1/*
2 * Copyright © 2008 Keith Packard
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission.  The copyright holders make no representations
11 * about the suitability of this software for any purpose.  It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#ifndef _DRM_DP_HELPER_H_
24#define _DRM_DP_HELPER_H_
25
26#include <linux/delay.h>
27#include <linux/i2c.h>
28
29#include <drm/display/drm_dp.h>
30#include <drm/drm_connector.h>
31
32struct drm_device;
33struct drm_dp_aux;
34struct drm_panel;
35
36bool drm_dp_channel_eq_ok(const u8 link_status[DP_LINK_STATUS_SIZE],
37			  int lane_count);
38bool drm_dp_clock_recovery_ok(const u8 link_status[DP_LINK_STATUS_SIZE],
39			      int lane_count);
40u8 drm_dp_get_adjust_request_voltage(const u8 link_status[DP_LINK_STATUS_SIZE],
41				     int lane);
42u8 drm_dp_get_adjust_request_pre_emphasis(const u8 link_status[DP_LINK_STATUS_SIZE],
43					  int lane);
44u8 drm_dp_get_adjust_tx_ffe_preset(const u8 link_status[DP_LINK_STATUS_SIZE],
45				   int lane);
46
47int drm_dp_read_clock_recovery_delay(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE],
48				     enum drm_dp_phy dp_phy, bool uhbr);
49int drm_dp_read_channel_eq_delay(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE],
50				 enum drm_dp_phy dp_phy, bool uhbr);
51
52void drm_dp_link_train_clock_recovery_delay(const struct drm_dp_aux *aux,
53					    const u8 dpcd[DP_RECEIVER_CAP_SIZE]);
54void drm_dp_lttpr_link_train_clock_recovery_delay(void);
55void drm_dp_link_train_channel_eq_delay(const struct drm_dp_aux *aux,
56					const u8 dpcd[DP_RECEIVER_CAP_SIZE]);
57void drm_dp_lttpr_link_train_channel_eq_delay(const struct drm_dp_aux *aux,
58					      const u8 caps[DP_LTTPR_PHY_CAP_SIZE]);
59
60int drm_dp_128b132b_read_aux_rd_interval(struct drm_dp_aux *aux);
61bool drm_dp_128b132b_lane_channel_eq_done(const u8 link_status[DP_LINK_STATUS_SIZE],
62					  int lane_count);
63bool drm_dp_128b132b_lane_symbol_locked(const u8 link_status[DP_LINK_STATUS_SIZE],
64					int lane_count);
65bool drm_dp_128b132b_eq_interlane_align_done(const u8 link_status[DP_LINK_STATUS_SIZE]);
66bool drm_dp_128b132b_cds_interlane_align_done(const u8 link_status[DP_LINK_STATUS_SIZE]);
67bool drm_dp_128b132b_link_training_failed(const u8 link_status[DP_LINK_STATUS_SIZE]);
68
69u8 drm_dp_link_rate_to_bw_code(int link_rate);
70int drm_dp_bw_code_to_link_rate(u8 link_bw);
71
72const char *drm_dp_phy_name(enum drm_dp_phy dp_phy);
73
74/**
75 * struct drm_dp_vsc_sdp - drm DP VSC SDP
76 *
77 * This structure represents a DP VSC SDP of drm
78 * It is based on DP 1.4 spec [Table 2-116: VSC SDP Header Bytes] and
79 * [Table 2-117: VSC SDP Payload for DB16 through DB18]
80 *
81 * @sdp_type: secondary-data packet type
82 * @revision: revision number
83 * @length: number of valid data bytes
84 * @pixelformat: pixel encoding format
85 * @colorimetry: colorimetry format
86 * @bpc: bit per color
87 * @dynamic_range: dynamic range information
88 * @content_type: CTA-861-G defines content types and expected processing by a sink device
89 */
90struct drm_dp_vsc_sdp {
91	unsigned char sdp_type;
92	unsigned char revision;
93	unsigned char length;
94	enum dp_pixelformat pixelformat;
95	enum dp_colorimetry colorimetry;
96	int bpc;
97	enum dp_dynamic_range dynamic_range;
98	enum dp_content_type content_type;
99};
100
101void drm_dp_vsc_sdp_log(const char *level, struct device *dev,
