drm/linux-core/drm_edid.c

494 lines
13 KiB
C

/*
* Copyright (c) 2007 Intel Corporation
* Jesse Barnes <jesse.barnes@intel.com>
*
* DDC probing routines (drm_ddc_read & drm_do_probe_ddc_edid) originally from
* FB layer.
* Copyright (C) 2006 Dennis Munsie <dmunsie@cecropia.com>
*/
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include "drmP.h"
#include "drm_edid.h"
/* Valid EDID header has these bytes */
static u8 edid_header[] = { 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00 };
/**
* edid_valid - sanity check EDID data
* @edid: EDID data
*
* Sanity check the EDID block by looking at the header, the version number
* and the checksum. Return 0 if the EDID doesn't check out, or 1 if it's
* valid.
*/
static bool edid_valid(struct edid *edid)
{
int i;
u8 csum = 0;
u8 *raw_edid = (u8 *)edid;
if (memcmp(edid->header, edid_header, sizeof(edid_header)))
goto bad;
if (edid->version != 1)
goto bad;
if (edid->revision <= 0 || edid->revision > 3)
goto bad;
for (i = 0; i < EDID_LENGTH; i++)
csum += raw_edid[i];
if (csum)
goto bad;
return 1;
bad:
return 0;
}
/**
* drm_mode_std - convert standard mode info (width, height, refresh) into mode
* @t: standard timing params
*
* Take the standard timing params (in this case width, aspect, and refresh)
* and convert them into a real mode using CVT.
*
* Punts for now, but should eventually use the FB layer's CVT based mode
* generation code.
*/
struct drm_display_mode *drm_mode_std(struct drm_device *dev,
struct std_timing *t)
{
// struct fb_videomode mode;
// fb_find_mode_cvt(&mode, 0, 0);
/* JJJ: convert to drm_display_mode */
struct drm_display_mode *mode;
int hsize = t->hsize * 8 + 248, vsize;
mode = drm_mode_create(dev);
if (!mode)
return NULL;
if (t->aspect_ratio == 0)
vsize = (hsize * 10) / 16;
else if (t->aspect_ratio == 1)
vsize = (hsize * 3) / 4;
else if (t->aspect_ratio == 2)
vsize = (hsize * 4) / 5;
else
vsize = (hsize * 9) / 16;
drm_mode_set_name(mode);
return mode;
}
/**
* drm_mode_detailed - create a new mode from an EDID detailed timing section
* @timing: EDID detailed timing info
* @preferred: is this a preferred mode?
*
* An EDID detailed timing block contains enough info for us to create and
* return a new struct drm_display_mode. The @preferred flag will be set
* if this is the display's preferred timing, and we'll use it to indicate
* to the other layers that this mode is desired.
*/
struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
struct detailed_timing *timing)
{
struct drm_display_mode *mode;
struct detailed_pixel_timing *pt = &timing->data.pixel_data;
if (pt->stereo) {
printk(KERN_WARNING "stereo mode not supported\n");
return NULL;
}
if (!pt->separate_sync) {
printk(KERN_WARNING "integrated sync not supported\n");
return NULL;
}
mode = drm_mode_create(dev);
if (!mode)
return NULL;
mode->type = DRM_MODE_TYPE_DRIVER;
mode->clock = timing->pixel_clock * 10;
mode->hdisplay = (pt->hactive_hi << 8) | pt->hactive_lo;
mode->hsync_start = mode->hdisplay + ((pt->hsync_offset_hi << 8) |
pt->hsync_offset_lo);
mode->hsync_end = mode->hsync_start +
((pt->hsync_pulse_width_hi << 8) |
pt->hsync_pulse_width_lo);
mode->htotal = mode->hdisplay + ((pt->hblank_hi << 8) | pt->hblank_lo);
mode->vdisplay = (pt->vactive_hi << 8) | pt->vactive_lo;
mode->vsync_start = mode->vdisplay + ((pt->vsync_offset_hi << 8) |
pt->vsync_offset_lo);
mode->vsync_end = mode->vsync_start +
((pt->vsync_pulse_width_hi << 8) |
pt->vsync_pulse_width_lo);
mode->vtotal = mode->vdisplay + ((pt->vblank_hi << 8) | pt->vblank_lo);
drm_mode_set_name(mode);
if (pt->interlaced)
mode->flags |= V_INTERLACE;
mode->flags |= pt->hsync_positive ? V_PHSYNC : V_NHSYNC;
mode->flags |= pt->vsync_positive ? V_PVSYNC : V_NVSYNC;
return mode;
}
/*
* Detailed mode info for the EDID "established modes" data to use.
