1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * i.MX8 NWL MIPI DSI host driver
4  *
5  * Copyright (C) 2017 NXP
6  * Copyright (C) 2020 Purism SPC
7  */
8 
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/irq.h>
12 #include <linux/math64.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/mux/consumer.h>
16 #include <linux/of.h>
17 #include <linux/of_platform.h>
18 #include <linux/phy/phy.h>
19 #include <linux/regmap.h>
20 #include <linux/reset.h>
21 #include <linux/sys_soc.h>
22 #include <linux/time64.h>
23 
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_mipi_dsi.h>
26 #include <drm/drm_of.h>
27 #include <drm/drm_panel.h>
28 #include <drm/drm_print.h>
29 
30 #include <video/mipi_display.h>
31 
32 #include "nwl-dsi.h"
33 
34 #define DRV_NAME "nwl-dsi"
35 
36 /* i.MX8 NWL quirks */
37 /* i.MX8MQ errata E11418 */
38 #define E11418_HS_MODE_QUIRK	BIT(0)
39 
40 #define NWL_DSI_MIPI_FIFO_TIMEOUT msecs_to_jiffies(500)
41 
42 enum transfer_direction {
43 	DSI_PACKET_SEND,
44 	DSI_PACKET_RECEIVE,
45 };
46 
47 #define NWL_DSI_ENDPOINT_LCDIF 0
48 #define NWL_DSI_ENDPOINT_DCSS 1
49 
50 struct nwl_dsi_plat_clk_config {
51 	const char *id;
52 	struct clk *clk;
53 	bool present;
54 };
55 
56 struct nwl_dsi_transfer {
57 	const struct mipi_dsi_msg *msg;
58 	struct mipi_dsi_packet packet;
59 	struct completion completed;
60 
61 	int status; /* status of transmission */
62 	enum transfer_direction direction;
63 	bool need_bta;
64 	u8 cmd;
65 	u16 rx_word_count;
66 	size_t tx_len; /* in bytes */
67 	size_t rx_len; /* in bytes */
68 };
69 
70 struct nwl_dsi {
71 	struct drm_bridge bridge;
72 	struct mipi_dsi_host dsi_host;
73 	struct drm_bridge *panel_bridge;
74 	struct device *dev;
75 	struct phy *phy;
76 	union phy_configure_opts phy_cfg;
77 	unsigned int quirks;
78 
79 	struct regmap *regmap;
80 	int irq;
81 	/*
82 	 * The DSI host controller needs this reset sequence according to NWL:
83 	 * 1. Deassert pclk reset to get access to DSI regs
84 	 * 2. Configure DSI Host and DPHY and enable DPHY
85 	 * 3. Deassert ESC and BYTE resets to allow host TX operations)
86 	 * 4. Send DSI cmds to configure peripheral (handled by panel drv)
87 	 * 5. Deassert DPI reset so DPI receives pixels and starts sending
88 	 *    DSI data
89 	 *
90 	 * TODO: Since panel_bridges do their DSI setup in enable we
91 	 * currently have 4. and 5. swapped.
92 	 */
93 	struct reset_control *rst_byte;
94 	struct reset_control *rst_esc;
95 	struct reset_control *rst_dpi;
96 	struct reset_control *rst_pclk;
97 	struct mux_control *mux;
98 
99 	/* DSI clocks */
100 	struct clk *phy_ref_clk;
101 	struct clk *rx_esc_clk;
102 	struct clk *tx_esc_clk;
103 	struct clk *core_clk;
104 	/*
105 	 * hardware bug: the i.MX8MQ needs this clock on during reset
106 	 * even when not using LCDIF.
107 	 */
108 	struct clk *lcdif_clk;
109 
110 	/* dsi lanes */
111 	u32 lanes;
112 	enum mipi_dsi_pixel_format format;
113 	struct drm_display_mode mode;
114 	unsigned long dsi_mode_flags;
115 	int error;
116 
117 	struct nwl_dsi_transfer *xfer;
118 };
119 
120 static const struct regmap_config nwl_dsi_regmap_config = {
121 	.reg_bits = 16,
122 	.val_bits = 32,
123 	.reg_stride = 4,
124 	.max_register = NWL_DSI_IRQ_MASK2,
125 	.name = DRV_NAME,
126 };
127 
bridge_to_dsi(struct drm_bridge * bridge)128 static inline struct nwl_dsi *bridge_to_dsi(struct drm_bridge *bridge)
129 {
130 	return container_of(bridge, struct nwl_dsi, bridge);
131 }
132 
nwl_dsi_clear_error(struct nwl_dsi * dsi)133 static int nwl_dsi_clear_error(struct nwl_dsi *dsi)
134 {
135 	int ret = dsi->error;
136 
137 	dsi->error = 0;
138 	return ret;
139 }
140 
nwl_dsi_write(struct nwl_dsi * dsi,unsigned int reg,u32 val)141 static void nwl_dsi_write(struct nwl_dsi *dsi, unsigned int reg, u32 val)
142 {
143 	int ret;
144 
145 	if (dsi->error)
146 		return;
147 
148 	ret = regmap_write(dsi->regmap, reg, val);
149 	if (ret < 0) {
150 		DRM_DEV_ERROR(dsi->dev,
151 			      "Failed to write NWL DSI reg 0x%x: %d\n", reg,
152 			      ret);
153 		dsi->error = ret;
154 	}
155 }
156 
nwl_dsi_read(struct nwl_dsi * dsi,u32 reg)157 static u32 nwl_dsi_read(struct nwl_dsi *dsi, u32 reg)
158 {
159 	unsigned int val;
160 	int ret;
161 
162 	if (dsi->error)
163 		return 0;
164 
165 	ret = regmap_read(dsi->regmap, reg, &val);
166 	if (ret < 0) {
167 		DRM_DEV_ERROR(dsi->dev, "Failed to read NWL DSI reg 0x%x: %d\n",
168 			      reg, ret);
169 		dsi->error = ret;
170 	}
171 	return val;
172 }
173 
nwl_dsi_get_dpi_pixel_format(enum mipi_dsi_pixel_format format)174 static int nwl_dsi_get_dpi_pixel_format(enum mipi_dsi_pixel_format format)
175 {
176 	switch (format) {
177 	case MIPI_DSI_FMT_RGB565:
178 		return NWL_DSI_PIXEL_FORMAT_16;
179 	case MIPI_DSI_FMT_RGB666:
180 		return NWL_DSI_PIXEL_FORMAT_18L;
181 	case MIPI_DSI_FMT_RGB666_PACKED:
182 		return NWL_DSI_PIXEL_FORMAT_18;
183 	case MIPI_DSI_FMT_RGB888:
184 		return NWL_DSI_PIXEL_FORMAT_24;
185 	default:
186 		return -EINVAL;
187 	}
188 }
189 
190 /*
191  * ps2bc - Picoseconds to byte clock cycles
192  */
ps2bc(struct nwl_dsi * dsi,unsigned long long ps)193 static u32 ps2bc(struct nwl_dsi *dsi, unsigned long long ps)
194 {
195 	u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
196 
197 	return DIV64_U64_ROUND_UP(ps * dsi->mode.clock * bpp,
198 				  dsi->lanes * 8 * NSEC_PER_SEC);
