xref: /openbmc/linux/drivers/gpu/drm/kmb/kmb_drv.c (revision 79e790ff)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright © 2018-2020 Intel Corporation
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/module.h>
8 #include <linux/of_graph.h>
9 #include <linux/of_platform.h>
10 #include <linux/of_reserved_mem.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/platform_device.h>
13 #include <linux/pm_runtime.h>
14 #include <linux/regmap.h>
15 
16 #include <drm/drm_atomic_helper.h>
17 #include <drm/drm_drv.h>
18 #include <drm/drm_gem_cma_helper.h>
19 #include <drm/drm_gem_framebuffer_helper.h>
20 #include <drm/drm_irq.h>
21 #include <drm/drm_probe_helper.h>
22 #include <drm/drm_vblank.h>
23 
24 #include "kmb_drv.h"
25 #include "kmb_dsi.h"
26 #include "kmb_regs.h"
27 
28 static int kmb_display_clk_enable(struct kmb_drm_private *kmb)
29 {
30 	int ret = 0;
31 
32 	ret = clk_prepare_enable(kmb->kmb_clk.clk_lcd);
33 	if (ret) {
34 		drm_err(&kmb->drm, "Failed to enable LCD clock: %d\n", ret);
35 		return ret;
36 	}
37 	DRM_INFO("SUCCESS : enabled LCD clocks\n");
38 	return 0;
39 }
40 
41 static int kmb_initialize_clocks(struct kmb_drm_private *kmb, struct device *dev)
42 {
43 	int ret = 0;
44 	struct regmap *msscam;
45 
46 	kmb->kmb_clk.clk_lcd = devm_clk_get(dev, "clk_lcd");
47 	if (IS_ERR(kmb->kmb_clk.clk_lcd)) {
48 		drm_err(&kmb->drm, "clk_get() failed clk_lcd\n");
49 		return PTR_ERR(kmb->kmb_clk.clk_lcd);
50 	}
51 
52 	kmb->kmb_clk.clk_pll0 = devm_clk_get(dev, "clk_pll0");
53 	if (IS_ERR(kmb->kmb_clk.clk_pll0)) {
54 		drm_err(&kmb->drm, "clk_get() failed clk_pll0 ");
55 		return PTR_ERR(kmb->kmb_clk.clk_pll0);
56 	}
57 	kmb->sys_clk_mhz = clk_get_rate(kmb->kmb_clk.clk_pll0) / 1000000;
58 	drm_info(&kmb->drm, "system clk = %d Mhz", kmb->sys_clk_mhz);
59 
60 	ret =  kmb_dsi_clk_init(kmb->kmb_dsi);
61 
62 	/* Set LCD clock to 200 Mhz */
63 	clk_set_rate(kmb->kmb_clk.clk_lcd, KMB_LCD_DEFAULT_CLK);
64 	if (clk_get_rate(kmb->kmb_clk.clk_lcd) != KMB_LCD_DEFAULT_CLK) {
65 		drm_err(&kmb->drm, "failed to set to clk_lcd to %d\n",
66 			KMB_LCD_DEFAULT_CLK);
67 		return -1;
68 	}
69 	drm_dbg(&kmb->drm, "clk_lcd = %ld\n", clk_get_rate(kmb->kmb_clk.clk_lcd));
70 
71 	ret = kmb_display_clk_enable(kmb);
72 	if (ret)
73 		return ret;
74 
75 	msscam = syscon_regmap_lookup_by_compatible("intel,keembay-msscam");
76 	if (IS_ERR(msscam)) {
77 		drm_err(&kmb->drm, "failed to get msscam syscon");
78 		return -1;
79 	}
80 
81 	/* Enable MSS_CAM_CLK_CTRL for MIPI TX and LCD */
82 	regmap_update_bits(msscam, MSS_CAM_CLK_CTRL, 0x1fff, 0x1fff);
83 	regmap_update_bits(msscam, MSS_CAM_RSTN_CTRL, 0xffffffff, 0xffffffff);
