media: i2c: imx258: Add support for running on 2 CSI data lanes

Extends the driver to also support 2 data lanes.
Frame rates are obviously more restricted on 2 lanes, but some
hardware simply hasn't wired more up.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c
index 18183f2..6065667 100644 (file)
--- a/drivers/media/i2c/imx258.c
+++ b/drivers/media/i2c/imx258.c
@@ -86,13 +86,17 @@ struct imx258_reg_list {
        const struct imx258_reg *regs;
 };
 
+#define IMX258_LANE_CONFIGS    2
+#define IMX258_2_LANE_MODE     0
+#define IMX258_4_LANE_MODE     1
+
 /* Link frequency config */
 struct imx258_link_freq_config {
        u64 link_frequency;
        u32 pixels_per_line;
 
        /* PLL registers for this link frequency */
-       struct imx258_reg_list reg_list;
+       struct imx258_reg_list reg_list[IMX258_LANE_CONFIGS];
 };
 
 /* Mode : resolution and related config&values */
@@ -112,8 +116,30 @@ struct imx258_mode {
        struct imx258_reg_list reg_list;
 };
 
-/* 4208x3120 needs 1267Mbps/lane, 4 lanes */
-static const struct imx258_reg mipi_1267mbps_19_2mhz[] = {
+/* 4208x3120 needs 1267Mbps/lane, 4 lanes. Use that rate on 2 lanes as well */
+static const struct imx258_reg mipi_1267mbps_19_2mhz_2l[] = {
+       { 0x0136, 0x13 },
+       { 0x0137, 0x33 },
+       { 0x0301, 0x0A },
+       { 0x0303, 0x02 },
+       { 0x0305, 0x03 },
+       { 0x0306, 0x00 },
+       { 0x0307, 0xC6 },
+       { 0x0309, 0x0A },
+       { 0x030B, 0x01 },
+       { 0x030D, 0x02 },
+       { 0x030E, 0x00 },
+       { 0x030F, 0xD8 },
+       { 0x0310, 0x00 },
+
+       { 0x0114, 0x01 },
+       { 0x0820, 0x09 },
+       { 0x0821, 0xa6 },
+       { 0x0822, 0x66 },
+       { 0x0823, 0x66 },
+};
+
+static const struct imx258_reg mipi_1267mbps_19_2mhz_4l[] = {
        { 0x0136, 0x13 },
        { 0x0137, 0x33 },
        { 0x0301, 0x05 },
@@ -127,16 +153,18 @@ static const struct imx258_reg mipi_1267mbps_19_2mhz[] = {
        { 0x030E, 0x00 },
        { 0x030F, 0xD8 },
        { 0x0310, 0x00 },
+
+       { 0x0114, 0x03 },
        { 0x0820, 0x13 },
        { 0x0821, 0x4C },
        { 0x0822, 0xCC },
        { 0x0823, 0xCC },
 };
 
-static const struct imx258_reg mipi_1272mbps_24mhz[] = {
+static const struct imx258_reg mipi_1272mbps_24mhz_2l[] = {
        { 0x0136, 0x18 },
        { 0x0137, 0x00 },
-       { 0x0301, 0x05 },
+       { 0x0301, 0x0a },
        { 0x0303, 0x02 },
        { 0x0305, 0x04 },
        { 0x0306, 0x00 },
@@ -147,13 +175,59 @@ static const struct imx258_reg mipi_1272mbps_24mhz[] = {
        { 0x030E, 0x00 },
        { 0x030F, 0xD8 },
        { 0x0310, 0x00 },
+
+       { 0x0114, 0x01 },
        { 0x0820, 0x13 },
        { 0x0821, 0x4C },
        { 0x0822, 0xCC },
        { 0x0823, 0xCC },
 };
 
