cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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analogix-anx6345.c (20347B)


      1/* SPDX-License-Identifier: GPL-2.0-only */
      2/*
      3 * Copyright(c) 2016, Analogix Semiconductor.
      4 * Copyright(c) 2017, Icenowy Zheng <icenowy@aosc.io>
      5 *
      6 * Based on anx7808 driver obtained from chromeos with copyright:
      7 * Copyright(c) 2013, Google Inc.
      8 */
      9#include <linux/delay.h>
     10#include <linux/err.h>
     11#include <linux/gpio/consumer.h>
     12#include <linux/i2c.h>
     13#include <linux/interrupt.h>
     14#include <linux/kernel.h>
     15#include <linux/module.h>
     16#include <linux/of_platform.h>
     17#include <linux/regmap.h>
     18#include <linux/regulator/consumer.h>
     19#include <linux/types.h>
     20
     21#include <drm/display/drm_dp_helper.h>
     22#include <drm/drm_atomic_helper.h>
     23#include <drm/drm_bridge.h>
     24#include <drm/drm_crtc.h>
     25#include <drm/drm_crtc_helper.h>
     26#include <drm/drm_edid.h>
     27#include <drm/drm_of.h>
     28#include <drm/drm_panel.h>
     29#include <drm/drm_print.h>
     30#include <drm/drm_probe_helper.h>
     31
     32#include "analogix-i2c-dptx.h"
     33#include "analogix-i2c-txcommon.h"
     34
     35#define POLL_DELAY		50000 /* us */
     36#define POLL_TIMEOUT		5000000 /* us */
     37
     38#define I2C_IDX_DPTX		0
     39#define I2C_IDX_TXCOM		1
     40
     41static const u8 anx6345_i2c_addresses[] = {
     42	[I2C_IDX_DPTX]	= 0x70,
     43	[I2C_IDX_TXCOM]	= 0x72,
     44};
     45#define I2C_NUM_ADDRESSES	ARRAY_SIZE(anx6345_i2c_addresses)
     46
     47struct anx6345 {
     48	struct drm_dp_aux aux;
     49	struct drm_bridge bridge;
     50	struct i2c_client *client;
     51	struct edid *edid;
     52	struct drm_connector connector;
     53	struct drm_panel *panel;
     54	struct regulator *dvdd12;
     55	struct regulator *dvdd25;
     56	struct gpio_desc *gpiod_reset;
     57	struct mutex lock;	/* protect EDID access */
     58
     59	/* I2C Slave addresses of ANX6345 are mapped as DPTX and SYS */
     60	struct i2c_client *i2c_clients[I2C_NUM_ADDRESSES];
     61	struct regmap *map[I2C_NUM_ADDRESSES];
     62
     63	u16 chipid;
     64	u8 dpcd[DP_RECEIVER_CAP_SIZE];
     65
     66	bool powered;
     67};
     68
     69static inline struct anx6345 *connector_to_anx6345(struct drm_connector *c)
     70{
     71	return container_of(c, struct anx6345, connector);
     72}
     73
     74static inline struct anx6345 *bridge_to_anx6345(struct drm_bridge *bridge)
     75{
     76	return container_of(bridge, struct anx6345, bridge);
     77}
     78
     79static int anx6345_set_bits(struct regmap *map, u8 reg, u8 mask)
     80{
     81	return regmap_update_bits(map, reg, mask, mask);
     82}