102			const struct drm_dp_vsc_sdp *vsc);
103
104int drm_dp_psr_setup_time(const u8 psr_cap[EDP_PSR_RECEIVER_CAP_SIZE]);
105
106static inline int
107drm_dp_max_link_rate(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
108{
109	return drm_dp_bw_code_to_link_rate(dpcd[DP_MAX_LINK_RATE]);
110}
111
112static inline u8
113drm_dp_max_lane_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
114{
115	return dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
116}
117
118static inline bool
119drm_dp_enhanced_frame_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
120{
121	return dpcd[DP_DPCD_REV] >= 0x11 &&
122		(dpcd[DP_MAX_LANE_COUNT] & DP_ENHANCED_FRAME_CAP);
123}
124
125static inline bool
126drm_dp_fast_training_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
127{
128	return dpcd[DP_DPCD_REV] >= 0x11 &&
129		(dpcd[DP_MAX_DOWNSPREAD] & DP_NO_AUX_HANDSHAKE_LINK_TRAINING);
130}
131
132static inline bool
133drm_dp_tps3_supported(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
134{
135	return dpcd[DP_DPCD_REV] >= 0x12 &&
136		dpcd[DP_MAX_LANE_COUNT] & DP_TPS3_SUPPORTED;
137}
138
139static inline bool
140drm_dp_max_downspread(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
141{
142	return dpcd[DP_DPCD_REV] >= 0x11 ||
143		dpcd[DP_MAX_DOWNSPREAD] & DP_MAX_DOWNSPREAD_0_5;
144}
145
146static inline bool
147drm_dp_tps4_supported(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
148{
149	return dpcd[DP_DPCD_REV] >= 0x14 &&
150		dpcd[DP_MAX_DOWNSPREAD] & DP_TPS4_SUPPORTED;
151}
152
153static inline u8
154drm_dp_training_pattern_mask(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
155{
156	return (dpcd[DP_DPCD_REV] >= 0x14) ? DP_TRAINING_PATTERN_MASK_1_4 :
157		DP_TRAINING_PATTERN_MASK;
158}
159
160static inline bool
161drm_dp_is_branch(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
162{
163	return dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT;
164}
165
166/* DP/eDP DSC support */
167u8 drm_dp_dsc_sink_max_slice_count(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE],
168				   bool is_edp);
169u8 drm_dp_dsc_sink_line_buf_depth(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE]);
170int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpc[DP_DSC_RECEIVER_CAP_SIZE],
171					 u8 dsc_bpc[3]);
172
173static inline bool
174drm_dp_sink_supports_dsc(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE])
175{
176	return dsc_dpcd[DP_DSC_SUPPORT - DP_DSC_SUPPORT] &
177		DP_DSC_DECOMPRESSION_IS_SUPPORTED;
178}
179
180static inline u16
181drm_edp_dsc_sink_output_bpp(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE])
182{
183	return dsc_dpcd[DP_DSC_MAX_BITS_PER_PIXEL_LOW - DP_DSC_SUPPORT] |
184		((dsc_dpcd[DP_DSC_MAX_BITS_PER_PIXEL_HI - DP_DSC_SUPPORT] &
185		  DP_DSC_MAX_BITS_PER_PIXEL_HI_MASK) << 8);
186}
187
188static inline u32
189drm_dp_dsc_sink_max_slice_width(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE])
190{
191	/* Max Slicewidth = Number of Pixels * 320 */
192	return dsc_dpcd[DP_DSC_MAX_SLICE_WIDTH - DP_DSC_SUPPORT] *
193		DP_DSC_SLICE_WIDTH_MULTIPLIER;
194}
195
196/**
197 * drm_dp_dsc_sink_supports_format() - check if sink supports DSC with given output format
198 * @dsc_dpcd : DSC-capability DPCDs of the sink
199 * @output_format: output_format which is to be checked
200 *
201 * Returns true if the sink supports DSC with the given output_format, false otherwise.
