<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<style>
font{
line-height: 1.6;
}
ul,ol{
padding-left: 20px;
list-style-position: inside;
}
</style>
<div style="font-family:Helvetica,Helvetica,微软雅黑, 宋体; line-height:1.6;">
<div></div><div>
<div><pre wrap="soft" style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); overflow-wrap: break-word;">Implement use GPIO and I2C driver to detect connector
and fetch EDID via DDC.
v5:
- Use braidge->ddc to get EDID and detect connector.
v4:
- Delete the gpio_chip subsystem call.
- Delete some redundant prints.
v3:
- Change some driver log to the drm_ version.
v2:
- Optimize the error handling process.
- Delete loongson_i2c_bus_match and loongson_i2c_add function.
- Optimize part of the code flow.
Signed-off-by: Yi Li <liyi@loongson.cn>
Signed-off-by: Chenyang Li <lichenyang@loongson.cn>
---
drivers/gpu/drm/loongson/Makefile | 1 +
drivers/gpu/drm/loongson/loongson_drv.c | 11 +-
drivers/gpu/drm/loongson/loongson_drv.h | 7 +
drivers/gpu/drm/loongson/loongson_encoder.c | 31 +++-
drivers/gpu/drm/loongson/loongson_i2c.c | 189 ++++++++++++++++++++
drivers/gpu/drm/loongson/loongson_i2c.h | 31 ++++
6 files changed, 261 insertions(+), 9 deletions(-)
create mode 100644 drivers/gpu/drm/loongson/loongson_i2c.c
create mode 100644 drivers/gpu/drm/loongson/loongson_i2c.h
diff --git a/drivers/gpu/drm/loongson/Makefile b/drivers/gpu/drm/loongson/Makefile
index 534a64047fb6..4a5fab7d000b 100644
--- a/drivers/gpu/drm/loongson/Makefile
+++ b/drivers/gpu/drm/loongson/Makefile
@@ -9,5 +9,6 @@ loongson-y := loongson_connector.o \
loongson_device.o \
loongson_drv.o \
loongson_encoder.o \
+ loongson_i2c.o \
loongson_plane.o
obj-$(CONFIG_DRM_LOONGSON) += loongson.o
diff --git a/drivers/gpu/drm/loongson/loongson_drv.c b/drivers/gpu/drm/loongson/loongson_drv.c
index 3db298293865..9120d8188ddf 100644
--- a/drivers/gpu/drm/loongson/loongson_drv.c
+++ b/drivers/gpu/drm/loongson/loongson_drv.c
@@ -20,9 +20,10 @@
/* Interface history:
* 0.1 - original.
+ * 0.2 - add i2c and connector detect.
*/
#define DRIVER_MAJOR 0
-#define DRIVER_MINOR 1
+#define DRIVER_MINOR 2
static const struct drm_mode_config_funcs loongson_mode_funcs = {
.fb_create = drm_gem_fb_create,
@@ -86,6 +87,14 @@ static int loongson_device_init(struct drm_device *dev)
ldev->num_crtc = 2;
+ ret = loongson_dc_gpio_init(ldev);
+ if (ret)
+ return ret;
+
+ ret = loongson_i2c_init(ldev);
+ if (ret)
+ return ret;
+
drm_info(dev, "DC mmio base 0x%llx size 0x%llx io 0x%llx\n",
mmio_base, mmio_size, *(u64 *)ldev->io);
drm_info(dev, "GPU vram start = 0x%x size = 0x%x\n",
diff --git a/drivers/gpu/drm/loongson/loongson_drv.h b/drivers/gpu/drm/loongson/loongson_drv.h
index feb254ae8c32..e8ca0eac827c 100644
--- a/drivers/gpu/drm/loongson/loongson_drv.h