     83
     84static int anx6345_clear_bits(struct regmap *map, u8 reg, u8 mask)
     85{
     86	return regmap_update_bits(map, reg, mask, 0);
     87}
     88
     89static ssize_t anx6345_aux_transfer(struct drm_dp_aux *aux,
     90				    struct drm_dp_aux_msg *msg)
     91{
     92	struct anx6345 *anx6345 = container_of(aux, struct anx6345, aux);
     93
     94	return anx_dp_aux_transfer(anx6345->map[I2C_IDX_DPTX], msg);
     95}
     96
     97static int anx6345_dp_link_training(struct anx6345 *anx6345)
     98{
     99	unsigned int value;
    100	u8 dp_bw, dpcd[2];
    101	int err;
    102
    103	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
    104				 SP_POWERDOWN_CTRL_REG,
    105				 SP_TOTAL_PD);
    106	if (err)
    107		return err;
    108
    109	err = drm_dp_dpcd_readb(&anx6345->aux, DP_MAX_LINK_RATE, &dp_bw);
    110	if (err < 0)
    111		return err;
    112
    113	switch (dp_bw) {
    114	case DP_LINK_BW_1_62:
    115	case DP_LINK_BW_2_7:
    116		break;
    117
    118	default:
    119		DRM_DEBUG_KMS("DP bandwidth (%#02x) not supported\n", dp_bw);
    120		return -EINVAL;
    121	}
    122
    123	err = anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL1_REG,
    124			       SP_VIDEO_MUTE);
    125	if (err)
    126		return err;
    127
    128	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
    129				 SP_VID_CTRL1_REG, SP_VIDEO_EN);
    130	if (err)
    131		return err;
    132
    133	/* Get DPCD info */
    134	err = drm_dp_dpcd_read(&anx6345->aux, DP_DPCD_REV,
    135			       &anx6345->dpcd, DP_RECEIVER_CAP_SIZE);
    136	if (err < 0) {
    137		DRM_ERROR("Failed to read DPCD: %d\n", err);
    138		return err;
    139	}
    140
    141	/* Clear channel x SERDES power down */
    142	err = anx6345_clear_bits(anx6345->map[I2C_IDX_DPTX],
    143				 SP_DP_ANALOG_POWER_DOWN_REG, SP_CH0_PD);
    144	if (err)
    145		return err;
    146
    147	/*
    148	 * Power up the sink (DP_SET_POWER register is only available on DPCD
    149	 * v1.1 and later).
    150	 */
    151	if (anx6345->dpcd[DP_DPCD_REV] >= 0x11) {
    152		err = drm_dp_dpcd_readb(&anx6345->aux, DP_SET_POWER, &dpcd[0]);
    153		if (err < 0) {
    154			DRM_ERROR("Failed to read DP_SET_POWER register: %d\n",
    155				  err);
    156			return err;
    157		}
    158
    159		dpcd[0] &= ~DP_SET_POWER_MASK;
    160		dpcd[0] |= DP_SET_POWER_D0;
    161
    162		err = drm_dp_dpcd_writeb(&anx6345->aux, DP_SET_POWER, dpcd[0]);
    163		if (err < 0) {
    164			DRM_ERROR("Failed to power up DisplayPort link: %d\n",
    165				  err);
    166			return err;
    167		}
    168
    169		/*
    170		 * According to the DP 1.1 specification, a "Sink Device must
    171		 * exit the power saving state within 1 ms" (Section 2.5.3.1,
    172		 * Table 5-52, "Sink Control Field" (register 0x600).
