.upper_margin << ATMEL_LCDC_VBP_OFFSET;
731 	value |= info->var.lower_margin;
732 	dev_dbg(info->device, "  * LCDTIM1 = %08lx\n", value);
733 	lcdc_writel(sinfo, ATMEL_LCDC_TIM1, value);
734 
735 	/* Horizontal timing */
736 	value = (info->var.right_margin - 1) << ATMEL_LCDC_HFP_OFFSET;
737 	value |= (info->var.hsync_len - 1) << ATMEL_LCDC_HPW_OFFSET;
738 	value |= (info->var.left_margin - 1);
739 	dev_dbg(info->device, "  * LCDTIM2 = %08lx\n", value);
740 	lcdc_writel(sinfo, ATMEL_LCDC_TIM2, value);
741 
742 	/* Horizontal value (aka line size) */
743 	hozval_linesz = compute_hozval(sinfo, info->var.xres);
744 
745 	/* Display size */
746 	value = (hozval_linesz - 1) << ATMEL_LCDC_HOZVAL_OFFSET;
747 	value |= info->var.yres - 1;
748 	dev_dbg(info->device, "  * LCDFRMCFG = %08lx\n", value);
749 	lcdc_writel(sinfo, ATMEL_LCDC_LCDFRMCFG, value);
750 
751 	/* FIFO Threshold: Use formula from data sheet */
752 	value = ATMEL_LCDC_FIFO_SIZE - (2 * ATMEL_LCDC_DMA_BURST_LEN + 3);
753 	lcdc_writel(sinfo, ATMEL_LCDC_FIFO, value);
754 
755 	/* Toggle LCD_MODE every frame */
756 	lcdc_writel(sinfo, ATMEL_LCDC_MVAL, 0);
757 
758 	/* Disable all interrupts */
759 	lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);
760 	/* Enable FIFO & DMA errors */
761 	lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI | ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);
762 
763 	/* ...wait for DMA engine to become idle... */
764 	while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
765 		msleep(10);
766 
767 	atmel_lcdfb_start(sinfo);
768 
769 	dev_dbg(info->device, "  * DONE\n");
770 
771 	return 0;
772 }
773 
774 static inline unsigned int chan_to_field(unsigned int chan, const struct fb_bitfield *bf)
775 {
776 	chan &= 0xffff;
777 	chan >>= 16 - bf->length;
778 	return chan << bf->offset;
779 }
780 
781 /**
782  *  	atmel_lcdfb_setcolreg - Optional function. Sets a color register.
783  *      @regno: Which register in the CLUT we are programming
784  *      @red: The red value which can be up to 16 bits wide
785  *	@green: The green value which can be up to 16 bits wide
786  *	@blue:  The blue value which can be up to 16 bits wide.
787  *	@transp: If supported the alpha value which can be up to 16 bits wide.
788  *      @info: frame buffer info structure
789  *
790  *  	Set a single color register. The values supplied have a 16 bit
791  *  	magnitude which needs to be scaled in this function for the hardware.
792  *	Things to take into consideration are how many color registers, if
793  *	any, are supported with the current color visual. With truecolor mode
794  *	no color palettes are supported. Here a pseudo palette is created
795  *	which we store the value in pseudo_palette in struct fb_info. For
796  *	pseudocolor mode we have a limited color palette. To deal with this
797  *	we can program what color is displayed for a particular pixel value.
798  *	DirectColor is similar in that we can program each color field. If
799  *	we have a static colormap we don't need to implement this function.
800  *
801  *	Returns negative errno on error, or zero on success. In an
802  *	ideal world, this would have been the case, but as it turns
803  *	out, the other drivers return 1 on failure, so that's what
804  *	we're going to do.
