summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/bridge/sn65dsi83/sn65dsi83_brg.c
blob: f4a7713635d6dd511b6800842a03d7cc7a322a62 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
/*
 * Copyright (C) 2018 CopuLab Ltd.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/i2c.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_graph.h>
#include <linux/slab.h>

#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_connector.h>
#include <video/mipi_display.h>
#include <video/of_videomode.h>
#include <video/videomode.h>

#include "sn65dsi83_brg.h"

/* Register addresses */

#define SN65DSI83_SOFT_RESET         0x09
#define SN65DSI83_CORE_PLL           0x0A
    #define LVDS_CLK_RANGE_SHIFT    1
    #define HS_CLK_SRC_SHIFT        0

#define SN65DSI83_PLL_DIV            0x0B
    #define DSI_CLK_DIV_SHIFT       3

#define SN65DSI83_PLL_EN             0x0D
#define SN65DSI83_DSI_CFG            0x10
    #define CHA_DSI_LANES_SHIFT    3

#define SN65DSI83_DSI_EQ              0x11
#define SN65DSI83_CHA_DSI_CLK_RNG     0x12
#define SN65DSI83_CHB_DSI_CLK_RNG     0x13
#define SN65DSI83_LVDS_MODE           0x18
    #define DE_NEG_POLARITY_SHIFT 7
    #define HS_NEG_POLARITY_SHIFT 6
    #define VS_NEG_POLARITY_SHIFT 5
    #define LVDS_LINK_CFG_SHIFT   4
    #define CHA_24BPP_MODE_SHIFT  3
    #define CHA_24BPP_FMT1_SHIFT  1

#define SN65DSI83_LVDS_SIGN           0x19
#define SN65DSI83_LVDS_TERM           0x1A
#define SN65DSI83_LVDS_CM_ADJ         0x1B
#define SN65DSI83_CHA_LINE_LEN_LO     0x20
#define SN65DSI83_CHA_LINE_LEN_HI     0x21
#define SN65DSI83_CHB_LINE_LEN_LO     0x22
#define SN65DSI83_CHB_LINE_LEN_HI     0x23
#define SN65DSI83_CHA_VERT_LINES_LO   0x24
#define SN65DSI83_CHA_VERT_LINES_HI   0x25
#define SN65DSI83_CHB_VERT_LINES_LO   0x26
#define SN65DSI83_CHB_VERT_LINES_HI   0x27
#define SN65DSI83_CHA_SYNC_DELAY_LO   0x28
#define SN65DSI83_CHA_SYNC_DELAY_HI   0x29
#define SN65DSI83_CHB_SYNC_DELAY_LO   0x2A
#define SN65DSI83_CHB_SYNC_DELAY_HI   0x2B
#define SN65DSI83_CHA_HSYNC_WIDTH_LO  0x2C
#define SN65DSI83_CHA_HSYNC_WIDTH_HI  0x2D
#define SN65DSI83_CHB_HSYNC_WIDTH_LO  0x2E
#define SN65DSI83_CHB_HSYNC_WIDTH_HI  0x2F
#define SN65DSI83_CHA_VSYNC_WIDTH_LO  0x30
#define SN65DSI83_CHA_VSYNC_WIDTH_HI  0x31
#define SN65DSI83_CHB_VSYNC_WIDTH_LO  0x32
#define SN65DSI83_CHB_VSYNC_WIDTH_HI  0x33
#define SN65DSI83_CHA_HORZ_BACKPORCH  0x34
#define SN65DSI83_CHB_HORZ_BACKPORCH  0x35
#define SN65DSI83_CHA_VERT_BACKPORCH  0x36
#define SN65DSI83_CHB_VERT_BACKPORCH  0x37
#define SN65DSI83_CHA_HORZ_FRONTPORCH 0x38
#define SN65DSI83_CHB_HORZ_FRONTPORCH 0x39
#define SN65DSI83_CHA_VERT_FRONTPORCH 0x3A
#define SN65DSI83_CHB_VERT_FRONTPORCH 0x3B
#define SN65DSI83_CHA_ERR             0xE5
#define SN65DSI83_TEST_PATTERN        0x3C
#define SN65DSI83_REG_3D              0x3D
#define SN65DSI83_REG_3E              0x3E