    173		 */
    174		usleep_range(1000, 2000);
    175	}
    176
    177	/* Possibly enable downspread on the sink */
    178	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    179			   SP_DP_DOWNSPREAD_CTRL1_REG, 0);
    180	if (err)
    181		return err;
    182
    183	if (anx6345->dpcd[DP_MAX_DOWNSPREAD] & DP_MAX_DOWNSPREAD_0_5) {
    184		DRM_DEBUG("Enable downspread on the sink\n");
    185		/* 4000PPM */
    186		err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    187				   SP_DP_DOWNSPREAD_CTRL1_REG, 8);
    188		if (err)
    189			return err;
    190
    191		err = drm_dp_dpcd_writeb(&anx6345->aux, DP_DOWNSPREAD_CTRL,
    192					 DP_SPREAD_AMP_0_5);
    193		if (err < 0)
    194			return err;
    195	} else {
    196		err = drm_dp_dpcd_writeb(&anx6345->aux, DP_DOWNSPREAD_CTRL, 0);
    197		if (err < 0)
    198			return err;
    199	}
    200
    201	/* Set the lane count and the link rate on the sink */
    202	if (drm_dp_enhanced_frame_cap(anx6345->dpcd))
    203		err = anx6345_set_bits(anx6345->map[I2C_IDX_DPTX],
    204				       SP_DP_SYSTEM_CTRL_BASE + 4,
    205				       SP_ENHANCED_MODE);
    206	else
    207		err = anx6345_clear_bits(anx6345->map[I2C_IDX_DPTX],
    208					 SP_DP_SYSTEM_CTRL_BASE + 4,
    209					 SP_ENHANCED_MODE);
    210	if (err)
    211		return err;
    212
    213	dpcd[0] = dp_bw;
    214	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    215			   SP_DP_MAIN_LINK_BW_SET_REG, dpcd[0]);
    216	if (err)
    217		return err;
    218
    219	dpcd[1] = drm_dp_max_lane_count(anx6345->dpcd);
    220
    221	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    222			   SP_DP_LANE_COUNT_SET_REG, dpcd[1]);
    223	if (err)
    224		return err;
    225
    226	if (drm_dp_enhanced_frame_cap(anx6345->dpcd))
    227		dpcd[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
    228
    229	err = drm_dp_dpcd_write(&anx6345->aux, DP_LINK_BW_SET, dpcd,
    230				sizeof(dpcd));
    231
    232	if (err < 0) {
    233		DRM_ERROR("Failed to configure link: %d\n", err);
    234		return err;
    235	}
    236
    237	/* Start training on the source */
    238	err = regmap_write(anx6345->map[I2C_IDX_DPTX], SP_DP_LT_CTRL_REG,
    239			   SP_LT_EN);
    240	if (err)
    241		return err;
    242
    243	return regmap_read_poll_timeout(anx6345->map[I2C_IDX_DPTX],
    244				       SP_DP_LT_CTRL_REG,
    245				       value, !(value & SP_DP_LT_INPROGRESS),
    246				       POLL_DELAY, POLL_TIMEOUT);
    247}
    248
    249static int anx6345_tx_initialization(struct anx6345 *anx6345)
    250{
    251	int err, i;
    252
    253	/* FIXME: colordepth is hardcoded for now */
    254	err = regmap_write(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL2_REG,
    255			   SP_IN_BPC_6BIT << SP_IN_BPC_SHIFT);
    256	if (err)
    257		return err;
    258
    259	err = regmap_write(anx6345->map[I2C_IDX_DPTX], SP_DP_PLL_CTRL_REG, 0);
    260	if (err)
    261		return err;
    262
    263	err = regmap_write(anx6345->map[I2C_IDX_TXCOM],
    264			   SP_ANALOG_DEBUG1_REG, 0);
    265	if (err)
    266		return err;
    267
    268	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    269			   SP_DP_LINK_DEBUG_CTRL_REG,
    270			   SP_NEW_PRBS7 | SP_M_VID_DEBUG);
    271	if (err)
    272		return err;
    273
    274	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    275			   SP_DP_ANALOG_POWER_DOWN_REG, 0);
    276	if (err)
    277		return err;
    278
    279	/* Force HPD */
    280	err = anx6345_set_bits(anx6345->map[I2C_IDX_DPTX],
    281			       SP_DP_SYSTEM_CTRL_BASE + 3,
    282			       SP_HPD_FORCE | SP_HPD_CTRL);
    283	if (err)
    284		return err;
