[PATCH] media: i2c: imx334: add new link frequency configuration

From: shravan kumar

Date: Tue May 19 2026 - 07:17:40 EST


From: Shravan Chippa <shravan.chippa@xxxxxxxxxxxxx>

Add support for a new 222 MHz link frequency configuration to the
IMX334 driver and dynamically generate the supported modes array
based on the link frequencies specified in the DTS. When multiple
link frequencies support the same resolution, the driver selects
the first matching entry; therefore, the link frequency must be
explicitly defined in the DTS to avoid resolution conflicts.
The link frequency is a read‑only parameter and is automatically
set based on the selected resolution and DTS configuration.

Signed-off-by: Shravan Chippa <shravan.chippa@xxxxxxxxxxxxx>
---
drivers/media/i2c/imx334.c | 112 +++++++++++++++++++++++++++++++++++--
1 file changed, 106 insertions(+), 6 deletions(-)

diff --git a/drivers/media/i2c/imx334.c b/drivers/media/i2c/imx334.c
index 9654f9268056..336de9cd8ff2 100644
--- a/drivers/media/i2c/imx334.c
+++ b/drivers/media/i2c/imx334.c
@@ -109,6 +109,7 @@
/* CSI2 HW configuration */
#define IMX334_LINK_FREQ_891M 891000000
#define IMX334_LINK_FREQ_445M 445500000
+#define IMX334_LINK_FREQ_222M 222500000
#define IMX334_NUM_DATA_LANES 4

#define IMX334_REG_MIN 0x00
@@ -209,6 +210,8 @@ struct imx334 {
};
u32 vblank;
const struct imx334_mode *cur_mode;
+ const struct imx334_mode *new_supported_modes;
+ int new_modes_size;
unsigned long link_freq_bitmap;
u32 cur_code;
};
@@ -216,6 +219,7 @@ struct imx334 {
static const s64 link_freq[] = {
IMX334_LINK_FREQ_891M,
IMX334_LINK_FREQ_445M,
+ IMX334_LINK_FREQ_222M,
};

/* Sensor common mode registers values */
@@ -486,6 +490,45 @@ static const struct imx334_mode supported_modes[] = {
.num_of_regs = ARRAY_SIZE(mode_640x480_regs),
.regs = mode_640x480_regs,
},
+ }, {
+ .width = 1920,
+ .height = 1080,
+ .hblank = 2480,
+ .vblank = 1170,
+ .vblank_min = 45,
+ .vblank_max = 132840,
+ .pclk = 297000000,
+ .link_freq_idx = 2,
+ .reg_list = {
+ .num_of_regs = ARRAY_SIZE(mode_1920x1080_regs),
+ .regs = mode_1920x1080_regs,
+ },
+ }, {
+ .width = 1280,
+ .height = 720,
+ .hblank = 2480,
+ .vblank = 1170,
+ .vblank_min = 45,
+ .vblank_max = 132840,
+ .pclk = 297000000,
+ .link_freq_idx = 2,
+ .reg_list = {
+ .num_of_regs = ARRAY_SIZE(mode_1280x720_regs),
+ .regs = mode_1280x720_regs,
+ },
+ }, {
+ .width = 640,
+ .height = 480,
+ .hblank = 2480,
+ .vblank = 1170,
+ .vblank_min = 45,
+ .vblank_max = 132840,
+ .pclk = 297000000,
+ .link_freq_idx = 2,
+ .reg_list = {
+ .num_of_regs = ARRAY_SIZE(mode_640x480_regs),
+ .regs = mode_640x480_regs,
+ },
},
};

@@ -713,7 +756,7 @@ static int imx334_enum_frame_size(struct v4l2_subdev *sd,
struct imx334 *imx334 = to_imx334(sd);
u32 code;

- if (fsize->index >= ARRAY_SIZE(supported_modes))
+ if (fsize->index >= imx334->new_modes_size)
return -EINVAL;

code = imx334_get_format_code(imx334, fsize->code);
@@ -721,9 +764,9 @@ static int imx334_enum_frame_size(struct v4l2_subdev *sd,
if (fsize->code != code)
return -EINVAL;