199 }
200 
201 /*
202  * ui2bc - UI time periods to byte clock cycles
203  */
ui2bc(struct nwl_dsi * dsi,unsigned long long ui)204 static u32 ui2bc(struct nwl_dsi *dsi, unsigned long long ui)
205 {
206 	u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
207 
208 	return DIV64_U64_ROUND_UP(ui * dsi->lanes,
209 				  dsi->mode.clock * 1000 * bpp);
210 }
211 
212 /*
213  * us2bc - micro seconds to lp clock cycles
214  */
us2lp(u32 lp_clk_rate,unsigned long us)215 static u32 us2lp(u32 lp_clk_rate, unsigned long us)
216 {
217 	return DIV_ROUND_UP(us * lp_clk_rate, USEC_PER_SEC);
218 }
219 
nwl_dsi_config_host(struct nwl_dsi * dsi)220 static int nwl_dsi_config_host(struct nwl_dsi *dsi)
221 {
222 	u32 cycles;
223 	struct phy_configure_opts_mipi_dphy *cfg = &dsi->phy_cfg.mipi_dphy;
224 
225 	if (dsi->lanes < 1 || dsi->lanes > 4)
226 		return -EINVAL;
227 
228 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "DSI Lanes %d\n", dsi->lanes);
229 	nwl_dsi_write(dsi, NWL_DSI_CFG_NUM_LANES, dsi->lanes - 1);
230 
231 	if (dsi->dsi_mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
232 		nwl_dsi_write(dsi, NWL_DSI_CFG_NONCONTINUOUS_CLK, 0x01);
233 		nwl_dsi_write(dsi, NWL_DSI_CFG_AUTOINSERT_EOTP, 0x01);
234 	} else {
235 		nwl_dsi_write(dsi, NWL_DSI_CFG_NONCONTINUOUS_CLK, 0x00);
236 		nwl_dsi_write(dsi, NWL_DSI_CFG_AUTOINSERT_EOTP, 0x00);
237 	}
238 
239 	/* values in byte clock cycles */
240 	cycles = ui2bc(dsi, cfg->clk_pre);
241 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_pre: 0x%x\n", cycles);
242 	nwl_dsi_write(dsi, NWL_DSI_CFG_T_PRE, cycles);
243 	cycles = ps2bc(dsi, cfg->lpx + cfg->clk_prepare + cfg->clk_zero);
244 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap (pre): 0x%x\n", cycles);
245 	cycles += ui2bc(dsi, cfg->clk_pre);
246 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_post: 0x%x\n", cycles);
247 	nwl_dsi_write(dsi, NWL_DSI_CFG_T_POST, cycles);
248 	cycles = ps2bc(dsi, cfg->hs_exit);
249 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap: 0x%x\n", cycles);
250 	nwl_dsi_write(dsi, NWL_DSI_CFG_TX_GAP, cycles);
251 
252 	nwl_dsi_write(dsi, NWL_DSI_CFG_EXTRA_CMDS_AFTER_EOTP, 0x01);
253 	nwl_dsi_write(dsi, NWL_DSI_CFG_HTX_TO_COUNT, 0x00);
254 	nwl_dsi_write(dsi, NWL_DSI_CFG_LRX_H_TO_COUNT, 0x00);
255 	nwl_dsi_write(dsi, NWL_DSI_CFG_BTA_H_TO_COUNT, 0x00);
256 	/* In LP clock cycles */
257 	cycles = us2lp(cfg->lp_clk_rate, cfg->wakeup);
258 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_twakeup: 0x%x\n", cycles);
259 	nwl_dsi_write(dsi, NWL_DSI_CFG_TWAKEUP, cycles);
260 
261 	return nwl_dsi_clear_error(dsi);
262 }
263 
nwl_dsi_config_dpi(struct nwl_dsi * dsi)264 static int nwl_dsi_config_dpi(struct nwl_dsi *dsi)
265 {
266 	u32 mode;
267 	int color_format;
268 	bool burst_mode;
269 	int hfront_porch, hback_porch, vfront_porch, vback_porch;
270 	int hsync_len, vsync_len;
271 
272 	hfront_porch = dsi->mode.hsync_start - dsi->mode.hdisplay;
273 	hsync_len = dsi->mode.hsync_end - dsi->mode.hsync_start;
274 	hback_porch = dsi->mode.htotal - dsi->mode.hsync_end;
275 
276 	vfront_porch = dsi->mode.vsync_start - dsi->mode.vdisplay;
277 	vsync_len = dsi->mode.vsync_end - dsi->mode.vsync_start;
278 	vback_porch = dsi->mode.vtotal - dsi->mode.vsync_end;
279 
280 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hfront_porch = %d\n", hfront_porch);
281 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hback_porch = %d\n", hback_porch);
282 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hsync_len = %d\n", hsync_len);
283 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hdisplay = %d\n", dsi->mode.hdisplay);
284 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vfront_porch = %d\n", vfront_porch);
285 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vback_porch = %d\n", vback_porch);
286 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vsync_len = %d\n", vsync_len);
287 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vactive = %d\n", dsi->mode.vdisplay);
288 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "clock = %d kHz\n", dsi->mode.clock);
289 
290 	color_format = nwl_dsi_get_dpi_pixel_format(dsi->format);
291 	if (color_format < 0) {
292 		DRM_DEV_ERROR(dsi->dev, "Invalid color format 0x%x\n",
293 			      dsi->format);
294 		return color_format;
295 	}
296 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "pixel fmt = %d\n", dsi->format);
297 
298 	nwl_dsi_write(dsi, NWL_DSI_INTERFACE_COLOR_CODING, NWL_DSI_DPI_24_BIT);
299 	nwl_dsi_write(dsi, NWL_DSI_PIXEL_FORMAT, color_format);
300 	/*
301 	 * Adjusting input polarity based on the video mode results in
302 	 * a black screen so always pick active low:
303 	 */
304 	nwl_dsi_write(dsi, NWL_DSI_VSYNC_POLARITY,
305 		      NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW);
306 	nwl_dsi_write(dsi, NWL_DSI_HSYNC_POLARITY,
307 		      NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW);
308 
309 	burst_mode = (dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_BURST) &&
310 		     !(dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE);
311 
312 	if (burst_mode) {
313 		nwl_dsi_write(dsi, NWL_DSI_VIDEO_MODE, NWL_DSI_VM_BURST_MODE);
314 		nwl_dsi_write(dsi, NWL_DSI_PIXEL_FIFO_SEND_LEVEL, 256);
315 	} else {
316 		mode = ((dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) ?
