From 61f11699e7a92d932b31ded3715ad4f70eb26ef2 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Sat, 30 May 2009 20:42:27 -0700 Subject: [PATCH] drm: Eliminate magic I2C frobbing when reading EDID This code depends on the underlying I2C adapter using the bit-banging algo, which may not be the case. If specific encoders require this mechanism, they should build a custom I2C algo that implements this workaround, rather than having it in the general path. Signed-off-by: Keith Packard Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_edid.c | 74 +--------------------------------------------- 1 file changed, 1 insertion(+), 73 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index ca9c616..c4d9b33 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -584,85 +584,13 @@ int drm_do_probe_ddc_edid(struct i2c_adapter *adapter, } EXPORT_SYMBOL(drm_do_probe_ddc_edid); -/** - * Get EDID information. - * - * \param adapter : i2c device adaptor. - * \param buf : EDID data buffer to be filled - * \param len : EDID data buffer length - * \return 0 on success or -1 on failure. - * - * Initialize DDC, then fetch EDID information - * by calling drm_do_probe_ddc_edid function. - */ -static int drm_ddc_read(struct i2c_adapter *adapter, - unsigned char *buf, int len) -{ - struct i2c_algo_bit_data *algo_data = adapter->algo_data; - int i, j; - int ret = -1; - - algo_data->setscl(algo_data->data, 1); - - for (i = 0; i < 1; 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 */ - ret = drm_do_probe_ddc_edid(adapter, buf, len); - 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 (ret == 0) - 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); - - return ret; -} - static int drm_ddc_read_edid(struct drm_connector *connector, struct i2c_adapter *adapter, char *buf, int len) { int ret; - ret = drm_ddc_read(adapter, buf, len); + ret = drm_do_probe_ddc_edid(adapter, buf, len); if (ret != 0) { dev_info(&connector->dev->pdev->dev, "%s: no EDID data\n", drm_get_connector_name(connector)); -- 2.7.4