[PATCH 2/2] media: gc2145: implement basic dvp bus support

From: Andrey Skvortsov
Date: Sat Feb 17 2024 - 17:04:33 EST


Tested on PinePhone with libcamera-based GNOME screenshot.

Signed-off-by: Andrey Skvortsov <andrej.skvortzov@xxxxxxxxx>
---
drivers/media/i2c/gc2145.c | 117 ++++++++++++++++++++++++++++---------
1 file changed, 90 insertions(+), 27 deletions(-)

diff --git a/drivers/media/i2c/gc2145.c b/drivers/media/i2c/gc2145.c
index bef7b0e056a8..9a70b8d504e1 100644
--- a/drivers/media/i2c/gc2145.c
+++ b/drivers/media/i2c/gc2145.c
@@ -39,6 +39,10 @@
#define GC2145_REG_ANALOG_MODE1 CCI_REG8(0x17)
#define GC2145_REG_OUTPUT_FMT CCI_REG8(0x84)
#define GC2145_REG_SYNC_MODE CCI_REG8(0x86)
+#define GC2145_SYNC_MODE_VSYNC_POL BIT(0)
+#define GC2145_SYNC_MODE_HSYNC_POL BIT(1)
+#define GC2145_SYNC_MODE_OPCLK_POL BIT(2)
+#define GC2145_SYNC_MODE_OPCLK_GATE BIT(3)
#define GC2145_SYNC_MODE_COL_SWITCH BIT(4)
#define GC2145_SYNC_MODE_ROW_SWITCH BIT(5)
#define GC2145_REG_BYPASS_MODE CCI_REG8(0x89)
@@ -53,6 +57,12 @@
#define GC2145_REG_GLOBAL_GAIN CCI_REG8(0xb0)
#define GC2145_REG_CHIP_ID CCI_REG16(0xf0)
#define GC2145_REG_PAD_IO CCI_REG8(0xf2)
+#define GC2145_REG_PLL_MODE1 CCI_REG8(0xf7)
+#define GC2145_REG_PLL_MODE2 CCI_REG8(0xf8)
+#define GC2145_REG_CM_MODE CCI_REG8(0xf9)
+#define GC2145_REG_CLK_DIV_MODE CCI_REG8(0xfa)
+#define GC2145_REG_ANALOG_PWC CCI_REG8(0xfc)
+#define GC2145_REG_PAD_IO CCI_REG8(0xf2)
#define GC2145_REG_PAGE_SELECT CCI_REG8(0xfe)
/* Page 3 */
#define GC2145_REG_DPHY_ANALOG_MODE1 CCI_REG8(0x01)
@@ -598,6 +608,7 @@ struct gc2145 {
struct v4l2_subdev sd;
struct media_pad pad;

+ struct v4l2_fwnode_endpoint ep; /* the parsed DT endpoint info */
struct regmap *regmap;
struct clk *xclk;

@@ -612,6 +623,11 @@ struct gc2145 {
const struct gc2145_mode *mode;
};

+static inline bool gc2145_is_csi2(const struct gc2145 *gc2145)
+{
+ return gc2145->ep.bus_type == V4L2_MBUS_CSI2_DPHY;
+}
+
static inline struct gc2145 *to_gc2145(struct v4l2_subdev *_sd)
{
return container_of(_sd, struct gc2145, sd);
@@ -773,6 +789,38 @@ static int gc2145_set_pad_format(struct v4l2_subdev *sd,
return 0;
}

+static int gc2145_config_dvp_mode(struct gc2145 *gc2145,
+ const struct gc2145_format *gc2145_format)
+{
+ int ret = 0;
+ u64 sync_mode;
+ int flags;
+
+ flags = gc2145->ep.bus.parallel.flags;
+
+ ret = cci_read(gc2145->regmap, GC2145_REG_SYNC_MODE, &sync_mode, NULL);
+ if (ret)
+ return ret;
+
+ sync_mode &= ~(GC2145_SYNC_MODE_VSYNC_POL |
+ GC2145_SYNC_MODE_HSYNC_POL |
+ GC2145_SYNC_MODE_OPCLK_POL);
+
+ if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
+ sync_mode |= GC2145_SYNC_MODE_VSYNC_POL;
+
+ if (flags & V4L2_MBUS_HSYNC_ACTIVE_LOW)
+ sync_mode |= GC2145_SYNC_MODE_HSYNC_POL;
+
+ if (flags & V4L2_MBUS_PCLK_SAMPLE_FALLING)
+ sync_mode |= GC2145_SYNC_MODE_OPCLK_POL;
+
+ cci_write(gc2145->regmap, GC2145_REG_SYNC_MODE, sync_mode, &ret);
+ cci_write(gc2145->regmap, GC2145_REG_PAD_IO, 0x0f, &ret);
+
+ return ret;
+}
+
static const struct cci_reg_sequence gc2145_common_mipi_regs[] = {
{GC2145_REG_PAGE_SELECT, 0x03},
{GC2145_REG_DPHY_ANALOG_MODE1, GC2145_DPHY_MODE_PHY_CLK_EN |
@@ -895,10 +943,13 @@ static int gc2145_start_streaming(struct gc2145 *gc2145,
goto err_rpm_put;
}