317 				NWL_DSI_VM_BURST_MODE_WITH_SYNC_PULSES :
318 				NWL_DSI_VM_NON_BURST_MODE_WITH_SYNC_EVENTS);
319 		nwl_dsi_write(dsi, NWL_DSI_VIDEO_MODE, mode);
320 		nwl_dsi_write(dsi, NWL_DSI_PIXEL_FIFO_SEND_LEVEL,
321 			      dsi->mode.hdisplay);
322 	}
323 
324 	nwl_dsi_write(dsi, NWL_DSI_HFP, hfront_porch);
325 	nwl_dsi_write(dsi, NWL_DSI_HBP, hback_porch);
326 	nwl_dsi_write(dsi, NWL_DSI_HSA, hsync_len);
327 
328 	nwl_dsi_write(dsi, NWL_DSI_ENABLE_MULT_PKTS, 0x0);
329 	nwl_dsi_write(dsi, NWL_DSI_BLLP_MODE, 0x1);
330 	nwl_dsi_write(dsi, NWL_DSI_USE_NULL_PKT_BLLP, 0x0);
331 	nwl_dsi_write(dsi, NWL_DSI_VC, 0x0);
332 
333 	nwl_dsi_write(dsi, NWL_DSI_PIXEL_PAYLOAD_SIZE, dsi->mode.hdisplay);
334 	nwl_dsi_write(dsi, NWL_DSI_VACTIVE, dsi->mode.vdisplay - 1);
335 	nwl_dsi_write(dsi, NWL_DSI_VBP, vback_porch);
336 	nwl_dsi_write(dsi, NWL_DSI_VFP, vfront_porch);
337 
338 	return nwl_dsi_clear_error(dsi);
339 }
340 
nwl_dsi_init_interrupts(struct nwl_dsi * dsi)341 static int nwl_dsi_init_interrupts(struct nwl_dsi *dsi)
342 {
343 	u32 irq_enable;
344 
345 	nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK, 0xffffffff);
346 	nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK2, 0x7);
347 
348 	irq_enable = ~(u32)(NWL_DSI_TX_PKT_DONE_MASK |
349 			    NWL_DSI_RX_PKT_HDR_RCVD_MASK |
350 			    NWL_DSI_TX_FIFO_OVFLW_MASK |
351 			    NWL_DSI_HS_TX_TIMEOUT_MASK);
352 
353 	nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK, irq_enable);
354 
355 	return nwl_dsi_clear_error(dsi);
356 }
357 
nwl_dsi_host_attach(struct mipi_dsi_host * dsi_host,struct mipi_dsi_device * device)358 static int nwl_dsi_host_attach(struct mipi_dsi_host *dsi_host,
359 			       struct mipi_dsi_device *device)
360 {
361 	struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
362 	struct device *dev = dsi->dev;
363 
364 	DRM_DEV_INFO(dev, "lanes=%u, format=0x%x flags=0x%lx\n", device->lanes,
365 		     device->format, device->mode_flags);
366 
367 	if (device->lanes < 1 || device->lanes > 4)
368 		return -EINVAL;
369 
370 	dsi->lanes = device->lanes;
371 	dsi->format = device->format;
372 	dsi->dsi_mode_flags = device->mode_flags;
373 
374 	return 0;
375 }
376 
nwl_dsi_read_packet(struct nwl_dsi * dsi,u32 status)377 static bool nwl_dsi_read_packet(struct nwl_dsi *dsi, u32 status)
378 {
379 	struct device *dev = dsi->dev;
380 	struct nwl_dsi_transfer *xfer = dsi->xfer;
381 	int err;
382 	u8 *payload = xfer->msg->rx_buf;
383 	u32 val;
384 	u16 word_count;
385 	u8 channel;
386 	u8 data_type;
387 
388 	xfer->status = 0;
389 
390 	if (xfer->rx_word_count == 0) {
391 		if (!(status & NWL_DSI_RX_PKT_HDR_RCVD))
392 			return false;
393 		/* Get the RX header and parse it */
394 		val = nwl_dsi_read(dsi, NWL_DSI_RX_PKT_HEADER);
395 		err = nwl_dsi_clear_error(dsi);
396 		if (err)
397 			xfer->status = err;
398 		word_count = NWL_DSI_WC(val);
399 		channel = NWL_DSI_RX_VC(val);
400 		data_type = NWL_DSI_RX_DT(val);
401 
402 		if (channel != xfer->msg->channel) {
403 			DRM_DEV_ERROR(dev,
404 				      "[%02X] Channel mismatch (%u != %u)\n",
405 				      xfer->cmd, channel, xfer->msg->channel);
406 			xfer->status = -EINVAL;
407 			return true;
408 		}
409 
410 		switch (data_type) {
411 		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
412 		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
413 			if (xfer->msg->rx_len > 1) {
414 				/* read second byte */
415 				payload[1] = word_count >> 8;
416 				++xfer->rx_len;
417 			}
418 			fallthrough;
419 		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
420 		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
421 			if (xfer->msg->rx_len > 0) {
422 				/* read first byte */
423 				payload[0] = word_count & 0xff;
424 				++xfer->rx_len;
425 			}
426 			xfer->status = xfer->rx_len;
427 			return true;
428 		case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
429 			word_count &= 0xff;
430 			DRM_DEV_ERROR(dev, "[%02X] DSI error report: 0x%02x\n",
431 				      xfer->cmd, word_count);
432 			xfer->status = -EPROTO;
433 			return true;
434 		}
435 
436 		if (word_count > xfer->msg->rx_len) {
437 			DRM_DEV_ERROR(dev,
438 				"[%02X] Receive buffer too small: %zu (< %u)\n",
439 				xfer->cmd, xfer->msg->rx_len, word_count);
440 			xfer->status = -EINVAL;
441 			return true;
442 		}
443 
444 		xfer->rx_word_count = word_count;
445 	} else {
446 		/* Set word_count from previous header read */
447 		word_count = xfer->rx_word_count;
448 	}
449 
450 	/* If RX payload is not yet received, wait for it */
451 	if (!(status & NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD))
452 		return false;
453 
454 	/* Read the RX payload */
455 	while (word_count >= 4) {