+++ b/drivers/gpu/drm/loongson/loongson_drv.h
@@ -8,6 +8,8 @@
#include <drm/drm_gem_vram_helper.h>
#include <drm/drm_bridge.h>
+#include "loongson_i2c.h"
+
/* General customization:
*/
#define DRIVER_AUTHOR "Loongson graphics driver team"
@@ -100,6 +102,8 @@ struct loongson_device {
u32 num_crtc;
struct loongson_mode_info mode_info[2];
struct pci_dev *gpu_pdev; /* LS7A gpu device info */
+
+ struct loongson_i2c i2c_bus[DC_MAX_I2C_BUS];
};
static inline struct loongson_device *to_loongson_device(struct drm_device *dev)
@@ -119,6 +123,9 @@ int loongson_encoder_init(struct loongson_device *ldev, int index);
/* plane */
struct loongson_plane *loongson_plane_init(struct drm_device *dev, int index);
+/* i2c */
+int loongson_dc_gpio_init(struct loongson_device *ldev);
+
/* device */
u32 loongson_gpu_offset(struct drm_plane_state *state,
struct loongson_device *dev);
diff --git a/drivers/gpu/drm/loongson/loongson_encoder.c b/drivers/gpu/drm/loongson/loongson_encoder.c
index 0645a645cb9d..f07c39e1713b 100644
--- a/drivers/gpu/drm/loongson/loongson_encoder.c
+++ b/drivers/gpu/drm/loongson/loongson_encoder.c
@@ -6,19 +6,31 @@
#include "loongson_drv.h"
-static int loongson_bridge_get_modes(struct drm_bridge *bridge,
- struct drm_connector *connector)
+enum drm_connector_status loongson_bridge_detect(struct drm_bridge *bridge)
{
- int count;
+ unsigned char start = 0x0;
+ struct i2c_msg msgs = {
+ .addr = DDC_ADDR,
+ .flags = 0,
+ .len = 1,
+ .buf = &start,
+ };
- count = drm_add_modes_noedid(connector, 1920, 1080);
- drm_set_preferred_mode(connector, 1024, 768);
+ if (i2c_transfer(bridge->ddc, &msgs, 1) != 1)
+ return connector_status_disconnected;
+ else
+ return connector_status_connected;
+}
- return count;
+static struct edid *loongson_bridge_get_edid(struct drm_bridge *bridge,
+ struct drm_connector *connector)
+{
+ return drm_get_edid(connector, bridge->ddc);
}
static const struct drm_bridge_funcs loongson_encoder_bridge_funcs = {
- .get_modes = loongson_bridge_get_modes,
+ .detect = loongson_bridge_detect,
+ .get_edid = loongson_bridge_get_edid,
.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
.atomic_reset = drm_atomic_helper_bridge_reset,
@@ -39,7 +51,10 @@ int loongson_encoder_init(struct loongson_device *ldev, int index)
ldev->mode_info[index].encoder = lencoder;
lencoder->bridge.funcs = &loongson_encoder_bridge_funcs;
- lencoder->bridge.ops = DRM_BRIDGE_OP_MODES;
+ lencoder->bridge.ddc = ldev->i2c_bus[index].adapter;
+ lencoder->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID
+ | DRM_BRIDGE_OP_MODES;
+
if (index == 0)
lencoder->bridge.type = DRM_MODE_CONNECTOR_VGA;
else if (index == 1)
diff --git a/drivers/gpu/drm/loongson/loongson_i2c.c b/drivers/gpu/drm/loongson/loongson_i2c.c