- /* Perform MIPI specific configuration */
- ret = gc2145_config_mipi_mode(gc2145, gc2145_format);
+ /* Perform interface specific configuration */
+ if (gc2145_is_csi2(gc2145))
+ ret = gc2145_config_mipi_mode(gc2145, gc2145_format);
+ else
+ ret = gc2145_config_dvp_mode(gc2145, gc2145_format);
if (ret) {
- dev_err(&client->dev, "%s failed to write mipi conf\n",
+ dev_err(&client->dev, "%s failed to write interface conf\n",
__func__);
goto err_rpm_put;
}
@@ -924,6 +975,9 @@ static void gc2145_stop_streaming(struct gc2145 *gc2145)
GC2145_CSI2_MODE_EN | GC2145_CSI2_MODE_MIPI_EN, 0,
&ret);
cci_write(gc2145->regmap, GC2145_REG_PAGE_SELECT, 0x00, &ret);
+
+ /* Disable dvp streaming */
+ cci_write(gc2145->regmap, GC2145_REG_PAD_IO, 0x00, &ret);
if (ret)
dev_err(&client->dev, "%s failed to write regs\n", __func__);

@@ -1233,9 +1287,8 @@ static int gc2145_init_controls(struct gc2145 *gc2145)
static int gc2145_check_hwcfg(struct device *dev)
{
struct fwnode_handle *endpoint;
- struct v4l2_fwnode_endpoint ep_cfg = {
- .bus_type = V4L2_MBUS_CSI2_DPHY
- };
+ struct v4l2_subdev *sd = dev_get_drvdata(dev);
+ struct gc2145 *gc2145 = to_gc2145(sd);
int ret;

endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(dev), NULL);
@@ -1244,36 +1297,46 @@ static int gc2145_check_hwcfg(struct device *dev)
return -EINVAL;
}

- ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &ep_cfg);
+ ret = v4l2_fwnode_endpoint_parse(endpoint, &gc2145->ep);
fwnode_handle_put(endpoint);
if (ret)
return ret;

- /* Check the number of MIPI CSI2 data lanes */
- if (ep_cfg.bus.mipi_csi2.num_data_lanes != 2) {
- dev_err(dev, "only 2 data lanes are currently supported\n");
- ret = -EINVAL;
- goto out;
- }
+ switch (gc2145->ep.bus_type) {
+ case V4L2_MBUS_CSI2_DPHY:
+ /* Check the link frequency set in device tree */
+ if (!gc2145->ep.nr_of_link_frequencies) {
+ dev_err(dev, "link-frequencies property not found in DT\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Check the number of MIPI CSI2 data lanes */
+ if (gc2145->ep.bus.mipi_csi2.num_data_lanes != 2) {
+ dev_err(dev, "only 2 data lanes are currently supported\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (gc2145->ep.nr_of_link_frequencies != 3 ||
+ gc2145->ep.link_frequencies[0] != GC2145_640_480_LINKFREQ ||
+ gc2145->ep.link_frequencies[1] != GC2145_1280_720_LINKFREQ ||
+ gc2145->ep.link_frequencies[2] != GC2145_1600_1200_LINKFREQ) {
+ dev_err(dev, "Invalid link-frequencies provided\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ break;

- /* Check the link frequency set in device tree */
- if (!ep_cfg.nr_of_link_frequencies) {
- dev_err(dev, "link-frequency property not found in DT\n");
+ case V4L2_MBUS_PARALLEL:
+ break;
+ default:
+ dev_err(dev, "unsupported bus type %u\n",
+ gc2145->ep.bus_type);
ret = -EINVAL;
goto out;
}
-
- if (ep_cfg.nr_of_link_frequencies != 3 ||
- ep_cfg.link_frequencies[0] != GC2145_640_480_LINKFREQ ||
- ep_cfg.link_frequencies[1] != GC2145_1280_720_LINKFREQ ||
- ep_cfg.link_frequencies[2] != GC2145_1600_1200_LINKFREQ) {
- dev_err(dev, "Invalid link-frequencies provided\n");
- ret = -EINVAL;
- }
-
out:
- v4l2_fwnode_endpoint_free(&ep_cfg);
-
return ret;
}

--
2.43.0