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authorTomi Valkeinen <tomi.valkeinen@ti.com>2014-02-13 15:31:38 +0200
committerTomi Valkeinen <tomi.valkeinen@ti.com>2014-04-17 08:10:19 +0300
commitf7018c21350204c4cf628462f229d44d03545254 (patch)
tree408787177164cf51cc06f7aabdb04fcff8d2b6aa /drivers/video/fbdev/fb_ddc.c
parentc26ef3eb3c11274bad1b64498d0a134f85755250 (diff)
video: move fbdev to drivers/video/fbdev
The drivers/video directory is a mess. It contains generic video related files, directories for backlight, console, linux logo, lots of fbdev device drivers, fbdev framework files. Make some order into the chaos by creating drivers/video/fbdev directory, and move all fbdev related files there. No functionality is changed, although I guess it is possible that some subtle Makefile build order related issue could be created by this patch. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Rob Clark <robdclark@gmail.com> Acked-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/video/fbdev/fb_ddc.c')
-rw-r--r--drivers/video/fbdev/fb_ddc.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/drivers/video/fbdev/fb_ddc.c b/drivers/video/fbdev/fb_ddc.c
new file mode 100644
index 000000000000..2b106f046fde
--- /dev/null
+++ b/drivers/video/fbdev/fb_ddc.c
@@ -0,0 +1,119 @@
+/*
+ * drivers/video/fb_ddc.c - DDC/EDID read support.
+ *
+ * Copyright (C) 2006 Dennis Munsie <dmunsie@cecropia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/fb.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/slab.h>
+
+#include "edid.h"
+
+#define DDC_ADDR 0x50
+
+static unsigned char *fb_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_warn(&adapter->dev, "unable to read EDID block.\n");
+ kfree(buf);
+ return NULL;
+}
+
+unsigned char *fb_ddc_read(struct i2c_adapter *adapter)
+{
+ struct i2c_algo_bit_data *algo_data = adapter->algo_data;
+ unsigned char *edid = NULL;
+ int i, j;
+
+ algo_data->setscl(algo_data->data, 1);
+
+ 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, 1);
+ 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 = fb_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);
+ algo_data->setsda(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, 1);
+ algo_data->setscl(algo_data->data, 1);
+
+ adapter->class |= I2C_CLASS_DDC;
+ return edid;
+}
+
+EXPORT_SYMBOL_GPL(fb_ddc_read);
+
+MODULE_AUTHOR("Dennis Munsie <dmunsie@cecropia.com>");
+MODULE_DESCRIPTION("DDC/EDID reading support");
+MODULE_LICENSE("GPL");