84 	return 0;
85 }
86 
87 static void kmb_display_clk_disable(struct kmb_drm_private *kmb)
88 {
89 	clk_disable_unprepare(kmb->kmb_clk.clk_lcd);
90 }
91 
92 static void __iomem *kmb_map_mmio(struct drm_device *drm,
93 				  struct platform_device *pdev,
94 				  char *name)
95 {
96 	struct resource *res;
97 	void __iomem *mem;
98 
99 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
100 	if (!res) {
101 		drm_err(drm, "failed to get resource for %s", name);
102 		return ERR_PTR(-ENOMEM);
103 	}
104 	mem = devm_ioremap_resource(drm->dev, res);
105 	if (IS_ERR(mem))
106 		drm_err(drm, "failed to ioremap %s registers", name);
107 	return mem;
108 }
109 
110 static int kmb_hw_init(struct drm_device *drm, unsigned long flags)
111 {
112 	struct kmb_drm_private *kmb = to_kmb(drm);
113 	struct platform_device *pdev = to_platform_device(drm->dev);
114 	int irq_lcd;
115 	int ret = 0;
116 
117 	/* Map LCD MMIO registers */
118 	kmb->lcd_mmio = kmb_map_mmio(drm, pdev, "lcd");
119 	if (IS_ERR(kmb->lcd_mmio)) {
120 		drm_err(&kmb->drm, "failed to map LCD registers\n");
121 		return -ENOMEM;
122 	}
123 
124 	/* Map MIPI MMIO registers */
125 	ret = kmb_dsi_map_mmio(kmb->kmb_dsi);
126 	if (ret)
127 		return ret;
128 
129 	/* Enable display clocks */
130 	kmb_initialize_clocks(kmb, &pdev->dev);
131 
132 	/* Register irqs here - section 17.3 in databook
133 	 * lists LCD at 79 and 82 for MIPI under MSS CPU -
134 	 * firmware has redirected 79 to A53 IRQ 33
135 	 */
136 
137 	/* Allocate LCD interrupt resources */
138 	irq_lcd = platform_get_irq(pdev, 0);
139 	if (irq_lcd < 0) {
140 		drm_err(&kmb->drm, "irq_lcd not found");
141 		goto setup_fail;
142 	}
143 
144 	/* Get the optional framebuffer memory resource */
145 	ret = of_reserved_mem_device_init(drm->dev);
146 	if (ret && ret != -ENODEV)
147 		return ret;
148 
149 	spin_lock_init(&kmb->irq_lock);
150 
151 	kmb->irq_lcd = irq_lcd;
152 
153 	return 0;
154 
155  setup_fail:
156 	of_reserved_mem_device_release(drm->dev);
157 
158 	return ret;
159 }
160 
161 static const struct drm_mode_config_funcs kmb_mode_config_funcs = {
162 	.fb_create = drm_gem_fb_create,
163 	.atomic_check = drm_atomic_helper_check,
164 	.atomic_commit = drm_atomic_helper_commit,
165 };
166 
167 static int kmb_setup_mode_config(struct drm_device *drm)
168 {
169 	int ret;
170 	struct kmb_drm_private *kmb = to_kmb(drm);
171 
172 	ret = drmm_mode_config_init(drm);
173 	if (ret)
174 		return ret;
175 	drm->mode_config.min_width = KMB_MIN_WIDTH;
176 	drm->mode_config.min_height = KMB_MIN_HEIGHT;
177 	drm->mode_config.max_width = KMB_MAX_WIDTH;