-static const struct imx258_reg mipi_640mbps_19_2mhz[] = {
+static const struct imx258_reg mipi_1272mbps_24mhz_4l[] = {
+       { 0x0136, 0x18 },
+       { 0x0137, 0x00 },
+       { 0x0301, 0x05 },
+       { 0x0303, 0x02 },
+       { 0x0305, 0x04 },
+       { 0x0306, 0x00 },
+       { 0x0307, 0xD4 },
+       { 0x0309, 0x0A },
+       { 0x030B, 0x01 },
+       { 0x030D, 0x02 },
+       { 0x030E, 0x00 },
+       { 0x030F, 0xD8 },
+       { 0x0310, 0x00 },
+
+       { 0x0114, 0x03 },
+       { 0x0820, 0x13 },
+       { 0x0821, 0xE0 },
+       { 0x0822, 0x00 },
+       { 0x0823, 0x00 },
+};
+
+static const struct imx258_reg mipi_640mbps_19_2mhz_2l[] = {
+       { 0x0136, 0x13 },
+       { 0x0137, 0x33 },
+       { 0x0301, 0x05 },
+       { 0x0303, 0x02 },
+       { 0x0305, 0x03 },
+       { 0x0306, 0x00 },
+       { 0x0307, 0x64 },
+       { 0x0309, 0x0A },
+       { 0x030B, 0x01 },
+       { 0x030D, 0x02 },
+       { 0x030E, 0x00 },
+       { 0x030F, 0xD8 },
+       { 0x0310, 0x00 },
+
+       { 0x0114, 0x01 },
+       { 0x0820, 0x05 },
+       { 0x0821, 0x00 },
+       { 0x0822, 0x00 },
+       { 0x0823, 0x00 },
+};
+
+static const struct imx258_reg mipi_640mbps_19_2mhz_4l[] = {
        { 0x0136, 0x13 },
        { 0x0137, 0x33 },
        { 0x0301, 0x05 },
@@ -167,13 +241,37 @@ static const struct imx258_reg mipi_640mbps_19_2mhz[] = {
        { 0x030E, 0x00 },
        { 0x030F, 0xD8 },
        { 0x0310, 0x00 },
+
+       { 0x0114, 0x03 },
+       { 0x0820, 0x0A },
+       { 0x0821, 0x00 },
+       { 0x0822, 0x00 },
+       { 0x0823, 0x00 },
+};
+
+static const struct imx258_reg mipi_642mbps_24mhz_2l[] = {
+       { 0x0136, 0x18 },
+       { 0x0137, 0x00 },
+       { 0x0301, 0x0A },
+       { 0x0303, 0x02 },
+       { 0x0305, 0x04 },
+       { 0x0306, 0x00 },
+       { 0x0307, 0x6B },
+       { 0x0309, 0x0A },
+       { 0x030B, 0x01 },
+       { 0x030D, 0x02 },
+       { 0x030E, 0x00 },
+       { 0x030F, 0xD8 },
+       { 0x0310, 0x00 },
+
+       { 0x0114, 0x01 },
        { 0x0820, 0x0A },
        { 0x0821, 0x00 },
        { 0x0822, 0x00 },
        { 0x0823, 0x00 },
 };
 
-static const struct imx258_reg mipi_642mbps_24mhz[] = {
+static const struct imx258_reg mipi_642mbps_24mhz_4l[] = {
        { 0x0136, 0x18 },
        { 0x0137, 0x00 },
        { 0x0301, 0x05 },
@@ -187,6 +285,8 @@ static const struct imx258_reg mipi_642mbps_24mhz[] = {
        { 0x030E, 0x00 },
        { 0x030F, 0xD8 },
        { 0x0310, 0x00 },
+
+       { 0x0114, 0x03 },
        { 0x0820, 0x0A },
        { 0x0821, 0x00 },
        { 0x0822, 0x00 },
@@ -241,7 +341,6 @@ static const struct imx258_reg mode_4208x3120_regs[] = {
        { 0x5F05, 0xED },
        { 0x0112, 0x0A },
        { 0x0113, 0x0A },
-       { 0x0114, 0x03 },
        { 0x0342, 0x14 },
        { 0x0343, 0xE8 },
        { 0x0344, 0x00 },
@@ -354,7 +453,6 @@ static const struct imx258_reg mode_2104_1560_regs[] = {
        { 0x5F05, 0xED },
        { 0x0112, 0x0A },
        { 0x0113, 0x0A },
-       { 0x0114, 0x03 },
        { 0x0342, 0x14 },
        { 0x0343, 0xE8 },
        { 0x0344, 0x00 },
@@ -467,7 +565,6 @@ static const struct imx258_reg mode_1048_780_regs[] = {
        { 0x5F05, 0xED },
        { 0x0112, 0x0A },
        { 0x0113, 0x0A },
-       { 0x0114, 0x03 },
        { 0x0342, 0x14 },
        { 0x0343, 0xE8 },
        { 0x0344, 0x00 },
@@ -557,11 +654,13 @@ enum {
 
