Re: [PATCH v3 19/25] media: i2c: imx258: Change register settings for variants of the sensor

Sakari Ailus
2024-04-03T16:18:58Z

Hi Luis, Dave,

On Wed, Apr 03, 2024 at 09:03:48AM -0600, git@luigi311.com wrote:
> From: Dave Stevenson <dave.stevenson@raspberrypi.com>
>
> Sony have advised that there are variants of the IMX258 sensor which
> require slightly different register configuration to the mainline
> imx258 driver defaults.
>
> There is no available run-time detection for the variant, so add
> configuration via the DT compatible string.
>
> The Vision Components imx258 module supports PDAF, so add the
> register differences for that variant
>
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Signed-off-by: Luis Garcia <git@luigi311.com>
> ---
> drivers/media/i2c/imx258.c | 48 ++++++++++++++++++++++++++++++++++----
> 1 file changed, 44 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c
> index 775d957c9b87..fa48da212037 100644
> --- a/drivers/media/i2c/imx258.c
> +++ b/drivers/media/i2c/imx258.c
> @@ -6,6 +6,7 @@
> #include <linux/delay.h>
> #include <linux/i2c.h>
> #include <linux/module.h>
> +#include <linux/of_device.h>
> #include <linux/pm_runtime.h>
> #include <linux/regulator/consumer.h>
> #include <media/v4l2-ctrls.h>
> @@ -321,8 +322,6 @@ static const struct imx258_reg mipi_642mbps_24mhz_4l[] = {
>
> static const struct imx258_reg mode_common_regs[] = {
> { 0x3051, 0x00 },
> - { 0x3052, 0x00 },
> - { 0x4E21, 0x14 },
> { 0x6B11, 0xCF },
> { 0x7FF0, 0x08 },
> { 0x7FF1, 0x0F },
> @@ -345,7 +344,6 @@ static const struct imx258_reg mode_common_regs[] = {
> { 0x7FA8, 0x03 },
> { 0x7FA9, 0xFE },
> { 0x7B24, 0x81 },
> - { 0x7B25, 0x00 },
> { 0x6564, 0x07 },
> { 0x6B0D, 0x41 },
> { 0x653D, 0x04 },
> @@ -460,6 +458,33 @@ static const struct imx258_reg mode_1048_780_regs[] = {
> { 0x034F, 0x0C },
> };
>
> +struct imx258_variant_cfg {
> + const struct imx258_reg *regs;
> + unsigned int num_regs;
> +};
> +
> +static const struct imx258_reg imx258_cfg_regs[] = {
> + { 0x3052, 0x00 },
> + { 0x4E21, 0x14 },
> + { 0x7B25, 0x00 },
> +};
> +
> +static const struct imx258_variant_cfg imx258_cfg = {
> + .regs = imx258_cfg_regs,
> + .num_regs = ARRAY_SIZE(imx258_cfg_regs),
> +};
> +
> +static const struct imx258_reg imx258_pdaf_cfg_regs[] = {
> + { 0x3052, 0x01 },
> + { 0x4E21, 0x10 },
> + { 0x7B25, 0x01 },
> +};
> +
> +static const struct imx258_variant_cfg imx258_pdaf_cfg = {
> + .regs = imx258_pdaf_cfg_regs,
> + .num_regs = ARRAY_SIZE(imx258_pdaf_cfg_regs),
> +};
> +
> static const char * const imx258_test_pattern_menu[] = {
> "Disabled",
> "Solid Colour",
> @@ -637,6 +662,8 @@ struct imx258 {
> struct v4l2_subdev sd;
> struct media_pad pad;
>
> + const struct imx258_variant_cfg *variant_cfg;
> +
> struct v4l2_ctrl_handler ctrl_handler;
> /* V4L2 Controls */
> struct v4l2_ctrl *link_freq;
> @@ -1104,6 +1131,14 @@ static int imx258_start_streaming(struct imx258 *imx258)
> return ret;
> }
>
> + ret = imx258_write_regs(imx258, imx258->variant_cfg->regs,
> + imx258->variant_cfg->num_regs);
> + if (ret) {
> + dev_err(&client->dev, "%s failed to set variant config\n",
> + __func__);
> + return ret;
> + }
> +
> ret = imx258_write_reg(imx258, IMX258_CLK_BLANK_STOP,
> IMX258_REG_VALUE_08BIT,
> imx258->csi2_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK ?
> @@ -1492,6 +1527,10 @@ static int imx258_probe(struct i2c_client *client)
>
> imx258->csi2_flags = ep.bus.mipi_csi2.flags;
>
> + imx258->variant_cfg = of_device_get_match_data(&client->dev);

You'll also need to keep this working for ACPI based systems. I.e. in
practice remove "of_" prefix here and add the non-PDAF variant data to the
relevant ACPI ID list.

> + if (!imx258->variant_cfg)
> + imx258->variant_cfg = &imx258_cfg;
> +
> /* Initialize subdev */
> v4l2_i2c_subdev_init(&imx258->sd, client, &imx258_subdev_ops);
>
> @@ -1579,7 +1618,8 @@ MODULE_DEVICE_TABLE(acpi, imx258_acpi_ids);
> #endif
>
> static const struct of_device_id imx258_dt_ids[] = {
> - { .compatible = "sony,imx258" },
> + { .compatible = "sony,imx258", .data = &imx258_cfg },
> + { .compatible = "sony,imx258-pdaf", .data = &imx258_pdaf_cfg },
> { /* sentinel */ }
> };
> MODULE_DEVICE_TABLE(of, imx258_dt_ids);

--
Kind regards,

Sakari Ailus