202 */
203static inline bool
204drm_dp_dsc_sink_supports_format(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE], u8 output_format)
205{
206	return dsc_dpcd[DP_DSC_DEC_COLOR_FORMAT_CAP - DP_DSC_SUPPORT] & output_format;
207}
208
209/* Forward Error Correction Support on DP 1.4 */
210static inline bool
211drm_dp_sink_supports_fec(const u8 fec_capable)
212{
213	return fec_capable & DP_FEC_CAPABLE;
214}
215
216static inline bool
217drm_dp_channel_coding_supported(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
218{
219	return dpcd[DP_MAIN_LINK_CHANNEL_CODING] & DP_CAP_ANSI_8B10B;
220}
221
222static inline bool
223drm_dp_alternate_scrambler_reset_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
224{
225	return dpcd[DP_EDP_CONFIGURATION_CAP] &
226			DP_ALTERNATE_SCRAMBLER_RESET_CAP;
227}
228
229/* Ignore MSA timing for Adaptive Sync support on DP 1.4 */
230static inline bool
231drm_dp_sink_can_do_video_without_timing_msa(const u8 dpcd[DP_RECEIVER_CAP_SIZE])
232{
233	return dpcd[DP_DOWN_STREAM_PORT_COUNT] &
234		DP_MSA_TIMING_PAR_IGNORED;
235}
236
237/**
238 * drm_edp_backlight_supported() - Check an eDP DPCD for VESA backlight support
239 * @edp_dpcd: The DPCD to check
240 *
241 * Note that currently this function will return %false for panels which support various DPCD
242 * backlight features but which require the brightness be set through PWM, and don't support setting
243 * the brightness level via the DPCD.
244 *
245 * Returns: %True if @edp_dpcd indicates that VESA backlight controls are supported, %false
246 * otherwise
247 */
248static inline bool
249drm_edp_backlight_supported(const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE])
250{
251	return !!(edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP);
252}
253
254/*
255 * DisplayPort AUX channel
256 */
257
258/**
259 * struct drm_dp_aux_msg - DisplayPort AUX channel transaction
260 * @address: address of the (first) register to access
261 * @request: contains the type of transaction (see DP_AUX_* macros)
262 * @reply: upon completion, contains the reply type of the transaction
263 * @buffer: pointer to a transmission or reception buffer
264 * @size: size of @buffer
265 */
266struct drm_dp_aux_msg {
267	unsigned int address;
268	u8 request;
269	u8 reply;
270	void *buffer;
271	size_t size;
272};
273
274struct cec_adapter;
275struct edid;
276struct drm_connector;
277
278/**
279 * struct drm_dp_aux_cec - DisplayPort CEC-Tunneling-over-AUX
280 * @lock: mutex protecting this struct
281 * @adap: the CEC adapter for CEC-Tunneling-over-AUX support.
282 * @connector: the connector this CEC adapter is associated with
283 * @unregister_work: unregister the CEC adapter
284 */
285struct drm_dp_aux_cec {
286	struct mutex lock;
287	struct cec_adapter *adap;
288	struct drm_connector *connector;
289	struct delayed_work unregister_work;
290};
291
292/**
293 * struct drm_dp_aux - DisplayPort AUX channel
294 *
295 * An AUX channel can also be used to transport I2C messages to a sink. A
296 * typical application of that is to access an EDID that's present in the sink
297 * device. The @transfer() function can also be used to execute such
298 * transactions. The drm_dp_aux_register() function registers an I2C adapter
299 * that can be passed to drm_probe_ddc(). Upon removal, drivers should call
300 * drm_dp_aux_unregister() to remove the I2C adapter. The I2C adapter uses long
301 * transfers by default; if a partial response is received, the adapter will
302 * drop down to the size given by the partial response for this transaction
303 * only.