    285
    286	for (i = 0; i < 4; i++) {
    287		/* 4 lanes */
    288		err = regmap_write(anx6345->map[I2C_IDX_DPTX],
    289				   SP_DP_LANE0_LT_CTRL_REG + i, 0);
    290		if (err)
    291			return err;
    292	}
    293
    294	/* Reset AUX */
    295	err = anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM],
    296			       SP_RESET_CTRL2_REG, SP_AUX_RST);
    297	if (err)
    298		return err;
    299
    300	return anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
    301				 SP_RESET_CTRL2_REG, SP_AUX_RST);
    302}
    303
    304static void anx6345_poweron(struct anx6345 *anx6345)
    305{
    306	int err;
    307
    308	/* Ensure reset is asserted before starting power on sequence */
    309	gpiod_set_value_cansleep(anx6345->gpiod_reset, 1);
    310	usleep_range(1000, 2000);
    311
    312	err = regulator_enable(anx6345->dvdd12);
    313	if (err) {
    314		DRM_ERROR("Failed to enable dvdd12 regulator: %d\n",
    315			  err);
    316		return;
    317	}
    318
    319	/* T1 - delay between VDD12 and VDD25 should be 0-2ms */
    320	usleep_range(1000, 2000);
    321
    322	err = regulator_enable(anx6345->dvdd25);
    323	if (err) {
    324		DRM_ERROR("Failed to enable dvdd25 regulator: %d\n",
    325			  err);
    326		return;
    327	}
    328
    329	/* T2 - delay between RESETN and all power rail stable,
    330	 * should be 2-5ms
    331	 */
    332	usleep_range(2000, 5000);
    333
    334	gpiod_set_value_cansleep(anx6345->gpiod_reset, 0);
    335
    336	/* Power on registers module */
    337	anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_POWERDOWN_CTRL_REG,
    338			 SP_HDCP_PD | SP_AUDIO_PD | SP_VIDEO_PD | SP_LINK_PD);
    339	anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM], SP_POWERDOWN_CTRL_REG,
    340			   SP_REGISTER_PD | SP_TOTAL_PD);
    341
    342	if (anx6345->panel)
    343		drm_panel_prepare(anx6345->panel);
    344
    345	anx6345->powered = true;
    346}
    347
    348static void anx6345_poweroff(struct anx6345 *anx6345)
    349{
    350	int err;
    351
    352	gpiod_set_value_cansleep(anx6345->gpiod_reset, 1);
    353	usleep_range(1000, 2000);
    354
    355	if (anx6345->panel)
    356		drm_panel_unprepare(anx6345->panel);
    357
    358	err = regulator_disable(anx6345->dvdd25);
    359	if (err) {
    360		DRM_ERROR("Failed to disable dvdd25 regulator: %d\n",
    361			  err);
    362		return;
    363	}
    364
    365	usleep_range(5000, 10000);
    366
    367	err = regulator_disable(anx6345->dvdd12);
    368	if (err) {
    369		DRM_ERROR("Failed to disable dvdd12 regulator: %d\n",
    370			  err);
    371		return;
    372	}
    373
    374	usleep_range(1000, 2000);
    375
    376	anx6345->powered = false;
    377}
    378
    379static int anx6345_start(struct anx6345 *anx6345)
    380{
    381	int err;
    382
    383	if (!anx6345->powered)
    384		anx6345_poweron(anx6345);
    385
    386	/* Power on needed modules */
    387	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
    388				SP_POWERDOWN_CTRL_REG,
    389				SP_VIDEO_PD | SP_LINK_PD);
    390
    391	err = anx6345_tx_initialization(anx6345);
    392	if (err) {
    393		DRM_ERROR("Failed eDP transmitter initialization: %d\n", err);
    394		anx6345_poweroff(anx6345);
    395		return err;
    396	}
    397
    398	err = anx6345_dp_link_training(anx6345);
    399	if (err) {
    400		DRM_ERROR("Failed link training: %d\n", err);
    401		anx6345_poweroff(anx6345);
    402		return err;
    403	}
    404
    405	/*
    406	 * This delay seems to help keep the hardware in a good state. Without
    407	 * it, there are times where it fails silently.