178 	drm->mode_config.max_height = KMB_MAX_HEIGHT;
179 	drm->mode_config.funcs = &kmb_mode_config_funcs;
180 
181 	ret = kmb_setup_crtc(drm);
182 	if (ret < 0) {
183 		drm_err(drm, "failed to create crtc\n");
184 		return ret;
185 	}
186 	ret = kmb_dsi_encoder_init(drm, kmb->kmb_dsi);
187 	/* Set the CRTC's port so that the encoder component can find it */
188 	kmb->crtc.port = of_graph_get_port_by_id(drm->dev->of_node, 0);
189 	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
190 	if (ret < 0) {
191 		drm_err(drm, "failed to initialize vblank\n");
192 		pm_runtime_disable(drm->dev);
193 		return ret;
194 	}
195 
196 	drm_mode_config_reset(drm);
197 	return 0;
198 }
199 
200 static irqreturn_t handle_lcd_irq(struct drm_device *dev)
201 {
202 	unsigned long status, val, val1;
203 	int plane_id, dma0_state, dma1_state;
204 	struct kmb_drm_private *kmb = to_kmb(dev);
205 
206 	status = kmb_read_lcd(kmb, LCD_INT_STATUS);
207 
208 	spin_lock(&kmb->irq_lock);
209 	if (status & LCD_INT_EOF) {
210 		kmb_write_lcd(kmb, LCD_INT_CLEAR, LCD_INT_EOF);
211 
212 		/* When disabling/enabling LCD layers, the change takes effect
213 		 * immediately and does not wait for EOF (end of frame).
214 		 * When kmb_plane_atomic_disable is called, mark the plane as
215 		 * disabled but actually disable the plane when EOF irq is
216 		 * being handled.
217 		 */
218 		for (plane_id = LAYER_0;
219 				plane_id < KMB_MAX_PLANES; plane_id++) {
220 			if (kmb->plane_status[plane_id].disable) {
221 				kmb_clr_bitmask_lcd(kmb,
222 						    LCD_LAYERn_DMA_CFG
223 						    (plane_id),
224 						    LCD_DMA_LAYER_ENABLE);
225 
226 				kmb_clr_bitmask_lcd(kmb, LCD_CONTROL,
227 						    kmb->plane_status[plane_id].ctrl);
228 
229 				kmb->plane_status[plane_id].disable = false;
230 			}
231 		}
232 		if (kmb->kmb_under_flow) {
233 			/* DMA Recovery after underflow */
234 			dma0_state = (kmb->layer_no == 0) ?
235 			    LCD_VIDEO0_DMA0_STATE : LCD_VIDEO1_DMA0_STATE;
236 			dma1_state = (kmb->layer_no == 0) ?
237 			    LCD_VIDEO0_DMA1_STATE : LCD_VIDEO1_DMA1_STATE;
238 
239 			do {
240 				kmb_write_lcd(kmb, LCD_FIFO_FLUSH, 1);
241 				val = kmb_read_lcd(kmb, dma0_state)
242 				    & LCD_DMA_STATE_ACTIVE;
243 				val1 = kmb_read_lcd(kmb, dma1_state)
244 				    & LCD_DMA_STATE_ACTIVE;
245 			} while ((val || val1));
246 			/* disable dma */
247 			kmb_clr_bitmask_lcd(kmb,
248 					    LCD_LAYERn_DMA_CFG(kmb->layer_no),
249 					    LCD_DMA_LAYER_ENABLE);
250 			kmb_write_lcd(kmb, LCD_FIFO_FLUSH, 1);
251 			kmb->kmb_flush_done = 1;
252 			kmb->kmb_under_flow = 0;
253 		}
254 	}
255 
256 	if (status & LCD_INT_LINE_CMP) {