304 */
305struct drm_dp_aux {
306	/**
307	 * @name: user-visible name of this AUX channel and the
308	 * I2C-over-AUX adapter.
309	 *
310	 * It's also used to specify the name of the I2C adapter. If set
311	 * to %NULL, dev_name() of @dev will be used.
312	 */
313	const char *name;
314
315	/**
316	 * @ddc: I2C adapter that can be used for I2C-over-AUX
317	 * communication
318	 */
319	struct i2c_adapter ddc;
320
321	/**
322	 * @dev: pointer to struct device that is the parent for this
323	 * AUX channel.
324	 */
325	struct device *dev;
326
327	/**
328	 * @drm_dev: pointer to the &drm_device that owns this AUX channel.
329	 * Beware, this may be %NULL before drm_dp_aux_register() has been
330	 * called.
331	 *
332	 * It should be set to the &drm_device that will be using this AUX
333	 * channel as early as possible. For many graphics drivers this should
334	 * happen before drm_dp_aux_init(), however it's perfectly fine to set
335	 * this field later so long as it's assigned before calling
336	 * drm_dp_aux_register().
337	 */
338	struct drm_device *drm_dev;
339
340	/**
341	 * @crtc: backpointer to the crtc that is currently using this
342	 * AUX channel
343	 */
344	struct drm_crtc *crtc;
345
346	/**
347	 * @hw_mutex: internal mutex used for locking transfers.
348	 *
349	 * Note that if the underlying hardware is shared among multiple
350	 * channels, the driver needs to do additional locking to
351	 * prevent concurrent access.
352	 */
353	struct mutex hw_mutex;
354
355	/**
356	 * @crc_work: worker that captures CRCs for each frame
357	 */
358	struct work_struct crc_work;
359
360	/**
361	 * @crc_count: counter of captured frame CRCs
362	 */
363	u8 crc_count;
364
365	/**
366	 * @transfer: transfers a message representing a single AUX
367	 * transaction.
368	 *
369	 * This is a hardware-specific implementation of how
370	 * transactions are executed that the drivers must provide.
371	 *
372	 * A pointer to a &drm_dp_aux_msg structure describing the
373	 * transaction is passed into this function. Upon success, the
374	 * implementation should return the number of payload bytes that
375	 * were transferred, or a negative error-code on failure.
376	 *
377	 * Helpers will propagate these errors, with the exception of
378	 * the %-EBUSY error, which causes a transaction to be retried.
379	 * On a short, helpers will return %-EPROTO to make it simpler
380	 * to check for failure.
381	 *
382	 * The @transfer() function must only modify the reply field of
383	 * the &drm_dp_aux_msg structure. The retry logic and i2c
384	 * helpers assume this is the case.
385	 *
386	 * Also note that this callback can be called no matter the
387	 * state @dev is in and also no matter what state the panel is
388	 * in. It's expected:
389	 *
390	 * - If the @dev providing the AUX bus is currently unpowered then
391	 *   it will power itself up for the transfer.
392	 *
393	 * - If we're on eDP (using a drm_panel) and the panel is not in a
394	 *   state where it can respond (it's not powered or it's in a
395	 *   low power state) then this function may return an error, but
396	 *   not crash. It's up to the caller of this code to make sure that
397	 *   the panel is powered on if getting an error back is not OK. If a
398	 *   drm_panel driver is initiating a DP AUX transfer it may power
399	 *   itself up however it wants. All other code should ensure that
400	 *   the pre_enable() bridge chain (which eventually calls the
401	 *   drm_panel prepare function) has powered the panel.
402	 */
403	ssize_t (*transfer)(struct drm_dp_aux *aux,
404			    struct drm_dp_aux_msg *msg);
405
406	/**
407	 * @wait_hpd_asserted: wait for HPD to be asserted
408	 *
409	 * This is mainly useful for eDP panels drivers to wait for an eDP
410	 * panel to finish powering on. This is an optional function.