    408	 */
    409	usleep_range(10000, 15000);
    410
    411	return 0;
    412}
    413
    414static int anx6345_config_dp_output(struct anx6345 *anx6345)
    415{
    416	int err;
    417
    418	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL1_REG,
    419				 SP_VIDEO_MUTE);
    420	if (err)
    421		return err;
    422
    423	/* Enable DP output */
    424	err = anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL1_REG,
    425			       SP_VIDEO_EN);
    426	if (err)
    427		return err;
    428
    429	/* Force stream valid */
    430	return anx6345_set_bits(anx6345->map[I2C_IDX_DPTX],
    431			       SP_DP_SYSTEM_CTRL_BASE + 3,
    432			       SP_STRM_FORCE | SP_STRM_CTRL);
    433}
    434
    435static int anx6345_get_downstream_info(struct anx6345 *anx6345)
    436{
    437	u8 value;
    438	int err;
    439
    440	err = drm_dp_dpcd_readb(&anx6345->aux, DP_SINK_COUNT, &value);
    441	if (err < 0) {
    442		DRM_ERROR("Get sink count failed %d\n", err);
    443		return err;
    444	}
    445
    446	if (!DP_GET_SINK_COUNT(value)) {
    447		DRM_ERROR("Downstream disconnected\n");
    448		return -EIO;
    449	}
    450
    451	return 0;
    452}
    453
    454static int anx6345_get_modes(struct drm_connector *connector)
    455{
    456	struct anx6345 *anx6345 = connector_to_anx6345(connector);
    457	int err, num_modes = 0;
    458	bool power_off = false;
    459
    460	mutex_lock(&anx6345->lock);
    461
    462	if (!anx6345->edid) {
    463		if (!anx6345->powered) {
    464			anx6345_poweron(anx6345);
    465			power_off = true;
    466		}
    467
    468		err = anx6345_get_downstream_info(anx6345);
    469		if (err) {
    470			DRM_ERROR("Failed to get downstream info: %d\n", err);
    471			goto unlock;
    472		}
    473
    474		anx6345->edid = drm_get_edid(connector, &anx6345->aux.ddc);
    475		if (!anx6345->edid)
    476			DRM_ERROR("Failed to read EDID from panel\n");
    477
    478		err = drm_connector_update_edid_property(connector,
    479							 anx6345->edid);
    480		if (err) {
    481			DRM_ERROR("Failed to update EDID property: %d\n", err);
    482			goto unlock;
    483		}
    484	}
    485
    486	num_modes += drm_add_edid_modes(connector, anx6345->edid);
    487
    488	/* Driver currently supports only 6bpc */
    489	connector->display_info.bpc = 6;
    490
    491unlock:
    492	if (power_off)
    493		anx6345_poweroff(anx6345);
    494
    495	mutex_unlock(&anx6345->lock);
    496
    497	if (!num_modes && anx6345->panel)
    498		num_modes += drm_panel_get_modes(anx6345->panel, connector);
    499
    500	return num_modes;
    501}
    502
    503static const struct drm_connector_helper_funcs anx6345_connector_helper_funcs = {
    504	.get_modes = anx6345_get_modes,
    505};
    506
    507static void
    508anx6345_connector_destroy(struct drm_connector *connector)
    509{
    510	drm_connector_cleanup(connector);
    511}
    512
    513static const struct drm_connector_funcs anx6345_connector_funcs = {
    514	.fill_modes = drm_helper_probe_single_connector_modes,
    515	.destroy = anx6345_connector_destroy,
    516	.reset = drm_atomic_helper_connector_reset,
    517	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
    518	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
    519};
    520