*/
static struct drm_display_mode edid_est_modes[] = {
{ DRM_MODE("800x600", DRM_MODE_TYPE_DRIVER, 40000, 800, 840,
968, 1056, 0, 600, 601, 605, 628, 0,
V_PHSYNC | V_PVSYNC) }, /* 800x600@60Hz */
{ DRM_MODE("800x600", DRM_MODE_TYPE_DRIVER, 36000, 800, 824,
896, 1024, 0, 600, 601, 603, 625, 0,
V_PHSYNC | V_PVSYNC) }, /* 800x600@56Hz */
{ DRM_MODE("640x480", DRM_MODE_TYPE_DRIVER, 31500, 640, 656,
720, 840, 0, 480, 481, 484, 500, 0,
V_NHSYNC | V_NVSYNC) }, /* 640x480@75Hz */
{ DRM_MODE("640x480", DRM_MODE_TYPE_DRIVER, 31500, 640, 664,
704, 832, 0, 480, 489, 491, 520, 0,
V_NHSYNC | V_NVSYNC) }, /* 640x480@72Hz */
{ DRM_MODE("640x480", DRM_MODE_TYPE_DRIVER, 30240, 640, 704,
768, 864, 0, 480, 483, 486, 525, 0,
V_NHSYNC | V_NVSYNC) }, /* 640x480@67Hz */
{ DRM_MODE("640x480", DRM_MODE_TYPE_DRIVER, 25200, 640, 656,
752, 800, 0, 480, 490, 492, 525, 0,
V_NHSYNC | V_NVSYNC) }, /* 640x480@60Hz */
{ DRM_MODE("720x400", DRM_MODE_TYPE_DRIVER, 35500, 720, 738,
846, 900, 0, 400, 421, 423, 449, 0,
V_NHSYNC | V_NVSYNC) }, /* 720x400@88Hz */
{ DRM_MODE("720x400", DRM_MODE_TYPE_DRIVER, 28320, 720, 738,
846, 900, 0, 400, 412, 414, 449, 0,
V_NHSYNC | V_PVSYNC) }, /* 720x400@70Hz */
{ DRM_MODE("1280x1024", DRM_MODE_TYPE_DRIVER, 135000, 1280, 1296,
1440, 1688, 0, 1024, 1025, 1028, 1066, 0,
V_PHSYNC | V_PVSYNC) }, /* 1280x1024@75Hz */
{ DRM_MODE("1024x768", DRM_MODE_TYPE_DRIVER, 78800, 1024, 1040,
1136, 1312, 0, 768, 769, 772, 800, 0,
V_PHSYNC | V_PVSYNC) }, /* 1024x768@75Hz */
{ DRM_MODE("1024x768", DRM_MODE_TYPE_DRIVER, 75000, 1024, 1048,
1184, 1328, 0, 768, 771, 777, 806, 0,
V_NHSYNC | V_NVSYNC) }, /* 1024x768@70Hz */
{ DRM_MODE("1024x768", DRM_MODE_TYPE_DRIVER, 65000, 1024, 1048,
1184, 1344, 0, 768, 771, 777, 806, 0,
V_NHSYNC | V_NVSYNC) }, /* 1024x768@60Hz */
{ DRM_MODE("1024x768", DRM_MODE_TYPE_DRIVER,44900, 1024, 1032,
1208, 1264, 0, 768, 768, 776, 817, 0,
V_PHSYNC | V_PVSYNC | V_INTERLACE) }, /* 1024x768@43Hz */
{ DRM_MODE("832x624", DRM_MODE_TYPE_DRIVER, 57284, 832, 864,
928, 1152, 0, 624, 625, 628, 667, 0,
V_NHSYNC | V_NVSYNC) }, /* 832x624@75Hz */
{ DRM_MODE("800x600", DRM_MODE_TYPE_DRIVER, 49500, 800, 816,
896, 1056, 0, 600, 601, 604, 625, 0,
V_PHSYNC | V_PVSYNC) }, /* 800x600@75Hz */
{ DRM_MODE("800x600", DRM_MODE_TYPE_DRIVER, 50000, 800, 856,
976, 1040, 0, 600, 637, 643, 666, 0,
V_PHSYNC | V_PVSYNC) }, /* 800x600@72Hz */
{ DRM_MODE("1152x864", DRM_MODE_TYPE_DRIVER, 108000, 1152, 1216,
1344, 1600, 0, 864, 865, 868, 900, 0,
V_PHSYNC | V_PVSYNC) }, /* 1152x864@75Hz */
};
#define EDID_EST_TIMINGS 16
#define EDID_STD_TIMINGS 8
#define EDID_DETAILED_TIMINGS 4
/**
* add_established_modes - get est. modes from EDID and add them
* @edid: EDID block to scan
*
* Each EDID block contains a bitmap of the supported "established modes" list
* (defined above). Tease them out and add them to the global modes list.