257 		/* clear line compare interrupt */
258 		kmb_write_lcd(kmb, LCD_INT_CLEAR, LCD_INT_LINE_CMP);
259 	}
260 
261 	if (status & LCD_INT_VERT_COMP) {
262 		/* Read VSTATUS */
263 		val = kmb_read_lcd(kmb, LCD_VSTATUS);
264 		val = (val & LCD_VSTATUS_VERTICAL_STATUS_MASK);
265 		switch (val) {
266 		case LCD_VSTATUS_COMPARE_VSYNC:
267 			/* Clear vertical compare interrupt */
268 			kmb_write_lcd(kmb, LCD_INT_CLEAR, LCD_INT_VERT_COMP);
269 			if (kmb->kmb_flush_done) {
270 				kmb_set_bitmask_lcd(kmb,
271 						    LCD_LAYERn_DMA_CFG
272 						    (kmb->layer_no),
273 						    LCD_DMA_LAYER_ENABLE);
274 				kmb->kmb_flush_done = 0;
275 			}
276 			drm_crtc_handle_vblank(&kmb->crtc);
277 			break;
278 		case LCD_VSTATUS_COMPARE_BACKPORCH:
279 		case LCD_VSTATUS_COMPARE_ACTIVE:
280 		case LCD_VSTATUS_COMPARE_FRONT_PORCH:
281 			kmb_write_lcd(kmb, LCD_INT_CLEAR, LCD_INT_VERT_COMP);
282 			break;
283 		}
284 	}
285 	if (status & LCD_INT_DMA_ERR) {
286 		val =
287 		    (status & LCD_INT_DMA_ERR &
288 		     kmb_read_lcd(kmb, LCD_INT_ENABLE));
289 		/* LAYER0 - VL0 */
290 		if (val & (LAYER0_DMA_FIFO_UNDERFLOW |
291 			   LAYER0_DMA_CB_FIFO_UNDERFLOW |
292 			   LAYER0_DMA_CR_FIFO_UNDERFLOW)) {
293 			kmb->kmb_under_flow++;
294 			drm_info(&kmb->drm,
295 				 "!LAYER0:VL0 DMA UNDERFLOW val = 0x%lx,under_flow=%d",
296 			     val, kmb->kmb_under_flow);
297 			/* disable underflow interrupt */
298 			kmb_clr_bitmask_lcd(kmb, LCD_INT_ENABLE,
299 					    LAYER0_DMA_FIFO_UNDERFLOW |
300 					    LAYER0_DMA_CB_FIFO_UNDERFLOW |
301 					    LAYER0_DMA_CR_FIFO_UNDERFLOW);
302 			kmb_set_bitmask_lcd(kmb, LCD_INT_CLEAR,
303 					    LAYER0_DMA_CB_FIFO_UNDERFLOW |
304 					    LAYER0_DMA_FIFO_UNDERFLOW |
305 					    LAYER0_DMA_CR_FIFO_UNDERFLOW);
306 			/* disable auto restart mode */
307 			kmb_clr_bitmask_lcd(kmb, LCD_LAYERn_DMA_CFG(0),
308 					    LCD_DMA_LAYER_CONT_PING_PONG_UPDATE);
309 
310 			kmb->layer_no = 0;
311 		}
312 
313 		if (val & LAYER0_DMA_FIFO_OVERFLOW)
314 			drm_dbg(&kmb->drm,
315 				"LAYER0:VL0 DMA OVERFLOW val = 0x%lx", val);
316 		if (val & LAYER0_DMA_CB_FIFO_OVERFLOW)
317 			drm_dbg(&kmb->drm,
318 				"LAYER0:VL0 DMA CB OVERFLOW val = 0x%lx", val);
319 		if (val & LAYER0_DMA_CR_FIFO_OVERFLOW)
320 			drm_dbg(&kmb->drm,
321 				"LAYER0:VL0 DMA CR OVERFLOW val = 0x%lx", val);
322 
323 		/* LAYER1 - VL1 */
324 		if (val & (LAYER1_DMA_FIFO_UNDERFLOW |
325 			   LAYER1_DMA_CB_FIFO_UNDERFLOW |
326 			   LAYER1_DMA_CR_FIFO_UNDERFLOW)) {
327 			kmb->kmb_under_flow++;
328 			drm_info(&kmb->drm,
329 				 "!LAYER1:VL1 DMA UNDERFLOW val = 0x%lx, under_flow=%d",