805  */
806 static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
807 			     unsigned int green, unsigned int blue,
808 			     unsigned int transp, struct fb_info *info)
809 {
810 	struct atmel_lcdfb_info *sinfo = info->par;
811 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
812 	unsigned int val;
813 	u32 *pal;
814 	int ret = 1;
815 
816 	if (info->var.grayscale)
817 		red = green = blue = (19595 * red + 38470 * green
818 				      + 7471 * blue) >> 16;
819 
820 	switch (info->fix.visual) {
821 	case FB_VISUAL_TRUECOLOR:
822 		if (regno < 16) {
823 			pal = info->pseudo_palette;
824 
825 			val  = chan_to_field(red, &info->var.red);
826 			val |= chan_to_field(green, &info->var.green);
827 			val |= chan_to_field(blue, &info->var.blue);
828 
829 			pal[regno] = val;
830 			ret = 0;
831 		}
832 		break;
833 
834 	case FB_VISUAL_PSEUDOCOLOR:
835 		if (regno < 256) {
836 			if (sinfo->config->have_intensity_bit) {
837 				/* old style I+BGR:555 */
838 				val  = ((red   >> 11) & 0x001f);
839 				val |= ((green >>  6) & 0x03e0);
840 				val |= ((blue  >>  1) & 0x7c00);
841 
842 				/*
843 				 * TODO: intensity bit. Maybe something like
844 				 *   ~(red[10] ^ green[10] ^ blue[10]) & 1
845 				 */
846 			} else {
847 				/* new style BGR:565 / RGB:565 */
848 				if (pdata->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
849 					val  = ((blue >> 11) & 0x001f);
850 					val |= ((red  >>  0) & 0xf800);
851 				} else {
852 					val  = ((red  >> 11) & 0x001f);
853 					val |= ((blue >>  0) & 0xf800);
854 				}
855 
856 				val |= ((green >>  5) & 0x07e0);
857 			}
858 
859 			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
860 			ret = 0;
861 		}
862 		break;
863 
864 	case FB_VISUAL_MONO01:
865 		if (regno < 2) {
866 			val = (regno == 0) ? 0x00 : 0x1F;
867 			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
868 			ret = 0;
869 		}
870 		break;
871 
872 	}
873 
874 	return ret;
875 }
876 
877 static int atmel_lcdfb_pan_display(struct fb_var_screeninfo *var,
878 			       struct fb_info *info)
879 {
880 	dev_dbg(info->device, "%s\n", __func__);
881 
882 	atmel_lcdfb_update_dma(info, var);
883 
884 	return 0;
885 }
886 
887 static int atmel_lcdfb_blank(int blank_mode, struct fb_info *info)
888 {
889 	struct atmel_lcdfb_info *sinfo = info->par;
890 
891 	switch (blank_mode) {
892 	case FB_BLANK_UNBLANK:
893 	case FB_BLANK_NORMAL:
894 		atmel_lcdfb_start(sinfo);
895 		break;
896 	case FB_BLANK_VSYNC_SUSPEND:
897 	case FB_BLANK_HSYNC_SUSPEND:
898 		break;
899 	case FB_BLANK_POWERDOWN:
900 		atmel_lcdfb_stop(sinfo);
901 		break;
902 	default:
903 		return -EINVAL;
904 	}
905 
906 	/* let fbcon do a soft blank for us */
907 	return ((blank_mode == FB_BLANK_NORMAL) ? 1 : 0);
908 }
909 
910 static struct fb_ops atmel_lcdfb_ops = {
911 	.owner		= THIS_MODULE,
912 	.fb_check_var	= atmel_lcdfb_check_var,
913 	.fb_set_par	= atmel_lcdfb_set_par,
914 	.fb_setcolreg	= atmel_lcdfb_setcolreg,
915 	.fb_blank	= atmel_lcdfb_blank,
916 	.fb_pan_display	= atmel_lcdfb_pan_display,
917 	.fb_fillrect	= cfb_fillrect,
918 	.fb_copyarea	= cfb_copyarea,
919 	.fb_imageblit	= cfb_imageblit,
920 };
921 
922 static irqreturn_t atmel_lcdfb_interrupt(int irq, void *dev_id)
923 {
924 	struct fb_info *info = dev_id;
925 	struct atmel_lcdfb_info *sinfo = info->par;
926 	u32 status;
927 
928 	status = lcdc_readl(sinfo, ATMEL_LCDC_ISR);
929 	if (status & ATMEL_LCDC_UFLWI) {
930 		dev_warn(info->device, "FIFO underflow %#x\n", status);
931 		/* reset DMA and FIFO to avoid screen shifting */