456 		val = nwl_dsi_read(dsi, NWL_DSI_RX_PAYLOAD);
457 		payload[0] = (val >> 0) & 0xff;
458 		payload[1] = (val >> 8) & 0xff;
459 		payload[2] = (val >> 16) & 0xff;
460 		payload[3] = (val >> 24) & 0xff;
461 		payload += 4;
462 		xfer->rx_len += 4;
463 		word_count -= 4;
464 	}
465 
466 	if (word_count > 0) {
467 		val = nwl_dsi_read(dsi, NWL_DSI_RX_PAYLOAD);
468 		switch (word_count) {
469 		case 3:
470 			payload[2] = (val >> 16) & 0xff;
471 			++xfer->rx_len;
472 			fallthrough;
473 		case 2:
474 			payload[1] = (val >> 8) & 0xff;
475 			++xfer->rx_len;
476 			fallthrough;
477 		case 1:
478 			payload[0] = (val >> 0) & 0xff;
479 			++xfer->rx_len;
480 			break;
481 		}
482 	}
483 
484 	xfer->status = xfer->rx_len;
485 	err = nwl_dsi_clear_error(dsi);
486 	if (err)
487 		xfer->status = err;
488 
489 	return true;
490 }
491 
nwl_dsi_finish_transmission(struct nwl_dsi * dsi,u32 status)492 static void nwl_dsi_finish_transmission(struct nwl_dsi *dsi, u32 status)
493 {
494 	struct nwl_dsi_transfer *xfer = dsi->xfer;
495 	bool end_packet = false;
496 
497 	if (!xfer)
498 		return;
499 
500 	if (xfer->direction == DSI_PACKET_SEND &&
501 	    status & NWL_DSI_TX_PKT_DONE) {
502 		xfer->status = xfer->tx_len;
503 		end_packet = true;
504 	} else if (status & NWL_DSI_DPHY_DIRECTION &&
505 		   ((status & (NWL_DSI_RX_PKT_HDR_RCVD |
506 			       NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)))) {
507 		end_packet = nwl_dsi_read_packet(dsi, status);
508 	}
509 
510 	if (end_packet)
511 		complete(&xfer->completed);
512 }
513 
nwl_dsi_begin_transmission(struct nwl_dsi * dsi)514 static void nwl_dsi_begin_transmission(struct nwl_dsi *dsi)
515 {
516 	struct nwl_dsi_transfer *xfer = dsi->xfer;
517 	struct mipi_dsi_packet *pkt = &xfer->packet;
518 	const u8 *payload;
519 	size_t length;
520 	u16 word_count;
521 	u8 hs_mode;
522 	u32 val;
523 	u32 hs_workaround = 0;
524 
525 	/* Send the payload, if any */
526 	length = pkt->payload_length;
527 	payload = pkt->payload;
528 
529 	while (length >= 4) {
530 		val = *(u32 *)payload;
531 		hs_workaround |= !(val & 0xFFFF00);
532 		nwl_dsi_write(dsi, NWL_DSI_TX_PAYLOAD, val);
533 		payload += 4;
534 		length -= 4;
535 	}
536 	/* Send the rest of the payload */
537 	val = 0;
538 	switch (length) {
539 	case 3:
540 		val |= payload[2] << 16;
541 		fallthrough;
542 	case 2:
543 		val |= payload[1] << 8;
544 		hs_workaround |= !(val & 0xFFFF00);
545 		fallthrough;
546 	case 1:
547 		val |= payload[0];
548 		nwl_dsi_write(dsi, NWL_DSI_TX_PAYLOAD, val);
549 		break;
550 	}
551 	xfer->tx_len = pkt->payload_length;
552 
553 	/*
554 	 * Send the header
555 	 * header[0] = Virtual Channel + Data Type
556 	 * header[1] = Word Count LSB (LP) or first param (SP)
557 	 * header[2] = Word Count MSB (LP) or second param (SP)
558 	 */
559 	word_count = pkt->header[1] | (pkt->header[2] << 8);
560 	if (hs_workaround && (dsi->quirks & E11418_HS_MODE_QUIRK)) {
561 		DRM_DEV_DEBUG_DRIVER(dsi->dev,
562 				     "Using hs mode workaround for cmd 0x%x\n",
563 				     xfer->cmd);
564 		hs_mode = 1;
565 	} else {
566 		hs_mode = (xfer->msg->flags & MIPI_DSI_MSG_USE_LPM) ? 0 : 1;
567 	}
568 	val = NWL_DSI_WC(word_count) | NWL_DSI_TX_VC(xfer->msg->channel) |
569 	      NWL_DSI_TX_DT(xfer->msg->type) | NWL_DSI_HS_SEL(hs_mode) |
570 	      NWL_DSI_BTA_TX(xfer->need_bta);
571 	nwl_dsi_write(dsi, NWL_DSI_PKT_CONTROL, val);
572 
573 	/* Send packet command */
574 	nwl_dsi_write(dsi, NWL_DSI_SEND_PACKET, 0x1);
575 }
576 
nwl_dsi_host_transfer(struct mipi_dsi_host * dsi_host,const struct mipi_dsi_msg * msg)577 static ssize_t nwl_dsi_host_transfer(struct mipi_dsi_host *dsi_host,
578 				     const struct mipi_dsi_msg *msg)
579 {
580 	struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
581 	struct nwl_dsi_transfer xfer;
582 	ssize_t ret = 0;
583 
584 	/* Create packet to be sent */
585 	dsi->xfer = &xfer;
586 	ret = mipi_dsi_create_packet(&xfer.packet, msg);
587 	if (ret < 0) {
588 		dsi->xfer = NULL;
589 		return ret;
590 	}
591 
592 	if ((msg->type & MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM ||
593 	     msg->type & MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM ||
594 	     msg->type & MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM ||
595 	     msg->type & MIPI_DSI_DCS_READ) &&
596 	    msg->rx_len > 0 && msg->rx_buf)
597 		xfer.direction = DSI_PACKET_RECEIVE;
598 	else
599 		xfer.direction = DSI_PACKET_SEND;
600 
601 	xfer.need_bta = (xfer.direction == DSI_PACKET_RECEIVE);
602 	xfer.need_bta |= (msg->flags & MIPI_DSI_MSG_REQ_ACK) ? 1 : 0;
603 	xfer.msg = msg;
604 	xfer.status = -ETIMEDOUT;
605 	xfer.rx_word_count = 0;
606 	xfer.rx_len = 0;