 /*
  * pixel_rate = link_freq * data-rate * nr_of_lanes / bits_per_sample
- * data rate => double data rate; number of lanes => 4; bits per pixel => 10
+ * data rate => double data rate;
+ * number of lanes => (configurable 2 or 4);
+ * bits per pixel => 10
  */
-static u64 link_freq_to_pixel_rate(u64 f)
+static u64 link_freq_to_pixel_rate(u64 f, unsigned int nlanes)
 {
-       f *= 2 * 4;
+       f *= 2 * nlanes;
        do_div(f, 10);
 
        return f;
@@ -591,15 +690,27 @@ static const struct imx258_link_freq_config link_freq_configs_19_2[] = {
        [IMX258_LINK_FREQ_1267MBPS] = {
                .pixels_per_line = IMX258_PPL_DEFAULT,
                .reg_list = {
-                       .num_of_regs = ARRAY_SIZE(mipi_1267mbps_19_2mhz),
-                       .regs = mipi_1267mbps_19_2mhz,
+                       [IMX258_2_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_1267mbps_19_2mhz_2l),
+                               .regs = mipi_1267mbps_19_2mhz_2l,
+                       },
+                       [IMX258_4_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_1267mbps_19_2mhz_4l),
+                               .regs = mipi_1267mbps_19_2mhz_4l,
+                       },
                }
        },
        [IMX258_LINK_FREQ_640MBPS] = {
                .pixels_per_line = IMX258_PPL_DEFAULT,
                .reg_list = {
-                       .num_of_regs = ARRAY_SIZE(mipi_640mbps_19_2mhz),
-                       .regs = mipi_640mbps_19_2mhz,
+                       [IMX258_2_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_640mbps_19_2mhz_2l),
+                               .regs = mipi_640mbps_19_2mhz_2l,
+                       },
+                       [IMX258_4_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_640mbps_19_2mhz_4l),
+                               .regs = mipi_640mbps_19_2mhz_4l,
+                       },
                }
        },
 };
@@ -608,15 +719,27 @@ static const struct imx258_link_freq_config link_freq_configs_24[] = {
        [IMX258_LINK_FREQ_1267MBPS] = {
                .pixels_per_line = IMX258_PPL_DEFAULT,
                .reg_list = {
-                       .num_of_regs = ARRAY_SIZE(mipi_1272mbps_24mhz),
-                       .regs = mipi_1272mbps_24mhz,
+                       [IMX258_2_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_1272mbps_24mhz_2l),
+                               .regs = mipi_1272mbps_24mhz_2l,
+                       },
+                       [IMX258_4_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_1272mbps_24mhz_4l),
+                               .regs = mipi_1272mbps_24mhz_4l,
+                       },
                }
        },
        [IMX258_LINK_FREQ_640MBPS] = {
                .pixels_per_line = IMX258_PPL_DEFAULT,
                .reg_list = {
-                       .num_of_regs = ARRAY_SIZE(mipi_642mbps_24mhz),
-                       .regs = mipi_642mbps_24mhz,
+                       [IMX258_2_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_642mbps_24mhz_2l),
+                               .regs = mipi_642mbps_24mhz_2l,
+                       },
+                       [IMX258_4_LANE_MODE] = {
+                               .num_of_regs = ARRAY_SIZE(mipi_642mbps_24mhz_4l),
+                               .regs = mipi_642mbps_24mhz_4l,
+                       },
                }
        },
 };
@@ -675,6 +798,7 @@ struct imx258 {
 
        const struct imx258_link_freq_config *link_freq_configs;
        const s64 *link_freq_menu_items;
+       unsigned int nlanes;
 