- fsize->min_width = supported_modes[fsize->index].width;
+ fsize->min_width = imx334->new_supported_modes[fsize->index].width;
fsize->max_width = fsize->min_width;
- fsize->min_height = supported_modes[fsize->index].height;
+ fsize->min_height = imx334->new_supported_modes[fsize->index].height;
fsize->max_height = fsize->min_height;

return 0;
@@ -792,8 +835,8 @@ static int imx334_set_pad_format(struct v4l2_subdev *sd,
const struct imx334_mode *mode;
int ret = 0;

- mode = v4l2_find_nearest_size(supported_modes,
- ARRAY_SIZE(supported_modes),
+ mode = v4l2_find_nearest_size(imx334->new_supported_modes,
+ imx334->new_modes_size,
width, height,
fmt->format.width, fmt->format.height);

@@ -914,6 +957,9 @@ static int imx334_enable_streams(struct v4l2_subdev *sd,
goto err_rpm_put;
}

+ if (link_freq[imx334->cur_mode->link_freq_idx] == IMX334_LINK_FREQ_222M)
+ cci_write(imx334->cci, IMX334_REG_INCKSEL2, 0x0a, NULL);
+
/* Start streaming */
ret = cci_write(imx334->cci, IMX334_REG_MODE_SELECT,
IMX334_MODE_STREAMING, NULL);
@@ -979,6 +1025,55 @@ static int imx334_detect(struct imx334 *imx334)
return 0;
}

+/**
+ * imx334_update_supported_mode_array() - Search for the supported
+ * modes add them in the new list
+ * @imx334: pointer to imx334 device
+ *
+ * Return: 0 if successful, error code otherwise.
+ */
+static int imx334_update_supported_mode_array(struct imx334 *imx334)
+{
+ int i, j, size = 0;
+ struct imx334_mode *temp_ptr;
+
+ for (i = 0; i < ARRAY_SIZE(link_freq); i++) {
+ if (imx334->link_freq_bitmap & (1 << i)) {
+ for (j = 0; j < ARRAY_SIZE(supported_modes); j++) {
+ if (supported_modes[j].link_freq_idx == i)
+ size++;
+ }
+ }
+ }
+
+ if (!size)
+ return -EINVAL;
+
+ imx334->new_modes_size = size;
+
+ size = 0;
+
+ temp_ptr = devm_kmalloc(imx334->dev, imx334->new_modes_size * sizeof(struct imx334_mode),
+ GFP_KERNEL);
+ if (!temp_ptr)
+ return -ENOMEM;
+
+ for (i = 0; i < ARRAY_SIZE(link_freq); i++) {
+ if (imx334->link_freq_bitmap & (1 << i)) {
+ for (j = 0; j < ARRAY_SIZE(supported_modes); j++) {
+ if (supported_modes[j].link_freq_idx == i) {
+ temp_ptr[size] = supported_modes[j];
+ size++;
+ }
+ }
+ }
+ }
+
+ imx334->new_supported_modes = temp_ptr;
+
+ return 0;
+}
+
/**
* imx334_parse_hw_config() - Parse HW configuration and check if supported
* @imx334: pointer to imx334 device
@@ -1038,6 +1133,11 @@ static int imx334_parse_hw_config(struct imx334 *imx334)
link_freq, ARRAY_SIZE(link_freq),
&imx334->link_freq_bitmap);

+ if (ret)
+ goto done_endpoint_free;
+
+ ret = imx334_update_supported_mode_array(imx334);
+
done_endpoint_free:
v4l2_fwnode_endpoint_free(&bus_cfg);

@@ -1251,7 +1351,7 @@ static int imx334_probe(struct i2c_client *client)
}

/* Set default mode to max resolution */
- imx334->cur_mode = &supported_modes[__ffs(imx334->link_freq_bitmap)];
+ imx334->cur_mode = &imx334->new_supported_modes[__ffs(imx334->link_freq_bitmap)];
imx334->cur_code = imx334_mbus_codes[0];
imx334->vblank = imx334->cur_mode->vblank;

--
2.34.1