607 	xfer.cmd = 0x00;
608 	if (msg->tx_len > 0)
609 		xfer.cmd = ((u8 *)(msg->tx_buf))[0];
610 	init_completion(&xfer.completed);
611 
612 	ret = clk_prepare_enable(dsi->rx_esc_clk);
613 	if (ret < 0) {
614 		DRM_DEV_ERROR(dsi->dev, "Failed to enable rx_esc clk: %zd\n",
615 			      ret);
616 		return ret;
617 	}
618 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "Enabled rx_esc clk @%lu Hz\n",
619 			     clk_get_rate(dsi->rx_esc_clk));
620 
621 	/* Initiate the DSI packet transmision */
622 	nwl_dsi_begin_transmission(dsi);
623 
624 	if (!wait_for_completion_timeout(&xfer.completed,
625 					 NWL_DSI_MIPI_FIFO_TIMEOUT)) {
626 		DRM_DEV_ERROR(dsi_host->dev, "[%02X] DSI transfer timed out\n",
627 			      xfer.cmd);
628 		ret = -ETIMEDOUT;
629 	} else {
630 		ret = xfer.status;
631 	}
632 
633 	clk_disable_unprepare(dsi->rx_esc_clk);
634 
635 	return ret;
636 }
637 
638 static const struct mipi_dsi_host_ops nwl_dsi_host_ops = {
639 	.attach = nwl_dsi_host_attach,
640 	.transfer = nwl_dsi_host_transfer,
641 };
642 
nwl_dsi_irq_handler(int irq,void * data)643 static irqreturn_t nwl_dsi_irq_handler(int irq, void *data)
644 {
645 	u32 irq_status;
646 	struct nwl_dsi *dsi = data;
647 
648 	irq_status = nwl_dsi_read(dsi, NWL_DSI_IRQ_STATUS);
649 
650 	if (irq_status & NWL_DSI_TX_FIFO_OVFLW)
651 		DRM_DEV_ERROR_RATELIMITED(dsi->dev, "tx fifo overflow\n");
652 
653 	if (irq_status & NWL_DSI_HS_TX_TIMEOUT)
654 		DRM_DEV_ERROR_RATELIMITED(dsi->dev, "HS tx timeout\n");
655 
656 	if (irq_status & NWL_DSI_TX_PKT_DONE ||
657 	    irq_status & NWL_DSI_RX_PKT_HDR_RCVD ||
658 	    irq_status & NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)
659 		nwl_dsi_finish_transmission(dsi, irq_status);
660 
661 	return IRQ_HANDLED;
662 }
663 
nwl_dsi_enable(struct nwl_dsi * dsi)664 static int nwl_dsi_enable(struct nwl_dsi *dsi)
665 {
666 	struct device *dev = dsi->dev;
667 	union phy_configure_opts *phy_cfg = &dsi->phy_cfg;
668 	int ret;
669 
670 	if (!dsi->lanes) {
671 		DRM_DEV_ERROR(dev, "Need DSI lanes: %d\n", dsi->lanes);
672 		return -EINVAL;
673 	}
674 
675 	ret = phy_init(dsi->phy);
676 	if (ret < 0) {
677 		DRM_DEV_ERROR(dev, "Failed to init DSI phy: %d\n", ret);
678 		return ret;
679 	}
680 
681 	ret = phy_configure(dsi->phy, phy_cfg);
682 	if (ret < 0) {
683 		DRM_DEV_ERROR(dev, "Failed to configure DSI phy: %d\n", ret);
684 		goto uninit_phy;
685 	}
686 
687 	ret = clk_prepare_enable(dsi->tx_esc_clk);
688 	if (ret < 0) {
689 		DRM_DEV_ERROR(dsi->dev, "Failed to enable tx_esc clk: %d\n",
690 			      ret);
691 		goto uninit_phy;
692 	}
693 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "Enabled tx_esc clk @%lu Hz\n",
694 			     clk_get_rate(dsi->tx_esc_clk));
695 
696 	ret = nwl_dsi_config_host(dsi);
697 	if (ret < 0) {
698 		DRM_DEV_ERROR(dev, "Failed to set up DSI: %d", ret);
699 		goto disable_clock;
700 	}
701 
702 	ret = nwl_dsi_config_dpi(dsi);
703 	if (ret < 0) {
704 		DRM_DEV_ERROR(dev, "Failed to set up DPI: %d", ret);
705 		goto disable_clock;
706 	}
707 
708 	ret = phy_power_on(dsi->phy);
709 	if (ret < 0) {
710 		DRM_DEV_ERROR(dev, "Failed to power on DPHY (%d)\n", ret);
711 		goto disable_clock;
712 	}
713 
714 	ret = nwl_dsi_init_interrupts(dsi);
715 	if (ret < 0)
716 		goto power_off_phy;
717 
718 	return ret;
719 
720 power_off_phy:
721 	phy_power_off(dsi->phy);
722 disable_clock:
723 	clk_disable_unprepare(dsi->tx_esc_clk);
724 uninit_phy:
725 	phy_exit(dsi->phy);
726 
727 	return ret;
728 }
729 
nwl_dsi_disable(struct nwl_dsi * dsi)730 static int nwl_dsi_disable(struct nwl_dsi *dsi)
731 {
732 	struct device *dev = dsi->dev;
733 
734 	DRM_DEV_DEBUG_DRIVER(dev, "Disabling clocks and phy\n");
735 
736 	phy_power_off(dsi->phy);
737 	phy_exit(dsi->phy);
738 
739 	/* Disabling the clock before the phy breaks enabling dsi again */
740 	clk_disable_unprepare(dsi->tx_esc_clk);
741 
742 	return 0;
743 }
744 
nwl_dsi_bridge_disable(struct drm_bridge * bridge)745 static void nwl_dsi_bridge_disable(struct drm_bridge *bridge)
746 {
747 	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
748 	int ret;
749 
750 	nwl_dsi_disable(dsi);
751 
752 	ret = reset_control_assert(dsi->rst_dpi);
753 	if (ret < 0) {
754 		DRM_DEV_ERROR(dsi->dev, "Failed to assert DPI: %d\n", ret);
755 		return;
756 	}
757 	ret = reset_control_assert(dsi->rst_byte);
758 	if (ret < 0) {
759 		DRM_DEV_ERROR(dsi->dev, "Failed to assert ESC: %d\n", ret);
760 		return;
761 	}
762 	ret = reset_control_assert(dsi->rst_esc);
763 	if (ret < 0) {
764 		DRM_DEV_ERROR(dsi->dev, "Failed to assert BYTE: %d\n", ret);
765 		return;
766 	}
767 	ret = reset_control_assert(dsi->rst_pclk);
768 	if (ret < 0) {