411	 *
412	 * This function will efficiently wait for the HPD signal to be
413	 * asserted. The `wait_us` parameter that is passed in says that we
414	 * know that the HPD signal is expected to be asserted within `wait_us`
415	 * microseconds. This function could wait for longer than `wait_us` if
416	 * the logic in the DP controller has a long debouncing time. The
417	 * important thing is that if this function returns success that the
418	 * DP controller is ready to send AUX transactions.
419	 *
420	 * This function returns 0 if HPD was asserted or -ETIMEDOUT if time
421	 * expired and HPD wasn't asserted. This function should not print
422	 * timeout errors to the log.
423	 *
424	 * The semantics of this function are designed to match the
425	 * readx_poll_timeout() function. That means a `wait_us` of 0 means
426	 * to wait forever. Like readx_poll_timeout(), this function may sleep.
427	 *
428	 * NOTE: this function specifically reports the state of the HPD pin
429	 * that's associated with the DP AUX channel. This is different from
430	 * the HPD concept in much of the rest of DRM which is more about
431	 * physical presence of a display. For eDP, for instance, a display is
432	 * assumed always present even if the HPD pin is deasserted.
433	 */
434	int (*wait_hpd_asserted)(struct drm_dp_aux *aux, unsigned long wait_us);
435
436	/**
437	 * @i2c_nack_count: Counts I2C NACKs, used for DP validation.
438	 */
439	unsigned i2c_nack_count;
440	/**
441	 * @i2c_defer_count: Counts I2C DEFERs, used for DP validation.
442	 */
443	unsigned i2c_defer_count;
444	/**
445	 * @cec: struct containing fields used for CEC-Tunneling-over-AUX.
446	 */
447	struct drm_dp_aux_cec cec;
448	/**
449	 * @is_remote: Is this AUX CH actually using sideband messaging.
450	 */
451	bool is_remote;
452};
453
454int drm_dp_dpcd_probe(struct drm_dp_aux *aux, unsigned int offset);
455ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset,
456			 void *buffer, size_t size);
457ssize_t drm_dp_dpcd_write(struct drm_dp_aux *aux, unsigned int offset,
458			  void *buffer, size_t size);
459
460/**
461 * drm_dp_dpcd_readb() - read a single byte from the DPCD
462 * @aux: DisplayPort AUX channel
463 * @offset: address of the register to read
464 * @valuep: location where the value of the register will be stored
465 *
466 * Returns the number of bytes transferred (1) on success, or a negative
467 * error code on failure.
468 */
469static inline ssize_t drm_dp_dpcd_readb(struct drm_dp_aux *aux,
470					unsigned int offset, u8 *valuep)
471{
472	return drm_dp_dpcd_read(aux, offset, valuep, 1);
473}
474
475/**
476 * drm_dp_dpcd_writeb() - write a single byte to the DPCD
477 * @aux: DisplayPort AUX channel
478 * @offset: address of the register to write
479 * @value: value to write to the register
480 *
481 * Returns the number of bytes transferred (1) on success, or a negative
482 * error code on failure.