static int sn65dsi83_brg_power_on(struct sn65dsi83_brg *brg)
{
    dev_info(&brg->client->dev,"%s\n",__func__);
    gpiod_set_value_cansleep(brg->gpio_enable, 1);
    /* Wait for 1ms for the internal voltage regulator to stabilize */
    msleep(1);

    return 0;
}

static void sn65dsi83_brg_power_off(struct sn65dsi83_brg *brg)
{
    dev_info(&brg->client->dev,"%s\n",__func__);
    gpiod_set_value_cansleep(brg->gpio_enable, 0);
    /*
     * The EN pin must be held low for at least 10 ms
     * before being asserted high
     */
    msleep(10);
}

static int sn65dsi83_write(struct i2c_client *client, u8 reg, u8 val)
{
    int ret;

    ret = i2c_smbus_write_byte_data(client, reg, val);

    if (ret)
        dev_err(&client->dev, "failed to write at 0x%02x", reg);

    dev_dbg(&client->dev, "%s: write reg 0x%02x data 0x%02x", __func__, reg, val);

    return ret;
}
#define SN65DSI83_WRITE(reg,val) sn65dsi83_write(client, (reg) , (val))

static int sn65dsi83_read(struct i2c_client *client, u8 reg)
{
    int ret;

    dev_info(&client->dev, "client 0x%p", client);
    ret = i2c_smbus_read_byte_data(client, reg);

    if (ret < 0) {
        dev_err(&client->dev, "failed reading at 0x%02x", reg);
        return ret;
    }

    dev_dbg(&client->dev, "%s: read reg 0x%02x data 0x%02x", __func__, reg, ret);

    return ret;
}
#define SN65DSI83_READ(reg) sn65dsi83_read(client, (reg))

static int sn65dsi83_brg_start_stream(struct sn65dsi83_brg *brg)
{
    int regval;
    struct i2c_client *client = I2C_CLIENT(brg);

    dev_info(&client->dev,"%s\n",__func__);
    /* Set the PLL_EN bit (CSR 0x0D.0) */
    SN65DSI83_WRITE(SN65DSI83_PLL_EN, 0x1);
    /* Wait for the PLL_LOCK bit to be set (CSR 0x0A.7) */
    msleep(200);

    /* Perform SW reset to apply changes */
    SN65DSI83_WRITE(SN65DSI83_SOFT_RESET, 0x01);

    /* Read CHA Error register */
    regval = SN65DSI83_READ(SN65DSI83_CHA_ERR);
    dev_info(&client->dev, "CHA (0x%02x) = 0x%02x",
         SN65DSI83_CHA_ERR, regval);

    return 0;
}

static void sn65dsi83_brg_stop_stream(struct sn65dsi83_brg *brg)
{
    struct i2c_client *client = I2C_CLIENT(brg);
    dev_info(&client->dev,"%s\n",__func__);
    /* Clear the PLL_EN bit (CSR 0x0D.0) */
    SN65DSI83_WRITE(SN65DSI83_PLL_EN, 0x00);
}

static int sn65dsi83_calk_clk_range(int min_regval, int max_regval,
                unsigned long min_clk, unsigned long inc,
                unsigned long target_clk)
{
    int regval = min_regval;
    unsigned long clk = min_clk;

    while (regval <= max_regval) {
        if ((clk <= target_clk) && (target_clk < (clk + inc)))
            return regval;

        regval++;
        clk += inc;
    }

    return -1;
}

#define ABS(X) ((X) < 0 ? (-1 * (X)) : (X))
static int sn65dsi83_calk_div(int min_regval, int max_regval, int min_div,
                int inc, unsigned long source_clk,
                unsigned long target_clk)
{
    int regval = min_regval;
    int div = min_div;
    unsigned long curr_delta;
    unsigned long prev_delta = ABS(DIV_ROUND_UP(source_clk, div) -
                    target_clk);

    while (regval <= max_regval) {
        curr_delta = ABS(DIV_ROUND_UP(source_clk, div) - target_clk);
        if (curr_delta > prev_delta)
            return --regval;

        regval++;
        div += inc;
    }

    return -1;
}

static int sn65dsi83_brg_configure(struct sn65dsi83_brg *brg)
{
    int regval = 0;
    struct i2c_client *client = I2C_CLIENT(brg);
    struct videomode *vm = VM(brg);

    u32 dsi_clk = (((PIXCLK * BPP(brg)) / DSI_LANES(brg)) >> 1);

    dev_info(&client->dev, "DSI clock [ %u ] Hz\n",dsi_clk);
    dev_info(&client->dev, "GeoMetry [ %d x %d ] Hz\n",HACTIVE,VACTIVE);