new file mode 100644
index 000000000000..9f2b99159dd0
--- /dev/null
+++ b/drivers/gpu/drm/loongson/loongson_i2c.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Copyright (C) 2022 Loongson Inc. */
+
+#include "loongson_drv.h"
+#include "loongson_i2c.h"
+
+static inline void dc_gpio_set_dir(struct loongson_device *ldev,
+ unsigned int pin, int input)
+{
+ u32 temp;
+
+ temp = ls7a_mm_rreg(ldev, LS7A_DC_GPIO_CFG_OFFSET);
+ if (input)
+ temp |= 1UL << pin;
+ else
+ temp &= ~(1UL << pin);
+
+ ls7a_mm_wreg(ldev, LS7A_DC_GPIO_CFG_OFFSET, temp);
+}
+
+static void dc_gpio_set_val(struct loongson_device *ldev, unsigned int pin,
+ int high)
+{
+ u32 temp;
+
+ temp = ls7a_mm_rreg(ldev, LS7A_DC_GPIO_OUT_OFFSET);
+ if (high)
+ temp |= 1UL << pin;
+ else
+ temp &= ~(1UL << pin);
+
+ ls7a_mm_wreg(ldev, LS7A_DC_GPIO_OUT_OFFSET, temp);
+}
+
+static void loongson_i2c_set_data(void *i2c, int value)
+{
+ struct loongson_i2c *li2c = i2c;
+ struct loongson_device *ldev = li2c->ldev;
+ unsigned int pin = li2c->data;
+
+ if (value)
+ dc_gpio_set_dir(ldev, pin, 1);
+ else {
+ dc_gpio_set_val(ldev, pin, 0);
+ dc_gpio_set_dir(ldev, pin, 0);
+ }
+}
+
+static void loongson_i2c_set_clock(void *i2c, int value)
+{
+ struct loongson_i2c *li2c = i2c;
+ struct loongson_device *ldev = li2c->ldev;
+ unsigned int pin = li2c->clock;
+
+ if (value)
+ dc_gpio_set_dir(ldev, pin, 1);
+ else {
+ dc_gpio_set_val(ldev, pin, 0);
+ dc_gpio_set_dir(ldev, pin, 0);
+ }
+}
+
+static int loongson_i2c_get_data(void *i2c)
+{
+ int val;
+ struct loongson_i2c *li2c = i2c;
+ struct loongson_device *ldev = li2c->ldev;
+ unsigned int pin = li2c->data;
+
+ val = ls7a_mm_rreg(ldev, LS7A_DC_GPIO_IN_OFFSET);
+
+ return (val >> pin) & 1;
+}
+
+static int loongson_i2c_get_clock(void *i2c)
+{
+ int val;
+ struct loongson_i2c *li2c = i2c;
+ struct loongson_device *ldev = li2c->ldev;
+ unsigned int pin = li2c->clock;
+
+ val = ls7a_mm_rreg(ldev, LS7A_DC_GPIO_IN_OFFSET);
+
+ return (val >> pin) & 1;
+}
+
+static int loongson_i2c_create(struct loongson_device *ldev,
+ struct loongson_i2c *li2c, const char *name)
+{
+ int ret;
+ unsigned int i2c_num;
+ struct drm_device *dev = &ldev->dev;
+ struct i2c_client *i2c_cli;
+ struct i2c_adapter *i2c_adapter;
+ struct i2c_algo_bit_data *i2c_algo_data;
+ const struct i2c_board_info i2c_info = {
+ .type = "ddc-dev",
+ .addr = DDC_ADDR,
+ .flags = I2C_CLASS_DDC,
+ };
+
+ i2c_num = li2c->i2c_id;
+ i2c_adapter = devm_kzalloc(dev->dev, sizeof(*i2c_adapter), GFP_KERNEL);
+ if (!i2c_adapter)
+ return -ENOMEM;
+
+ i2c_algo_data = devm_kzalloc(dev->dev, sizeof(*i2c_algo_data), GFP_KERNEL);
+ if (!i2c_algo_data) {
+ ret = -ENOMEM;
+ goto free_adapter;
+ }
+
+ i2c_adapter->owner = THIS_MODULE;
+ i2c_adapter->class = I2C_CLASS_DDC;