483 */
484static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux,
485					 unsigned int offset, u8 value)
486{
487	return drm_dp_dpcd_write(aux, offset, &value, 1);
488}
489
490int drm_dp_read_dpcd_caps(struct drm_dp_aux *aux,
491			  u8 dpcd[DP_RECEIVER_CAP_SIZE]);
492
493int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
494				 u8 status[DP_LINK_STATUS_SIZE]);
495
496int drm_dp_dpcd_read_phy_link_status(struct drm_dp_aux *aux,
497				     enum drm_dp_phy dp_phy,
498				     u8 link_status[DP_LINK_STATUS_SIZE]);
499
500bool drm_dp_send_real_edid_checksum(struct drm_dp_aux *aux,
501				    u8 real_edid_checksum);
502
503int drm_dp_read_downstream_info(struct drm_dp_aux *aux,
504				const u8 dpcd[DP_RECEIVER_CAP_SIZE],
505				u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS]);
506bool drm_dp_downstream_is_type(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
507			       const u8 port_cap[4], u8 type);
508bool drm_dp_downstream_is_tmds(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
509			       const u8 port_cap[4],
510			       const struct edid *edid);
511int drm_dp_downstream_max_dotclock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
512				   const u8 port_cap[4]);
513int drm_dp_downstream_max_tmds_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
514				     const u8 port_cap[4],
515				     const struct edid *edid);
516int drm_dp_downstream_min_tmds_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
517				     const u8 port_cap[4],
518				     const struct edid *edid);
519int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
520			      const u8 port_cap[4],
521			      const struct edid *edid);
522bool drm_dp_downstream_420_passthrough(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
523				       const u8 port_cap[4]);
524bool drm_dp_downstream_444_to_420_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
525					     const u8 port_cap[4]);
526struct drm_display_mode *drm_dp_downstream_mode(struct drm_device *dev,
527						const u8 dpcd[DP_RECEIVER_CAP_SIZE],
528						const u8 port_cap[4]);
529int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]);
530void drm_dp_downstream_debug(struct seq_file *m,
531			     const u8 dpcd[DP_RECEIVER_CAP_SIZE],
532			     const u8 port_cap[4],
533			     const struct edid *edid,
534			     struct drm_dp_aux *aux);
535enum drm_mode_subconnector
536drm_dp_subconnector_type(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
537			 const u8 port_cap[4]);
538void drm_dp_set_subconnector_property(struct drm_connector *connector,
539				      enum drm_connector_status status,
540				      const u8 *dpcd,
541				      const u8 port_cap[4]);
542
543struct drm_dp_desc;
544bool drm_dp_read_sink_count_cap(struct drm_connector *connector,
545				const u8 dpcd[DP_RECEIVER_CAP_SIZE],
546				const struct drm_dp_desc *desc);
547int drm_dp_read_sink_count(struct drm_dp_aux *aux);
548
549int drm_dp_read_lttpr_common_caps(struct drm_dp_aux *aux,
550				  const u8 dpcd[DP_RECEIVER_CAP_SIZE],
551				  u8 caps[DP_LTTPR_COMMON_CAP_SIZE]);
552int drm_dp_read_lttpr_phy_caps(struct drm_dp_aux *aux,
553			       const u8 dpcd[DP_RECEIVER_CAP_SIZE],
554			       enum drm_dp_phy dp_phy,
555			       u8 caps[DP_LTTPR_PHY_CAP_SIZE]);
556int drm_dp_lttpr_count(const u8 cap[DP_LTTPR_COMMON_CAP_SIZE]);
557int drm_dp_lttpr_max_link_rate(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]);
558int drm_dp_lttpr_max_lane_count(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]);
559bool drm_dp_lttpr_voltage_swing_level_3_supported(const u8 caps[DP_LTTPR_PHY_CAP_SIZE]);
560bool drm_dp_lttpr_pre_emphasis_level_3_supported(const u8 caps[DP_LTTPR_PHY_CAP_SIZE]);
561
562void drm_dp_remote_aux_init(struct drm_dp_aux *aux);
563void drm_dp_aux_init(struct drm_dp_aux *aux);
564int drm_dp_aux_register(struct drm_dp_aux *aux);
565void drm_dp_aux_unregister(struct drm_dp_aux *aux);
566
567int drm_dp_start_crc(struct drm_dp_aux *aux, struct drm_crtc *crtc);
568int drm_dp_stop_crc(struct drm_dp_aux *aux);
569
570struct drm_dp_dpcd_ident {
571	u8 oui[3];
572	u8 device_id[6];
573	u8 hw_rev;
574	u8 sw_major_rev;
575	u8 sw_minor_rev;
576} __packed;
577
578/**
579 * struct drm_dp_desc - DP branch/sink device descriptor
580 * @ident: DP device identification from DPCD 0x400 (sink) or 0x500 (branch).
581 * @quirks: Quirks; use drm_dp_has_quirk() to query for the quirks.