330 			     val, kmb->kmb_under_flow);
331 			/* disable underflow interrupt */
332 			kmb_clr_bitmask_lcd(kmb, LCD_INT_ENABLE,
333 					    LAYER1_DMA_FIFO_UNDERFLOW |
334 					    LAYER1_DMA_CB_FIFO_UNDERFLOW |
335 					    LAYER1_DMA_CR_FIFO_UNDERFLOW);
336 			kmb_set_bitmask_lcd(kmb, LCD_INT_CLEAR,
337 					    LAYER1_DMA_CB_FIFO_UNDERFLOW |
338 					    LAYER1_DMA_FIFO_UNDERFLOW |
339 					    LAYER1_DMA_CR_FIFO_UNDERFLOW);
340 			/* disable auto restart mode */
341 			kmb_clr_bitmask_lcd(kmb, LCD_LAYERn_DMA_CFG(1),
342 					    LCD_DMA_LAYER_CONT_PING_PONG_UPDATE);
343 			kmb->layer_no = 1;
344 		}
345 
346 		/* LAYER1 - VL1 */
347 		if (val & LAYER1_DMA_FIFO_OVERFLOW)
348 			drm_dbg(&kmb->drm,
349 				"LAYER1:VL1 DMA OVERFLOW val = 0x%lx", val);
350 		if (val & LAYER1_DMA_CB_FIFO_OVERFLOW)
351 			drm_dbg(&kmb->drm,
352 				"LAYER1:VL1 DMA CB OVERFLOW val = 0x%lx", val);
353 		if (val & LAYER1_DMA_CR_FIFO_OVERFLOW)
354 			drm_dbg(&kmb->drm,
355 				"LAYER1:VL1 DMA CR OVERFLOW val = 0x%lx", val);
356 
357 		/* LAYER2 - GL0 */
358 		if (val & LAYER2_DMA_FIFO_UNDERFLOW)
359 			drm_dbg(&kmb->drm,
360 				"LAYER2:GL0 DMA UNDERFLOW val = 0x%lx", val);
361 		if (val & LAYER2_DMA_FIFO_OVERFLOW)
362 			drm_dbg(&kmb->drm,
363 				"LAYER2:GL0 DMA OVERFLOW val = 0x%lx", val);
364 
365 		/* LAYER3 - GL1 */
366 		if (val & LAYER3_DMA_FIFO_UNDERFLOW)
367 			drm_dbg(&kmb->drm,
368 				"LAYER3:GL1 DMA UNDERFLOW val = 0x%lx", val);
369 		if (val & LAYER3_DMA_FIFO_UNDERFLOW)
370 			drm_dbg(&kmb->drm,
371 				"LAYER3:GL1 DMA OVERFLOW val = 0x%lx", val);
372 	}
373 
374 	spin_unlock(&kmb->irq_lock);
375 
376 	if (status & LCD_INT_LAYER) {
377 		/* Clear layer interrupts */
378 		kmb_write_lcd(kmb, LCD_INT_CLEAR, LCD_INT_LAYER);
379 	}
380 
381 	/* Clear all interrupts */
382 	kmb_set_bitmask_lcd(kmb, LCD_INT_CLEAR, 1);
383 	return IRQ_HANDLED;
384 }
385 
386 /* IRQ handler */
387 static irqreturn_t kmb_isr(int irq, void *arg)
388 {
389 	struct drm_device *dev = (struct drm_device *)arg;
390 
391 	handle_lcd_irq(dev);
392 	return IRQ_HANDLED;
393 }
394 
395 static void kmb_irq_reset(struct drm_device *drm)
396 {
397 	kmb_write_lcd(to_kmb(drm), LCD_INT_CLEAR, 0xFFFF);
398 	kmb_write_lcd(to_kmb(drm), LCD_INT_ENABLE, 0);
399 }
400 
401 DEFINE_DRM_GEM_CMA_FOPS(fops);
402 
403 static const struct drm_driver kmb_driver = {
404 	.driver_features = DRIVER_GEM |
405 	    DRIVER_MODESET | DRIVER_ATOMIC,
406 	.irq_handler = kmb_isr,
407 	.irq_preinstall = kmb_irq_reset,
408 	.irq_uninstall = kmb_irq_reset,
409 	/* GEM Operations */
410 	.fops = &fops,
411 	DRM_GEM_CMA_DRIVER_OPS_VMAP,
412 	.name = "kmb-drm",