    /* Reset PLL_EN and SOFT_RESET registers */
    SN65DSI83_WRITE(SN65DSI83_SOFT_RESET,0x00);
    SN65DSI83_WRITE(SN65DSI83_PLL_EN,0x00);

    /* LVDS clock setup */
    if  ((25000000 <= PIXCLK) && (PIXCLK < 37500000))
        regval = 0;
    else
        regval = sn65dsi83_calk_clk_range(0x01, 0x05, 37500000, 25000000,
                    PIXCLK);

    if (regval < 0) {
        dev_err(&client->dev, "failed to configure LVDS clock");
        return -EINVAL;
    }

    regval = (regval << LVDS_CLK_RANGE_SHIFT);
    regval |= (1 << HS_CLK_SRC_SHIFT); /* Use DSI clock */
    SN65DSI83_WRITE(SN65DSI83_CORE_PLL,regval);

    /* DSI clock range */
    regval = sn65dsi83_calk_clk_range(0x08, 0x64, 40000000, 5000000, dsi_clk);
    if (regval < 0) {
        dev_err(&client->dev, "failed to configure DSI clock range\n");
        return -EINVAL;
    }
    SN65DSI83_WRITE(SN65DSI83_CHA_DSI_CLK_RNG,regval);

    /* DSI clock divider */
    regval = sn65dsi83_calk_div(0x0, 0x18, 1, 1, dsi_clk, PIXCLK);
    if (regval < 0) {
        dev_err(&client->dev, "failed to calculate DSI clock divider");
        return -EINVAL;
    }

    regval = regval << DSI_CLK_DIV_SHIFT;
    SN65DSI83_WRITE(SN65DSI83_PLL_DIV,regval);

    /* Configure DSI_LANES  */
    regval = SN65DSI83_READ(SN65DSI83_DSI_CFG);
    regval &= ~(3 << CHA_DSI_LANES_SHIFT);
    regval |= ((4 - DSI_LANES(brg)) << CHA_DSI_LANES_SHIFT);
    SN65DSI83_WRITE(SN65DSI83_DSI_CFG,regval);

    /* CHA_DSI_DATA_EQ - No Equalization */
    /* CHA_DSI_CLK_EQ  - No Equalization */
    SN65DSI83_WRITE(SN65DSI83_DSI_EQ,0x00);

    /* Video formats */
    regval = 0;
    if (FLAGS & DISPLAY_FLAGS_HSYNC_LOW)
        regval |= (1 << HS_NEG_POLARITY_SHIFT);

    if (FLAGS & DISPLAY_FLAGS_VSYNC_LOW)
        regval |= (1 << VS_NEG_POLARITY_SHIFT);

    if (FLAGS & DISPLAY_FLAGS_DE_LOW)
        regval |= (1 << DE_NEG_POLARITY_SHIFT);

    if (BPP(brg) == 24)
        regval |= (1 << CHA_24BPP_MODE_SHIFT);

    if (FORMAT(brg) == 1)
        regval |= (1 << CHA_24BPP_FMT1_SHIFT);

    regval |= (1 << LVDS_LINK_CFG_SHIFT);
    SN65DSI83_WRITE(SN65DSI83_LVDS_MODE,regval);

    /* Voltage and pins */
    SN65DSI83_WRITE(SN65DSI83_LVDS_SIGN,0x00);
    SN65DSI83_WRITE(SN65DSI83_LVDS_TERM,0x03);
    SN65DSI83_WRITE(SN65DSI83_LVDS_CM_ADJ,0x00);

