udldrmfb: udl_get_edid: drop unneeded i--
[linux-2.6.git] / drivers / gpu / drm / udl / udl_connector.c
1 /*
2  * Copyright (C) 2012 Red Hat
3  * based in parts on udlfb.c:
4  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
5  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
6  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License v2. See the file COPYING in the main directory of this archive for
10  * more details.
11  */
12
13 #include "drmP.h"
14 #include "drm_crtc.h"
15 #include "drm_edid.h"
16 #include "drm_crtc_helper.h"
17 #include "udl_drv.h"
18
19 /* dummy connector to just get EDID,
20    all UDL appear to have a DVI-D */
21
22 static u8 *udl_get_edid(struct udl_device *udl)
23 {
24         u8 *block;
25         char *rbuf;
26         int ret, i;
27
28         block = kmalloc(EDID_LENGTH, GFP_KERNEL);
29         if (block == NULL)
30                 return NULL;
31
32         rbuf = kmalloc(2, GFP_KERNEL);
33         if (rbuf == NULL)
34                 goto error;
35
36         for (i = 0; i < EDID_LENGTH; i++) {
37                 ret = usb_control_msg(udl->ddev->usbdev,
38                                       usb_rcvctrlpipe(udl->ddev->usbdev, 0), (0x02),
39                                       (0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
40                                       HZ);
41                 if (ret < 1) {
42                         DRM_ERROR("Read EDID byte %d failed err %x\n", i, ret);
43                         goto error;
44                 }
45                 block[i] = rbuf[1];
46         }
47
48         kfree(rbuf);
49         return block;
50
51 error:
52         kfree(block);
53         kfree(rbuf);
54         return NULL;
55 }
56
57 static int udl_get_modes(struct drm_connector *connector)
58 {
59         struct udl_device *udl = connector->dev->dev_private;
60         struct edid *edid;
61         int ret;
62
63         edid = (struct edid *)udl_get_edid(udl);
64
65         connector->display_info.raw_edid = (char *)edid;
66
67         /*
68          * We only read the main block, but if the monitor reports extension
69          * blocks then the drm edid code expects them to be present, so patch
70          * the extension count to 0.
71          */
72         edid->checksum += edid->extensions;
73         edid->extensions = 0;
74
75         drm_mode_connector_update_edid_property(connector, edid);
76         ret = drm_add_edid_modes(connector, edid);
77         connector->display_info.raw_edid = NULL;
78         kfree(edid);
79         return ret;
80 }
81
82 static int udl_mode_valid(struct drm_connector *connector,
83                           struct drm_display_mode *mode)
84 {
85         struct udl_device *udl = connector->dev->dev_private;
86         if (!udl->sku_pixel_limit)
87                 return 0;
88
89         if (mode->vdisplay * mode->hdisplay > udl->sku_pixel_limit)
90                 return MODE_VIRTUAL_Y;
91
92         return 0;
93 }
94
95 static enum drm_connector_status
96 udl_detect(struct drm_connector *connector, bool force)
97 {
98         if (drm_device_is_unplugged(connector->dev))
99                 return connector_status_disconnected;
100         return connector_status_connected;
101 }
102
103 struct drm_encoder *udl_best_single_encoder(struct drm_connector *connector)
104 {
105         int enc_id = connector->encoder_ids[0];
106         struct drm_mode_object *obj;
107         struct drm_encoder *encoder;
108
109         obj = drm_mode_object_find(connector->dev, enc_id, DRM_MODE_OBJECT_ENCODER);
110         if (!obj)
111                 return NULL;
112         encoder = obj_to_encoder(obj);
113         return encoder;
114 }
115
116 int udl_connector_set_property(struct drm_connector *connector, struct drm_property *property,
117                                uint64_t val)
118 {
119         return 0;
120 }
121
122 static void udl_connector_destroy(struct drm_connector *connector)
123 {
124         drm_sysfs_connector_remove(connector);
125         drm_connector_cleanup(connector);
126         kfree(connector);
127 }
128
129 struct drm_connector_helper_funcs udl_connector_helper_funcs = {
130         .get_modes = udl_get_modes,
131         .mode_valid = udl_mode_valid,
132         .best_encoder = udl_best_single_encoder,
133 };
134
135 struct drm_connector_funcs udl_connector_funcs = {
136         .dpms = drm_helper_connector_dpms,
137         .detect = udl_detect,
138         .fill_modes = drm_helper_probe_single_connector_modes,
139         .destroy = udl_connector_destroy,
140         .set_property = udl_connector_set_property,
141 };
142
143 int udl_connector_init(struct drm_device *dev, struct drm_encoder *encoder)
144 {
145         struct drm_connector *connector;
146
147         connector = kzalloc(sizeof(struct drm_connector), GFP_KERNEL);
148         if (!connector)
149                 return -ENOMEM;
150
151         drm_connector_init(dev, connector, &udl_connector_funcs, DRM_MODE_CONNECTOR_DVII);
152         drm_connector_helper_add(connector, &udl_connector_helper_funcs);
153
154         drm_sysfs_connector_add(connector);
155         drm_mode_connector_attach_encoder(connector, encoder);
156
157         drm_connector_attach_property(connector,
158                                       dev->mode_config.dirty_info_property,
159                                       1);
160         return 0;
161 }