The change adds support of internal HDMI I2C master controller, this
subdevice is used by default, if "ddc-i2c-bus" DT property is omitted.
The main purpose of this functionality is to support reading EDID from
an HDMI monitor on boards, which don't have an I2C bus connected to
DDC pins.
Signed-off-by: Vladimir Zapolskiy
---
drivers/gpu/drm/bridge/dw_hdmi.c | 332 ++-
1 file changed, 326 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c
index 49cafb6..2a52449 100644
--- a/drivers/gpu/drm/bridge/dw_hdmi.c
+++ b/drivers/gpu/drm/bridge/dw_hdmi.c
@@ -1,15 +1,17 @@
/*
+ * DesignWare High-Definition Multimedia Interface (HDMI) driver
+ *
+ * Copyright (C) 2013-2015 Mentor Graphics Inc.
* Copyright (C) 2011-2013 Freescale Semiconductor, Inc.
+ * Copyright (C) 2010, Guennadi Liakhovetski
*
* 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.
*
- * Designware High-Definition Multimedia Interface (HDMI) driver
- *
- * Copyright (C) 2010, Guennadi Liakhovetski
*/
+
#include
#include
#include
@@ -28,6 +30,26 @@
#include "dw_hdmi.h"
+/* HDMI_IH_I2CM_STAT0 and HDMI_IH_MUTE_I2CM_STAT0 register bits */
+#define HDMI_IH_I2CM_STAT0_ERROR BIT(0)
+#define HDMI_IH_I2CM_STAT0_DONEBIT(1)
+
+/* HDMI_I2CM_OPERATION register bits */
+#define HDMI_I2CM_OPERATION_READ BIT(0)
+#define HDMI_I2CM_OPERATION_READ_EXT BIT(1)
+#define HDMI_I2CM_OPERATION_WRITE BIT(4)
+
+/* HDMI_I2CM_INT register bits */
+#define HDMI_I2CM_INT_DONE_MASKBIT(2)
+#define HDMI_I2CM_INT_DONE_POL BIT(3)
+
+/* HDMI_I2CM_CTLINT register bits */
+#define HDMI_I2CM_CTLINT_ARB_MASK BIT(2)
+#define HDMI_I2CM_CTLINT_ARB_POL BIT(3)
+#define HDMI_I2CM_CTLINT_NAC_MASK BIT(6)
+#define HDMI_I2CM_CTLINT_NAC_POL BIT(7)
+
+
#define HDMI_EDID_LEN 512
#define RGB0
@@ -102,6 +124,17 @@ struct hdmi_data_info {
struct hdmi_vmode video_mode;
};
+struct dw_hdmi_i2c {
+ struct i2c_adapter adap;
+
+ spinlock_t lock;
+ struct completion cmp;
+ u8 stat;
+
+ u8 slave_reg;
+ boolis_regaddr;
+};
+
struct dw_hdmi {
struct drm_connector connector;
struct drm_encoder *encoder;
@@ -111,6 +144,7 @@ struct dw_hdmi {
struct device *dev;
struct clk *isfr_clk;
struct clk *iahb_clk;
+ struct dw_hdmi_i2c *i2c;
struct hdmi_data_info hdmi_data;
const struct dw_hdmi_plat_data *plat_data;
@@ -179,6 +213,242 @@ static void hdmi_mask_writeb(struct dw_hdmi *hdmi, u8
data, unsigned int reg,
hdmi_modb(hdmi, data << shift, mask, reg);
}
+static void dw_hdmi_i2c_init(struct dw_hdmi *hdmi)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(>i2c->lock, flags);
+
+ /* Set Fast Mode speed */
+ hdmi_writeb(hdmi, 0x0b, HDMI_I2CM_DIV);
+
+ /* Software reset */
+ hdmi_writeb(hdmi, 0x00, HDMI_I2CM_SOFTRSTZ);
+
+ /* Set done, not acknowledged and arbitration interrupt polarities */
+ hdmi_writeb(hdmi, HDMI_I2CM_INT_DONE_POL, HDMI_I2CM_INT);
+ hdmi_writeb(hdmi, HDMI_I2CM_CTLINT_NAC_POL | HDMI_I2CM_CTLINT_ARB_POL,
+ HDMI_I2CM_CTLINT);
+
+ /* Clear DONE and ERROR interrupts */
+ hdmi_writeb(hdmi, HDMI_IH_I2CM_STAT0_ERROR | HDMI_IH_I2CM_STAT0_DONE,
+ HDMI_IH_I2CM_STAT0);
+
+ /* Mute DONE and ERROR interrupts */
+ hdmi_writeb(hdmi, HDMI_IH_I2CM_STAT0_ERROR | HDMI_IH_I2CM_STAT0_DONE,
+ HDMI_IH_MUTE_I2CM_STAT0);
+
+ spin_unlock_irqrestore(>i2c->lock, flags);
+}
+
+static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
+ unsigned char *buf, int length)
+{
+ int stat;
+ unsigned long flags;
+ struct dw_hdmi_i2c *i2c = hdmi->i2c;
+
+ spin_lock_irqsave(>lock, flags);
+
+ if (!i2c->is_regaddr) {
+ dev_dbg(hdmi->dev, "set read register address to 0\n");
+ i2c->slave_reg = 0x00;
+ i2c->is_regaddr = true;
+ }
+
+ while (length--) {
+ hdmi_writeb(hdmi, i2c->slave_reg++, HDMI_I2CM_ADDRESS);
+ hdmi_writeb(hdmi,
+ HDMI_I2CM_OPERATION_READ, HDMI_I2CM_OPERATION);
+ i2c->stat = 0;
+
+ spin_unlock_irqrestore(>lock, flags);
+
+ stat = wait_for_completion_interruptible_timeout(>cmp,
+HZ / 10);
+ if (!stat)
+
