[Intel-gfx] [MIPI SEQ PARSING v3 01/13] drm/i915: Adding the parsing logic for the i2c element

[Deepak M]

From: vkorjani <vikas.korjani at intel.com>

New sequence element for i2c is been added in the
mipi sequence block of the VBT. This patch parses
and executes the i2c sequence.

v2: Add i2c_put_adapter call(Jani), rebase
v3: corrected the retry loop(Jani), rebase

Cc: Jani Nikula <jani.nikula at intel.com>
Signed-off-by: vkorjani <vikas.korjani at intel.com>
Signed-off-by: Deepak M <m.deepak at intel.com>
---
 drivers/gpu/drm/i915/intel_bios.c          |  6 +++
 drivers/gpu/drm/i915/intel_bios.h          |  1 +
 drivers/gpu/drm/i915/intel_dsi_panel_vbt.c | 60 ++++++++++++++++++++++++++++++
 3 files changed, 67 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index ce82f9c..6756a1c 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -718,6 +718,12 @@ static u8 *goto_next_sequence(u8 *data, int *size)
 
 			data += 3;
 			break;
+		case MIPI_SEQ_ELEM_I2C:
+			/* skip by this element payload size */
+			data += 7;
+			len = *data;
+			data += len + 1;
+			break;
 		default:
 			DRM_ERROR("Unknown element\n");
 			return NULL;
diff --git a/drivers/gpu/drm/i915/intel_bios.h b/drivers/gpu/drm/i915/intel_bios.h
index 7ec8c9a..4ec73f5 100644
--- a/drivers/gpu/drm/i915/intel_bios.h
+++ b/drivers/gpu/drm/i915/intel_bios.h
@@ -954,6 +954,7 @@ enum mipi_seq_element {
 	MIPI_SEQ_ELEM_SEND_PKT,
 	MIPI_SEQ_ELEM_DELAY,
 	MIPI_SEQ_ELEM_GPIO,
+	MIPI_SEQ_ELEM_I2C,
 	MIPI_SEQ_ELEM_STATUS,
 	MIPI_SEQ_ELEM_MAX
 };
diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
index a5e99ac..92d619a 100644
--- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
+++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
@@ -31,6 +31,7 @@
 #include <drm/drm_panel.h>
 #include <linux/slab.h>
 #include <video/mipi_display.h>
+#include <linux/i2c.h>
 #include <asm/intel-mid.h>
 #include <video/mipi_display.h>
 #include "i915_drv.h"
@@ -104,6 +105,64 @@ static struct gpio_table gtable[] = {
 	{ GPIO_NC_11_PCONF0, GPIO_NC_11_PAD, 0}
 };
 
+static const u8 *mipi_exec_i2c(struct intel_dsi *intel_dsi, const u8 *data)
+{
+	struct i2c_adapter *adapter;
+	int ret;
+	u8 reg_offset, payload_size, retries = 5;
+	struct i2c_msg msg;
+	u8 *transmit_buffer = NULL;
+	u8 flag = *data++;
+	u8 index = *data++;
+	u8 bus_number = *data++;
+	u16 slave_add = *(u16 *)(data);
+
+	data = data + 2;
+	reg_offset = *data++;
+	payload_size = *data++;
+
+	adapter = i2c_get_adapter(bus_number);
+
+	if (!adapter) {
+		DRM_ERROR("i2c_get_adapter(%u)\n", bus_number);
+		goto out;
+	}
+
+	transmit_buffer = kmalloc(1 + payload_size, GFP_TEMPORARY);
+
+	if (!transmit_buffer)
+		goto out;
+
+	transmit_buffer[0] = reg_offset;
+	memcpy(&transmit_buffer[1], data, payload_size);
+
+	msg.addr   = slave_add;
+	msg.flags  = 0;
+	msg.len    = payload_size + 1;
+	msg.buf    = &transmit_buffer[0];
+
+	do {
+		ret =  i2c_transfer(adapter, &msg, 1);
+		if (ret == 1)
+			goto out;
+		else if (ret == -EAGAIN)
+			usleep_range(1000, 2500);
+		else {
+			DRM_ERROR("i2c transfer failed, error code:%d\n", ret);
+			goto out;
+		}
+	} while (retries--);
+
+	if (retries == 0)
+		DRM_ERROR("i2c transfer failed, error code:%d\n", ret);
+out:
+	kfree(transmit_buffer);
+	i2c_put_adapter(adapter);
+
+	data = data + payload_size;
+	return data;
+}
+
 static inline enum port intel_dsi_seq_port_to_port(u8 port)
 {
 	return port ? PORT_C : PORT_A;
@@ -236,6 +295,7 @@ static const fn_mipi_elem_exec exec_elem[] = {
 	mipi_exec_send_packet,
 	mipi_exec_delay,
 	mipi_exec_gpio,
+	mipi_exec_i2c,
 	NULL, /* status read; later */
 };
 
-- 
1.9.1