413 	.desc = "KEEMBAY DISPLAY DRIVER ",
414 	.date = "20201008",
415 	.major = 1,
416 	.minor = 0,
417 };
418 
419 static int kmb_remove(struct platform_device *pdev)
420 {
421 	struct device *dev = &pdev->dev;
422 	struct drm_device *drm = dev_get_drvdata(dev);
423 	struct kmb_drm_private *kmb = to_kmb(drm);
424 
425 	drm_dev_unregister(drm);
426 	drm_kms_helper_poll_fini(drm);
427 	of_node_put(kmb->crtc.port);
428 	kmb->crtc.port = NULL;
429 	pm_runtime_get_sync(drm->dev);
430 	drm_irq_uninstall(drm);
431 	pm_runtime_put_sync(drm->dev);
432 	pm_runtime_disable(drm->dev);
433 
434 	of_reserved_mem_device_release(drm->dev);
435 
436 	/* Release clks */
437 	kmb_display_clk_disable(kmb);
438 
439 	dev_set_drvdata(dev, NULL);
440 
441 	/* Unregister DSI host */
442 	kmb_dsi_host_unregister(kmb->kmb_dsi);
443 	drm_atomic_helper_shutdown(drm);
444 	return 0;
445 }
446 
447 static int kmb_probe(struct platform_device *pdev)
448 {
449 	struct device *dev = get_device(&pdev->dev);
450 	struct kmb_drm_private *kmb;
451 	int ret = 0;
452 	struct device_node *dsi_in;
453 	struct device_node *dsi_node;
454 	struct platform_device *dsi_pdev;
455 
456 	/* The bridge (ADV 7535) will return -EPROBE_DEFER until it
457 	 * has a mipi_dsi_host to register its device to. So, we
458 	 * first register the DSI host during probe time, and then return
459 	 * -EPROBE_DEFER until the bridge is loaded. Probe will be called again
460 	 *  and then the rest of the driver initialization can proceed
461 	 *  afterwards and the bridge can be successfully attached.
462 	 */
463 	dsi_in = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
464 	if (!dsi_in) {
465 		DRM_ERROR("Failed to get dsi_in node info from DT");
466 		return -EINVAL;
467 	}
468 	dsi_node = of_graph_get_remote_port_parent(dsi_in);
469 	if (!dsi_node) {
470 		of_node_put(dsi_in);
471 		DRM_ERROR("Failed to get dsi node from DT\n");
472 		return -EINVAL;
473 	}
474 
475 	dsi_pdev = of_find_device_by_node(dsi_node);
476 	if (!dsi_pdev) {
477 		of_node_put(dsi_in);
478 		of_node_put(dsi_node);
479 		DRM_ERROR("Failed to get dsi platform device\n");
480 		return -EINVAL;
481 	}
482 
483 	of_node_put(dsi_in);
484 	of_node_put(dsi_node);
485 	ret = kmb_dsi_host_bridge_init(get_device(&dsi_pdev->dev));
486 
487 	if (ret == -EPROBE_DEFER) {
488 		return -EPROBE_DEFER;
489 	} else if (ret) {
490 		DRM_ERROR("probe failed to initialize DSI host bridge\n");
491 		return ret;
492 	}
493 
494 	/* Create DRM device */
495 	kmb = devm_drm_dev_alloc(dev, &kmb_driver,
496 				 struct kmb_drm_private, drm);
497 	if (IS_ERR(kmb))
498 		return PTR_ERR(kmb);
499 