932 		schedule_work(&sinfo->task);
933 	}
934 	lcdc_writel(sinfo, ATMEL_LCDC_ICR, status);
935 	return IRQ_HANDLED;
936 }
937 
938 /*
939  * LCD controller task (to reset the LCD)
940  */
941 static void atmel_lcdfb_task(struct work_struct *work)
942 {
943 	struct atmel_lcdfb_info *sinfo =
944 		container_of(work, struct atmel_lcdfb_info, task);
945 
946 	atmel_lcdfb_reset(sinfo);
947 }
948 
949 static int __init atmel_lcdfb_init_fbinfo(struct atmel_lcdfb_info *sinfo)
950 {
951 	struct fb_info *info = sinfo->info;
952 	int ret = 0;
953 
954 	info->var.activate |= FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;
955 
956 	dev_info(info->device,
957 	       "%luKiB frame buffer at %08lx (mapped at %p)\n",
958 	       (unsigned long)info->fix.smem_len / 1024,
959 	       (unsigned long)info->fix.smem_start,
960 	       info->screen_base);
961 
962 	/* Allocate colormap */
963 	ret = fb_alloc_cmap(&info->cmap, 256, 0);
964 	if (ret < 0)
965 		dev_err(info->device, "Alloc color map failed\n");
966 
967 	return ret;
968 }
969 
970 static void atmel_lcdfb_start_clock(struct atmel_lcdfb_info *sinfo)
971 {
972 	clk_prepare_enable(sinfo->bus_clk);
973 	clk_prepare_enable(sinfo->lcdc_clk);
974 }
975 
976 static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
977 {
978 	clk_disable_unprepare(sinfo->bus_clk);
979 	clk_disable_unprepare(sinfo->lcdc_clk);
980 }
981 
982 #ifdef CONFIG_OF
983 static const struct of_device_id atmel_lcdfb_dt_ids[] = {
984 	{ .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
985 	{ .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
986 	{ .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
987 	{ .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
988 	{ .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
989 	{ .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
990 	{ .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
991 	{ /* sentinel */ }
992 };
993 
994 MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
995 
996 static const char *atmel_lcdfb_wiring_modes[] = {
997 	[ATMEL_LCDC_WIRING_BGR]	= "BRG",
998 	[ATMEL_LCDC_WIRING_RGB]	= "RGB",
999 };
1000 
1001 static int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
1002 {
1003 	const char *mode;
1004 	int err, i;
1005 
1006 	err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
1007 	if (err < 0)
1008 		return ATMEL_LCDC_WIRING_BGR;
1009 
1010 	for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
1011 		if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
1012 			return i;
1013 
1014 	return -ENODEV;
1015 }
1016 
1017 static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
1018 {
1019 	struct atmel_lcdfb_power_ctrl_gpio *og;
1020 
1021 	list_for_each_entry(og, &pdata->pwr_gpios, list)
1022 		gpio_set_value(og->gpio, on);
1023 }
1024 
1025 static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
1026 {
1027 	struct fb_info *info = sinfo->info;
1028 	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
1029 	struct fb_var_screeninfo *var = &info->var;
1030 	struct device *dev = &sinfo->pdev->dev;
1031 	struct device_node *np =dev->of_node;
1032 	struct device_node *display_np;
1033 	struct device_node *timings_np;
1034 	struct display_timings *timings;
1035 	enum of_gpio_flags flags;
1036 	struct atmel_lcdfb_power_ctrl_gpio *og;
1037 	bool is_gpio_power = false;
1038 	int ret = -ENOENT;
1039 	int i, gpio;
1040 
1041 	sinfo->config = (struct atmel_lcdfb_config*)
1042 		of_match_device(atmel_lcdfb_dt_ids, dev)->data;