+ i2c_adapter->algo_data = i2c_algo_data;
+ i2c_adapter->dev.parent = dev->dev;
+ i2c_adapter->nr = -1;
+ snprintf(i2c_adapter->name, sizeof(i2c_adapter->name), "%s%d",
+ name, i2c_num);
+
+ li2c->data = i2c_num * 2;
+ li2c->clock = i2c_num * 2 + 1;
+ DRM_INFO("Created i2c-%d, sda=%d, scl=%d\n",
+ i2c_num, li2c->data, li2c->clock);
+
+ i2c_algo_data->setsda = loongson_i2c_set_data;
+ i2c_algo_data->setscl = loongson_i2c_set_clock;
+ i2c_algo_data->getsda = loongson_i2c_get_data;
+ i2c_algo_data->getscl = loongson_i2c_get_clock;
+ i2c_algo_data->udelay = DC_I2C_TON;
+ i2c_algo_data->timeout = usecs_to_jiffies(2200);
+
+ ret = i2c_bit_add_numbered_bus(i2c_adapter);
+ if (ret)
+ goto free_algo_data;
+
+ li2c->adapter = i2c_adapter;
+ i2c_algo_data->data = li2c;
+ i2c_set_adapdata(li2c->adapter, li2c);
+ li2c->ldev = ldev;
+ DRM_INFO("Register i2c algo-bit adapter [%s]\n", i2c_adapter->name);
+
+ i2c_cli = i2c_new_client_device(i2c_adapter, &i2c_info);
+ if (IS_ERR(i2c_cli)) {
+ ret = PTR_ERR(i2c_cli);
+ goto remove_i2c_adapter;
+ }
+
+ return 0;
+
+remove_i2c_adapter:
+ drm_err(dev, "Failed to create i2c client\n");
+ i2c_del_adapter(i2c_adapter);
+free_algo_data:
+ drm_err(dev, "Failed to register i2c adapter %s\n", i2c_adapter->name);
+ kfree(i2c_algo_data);
+free_adapter:
+ kfree(i2c_adapter);
+
+ return ret;
+}
+
+int loongson_dc_gpio_init(struct loongson_device *ldev)
+{
+ int pin;
+
+ /* set gpio dir output 0-3 */
+ for (pin = 0; pin < 4; pin++) {
+ dc_gpio_set_val(ldev, pin, 0);
+ dc_gpio_set_dir(ldev, pin, 0);
+ }
+
+ return 0;
+}
+
+int loongson_i2c_init(struct loongson_device *ldev)
+{
+ int ret;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ ldev->i2c_bus[1].i2c_id = i;
+ ret = loongson_i2c_create(ldev, &ldev->i2c_bus[i], DC_I2C_NAME);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
diff --git a/drivers/gpu/drm/loongson/loongson_i2c.h b/drivers/gpu/drm/loongson/loongson_i2c.h
new file mode 100644
index 000000000000..c6c9c564fec4
--- /dev/null
+++ b/drivers/gpu/drm/loongson/loongson_i2c.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2022 Loongson Inc. */
+
+#ifndef __LOONGSON_I2C_H__
+#define __LOONGSON_I2C_H__
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+
+#include <drm/drm_edid.h>
+
+#define DC_I2C_TON 5
+#define DC_I2C_NAME "ls_dc_i2c"
+#define DC_MAX_I2C_BUS 2
+
+#define LS7A_DC_GPIO_CFG_OFFSET (0x1660)
+#define LS7A_DC_GPIO_IN_OFFSET (0x1650)
+#define LS7A_DC_GPIO_OUT_OFFSET (0x1650)
+
+struct loongson_device;
+struct loongson_i2c {
+ struct loongson_device *ldev;
+ struct i2c_adapter *adapter;
+ u32 data;
+ u32 clock;
+ u32 i2c_id;
+};
+
+int loongson_i2c_init(struct loongson_device *ldev);
+
+#endif /* __LOONGSON_I2C_H__ */
--
2.25.1</pre></div>
</div><!--�-->
</div>
</body>
</html>