769 		DRM_DEV_ERROR(dsi->dev, "Failed to assert PCLK: %d\n", ret);
770 		return;
771 	}
772 
773 	clk_disable_unprepare(dsi->core_clk);
774 	clk_disable_unprepare(dsi->lcdif_clk);
775 
776 	pm_runtime_put(dsi->dev);
777 }
778 
nwl_dsi_get_dphy_params(struct nwl_dsi * dsi,const struct drm_display_mode * mode,union phy_configure_opts * phy_opts)779 static int nwl_dsi_get_dphy_params(struct nwl_dsi *dsi,
780 				   const struct drm_display_mode *mode,
781 				   union phy_configure_opts *phy_opts)
782 {
783 	unsigned long rate;
784 	int ret;
785 
786 	if (dsi->lanes < 1 || dsi->lanes > 4)
787 		return -EINVAL;
788 
789 	/*
790 	 * So far the DPHY spec minimal timings work for both mixel
791 	 * dphy and nwl dsi host
792 	 */
793 	ret = phy_mipi_dphy_get_default_config(mode->clock * 1000,
794 		mipi_dsi_pixel_format_to_bpp(dsi->format), dsi->lanes,
795 		&phy_opts->mipi_dphy);
796 	if (ret < 0)
797 		return ret;
798 
799 	rate = clk_get_rate(dsi->tx_esc_clk);
800 	DRM_DEV_DEBUG_DRIVER(dsi->dev, "LP clk is @%lu Hz\n", rate);
801 	phy_opts->mipi_dphy.lp_clk_rate = rate;
802 
803 	return 0;
804 }
805 
nwl_dsi_bridge_mode_fixup(struct drm_bridge * bridge,const struct drm_display_mode * mode,struct drm_display_mode * adjusted_mode)806 static bool nwl_dsi_bridge_mode_fixup(struct drm_bridge *bridge,
807 				      const struct drm_display_mode *mode,
808 				      struct drm_display_mode *adjusted_mode)
809 {
810 	/* At least LCDIF + NWL needs active high sync */
811 	adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
812 	adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
813 
814 	return true;
815 }
816 
817 static enum drm_mode_status
nwl_dsi_bridge_mode_valid(struct drm_bridge * bridge,const struct drm_display_info * info,const struct drm_display_mode * mode)818 nwl_dsi_bridge_mode_valid(struct drm_bridge *bridge,
819 			  const struct drm_display_info *info,
820 			  const struct drm_display_mode *mode)
821 {
822 	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
823 	int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
824 
825 	if (mode->clock * bpp > 15000000 * dsi->lanes)
826 		return MODE_CLOCK_HIGH;
827 
828 	if (mode->clock * bpp < 80000 * dsi->lanes)
829 		return MODE_CLOCK_LOW;
830 
831 	return MODE_OK;
832 }
833 
834 static void
nwl_dsi_bridge_mode_set(struct drm_bridge * bridge,const struct drm_display_mode * mode,const struct drm_display_mode * adjusted_mode)835 nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
836 			const struct drm_display_mode *mode,
837 			const struct drm_display_mode *adjusted_mode)
838 {
839 	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
840 	struct device *dev = dsi->dev;
841 	union phy_configure_opts new_cfg;
842 	unsigned long phy_ref_rate;
843 	int ret;
844 
845 	ret = nwl_dsi_get_dphy_params(dsi, adjusted_mode, &new_cfg);
846 	if (ret < 0)
847 		return;
848 
849 	/*
850 	 * If hs clock is unchanged, we're all good - all parameters are
851 	 * derived from it atm.
852 	 */
853 	if (new_cfg.mipi_dphy.hs_clk_rate == dsi->phy_cfg.mipi_dphy.hs_clk_rate)
854 		return;
855 
856 	phy_ref_rate = clk_get_rate(dsi->phy_ref_clk);
857 	DRM_DEV_DEBUG_DRIVER(dev, "PHY at ref rate: %lu\n", phy_ref_rate);
858 	/* Save the new desired phy config */
859 	memcpy(&dsi->phy_cfg, &new_cfg, sizeof(new_cfg));
860 
861 	memcpy(&dsi->mode, adjusted_mode, sizeof(dsi->mode));
862 	drm_mode_debug_printmodeline(adjusted_mode);
863 }
864 
nwl_dsi_bridge_pre_enable(struct drm_bridge * bridge)865 static void nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge)
866 {
867 	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
868 	int ret;
869 
870 	pm_runtime_get_sync(dsi->dev);
871 
872 	if (clk_prepare_enable(dsi->lcdif_clk) < 0)
873 		return;
874 	if (clk_prepare_enable(dsi->core_clk) < 0)
875 		return;
876 
877 	/* Step 1 from DSI reset-out instructions */
878 	ret = reset_control_deassert(dsi->rst_pclk);
879 	if (ret < 0) {
880 		DRM_DEV_ERROR(dsi->dev, "Failed to deassert PCLK: %d\n", ret);
881 		return;
882 	}
883 
884 	/* Step 2 from DSI reset-out instructions */
885 	nwl_dsi_enable(dsi);
886 
887 	/* Step 3 from DSI reset-out instructions */
888 	ret = reset_control_deassert(dsi->rst_esc);
889 	if (ret < 0) {
890 		DRM_DEV_ERROR(dsi->dev, "Failed to deassert ESC: %d\n", ret);
891 		return;
892 	}
893 	ret = reset_control_deassert(dsi->rst_byte);
894 	if (ret < 0) {
895 		DRM_DEV_ERROR(dsi->dev, "Failed to deassert BYTE: %d\n", ret);
896 		return;
897 	}
898 }
899 
nwl_dsi_bridge_enable(struct drm_bridge * bridge)900 static void nwl_dsi_bridge_enable(struct drm_bridge *bridge)
901 {
902 	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
903 	int ret;