582 */
583struct drm_dp_desc {
584	struct drm_dp_dpcd_ident ident;
585	u32 quirks;
586};
587
588int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc,
589		     bool is_branch);
590
591/**
592 * enum drm_dp_quirk - Display Port sink/branch device specific quirks
593 *
594 * Display Port sink and branch devices in the wild have a variety of bugs, try
595 * to collect them here. The quirks are shared, but it's up to the drivers to
596 * implement workarounds for them.
597 */
598enum drm_dp_quirk {
599	/**
600	 * @DP_DPCD_QUIRK_CONSTANT_N:
601	 *
602	 * The device requires main link attributes Mvid and Nvid to be limited
603	 * to 16 bits. So will give a constant value (0x8000) for compatability.
604	 */
605	DP_DPCD_QUIRK_CONSTANT_N,
606	/**
607	 * @DP_DPCD_QUIRK_NO_PSR:
608	 *
609	 * The device does not support PSR even if reports that it supports or
610	 * driver still need to implement proper handling for such device.
611	 */
612	DP_DPCD_QUIRK_NO_PSR,
613	/**
614	 * @DP_DPCD_QUIRK_NO_SINK_COUNT:
615	 *
616	 * The device does not set SINK_COUNT to a non-zero value.
617	 * The driver should ignore SINK_COUNT during detection. Note that
618	 * drm_dp_read_sink_count_cap() automatically checks for this quirk.
619	 */
620	DP_DPCD_QUIRK_NO_SINK_COUNT,
621	/**
622	 * @DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD:
623	 *
624	 * The device supports MST DSC despite not supporting Virtual DPCD.
625	 * The DSC caps can be read from the physical aux instead.
626	 */
627	DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD,
628	/**
629	 * @DP_DPCD_QUIRK_CAN_DO_MAX_LINK_RATE_3_24_GBPS:
630	 *
631	 * The device supports a link rate of 3.24 Gbps (multiplier 0xc) despite
632	 * the DP_MAX_LINK_RATE register reporting a lower max multiplier.
633	 */
634	DP_DPCD_QUIRK_CAN_DO_MAX_LINK_RATE_3_24_GBPS,
635};
636
637/**
638 * drm_dp_has_quirk() - does the DP device have a specific quirk
639 * @desc: Device descriptor filled by drm_dp_read_desc()
640 * @quirk: Quirk to query for
641 *
642 * Return true if DP device identified by @desc has @quirk.
643 */
644static inline bool
645drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk)
646{
647	return desc->quirks & BIT(quirk);
648}
649
650/**
651 * struct drm_edp_backlight_info - Probed eDP backlight info struct
652 * @pwmgen_bit_count: The pwmgen bit count
653 * @pwm_freq_pre_divider: The PWM frequency pre-divider value being used for this backlight, if any
654 * @max: The maximum backlight level that may be set
655 * @lsb_reg_used: Do we also write values to the DP_EDP_BACKLIGHT_BRIGHTNESS_LSB register?
656 * @aux_enable: Does the panel support the AUX enable cap?
657 * @aux_set: Does the panel support setting the brightness through AUX?
658 *
659 * This structure contains various data about an eDP backlight, which can be populated by using
660 * drm_edp_backlight_init().
