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