1043 
1044 	display_np = of_parse_phandle(np, "display", 0);
1045 	if (!display_np) {
1046 		dev_err(dev, "failed to find display phandle\n");
1047 		return -ENOENT;
1048 	}
1049 
1050 	ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
1051 	if (ret < 0) {
1052 		dev_err(dev, "failed to get property bits-per-pixel\n");
1053 		goto put_display_node;
1054 	}
1055 
1056 	ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
1057 	if (ret < 0) {
1058 		dev_err(dev, "failed to get property atmel,guard-time\n");
1059 		goto put_display_node;
1060 	}
1061 
1062 	ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
1063 	if (ret < 0) {
1064 		dev_err(dev, "failed to get property atmel,lcdcon2\n");
1065 		goto put_display_node;
1066 	}
1067 
1068 	ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
1069 	if (ret < 0) {
1070 		dev_err(dev, "failed to get property bits-per-pixel\n");
1071 		goto put_display_node;
1072 	}
1073 
1074 	INIT_LIST_HEAD(&pdata->pwr_gpios);
1075 	ret = -ENOMEM;
1076 	for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
1077 		gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
1078 					       i, &flags);
1079 		if (gpio < 0)
1080 			continue;
1081 
1082 		og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
1083 		if (!og)
1084 			goto put_display_node;
1085 
1086 		og->gpio = gpio;
1087 		og->active_low = flags & OF_GPIO_ACTIVE_LOW;
1088 		is_gpio_power = true;
1089 		ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
1090 		if (ret) {
1091 			dev_err(dev, "request gpio %d failed\n", gpio);
1092 			goto put_display_node;
1093 		}
1094 
1095 		ret = gpio_direction_output(gpio, og->active_low);
1096 		if (ret) {
1097 			dev_err(dev, "set direction output gpio %d failed\n", gpio);
1098 			goto put_display_node;
1099 		}
1100 		list_add(&og->list, &pdata->pwr_gpios);
1101 	}
1102 
1103 	if (is_gpio_power)
1104 		pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
1105 
1106 	ret = atmel_lcdfb_get_of_wiring_modes(display_np);
1107 	if (ret < 0) {
1108 		dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
1109 		goto put_display_node;
1110 	}
1111 	pdata->lcd_wiring_mode = ret;
1112 
1113 	pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
1114 	pdata->lcdcon_pol_negative = of_property_read_bool(display_np, "atmel,lcdcon-backlight-inverted");
1115 
1116 	timings = of_get_display_timings(display_np);
1117 	if (!timings) {
1118 		dev_err(dev, "failed to get display timings\n");
1119 		ret = -EINVAL;
1120 		goto put_display_node;
1121 	}
1122 
1123 	timings_np = of_find_node_by_name(display_np, "display-timings");
1124 	if (!timings_np) {
1125 		dev_err(dev, "failed to find display-timings node\n");
1126 		ret = -ENODEV;
1127 		goto put_display_node;
1128 	}
1129 
1130 	for (i = 0; i < of_get_child_count(timings_np); i++) {
1131 		struct videomode vm;
1132 		struct fb_videomode fb_vm;
1133 
1134 		ret = videomode_from_timings(timings, &vm, i);
1135 		if (ret < 0)
1136 			goto put_timings_node;
1137 		ret = fb_videomode_from_videomode(&vm, &fb_vm);
1138 		if (ret < 0)
1139 			goto put_timings_node;
1140 
1141 		fb_add_videomode(&fb_vm, &info->modelist);
1142 	}
1143 
1144 	return 0;
1145 
1146 put_timings_node:
1147 	of_node_put(timings_np);
1148 put_display_node:
1149 	of_node_put(display_np);
1150 	return ret;
1151 }
1152 #else
1153 static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
1154 {
1155 	return 0;
1156 }
1157 #endif
1158 
1159 static int __init atmel_lcdfb_probe(struct platform_device *pdev)