500 	dev_set_drvdata(dev, &kmb->drm);
501 
502 	/* Initialize MIPI DSI */
503 	kmb->kmb_dsi = kmb_dsi_init(dsi_pdev);
504 	if (IS_ERR(kmb->kmb_dsi)) {
505 		drm_err(&kmb->drm, "failed to initialize DSI\n");
506 		ret = PTR_ERR(kmb->kmb_dsi);
507 		goto err_free1;
508 	}
509 
510 	kmb->kmb_dsi->dev = &dsi_pdev->dev;
511 	kmb->kmb_dsi->pdev = dsi_pdev;
512 	ret = kmb_hw_init(&kmb->drm, 0);
513 	if (ret)
514 		goto err_free1;
515 
516 	ret = kmb_setup_mode_config(&kmb->drm);
517 	if (ret)
518 		goto err_free;
519 
520 	ret = drm_irq_install(&kmb->drm, kmb->irq_lcd);
521 	if (ret < 0) {
522 		drm_err(&kmb->drm, "failed to install IRQ handler\n");
523 		goto err_irq;
524 	}
525 
526 	drm_kms_helper_poll_init(&kmb->drm);
527 
528 	/* Register graphics device with the kernel */
529 	ret = drm_dev_register(&kmb->drm, 0);
530 	if (ret)
531 		goto err_register;
532 
533 	return 0;
534 
535  err_register:
536 	drm_kms_helper_poll_fini(&kmb->drm);
537  err_irq:
538 	pm_runtime_disable(kmb->drm.dev);
539  err_free:
540 	drm_crtc_cleanup(&kmb->crtc);
541 	drm_mode_config_cleanup(&kmb->drm);
542  err_free1:
543 	dev_set_drvdata(dev, NULL);
544 	kmb_dsi_host_unregister(kmb->kmb_dsi);
545 
546 	return ret;
547 }
548 
549 static const struct of_device_id kmb_of_match[] = {
550 	{.compatible = "intel,keembay-display"},
551 	{},
552 };
553 
554 MODULE_DEVICE_TABLE(of, kmb_of_match);
555 
556 static int __maybe_unused kmb_pm_suspend(struct device *dev)
557 {
558 	struct drm_device *drm = dev_get_drvdata(dev);
559 	struct kmb_drm_private *kmb = to_kmb(drm);
560 
561 	drm_kms_helper_poll_disable(drm);
562 
563 	kmb->state = drm_atomic_helper_suspend(drm);
564 	if (IS_ERR(kmb->state)) {
565 		drm_kms_helper_poll_enable(drm);
566 		return PTR_ERR(kmb->state);
567 	}
568 
569 	return 0;
570 }
571 
572 static int __maybe_unused kmb_pm_resume(struct device *dev)
573 {
574 	struct drm_device *drm = dev_get_drvdata(dev);
575 	struct kmb_drm_private *kmb = drm ? to_kmb(drm) : NULL;
576 
577 	if (!kmb)
578 		return 0;
579 
580 	drm_atomic_helper_resume(drm, kmb->state);
581 	drm_kms_helper_poll_enable(drm);
582 
583 	return 0;
584 }
585 
586 static SIMPLE_DEV_PM_OPS(kmb_pm_ops, kmb_pm_suspend, kmb_pm_resume);
587 
588 static struct platform_driver kmb_platform_driver = {
589 	.probe = kmb_probe,
590 	.remove = kmb_remove,
591 	.driver = {
592 		.name = "kmb-drm",
593 		.pm = &kmb_pm_ops,
594 		.of_match_table = kmb_of_match,
595 	},
596 };
597 
598 module_platform_driver(kmb_platform_driver);
599 
600 MODULE_AUTHOR("Intel Corporation");
601 MODULE_DESCRIPTION("Keembay Display driver");
602 MODULE_LICENSE("GPL v2");
603