        /*
         * Mutex for serialized access:
@@ -984,7 +1108,7 @@ static int imx258_set_pad_format(struct v4l2_subdev *sd,
                __v4l2_ctrl_s_ctrl(imx258->link_freq, mode->link_freq_index);
 
                link_freq = imx258->link_freq_menu_items[mode->link_freq_index];
-               pixel_rate = link_freq_to_pixel_rate(link_freq);
+               pixel_rate = link_freq_to_pixel_rate(link_freq, imx258->nlanes);
                __v4l2_ctrl_s_ctrl_int64(imx258->pixel_rate, pixel_rate);
                /* Update limits and set FPS to default */
                vblank_def = imx258->cur_mode->vts_def -
@@ -1013,11 +1137,13 @@ static int imx258_start_streaming(struct imx258 *imx258)
 {
        struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
        const struct imx258_reg_list *reg_list;
+       const struct imx258_link_freq_config *link_freq_cfg;
        int ret, link_freq_index;
 
        /* Setup PLL */
        link_freq_index = imx258->cur_mode->link_freq_index;
-       reg_list = &imx258->link_freq_configs[link_freq_index].reg_list;
+       link_freq_cfg = &imx258->link_freq_configs[link_freq_index];
+       reg_list = &link_freq_cfg->reg_list[imx258->nlanes == 2 ? 0 : 1];
        ret = imx258_write_regs(imx258, reg_list->regs, reg_list->num_of_regs);
        if (ret) {
                dev_err(&client->dev, "%s failed to set plls\n", __func__);
@@ -1264,9 +1390,11 @@ static int imx258_init_controls(struct imx258 *imx258)
                vflip->flags |= V4L2_CTRL_FLAG_READ_ONLY;
 
        pixel_rate_max =
-               link_freq_to_pixel_rate(imx258->link_freq_menu_items[0]);
+               link_freq_to_pixel_rate(imx258->link_freq_menu_items[0],
+                                       imx258->nlanes);
        pixel_rate_min =
-               link_freq_to_pixel_rate(imx258->link_freq_menu_items[1]);
+               link_freq_to_pixel_rate(imx258->link_freq_menu_items[1],
+                                       imx258->nlanes);
        /* By default, PIXEL_RATE is read only */
        imx258->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, &imx258_ctrl_ops,
                                V4L2_CID_PIXEL_RATE,
@@ -1364,6 +1492,10 @@ static int imx258_get_regulators(struct imx258 *imx258,
 static int imx258_probe(struct i2c_client *client)
 {
        struct imx258 *imx258;
+       struct fwnode_handle *endpoint;
+       struct v4l2_fwnode_endpoint ep = {
+               .bus_type = V4L2_MBUS_CSI2_DPHY
+       };
        int ret;
        u32 val = 0;
 
@@ -1406,13 +1538,38 @@ static int imx258_probe(struct i2c_client *client)
                return -EINVAL;
        }
 
+       endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);
+       if (!endpoint) {
+               dev_err(&client->dev, "Endpoint node not found\n");
+               return -EINVAL;
+       }
+
+       ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &ep);
+       fwnode_handle_put(endpoint);
+       if (ret == -ENXIO) {
+               dev_err(&client->dev, "Unsupported bus type, should be CSI2\n");
+               goto error_endpoint_poweron;
+       } else if (ret) {
+               dev_err(&client->dev, "Parsing endpoint node failed\n");
+               goto error_endpoint_poweron;
+       }
+
+       /* Get number of data lanes */
+       imx258->nlanes = ep.bus.mipi_csi2.num_data_lanes;
+       if (imx258->nlanes != 2 && imx258->nlanes != 4) {
+               dev_err(&client->dev, "Invalid data lanes: %u\n",
+                       imx258->nlanes);
+               ret = -EINVAL;
+               goto error_endpoint_poweron;
+       }
+
        /* Initialize subdev */
        v4l2_i2c_subdev_init(&imx258->sd, client, &imx258_subdev_ops);
 
        /* Will be powered off via pm_runtime_idle */
        ret = imx258_power_on(&client->dev);
        if (ret)
-               return ret;
+               goto error_endpoint_poweron;
 
        /* Check module identity */
        ret = imx258_identify_module(imx258);
@@ -1457,6 +1614,9 @@ error_handler_free:
 error_identify:
        imx258_power_off(&client->dev);
 
+error_endpoint_poweron:
+       v4l2_fwnode_endpoint_free(&ep);
+
        return ret;
 }