1160 {
1161 	struct device *dev = &pdev->dev;
1162 	struct fb_info *info;
1163 	struct atmel_lcdfb_info *sinfo;
1164 	struct atmel_lcdfb_pdata *pdata = NULL;
1165 	struct resource *regs = NULL;
1166 	struct resource *map = NULL;
1167 	struct fb_modelist *modelist;
1168 	int ret;
1169 
1170 	dev_dbg(dev, "%s BEGIN\n", __func__);
1171 
1172 	ret = -ENOMEM;
1173 	info = framebuffer_alloc(sizeof(struct atmel_lcdfb_info), dev);
1174 	if (!info) {
1175 		dev_err(dev, "cannot allocate memory\n");
1176 		goto out;
1177 	}
1178 
1179 	sinfo = info->par;
1180 	sinfo->pdev = pdev;
1181 	sinfo->info = info;
1182 
1183 	INIT_LIST_HEAD(&info->modelist);
1184 
1185 	if (pdev->dev.of_node) {
1186 		ret = atmel_lcdfb_of_init(sinfo);
1187 		if (ret)
1188 			goto free_info;
1189 	} else if (dev_get_platdata(dev)) {
1190 		struct fb_monspecs *monspecs;
1191 		int i;
1192 
1193 		pdata = dev_get_platdata(dev);
1194 		monspecs = pdata->default_monspecs;
1195 		sinfo->pdata = *pdata;
1196 
1197 		for (i = 0; i < monspecs->modedb_len; i++)
1198 			fb_add_videomode(&monspecs->modedb[i], &info->modelist);
1199 
1200 		sinfo->config = atmel_lcdfb_get_config(pdev);
1201 
1202 		info->var.bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
1203 		memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
1204 	} else {
1205 		dev_err(dev, "cannot get default configuration\n");
1206 		goto free_info;
1207 	}
1208 
1209 	if (!sinfo->config)
1210 		goto free_info;
1211 
1212 	sinfo->reg_lcd = devm_regulator_get(&pdev->dev, "lcd");
1213 	if (IS_ERR(sinfo->reg_lcd))
1214 		sinfo->reg_lcd = NULL;
1215 
1216 	info->flags = ATMEL_LCDFB_FBINFO_DEFAULT;
1217 	info->pseudo_palette = sinfo->pseudo_palette;
1218 	info->fbops = &atmel_lcdfb_ops;
1219 
1220 	info->fix = atmel_lcdfb_fix;
1221 	strcpy(info->fix.id, sinfo->pdev->name);
1222 
1223 	/* Enable LCDC Clocks */
1224 	sinfo->bus_clk = clk_get(dev, "hclk");
1225 	if (IS_ERR(sinfo->bus_clk)) {
1226 		ret = PTR_ERR(sinfo->bus_clk);
1227 		goto free_info;
1228 	}
1229 	sinfo->lcdc_clk = clk_get(dev, "lcdc_clk");
1230 	if (IS_ERR(sinfo->lcdc_clk)) {
1231 		ret = PTR_ERR(sinfo->lcdc_clk);
1232 		goto put_bus_clk;
1233 	}
1234 	atmel_lcdfb_start_clock(sinfo);
1235 
1236 	modelist = list_first_entry(&info->modelist,
1237 			struct fb_modelist, list);
1238 	fb_videomode_to_var(&info->var, &modelist->mode);
1239 
1240 	atmel_lcdfb_check_var(&info->var, info);
1241 
1242 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1243 	if (!regs) {
1244 		dev_err(dev, "resources unusable\n");
1245 		ret = -ENXIO;
1246 		goto stop_clk;
1247 	}
1248 
1249 	sinfo->irq_base = platform_get_irq(pdev, 0);
1250 	if (sinfo->irq_base < 0) {
1251 		dev_err(dev, "unable to get irq\n");
1252 		ret = sinfo->irq_base;
1253 		goto stop_clk;
1254 	}
1255 
1256 	/* Initialize video memory */
1257 	map = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1258 	if (map) {
1259 		/* use a pre-allocated memory buffer */
1260 		info->fix.smem_start = map->start;
1261 		info->fix.smem_len = resource_size(map);
1262 		if (!request_mem_region(info->fix.smem_start,
1263 					info->fix.smem_len, pdev->name)) {
1264 			ret = -EBUSY;
1265 			goto stop_clk;
1266 		}
1267 
1268 		info->screen_base = ioremap_wc(info->fix.smem_start,
1269 					       info->fix.smem_len);
1270 		if (!info->screen_base) {
1271 			ret = -ENOMEM;
1272 			goto release_intmem;
1273 		}
1274 
1275 		/*
1276 		 * Don't clear the framebuffer -- someone may have set
1277 		 * up a splash image.