    521static int anx6345_bridge_attach(struct drm_bridge *bridge,
    522				 enum drm_bridge_attach_flags flags)
    523{
    524	struct anx6345 *anx6345 = bridge_to_anx6345(bridge);
    525	int err;
    526
    527	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
    528		DRM_ERROR("Fix bridge driver to make connector optional!");
    529		return -EINVAL;
    530	}
    531
    532	if (!bridge->encoder) {
    533		DRM_ERROR("Parent encoder object not found");
    534		return -ENODEV;
    535	}
    536
    537	/* Register aux channel */
    538	anx6345->aux.name = "DP-AUX";
    539	anx6345->aux.dev = &anx6345->client->dev;
    540	anx6345->aux.drm_dev = bridge->dev;
    541	anx6345->aux.transfer = anx6345_aux_transfer;
    542
    543	err = drm_dp_aux_register(&anx6345->aux);
    544	if (err < 0) {
    545		DRM_ERROR("Failed to register aux channel: %d\n", err);
    546		return err;
    547	}
    548
    549	err = drm_connector_init(bridge->dev, &anx6345->connector,
    550				 &anx6345_connector_funcs,
    551				 DRM_MODE_CONNECTOR_eDP);
    552	if (err) {
    553		DRM_ERROR("Failed to initialize connector: %d\n", err);
    554		goto aux_unregister;
    555	}
    556
    557	drm_connector_helper_add(&anx6345->connector,
    558				 &anx6345_connector_helper_funcs);
    559
    560	anx6345->connector.polled = DRM_CONNECTOR_POLL_HPD;
    561
    562	err = drm_connector_attach_encoder(&anx6345->connector,
    563					   bridge->encoder);
    564	if (err) {
    565		DRM_ERROR("Failed to link up connector to encoder: %d\n", err);
    566		goto connector_cleanup;
    567	}
    568
    569	err = drm_connector_register(&anx6345->connector);
    570	if (err) {
    571		DRM_ERROR("Failed to register connector: %d\n", err);
    572		goto connector_cleanup;
    573	}
    574
    575	return 0;
    576connector_cleanup:
    577	drm_connector_cleanup(&anx6345->connector);
    578aux_unregister:
    579	drm_dp_aux_unregister(&anx6345->aux);
    580	return err;
    581}
    582
    583static void anx6345_bridge_detach(struct drm_bridge *bridge)
    584{
    585	drm_dp_aux_unregister(&bridge_to_anx6345(bridge)->aux);
    586}
    587
    588static enum drm_mode_status
    589anx6345_bridge_mode_valid(struct drm_bridge *bridge,
    590			  const struct drm_display_info *info,
    591			  const struct drm_display_mode *mode)
    592{
    593	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
    594		return MODE_NO_INTERLACE;
    595
    596	/* Max 1200p at 5.4 Ghz, one lane */
    597	if (mode->clock > 154000)
    598		return MODE_CLOCK_HIGH;
    599
    600	return MODE_OK;
    601}
    602
    603static void anx6345_bridge_disable(struct drm_bridge *bridge)
    604{
    605	struct anx6345 *anx6345 = bridge_to_anx6345(bridge);
    606
    607	/* Power off all modules except configuration registers access */
    608	anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_POWERDOWN_CTRL_REG,
    609			 SP_HDCP_PD | SP_AUDIO_PD | SP_VIDEO_PD | SP_LINK_PD);
    610	if (anx6345->panel)
    611		drm_panel_disable(anx6345->panel);
    612
    613	if (anx6345->powered)
    614		anx6345_poweroff(anx6345);
    615}
    616
    617static void anx6345_bridge_enable(struct drm_bridge *bridge)
    618{
    619	struct anx6345 *anx6345 = bridge_to_anx6345(bridge);
    620	int err;
    621
    622	if (anx6345->panel)