    /* Configure sync delay to minimal allowed value */
    SN65DSI83_WRITE(SN65DSI83_CHA_SYNC_DELAY_LO,0x21);
    SN65DSI83_WRITE(SN65DSI83_CHA_SYNC_DELAY_HI,0x00);

    /* Geometry */
    SN65DSI83_WRITE(SN65DSI83_CHA_LINE_LEN_LO,LOW(HACTIVE));
    SN65DSI83_WRITE(SN65DSI83_CHA_LINE_LEN_HI,HIGH(HACTIVE));

    SN65DSI83_WRITE(SN65DSI83_CHA_VERT_LINES_LO,LOW(VACTIVE));
    SN65DSI83_WRITE(SN65DSI83_CHA_VERT_LINES_HI,HIGH(VACTIVE));

    SN65DSI83_WRITE(SN65DSI83_CHA_HSYNC_WIDTH_LO,LOW(HPW));
    SN65DSI83_WRITE(SN65DSI83_CHA_HSYNC_WIDTH_HI,HIGH(HPW));

    SN65DSI83_WRITE(SN65DSI83_CHA_VSYNC_WIDTH_LO,LOW(VPW));
    SN65DSI83_WRITE(SN65DSI83_CHA_VSYNC_WIDTH_HI,HIGH(VPW));

    SN65DSI83_WRITE(SN65DSI83_CHA_HORZ_BACKPORCH,LOW(HBP));
    SN65DSI83_WRITE(SN65DSI83_CHA_VERT_BACKPORCH,LOW(VBP));

    SN65DSI83_WRITE(SN65DSI83_CHA_HORZ_FRONTPORCH,LOW(HFP));
    SN65DSI83_WRITE(SN65DSI83_CHA_VERT_FRONTPORCH,LOW(VFP));

    SN65DSI83_WRITE(SN65DSI83_TEST_PATTERN,0x00);
    SN65DSI83_WRITE(SN65DSI83_REG_3D,0x00);
    SN65DSI83_WRITE(SN65DSI83_REG_3E,0x00);

    /* mute channel B */
    SN65DSI83_WRITE(SN65DSI83_CHB_DSI_CLK_RNG, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_LINE_LEN_LO, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_LINE_LEN_HI, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_VERT_LINES_LO, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_VERT_LINES_HI, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_SYNC_DELAY_LO, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_SYNC_DELAY_HI, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_HSYNC_WIDTH_LO, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_HSYNC_WIDTH_HI, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_VSYNC_WIDTH_LO, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_VSYNC_WIDTH_HI, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_HORZ_BACKPORCH, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_VERT_BACKPORCH, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_HORZ_FRONTPORCH, 0x00);
    SN65DSI83_WRITE(SN65DSI83_CHB_VERT_FRONTPORCH, 0x00);
    return 0;
}

static int sn65dsi83_brg_setup(struct sn65dsi83_brg *brg)
{
    struct i2c_client *client = I2C_CLIENT(brg);
    dev_info(&client->dev,"%s\n",__func__);
    sn65dsi83_brg_power_on(brg);
    return sn65dsi83_brg_configure(brg);
}

static int sn65dsi83_brg_reset(struct sn65dsi83_brg *brg)
{
    /* Soft Reset reg value at power on should be 0x00 */
    struct i2c_client *client = I2C_CLIENT(brg);
    int ret = SN65DSI83_READ(SN65DSI83_SOFT_RESET);
    dev_info(&client->dev,"%s\n",__func__);
    if (ret != 0x00) {
        dev_err(&client->dev,"Failed to reset the device");
        return -ENODEV;
    }
    return 0;
}

static struct sn65dsi83_brg_funcs brg_func = {
    .power_on = sn65dsi83_brg_power_on,
    .power_off = sn65dsi83_brg_power_off,
    .setup = sn65dsi83_brg_setup,
    .reset = sn65dsi83_brg_reset,
    .start_stream = sn65dsi83_brg_start_stream,
    .stop_stream = sn65dsi83_brg_stop_stream,
};

static struct sn65dsi83_brg brg = {
    .funcs = &brg_func,
};

struct sn65dsi83_brg *sn65dsi83_brg_get(void) {
    return &brg;
}