661 */
662struct drm_edp_backlight_info {
663	u8 pwmgen_bit_count;
664	u8 pwm_freq_pre_divider;
665	u16 max;
666
667	bool lsb_reg_used : 1;
668	bool aux_enable : 1;
669	bool aux_set : 1;
670};
671
672int
673drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl,
674		       u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE],
675		       u16 *current_level, u8 *current_mode);
676int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl,
677				u16 level);
678int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl,
679			     u16 level);
680int drm_edp_backlight_disable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl);
681
682#if IS_ENABLED(CONFIG_DRM_KMS_HELPER) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \
683	(IS_MODULE(CONFIG_DRM_KMS_HELPER) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE)))
684
685int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux);
686
687#else
688
689static inline int drm_panel_dp_aux_backlight(struct drm_panel *panel,
690					     struct drm_dp_aux *aux)
691{
692	return 0;
693}
694
695#endif
696
697#ifdef CONFIG_DRM_DP_CEC
698void drm_dp_cec_irq(struct drm_dp_aux *aux);
699void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
700				   struct drm_connector *connector);
701void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux);
702void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid);
703void drm_dp_cec_unset_edid(struct drm_dp_aux *aux);
704#else
705static inline void drm_dp_cec_irq(struct drm_dp_aux *aux)
706{
707}
708
709static inline void
710drm_dp_cec_register_connector(struct drm_dp_aux *aux,
711			      struct drm_connector *connector)
712{
713}
714
715static inline void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux)
716{
717}
718
719static inline void drm_dp_cec_set_edid(struct drm_dp_aux *aux,
720				       const struct edid *edid)
721{
722}
723
724static inline void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
725{
726}
727
728#endif
729
730/**
731 * struct drm_dp_phy_test_params - DP Phy Compliance parameters
732 * @link_rate: Requested Link rate from DPCD 0x219
733 * @num_lanes: Number of lanes requested by sing through DPCD 0x220
734 * @phy_pattern: DP Phy test pattern from DPCD 0x248
735 * @hbr2_reset: DP HBR2_COMPLIANCE_SCRAMBLER_RESET from DCPD 0x24A and 0x24B
736 * @custom80: DP Test_80BIT_CUSTOM_PATTERN from DPCDs 0x250 through 0x259
737 * @enhanced_frame_cap: flag for enhanced frame capability.
738 */
739struct drm_dp_phy_test_params {
740	int link_rate;
741	u8 num_lanes;
742	u8 phy_pattern;
743	u8 hbr2_reset[2];
744	u8 custom80[10];
745	bool enhanced_frame_cap;
746};
747
748int drm_dp_get_phy_test_pattern(struct drm_dp_aux *aux,
749				struct drm_dp_phy_test_params *data);
750int drm_dp_set_phy_test_pattern(struct drm_dp_aux *aux,
751				struct drm_dp_phy_test_params *data, u8 dp_rev);
752int drm_dp_get_pcon_max_frl_bw(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
753			       const u8 port_cap[4]);
754int drm_dp_pcon_frl_prepare(struct drm_dp_aux *aux, bool enable_frl_ready_hpd);
755bool drm_dp_pcon_is_frl_ready(struct drm_dp_aux *aux);
756int drm_dp_pcon_frl_configure_1(struct drm_dp_aux *aux, int max_frl_gbps,
757				u8 frl_mode);
758int drm_dp_pcon_frl_configure_2(struct drm_dp_aux *aux, int max_frl_mask,
759				u8 frl_type);
760int drm_dp_pcon_reset_frl_config(struct drm_dp_aux *aux);
761int drm_dp_pcon_frl_enable(struct drm_dp_aux *aux);
762
763bool drm_dp_pcon_hdmi_link_active(struct drm_dp_aux *aux);
764int drm_dp_pcon_hdmi_link_mode(struct drm_dp_aux *aux, u8 *frl_trained_mask);
765void drm_dp_pcon_hdmi_frl_link_error_count(struct drm_dp_aux *aux,
766					   struct drm_connector *connector);
767bool drm_dp_pcon_enc_is_dsc_1_2(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]);
768int drm_dp_pcon_dsc_max_slices(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]);
769int drm_dp_pcon_dsc_max_slice_width(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]);
770int drm_dp_pcon_dsc_bpp_incr(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE]);
771int drm_dp_pcon_pps_default(struct drm_dp_aux *aux);
772int drm_dp_pcon_pps_override_buf(struct drm_dp_aux *aux, u8 pps_buf[128]);
773int drm_dp_pcon_pps_override_param(struct drm_dp_aux *aux, u8 pps_param[6]);
774bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
775					       const u8 port_cap[4], u8 color_spc);
776int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc);
777
778#endif /* _DRM_DP_HELPER_H_ */
779