*/
static int add_established_modes(struct drm_output *output, struct edid *edid)
{
struct drm_device *dev = output->dev;
unsigned long est_bits = edid->established_timings.t1 |
(edid->established_timings.t2 << 8) |
((edid->established_timings.mfg_rsvd & 0x80) << 9);
int i, modes = 0;
for (i = 0; i <= EDID_EST_TIMINGS; i++)
if (est_bits & (1<<i)) {
struct drm_display_mode *newmode;
newmode = drm_mode_duplicate(dev, &edid_est_modes[i]);
if (newmode) {
drm_mode_probed_add(output, newmode);
modes++;
}
}
return modes;
}
/**
* add_standard_modes - get std. modes from EDID and add them
* @edid: EDID block to scan
*
* Standard modes can be calculated using the CVT standard. Grab them from
* @edid, calculate them, and add them to the list.
*/
static int add_standard_modes(struct drm_output *output, struct edid *edid)
{
struct drm_device *dev = output->dev;
int i, modes = 0;
for (i = 0; i < EDID_STD_TIMINGS; i++) {
struct std_timing *t = &edid->standard_timings[i];
struct drm_display_mode *newmode;
/* If std timings bytes are 1, 1 it's empty */
if (t->hsize == 1 && (t->aspect_ratio | t->vfreq) == 1)
continue;
newmode = drm_mode_std(dev, &edid->standard_timings[i]);
if (newmode) {
drm_mode_probed_add(output, newmode);
modes++;
}
}
return modes;
}
/**
* add_detailed_modes - get detailed mode info from EDID data
* @edid: EDID block to scan
*
* Some of the detailed timing sections may contain mode information. Grab
* it and add it to the list.
*/
static int add_detailed_info(struct drm_output *output, struct edid *edid)
{
struct drm_device *dev = output->dev;
int i, j, modes = 0;
for (i = 0; i < EDID_DETAILED_TIMINGS; i++) {
struct detailed_timing *timing = &edid->detailed_timings[i];
struct detailed_non_pixel *data = &timing->data.other_data;
struct drm_display_mode *newmode;
/* EDID up to and including 1.2 may put monitor info here */
if (edid->version == 1 && edid->revision < 3)
continue;
/* Detailed mode timing */
if (timing->pixel_clock) {
newmode = drm_mode_detailed(dev, timing);
/* First detailed mode is preferred */
if (newmode) {
if (i == 0 && edid->preferred_timing)
newmode->type |= DRM_MODE_TYPE_PREFERRED;
drm_mode_probed_add(output, newmode);
modes++;
}
continue;
}
/* Other timing or info */
switch (data->type) {
case EDID_DETAIL_MONITOR_SERIAL:
break;
case EDID_DETAIL_MONITOR_STRING:
break;
case EDID_DETAIL_MONITOR_RANGE:
/* Get monitor range data */
break;
case EDID_DETAIL_MONITOR_NAME:
break;
case EDID_DETAIL_MONITOR_CPDATA:
break;
case EDID_DETAIL_STD_MODES:
/* Five modes per detailed section */
for (j = 0; j < 5; i++) {
struct std_timing *std;
struct drm_display_mode *newmode;
std = &data->data.timings[j];
newmode = drm_mode_std(dev, std);
if (newmode) {
drm_mode_probed_add(output, newmode);
modes++;
}
}
break;
default:
break;
}
}
return modes;
}
#define DDC_ADDR 0x50
static unsigned char *drm_do_probe_ddc_edid(struct i2c_adapter *adapter)
{
unsigned char start = 0x0;
unsigned char *buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
struct i2c_msg msgs[] = {
{
.addr = DDC_ADDR,
.flags = 0,
.len = 1,
.buf = &start,
}, {
.addr = DDC_ADDR,
.flags = I2C_M_RD,