    623		drm_panel_enable(anx6345->panel);
    624
    625	err = anx6345_start(anx6345);
    626	if (err) {
    627		DRM_ERROR("Failed to initialize: %d\n", err);
    628		return;
    629	}
    630
    631	err = anx6345_config_dp_output(anx6345);
    632	if (err)
    633		DRM_ERROR("Failed to enable DP output: %d\n", err);
    634}
    635
    636static const struct drm_bridge_funcs anx6345_bridge_funcs = {
    637	.attach = anx6345_bridge_attach,
    638	.detach = anx6345_bridge_detach,
    639	.mode_valid = anx6345_bridge_mode_valid,
    640	.disable = anx6345_bridge_disable,
    641	.enable = anx6345_bridge_enable,
    642};
    643
    644static void unregister_i2c_dummy_clients(struct anx6345 *anx6345)
    645{
    646	unsigned int i;
    647
    648	for (i = 1; i < ARRAY_SIZE(anx6345->i2c_clients); i++)
    649		if (anx6345->i2c_clients[i] &&
    650		    anx6345->i2c_clients[i]->addr != anx6345->client->addr)
    651			i2c_unregister_device(anx6345->i2c_clients[i]);
    652}
    653
    654static const struct regmap_config anx6345_regmap_config = {
    655	.reg_bits = 8,
    656	.val_bits = 8,
    657	.max_register = 0xff,
    658	.cache_type = REGCACHE_NONE,
    659};
    660
    661static const u16 anx6345_chipid_list[] = {
    662	0x6345,
    663};
    664
    665static bool anx6345_get_chip_id(struct anx6345 *anx6345)
    666{
    667	unsigned int i, idl, idh, version;
    668
    669	if (regmap_read(anx6345->map[I2C_IDX_TXCOM], SP_DEVICE_IDL_REG, &idl))
    670		return false;
    671
    672	if (regmap_read(anx6345->map[I2C_IDX_TXCOM], SP_DEVICE_IDH_REG, &idh))
    673		return false;
    674
    675	anx6345->chipid = (u8)idl | ((u8)idh << 8);
    676
    677	if (regmap_read(anx6345->map[I2C_IDX_TXCOM], SP_DEVICE_VERSION_REG,
    678			&version))
    679		return false;
    680
    681	for (i = 0; i < ARRAY_SIZE(anx6345_chipid_list); i++) {
    682		if (anx6345->chipid == anx6345_chipid_list[i]) {
    683			DRM_INFO("Found ANX%x (ver. %d) eDP Transmitter\n",
    684				 anx6345->chipid, version);
    685			return true;
    686		}
    687	}
    688
    689	DRM_ERROR("ANX%x (ver. %d) not supported by this driver\n",
    690		  anx6345->chipid, version);
    691
    692	return false;
    693}
    694
    695static int anx6345_i2c_probe(struct i2c_client *client,
    696			     const struct i2c_device_id *id)
    697{
    698	struct anx6345 *anx6345;
    699	struct device *dev;
    700	int i, err;
    701
    702	anx6345 = devm_kzalloc(&client->dev, sizeof(*anx6345), GFP_KERNEL);
    703	if (!anx6345)
    704		return -ENOMEM;
    705
    706	mutex_init(&anx6345->lock);
    707
    708	anx6345->bridge.of_node = client->dev.of_node;
    709
    710	anx6345->client = client;
    711	i2c_set_clientdata(client, anx6345);
    712
    713	dev = &anx6345->client->dev;
    714
    715	err = drm_of_find_panel_or_bridge(client->dev.of_node, 1, 0,
    716					  &anx6345->panel, NULL);
    717	if (err == -EPROBE_DEFER)
    718		return err;
    719
    720	if (err)
    721		DRM_DEBUG("No panel found\n");
    722
    723	/* 1.2V digital core power regulator  */
    724	anx6345->dvdd12 = devm_regulator_get(dev, "dvdd12");
    725	if (IS_ERR(anx6345->dvdd12)) {
    726		if (PTR_ERR(anx6345->dvdd12) != -EPROBE_DEFER)
    727			DRM_ERROR("Failed to get dvdd12 supply (%ld)\n",
    728				  PTR_ERR(anx6345->dvdd12));