904 
905 	/* Step 5 from DSI reset-out instructions */
906 	ret = reset_control_deassert(dsi->rst_dpi);
907 	if (ret < 0)
908 		DRM_DEV_ERROR(dsi->dev, "Failed to deassert DPI: %d\n", ret);
909 }
910 
nwl_dsi_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)911 static int nwl_dsi_bridge_attach(struct drm_bridge *bridge,
912 				 enum drm_bridge_attach_flags flags)
913 {
914 	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
915 	struct drm_bridge *panel_bridge;
916 	struct drm_panel *panel;
917 	int ret;
918 
919 	ret = drm_of_find_panel_or_bridge(dsi->dev->of_node, 1, 0, &panel,
920 					  &panel_bridge);
921 	if (ret)
922 		return ret;
923 
924 	if (panel) {
925 		panel_bridge = drm_panel_bridge_add(panel);
926 		if (IS_ERR(panel_bridge))
927 			return PTR_ERR(panel_bridge);
928 	}
929 	dsi->panel_bridge = panel_bridge;
930 
931 	if (!dsi->panel_bridge)
932 		return -EPROBE_DEFER;
933 
934 	return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, bridge,
935 				 flags);
936 }
937 
nwl_dsi_bridge_detach(struct drm_bridge * bridge)938 static void nwl_dsi_bridge_detach(struct drm_bridge *bridge)
939 {	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
940 
941 	drm_of_panel_bridge_remove(dsi->dev->of_node, 1, 0);
942 }
943 
944 static const struct drm_bridge_funcs nwl_dsi_bridge_funcs = {
945 	.pre_enable = nwl_dsi_bridge_pre_enable,
946 	.enable     = nwl_dsi_bridge_enable,
947 	.disable    = nwl_dsi_bridge_disable,
948 	.mode_fixup = nwl_dsi_bridge_mode_fixup,
949 	.mode_set   = nwl_dsi_bridge_mode_set,
950 	.mode_valid = nwl_dsi_bridge_mode_valid,
951 	.attach	    = nwl_dsi_bridge_attach,
952 	.detach	    = nwl_dsi_bridge_detach,
953 };
954 
nwl_dsi_parse_dt(struct nwl_dsi * dsi)955 static int nwl_dsi_parse_dt(struct nwl_dsi *dsi)
956 {
957 	struct platform_device *pdev = to_platform_device(dsi->dev);
958 	struct clk *clk;
959 	void __iomem *base;
960 	int ret;
961 
962 	dsi->phy = devm_phy_get(dsi->dev, "dphy");
963 	if (IS_ERR(dsi->phy)) {
964 		ret = PTR_ERR(dsi->phy);
965 		if (ret != -EPROBE_DEFER)
966 			DRM_DEV_ERROR(dsi->dev, "Could not get PHY: %d\n", ret);
967 		return ret;
968 	}
969 
970 	clk = devm_clk_get(dsi->dev, "lcdif");
971 	if (IS_ERR(clk)) {
972 		ret = PTR_ERR(clk);
973 		DRM_DEV_ERROR(dsi->dev, "Failed to get lcdif clock: %d\n",
974 			      ret);
975 		return ret;
976 	}
977 	dsi->lcdif_clk = clk;
978 
979 	clk = devm_clk_get(dsi->dev, "core");
980 	if (IS_ERR(clk)) {
981 		ret = PTR_ERR(clk);
982 		DRM_DEV_ERROR(dsi->dev, "Failed to get core clock: %d\n",
983 			      ret);
984 		return ret;
985 	}
986 	dsi->core_clk = clk;
987 
988 	clk = devm_clk_get(dsi->dev, "phy_ref");
989 	if (IS_ERR(clk)) {
990 		ret = PTR_ERR(clk);
991 		DRM_DEV_ERROR(dsi->dev, "Failed to get phy_ref clock: %d\n",
992 			      ret);
993 		return ret;
994 	}
995 	dsi->phy_ref_clk = clk;
996 
997 	clk = devm_clk_get(dsi->dev, "rx_esc");
998 	if (IS_ERR(clk)) {
999 		ret = PTR_ERR(clk);
1000 		DRM_DEV_ERROR(dsi->dev, "Failed to get rx_esc clock: %d\n",
1001 			      ret);
1002 		return ret;
1003 	}
1004 	dsi->rx_esc_clk = clk;
1005 
1006 	clk = devm_clk_get(dsi->dev, "tx_esc");
1007 	if (IS_ERR(clk)) {
1008 		ret = PTR_ERR(clk);
1009 		DRM_DEV_ERROR(dsi->dev, "Failed to get tx_esc clock: %d\n",
1010 			      ret);
1011 		return ret;
1012 	}
1013 	dsi->tx_esc_clk = clk;
1014 
1015 	dsi->mux = devm_mux_control_get(dsi->dev, NULL);
1016 	if (IS_ERR(dsi->mux)) {
1017 		ret = PTR_ERR(dsi->mux);
1018 		if (ret != -EPROBE_DEFER)
1019 			DRM_DEV_ERROR(dsi->dev, "Failed to get mux: %d\n", ret);
1020 		return ret;
1021 	}
1022 
1023 	base = devm_platform_ioremap_resource(pdev, 0);
1024 	if (IS_ERR(base))
1025 		return PTR_ERR(base);
1026 
1027 	dsi->regmap =
1028 		devm_regmap_init_mmio(dsi->dev, base, &nwl_dsi_regmap_config);
1029 	if (IS_ERR(dsi->regmap)) {
1030 		ret = PTR_ERR(dsi->regmap);
1031 		DRM_DEV_ERROR(dsi->dev, "Failed to create NWL DSI regmap: %d\n",
1032 			      ret);
1033 		return ret;
1034 	}
1035 
1036 	dsi->irq = platform_get_irq(pdev, 0);
1037 	if (dsi->irq < 0) {
1038 		DRM_DEV_ERROR(dsi->dev, "Failed to get device IRQ: %d\n",
1039 			      dsi->irq);
1040 		return dsi->irq;
1041 	}
1042 
1043 	dsi->rst_pclk = devm_reset_control_get_exclusive(dsi->dev, "pclk");
1044 	if (IS_ERR(dsi->rst_pclk)) {
1045 		DRM_DEV_ERROR(dsi->dev, "Failed to get pclk reset: %ld\n",
1046 			      PTR_ERR(dsi->rst_pclk));
1047 		return PTR_ERR(dsi->rst_pclk);
1048 	}
1049 	dsi->rst_byte = devm_reset_control_get_exclusive(dsi->dev, "byte");
1050 	if (IS_ERR(dsi->rst_byte)) {
1051 		DRM_DEV_ERROR(dsi->dev, "Failed to get byte reset: %ld\n",
1052 			      PTR_ERR(dsi->rst_byte));