.len = EDID_LENGTH,
.buf = buf,
}
};
if (!buf) {
dev_warn(&adapter->dev, "unable to allocate memory for EDID "
"block.\n");
return NULL;
}
if (i2c_transfer(adapter, msgs, 2) == 2)
return buf;
dev_info(&adapter->dev, "unable to read EDID block.\n");
kfree(buf);
return NULL;
}
static unsigned char *drm_ddc_read(struct i2c_adapter *adapter)
{
struct i2c_algo_bit_data *algo_data = adapter->algo_data;
unsigned char *edid = NULL;
int i, j;
/*
* Startup the bus:
* Set clock line high (but give it time to come up)
* Then set clock & data low
*/
algo_data->setscl(algo_data->data, 1);
udelay(550); /* startup delay */
algo_data->setscl(algo_data->data, 0);
algo_data->setsda(algo_data->data, 0);
for (i = 0; i < 3; i++) {
/* For some old monitors we need the
* following process to initialize/stop DDC
*/
algo_data->setsda(algo_data->data, 0);
msleep(13);
algo_data->setscl(algo_data->data, 1);
for (j = 0; j < 5; j++) {
msleep(10);
if (algo_data->getscl(algo_data->data))
break;
}
if (j == 5)
continue;
algo_data->setsda(algo_data->data, 0);
msleep(15);
algo_data->setscl(algo_data->data, 0);
msleep(15);
algo_data->setsda(algo_data->data, 1);
msleep(15);
/* Do the real work */
edid = drm_do_probe_ddc_edid(adapter);
algo_data->setsda(algo_data->data, 0);
algo_data->setscl(algo_data->data, 0);
msleep(15);
algo_data->setscl(algo_data->data, 1);
for (j = 0; j < 10; j++) {
msleep(10);
if (algo_data->getscl(algo_data->data))
break;
}
algo_data->setsda(algo_data->data, 1);
msleep(15);
algo_data->setscl(algo_data->data, 0);
if (edid)
break;
}
/* Release the DDC lines when done or the Apple Cinema HD display
* will switch off
*/
algo_data->setsda(algo_data->data, 0);
algo_data->setscl(algo_data->data, 0);
algo_data->setscl(algo_data->data, 1);
return edid;
}
/**
* drm_get_edid - get EDID data, if available
* @output: output we're probing
* @adapter: i2c adapter to use for DDC
*
* Poke the given output's i2c channel to grab EDID data if possible.
*
* Return edid data or NULL if we couldn't find any.
*/
struct edid *drm_get_edid(struct drm_output *output,
struct i2c_adapter *adapter)
{
struct edid *edid;
edid = (struct edid *)drm_ddc_read(adapter);
if (!edid) {
dev_warn(&output->dev->pdev->dev, "%s: no EDID data\n",
drm_get_output_name(output));
return NULL;
}
if (!edid_valid(edid)) {
dev_warn(&output->dev->pdev->dev, "%s: EDID invalid.\n",
drm_get_output_name(output));
kfree(edid);
return NULL;
}
return edid;
}
EXPORT_SYMBOL(drm_get_edid);
/**
* drm_add_edid_modes - add modes from EDID data, if available
* @output: output we're probing
* @edid: edid data
*
* Add the specified modes to the output's mode list.
*
* Return number of modes added or 0 if we couldn't find any.
*/
int drm_add_edid_modes(struct drm_output *output, struct edid *edid)
{
int num_modes = 0;
if (edid == NULL) {
return 0;
}
if (!edid_valid(edid)) {
dev_warn(&output->dev->pdev->dev, "%s: EDID invalid.\n",
drm_get_output_name(output));
return 0;
}
num_modes += add_established_modes(output, edid);
num_modes += add_standard_modes(output, edid);
num_modes += add_detailed_info(output, edid);
return num_modes;
}
EXPORT_SYMBOL(drm_add_edid_modes);