1278 		 */
1279 	} else {
1280 		/* allocate memory buffer */
1281 		ret = atmel_lcdfb_alloc_video_memory(sinfo);
1282 		if (ret < 0) {
1283 			dev_err(dev, "cannot allocate framebuffer: %d\n", ret);
1284 			goto stop_clk;
1285 		}
1286 	}
1287 
1288 	/* LCDC registers */
1289 	info->fix.mmio_start = regs->start;
1290 	info->fix.mmio_len = resource_size(regs);
1291 
1292 	if (!request_mem_region(info->fix.mmio_start,
1293 				info->fix.mmio_len, pdev->name)) {
1294 		ret = -EBUSY;
1295 		goto free_fb;
1296 	}
1297 
1298 	sinfo->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
1299 	if (!sinfo->mmio) {
1300 		dev_err(dev, "cannot map LCDC registers\n");
1301 		ret = -ENOMEM;
1302 		goto release_mem;
1303 	}
1304 
1305 	/* Initialize PWM for contrast or backlight ("off") */
1306 	init_contrast(sinfo);
1307 
1308 	/* interrupt */
1309 	ret = request_irq(sinfo->irq_base, atmel_lcdfb_interrupt, 0, pdev->name, info);
1310 	if (ret) {
1311 		dev_err(dev, "request_irq failed: %d\n", ret);
1312 		goto unmap_mmio;
1313 	}
1314 
1315 	/* Some operations on the LCDC might sleep and
1316 	 * require a preemptible task context */
1317 	INIT_WORK(&sinfo->task, atmel_lcdfb_task);
1318 
1319 	ret = atmel_lcdfb_init_fbinfo(sinfo);
1320 	if (ret < 0) {
1321 		dev_err(dev, "init fbinfo failed: %d\n", ret);
1322 		goto unregister_irqs;
1323 	}
1324 
1325 	ret = atmel_lcdfb_set_par(info);
1326 	if (ret < 0) {
1327 		dev_err(dev, "set par failed: %d\n", ret);
1328 		goto unregister_irqs;
1329 	}
1330 
1331 	dev_set_drvdata(dev, info);
1332 
1333 	/*
1334 	 * Tell the world that we're ready to go
1335 	 */
1336 	ret = register_framebuffer(info);
1337 	if (ret < 0) {
1338 		dev_err(dev, "failed to register framebuffer device: %d\n", ret);
1339 		goto reset_drvdata;
1340 	}
1341 
1342 	/* Power up the LCDC screen */
1343 	atmel_lcdfb_power_control(sinfo, 1);
1344 
1345 	dev_info(dev, "fb%d: Atmel LCDC at 0x%08lx (mapped at %p), irq %d\n",
1346 		       info->node, info->fix.mmio_start, sinfo->mmio, sinfo->irq_base);
1347 
1348 	return 0;
1349 
1350 reset_drvdata:
1351 	dev_set_drvdata(dev, NULL);
1352 	fb_dealloc_cmap(&info->cmap);
1353 unregister_irqs:
1354 	cancel_work_sync(&sinfo->task);
1355 	free_irq(sinfo->irq_base, info);
1356 unmap_mmio:
1357 	exit_backlight(sinfo);
1358 	iounmap(sinfo->mmio);
1359 release_mem:
1360  	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
1361 free_fb:
1362 	if (map)
1363 		iounmap(info->screen_base);
1364 	else
1365 		atmel_lcdfb_free_video_memory(sinfo);
1366 
1367 release_intmem:
1368 	if (map)
1369 		release_mem_region(info->fix.smem_start, info->fix.smem_len);
1370 stop_clk:
1371 	atmel_lcdfb_stop_clock(sinfo);
1372 	clk_put(sinfo->lcdc_clk);
1373 put_bus_clk:
1374 	clk_put(sinfo->bus_clk);
1375 free_info:
1376 	framebuffer_release(info);
1377 out:
1378 	dev_dbg(dev, "%s FAILED\n", __func__);
1379 	return ret;
1380 }
1381 
1382 static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
1383 {
1384 	struct device *dev = &pdev->dev;