    729		return PTR_ERR(anx6345->dvdd12);
    730	}
    731
    732	/* 2.5V digital core power regulator  */
    733	anx6345->dvdd25 = devm_regulator_get(dev, "dvdd25");
    734	if (IS_ERR(anx6345->dvdd25)) {
    735		if (PTR_ERR(anx6345->dvdd25) != -EPROBE_DEFER)
    736			DRM_ERROR("Failed to get dvdd25 supply (%ld)\n",
    737				  PTR_ERR(anx6345->dvdd25));
    738		return PTR_ERR(anx6345->dvdd25);
    739	}
    740
    741	/* GPIO for chip reset */
    742	anx6345->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
    743	if (IS_ERR(anx6345->gpiod_reset)) {
    744		DRM_ERROR("Reset gpio not found\n");
    745		return PTR_ERR(anx6345->gpiod_reset);
    746	}
    747
    748	/* Map slave addresses of ANX6345 */
    749	for (i = 0; i < I2C_NUM_ADDRESSES; i++) {
    750		if (anx6345_i2c_addresses[i] >> 1 != client->addr)
    751			anx6345->i2c_clients[i] = i2c_new_dummy_device(client->adapter,
    752						anx6345_i2c_addresses[i] >> 1);
    753		else
    754			anx6345->i2c_clients[i] = client;
    755
    756		if (IS_ERR(anx6345->i2c_clients[i])) {
    757			err = PTR_ERR(anx6345->i2c_clients[i]);
    758			DRM_ERROR("Failed to reserve I2C bus %02x\n",
    759				  anx6345_i2c_addresses[i]);
    760			goto err_unregister_i2c;
    761		}
    762
    763		anx6345->map[i] = devm_regmap_init_i2c(anx6345->i2c_clients[i],
    764						       &anx6345_regmap_config);
    765		if (IS_ERR(anx6345->map[i])) {
    766			err = PTR_ERR(anx6345->map[i]);
    767			DRM_ERROR("Failed regmap initialization %02x\n",
    768				  anx6345_i2c_addresses[i]);
    769			goto err_unregister_i2c;
    770		}
    771	}
    772
    773	/* Look for supported chip ID */
    774	anx6345_poweron(anx6345);
    775	if (anx6345_get_chip_id(anx6345)) {
    776		anx6345->bridge.funcs = &anx6345_bridge_funcs;
    777		drm_bridge_add(&anx6345->bridge);
    778
    779		return 0;
    780	} else {
    781		anx6345_poweroff(anx6345);
    782		err = -ENODEV;
    783	}
    784
    785err_unregister_i2c:
    786	unregister_i2c_dummy_clients(anx6345);
    787	return err;
    788}
    789
    790static int anx6345_i2c_remove(struct i2c_client *client)
    791{
    792	struct anx6345 *anx6345 = i2c_get_clientdata(client);
    793
    794	drm_bridge_remove(&anx6345->bridge);
    795
    796	unregister_i2c_dummy_clients(anx6345);
    797
    798	kfree(anx6345->edid);
    799
    800	mutex_destroy(&anx6345->lock);
    801
    802	return 0;
    803}
    804
    805static const struct i2c_device_id anx6345_id[] = {
    806	{ "anx6345", 0 },
    807	{ /* sentinel */ }
    808};
    809MODULE_DEVICE_TABLE(i2c, anx6345_id);
    810
    811static const struct of_device_id anx6345_match_table[] = {
    812	{ .compatible = "analogix,anx6345", },
    813	{ /* sentinel */ },
    814};
    815MODULE_DEVICE_TABLE(of, anx6345_match_table);
    816
    817static struct i2c_driver anx6345_driver = {
    818	.driver = {
    819		   .name = "anx6345",
    820		   .of_match_table = of_match_ptr(anx6345_match_table),
    821		  },
    822	.probe = anx6345_i2c_probe,
    823	.remove = anx6345_i2c_remove,
    824	.id_table = anx6345_id,
    825};
    826module_i2c_driver(anx6345_driver);
    827
    828MODULE_DESCRIPTION("ANX6345 eDP Transmitter driver");
    829MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
    830MODULE_LICENSE("GPL v2");