1053 		return PTR_ERR(dsi->rst_byte);
1054 	}
1055 	dsi->rst_esc = devm_reset_control_get_exclusive(dsi->dev, "esc");
1056 	if (IS_ERR(dsi->rst_esc)) {
1057 		DRM_DEV_ERROR(dsi->dev, "Failed to get esc reset: %ld\n",
1058 			      PTR_ERR(dsi->rst_esc));
1059 		return PTR_ERR(dsi->rst_esc);
1060 	}
1061 	dsi->rst_dpi = devm_reset_control_get_exclusive(dsi->dev, "dpi");
1062 	if (IS_ERR(dsi->rst_dpi)) {
1063 		DRM_DEV_ERROR(dsi->dev, "Failed to get dpi reset: %ld\n",
1064 			      PTR_ERR(dsi->rst_dpi));
1065 		return PTR_ERR(dsi->rst_dpi);
1066 	}
1067 	return 0;
1068 }
1069 
nwl_dsi_select_input(struct nwl_dsi * dsi)1070 static int nwl_dsi_select_input(struct nwl_dsi *dsi)
1071 {
1072 	struct device_node *remote;
1073 	u32 use_dcss = 1;
1074 	int ret;
1075 
1076 	remote = of_graph_get_remote_node(dsi->dev->of_node, 0,
1077 					  NWL_DSI_ENDPOINT_LCDIF);
1078 	if (remote) {
1079 		use_dcss = 0;
1080 	} else {
1081 		remote = of_graph_get_remote_node(dsi->dev->of_node, 0,
1082 						  NWL_DSI_ENDPOINT_DCSS);
1083 		if (!remote) {
1084 			DRM_DEV_ERROR(dsi->dev,
1085 				      "No valid input endpoint found\n");
1086 			return -EINVAL;
1087 		}
1088 	}
1089 
1090 	DRM_DEV_INFO(dsi->dev, "Using %s as input source\n",
1091 		     (use_dcss) ? "DCSS" : "LCDIF");
1092 	ret = mux_control_try_select(dsi->mux, use_dcss);
1093 	if (ret < 0)
1094 		DRM_DEV_ERROR(dsi->dev, "Failed to select input: %d\n", ret);
1095 
1096 	of_node_put(remote);
1097 	return ret;
1098 }
1099 
nwl_dsi_deselect_input(struct nwl_dsi * dsi)1100 static int nwl_dsi_deselect_input(struct nwl_dsi *dsi)
1101 {
1102 	int ret;
1103 
1104 	ret = mux_control_deselect(dsi->mux);
1105 	if (ret < 0)
1106 		DRM_DEV_ERROR(dsi->dev, "Failed to deselect input: %d\n", ret);
1107 
1108 	return ret;
1109 }
1110 
1111 static const struct drm_bridge_timings nwl_dsi_timings = {
1112 	.input_bus_flags = DRM_BUS_FLAG_DE_LOW,
1113 };
1114 
1115 static const struct of_device_id nwl_dsi_dt_ids[] = {
1116 	{ .compatible = "fsl,imx8mq-nwl-dsi", },
1117 	{ /* sentinel */ }
1118 };
1119 MODULE_DEVICE_TABLE(of, nwl_dsi_dt_ids);
1120 
1121 static const struct soc_device_attribute nwl_dsi_quirks_match[] = {
1122 	{ .soc_id = "i.MX8MQ", .revision = "2.0",
1123 	  .data = (void *)E11418_HS_MODE_QUIRK },
1124 	{ /* sentinel. */ },
1125 };
1126 
nwl_dsi_probe(struct platform_device * pdev)1127 static int nwl_dsi_probe(struct platform_device *pdev)
1128 {
1129 	struct device *dev = &pdev->dev;
1130 	const struct soc_device_attribute *attr;
1131 	struct nwl_dsi *dsi;
1132 	int ret;
1133 
1134 	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
1135 	if (!dsi)
1136 		return -ENOMEM;
1137 
1138 	dsi->dev = dev;
1139 
1140 	ret = nwl_dsi_parse_dt(dsi);
1141 	if (ret)
1142 		return ret;
1143 
1144 	ret = devm_request_irq(dev, dsi->irq, nwl_dsi_irq_handler, 0,
1145 			       dev_name(dev), dsi);
1146 	if (ret < 0) {
1147 		DRM_DEV_ERROR(dev, "Failed to request IRQ %d: %d\n", dsi->irq,
1148 			      ret);
1149 		return ret;
1150 	}
1151 
1152 	dsi->dsi_host.ops = &nwl_dsi_host_ops;
1153 	dsi->dsi_host.dev = dev;
1154 	ret = mipi_dsi_host_register(&dsi->dsi_host);
1155 	if (ret) {
1156 		DRM_DEV_ERROR(dev, "Failed to register MIPI host: %d\n", ret);
1157 		return ret;
1158 	}
1159 
1160 	attr = soc_device_match(nwl_dsi_quirks_match);
1161 	if (attr)
1162 		dsi->quirks = (uintptr_t)attr->data;
1163 
1164 	dsi->bridge.driver_private = dsi;
1165 	dsi->bridge.funcs = &nwl_dsi_bridge_funcs;
1166 	dsi->bridge.of_node = dev->of_node;
1167 	dsi->bridge.timings = &nwl_dsi_timings;
1168 
1169 	dev_set_drvdata(dev, dsi);
1170 	pm_runtime_enable(dev);
1171 
1172 	ret = nwl_dsi_select_input(dsi);
1173 	if (ret < 0) {
1174 		mipi_dsi_host_unregister(&dsi->dsi_host);
1175 		return ret;
1176 	}
1177 
1178 	drm_bridge_add(&dsi->bridge);
1179 	return 0;
1180 }
1181 
nwl_dsi_remove(struct platform_device * pdev)1182 static int nwl_dsi_remove(struct platform_device *pdev)
1183 {
1184 	struct nwl_dsi *dsi = platform_get_drvdata(pdev);
1185 
1186 	nwl_dsi_deselect_input(dsi);
1187 	mipi_dsi_host_unregister(&dsi->dsi_host);
1188 	drm_bridge_remove(&dsi->bridge);
1189 	pm_runtime_disable(&pdev->dev);
1190 	return 0;
1191 }
1192 
1193 static struct platform_driver nwl_dsi_driver = {
1194 	.probe		= nwl_dsi_probe,
1195 	.remove		= nwl_dsi_remove,
1196 	.driver		= {
1197 		.of_match_table = nwl_dsi_dt_ids,
1198 		.name	= DRV_NAME,
1199 	},
1200 };
1201 
1202 module_platform_driver(nwl_dsi_driver);
1203 
1204 MODULE_AUTHOR("NXP Semiconductor");
1205 MODULE_AUTHOR("Purism SPC");
1206 MODULE_DESCRIPTION("Northwest Logic MIPI-DSI driver");
1207 MODULE_LICENSE("GPL"); /* GPLv2 or later */
1208