1385 	struct fb_info *info = dev_get_drvdata(dev);
1386 	struct atmel_lcdfb_info *sinfo;
1387 	struct atmel_lcdfb_pdata *pdata;
1388 
1389 	if (!info || !info->par)
1390 		return 0;
1391 	sinfo = info->par;
1392 	pdata = &sinfo->pdata;
1393 
1394 	cancel_work_sync(&sinfo->task);
1395 	exit_backlight(sinfo);
1396 	atmel_lcdfb_power_control(sinfo, 0);
1397 	unregister_framebuffer(info);
1398 	atmel_lcdfb_stop_clock(sinfo);
1399 	clk_put(sinfo->lcdc_clk);
1400 	clk_put(sinfo->bus_clk);
1401 	fb_dealloc_cmap(&info->cmap);
1402 	free_irq(sinfo->irq_base, info);
1403 	iounmap(sinfo->mmio);
1404  	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
1405 	if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) {
1406 		iounmap(info->screen_base);
1407 		release_mem_region(info->fix.smem_start, info->fix.smem_len);
1408 	} else {
1409 		atmel_lcdfb_free_video_memory(sinfo);
1410 	}
1411 
1412 	framebuffer_release(info);
1413 
1414 	return 0;
1415 }
1416 
1417 #ifdef CONFIG_PM
1418 
1419 static int atmel_lcdfb_suspend(struct platform_device *pdev, pm_message_t mesg)
1420 {
1421 	struct fb_info *info = platform_get_drvdata(pdev);
1422 	struct atmel_lcdfb_info *sinfo = info->par;
1423 
1424 	/*
1425 	 * We don't want to handle interrupts while the clock is
1426 	 * stopped. It may take forever.
1427 	 */
1428 	lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);
1429 
1430 	sinfo->saved_lcdcon = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_CTR);
1431 	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, 0);
1432 	atmel_lcdfb_power_control(sinfo, 0);
1433 	atmel_lcdfb_stop(sinfo);
1434 	atmel_lcdfb_stop_clock(sinfo);
1435 
1436 	return 0;
1437 }
1438 
1439 static int atmel_lcdfb_resume(struct platform_device *pdev)
1440 {
1441 	struct fb_info *info = platform_get_drvdata(pdev);
1442 	struct atmel_lcdfb_info *sinfo = info->par;
1443 
1444 	atmel_lcdfb_start_clock(sinfo);
1445 	atmel_lcdfb_start(sinfo);
1446 	atmel_lcdfb_power_control(sinfo, 1);
1447 	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, sinfo->saved_lcdcon);
1448 
1449 	/* Enable FIFO & DMA errors */
1450 	lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI
1451 			| ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);
1452 
1453 	return 0;
1454 }
1455 
1456 #else
1457 #define atmel_lcdfb_suspend	NULL
1458 #define atmel_lcdfb_resume	NULL
1459 #endif
1460 
1461 static struct platform_driver atmel_lcdfb_driver = {
1462 	.remove		= __exit_p(atmel_lcdfb_remove),
1463 	.suspend	= atmel_lcdfb_suspend,
1464 	.resume		= atmel_lcdfb_resume,
1465 	.id_table	= atmel_lcdfb_devtypes,
1466 	.driver		= {
1467 		.name	= "atmel_lcdfb",
1468 		.of_match_table	= of_match_ptr(atmel_lcdfb_dt_ids),
1469 	},
1470 };
1471 
1472 module_platform_driver_probe(atmel_lcdfb_driver, atmel_lcdfb_probe);
1473 
1474 MODULE_DESCRIPTION("AT91/AT32 LCD Controller framebuffer driver");
1475 MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>");
1476 MODULE_LICENSE("GPL");
1477