Re: [PATCH 1/5] media: i2c: imx290: Add support for 2 data lanes

Sakari Ailus
2019-12-03T08:46:22Z

Hi Manivannan,

Thanks for the patchset.

On Sat, Nov 30, 2019 at 12:35:37AM +0530, Manivannan Sadhasivam wrote:
> The IMX290 sensor can output frames with 2/4 CSI2 data lanes. This commit
> adds support for 2 lane mode in addition to the 4 lane and also
> configuring the data lane settings in the driver based on system
> configuration.
>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
> drivers/media/i2c/imx290.c | 130 ++++++++++++++++++++++++++++++++++---
> 1 file changed, 121 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
> index f7678e5a5d87..1d49910937fb 100644
> --- a/drivers/media/i2c/imx290.c
> +++ b/drivers/media/i2c/imx290.c
> @@ -25,7 +25,18 @@
> #define IMX290_STANDBY 0x3000
> #define IMX290_REGHOLD 0x3001
> #define IMX290_XMSTA 0x3002
> +#define IMX290_FR_FDG_SEL 0x3009
> #define IMX290_GAIN 0x3014
> +#define IMX290_HMAX_LOW 0x301c
> +#define IMX290_HMAX_HIGH 0x301d
> +#define IMX290_PHY_LANE_NUM 0x3407
> +#define IMX290_CSI_LANE_MODE 0x3443
> +
> +/* HMAX fields */
> +#define IMX290_HMAX_2_1920 0x1130
> +#define IMX290_HMAX_4_1920 0x0898
> +#define IMX290_HMAX_2_720 0x19C8
> +#define IMX290_HMAX_4_720 0x0CE4
>
> #define IMX290_DEFAULT_LINK_FREQ 445500000
>
> @@ -56,6 +67,7 @@ struct imx290 {
> struct device *dev;
> struct clk *xclk;
> struct regmap *regmap;
> + int nlanes;

You're using u8 for another small (unsigned) integer later. How about u8
here?

>
> struct v4l2_subdev sd;
> struct v4l2_fwnode_endpoint ep;
> @@ -89,14 +101,11 @@ static const struct regmap_config imx290_regmap_config = {
>
> static const struct imx290_regval imx290_global_init_settings[] = {
> { 0x3007, 0x00 },
> - { 0x3009, 0x00 },
> { 0x3018, 0x65 },
> { 0x3019, 0x04 },
> { 0x301a, 0x00 },
> - { 0x3443, 0x03 },
> { 0x3444, 0x20 },
> { 0x3445, 0x25 },
> - { 0x3407, 0x03 },
> { 0x303a, 0x0c },
> { 0x3040, 0x00 },
> { 0x3041, 0x00 },
> @@ -169,7 +178,6 @@ static const struct imx290_regval imx290_1080p_settings[] = {
> { 0x3164, 0x1a },
> { 0x3480, 0x49 },
> /* data rate settings */
> - { 0x3009, 0x01 },
> { 0x3405, 0x10 },
> { 0x3446, 0x57 },
> { 0x3447, 0x00 },
> @@ -187,8 +195,6 @@ static const struct imx290_regval imx290_1080p_settings[] = {
> { 0x3453, 0x00 },
> { 0x3454, 0x17 },
> { 0x3455, 0x00 },
> - { 0x301c, 0x98 },
> - { 0x301d, 0x08 },
> };
>
> static const struct imx290_regval imx290_720p_settings[] = {
> @@ -210,7 +216,6 @@ static const struct imx290_regval imx290_720p_settings[] = {
> { 0x3164, 0x1a },
> { 0x3480, 0x49 },
> /* data rate settings */
> - { 0x3009, 0x01 },
> { 0x3405, 0x10 },
> { 0x3446, 0x4f },
> { 0x3447, 0x00 },
> @@ -228,8 +233,6 @@ static const struct imx290_regval imx290_720p_settings[] = {
> { 0x3453, 0x00 },
> { 0x3454, 0x17 },
> { 0x3455, 0x00 },
> - { 0x301c, 0xe4 },
> - { 0x301d, 0x0c },
> };
>
> static const struct imx290_regval imx290_10bit_settings[] = {
> @@ -522,6 +525,25 @@ static int imx290_write_current_format(struct imx290 *imx290,
> return 0;
> }
>
> +static int imx290_set_hmax(struct imx290 *imx290, u32 val)
> +{
> + int ret;
> +
> + ret = imx290_write_reg(imx290, IMX290_HMAX_LOW, (val & 0xff));
> + if (ret) {
> + dev_err(imx290->dev, "Error setting HMAX register\n");
> + return ret;
> + }
> +
> + ret = imx290_write_reg(imx290, IMX290_HMAX_HIGH, ((val >> 8) & 0xff));
> + if (ret) {
> + dev_err(imx290->dev, "Error setting HMAX register\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> /* Start streaming */
> static int imx290_start_streaming(struct imx290 *imx290)
> {
> @@ -551,6 +573,40 @@ static int imx290_start_streaming(struct imx290 *imx290)
> return ret;
> }
>
> + switch (imx290->nlanes) {
> + case 2:
> + if (imx290->current_mode->width == 1920) {
> + ret = imx290_set_hmax(imx290, IMX290_HMAX_2_1920);
> + if (ret < 0)
> + return ret;
> + } else {
> + ret = imx290_set_hmax(imx290, IMX290_HMAX_2_720);
> + if (ret < 0)
> + return ret;
> + }
> +
> + break;
> + case 4:
> + if (imx290->current_mode->width == 1920) {
> + ret = imx290_set_hmax(imx290, IMX290_HMAX_4_1920);
> + if (ret < 0)
> + return ret;
> + } else {
> + ret = imx290_set_hmax(imx290, IMX290_HMAX_4_720);
> + if (ret < 0)
> + return ret;
> + }
> +
> + break;
> + default:
> + /*
> + * We should never hit this since the data lane count is
> + * validated in probe itself
> + */
> + dev_err(imx290->dev, "Lane configuration not supported\n");
> + return -EINVAL;
> + }
> +
> /* Apply customized values from user */
> ret = v4l2_ctrl_handler_setup(imx290->sd.ctrl_handler);
> if (ret) {
> @@ -607,6 +663,49 @@ static int imx290_get_regulators(struct device *dev, struct imx290 *imx290)
> imx290->supplies);
> }
>
> +static int imx290_set_data_lanes(struct imx290 *imx290)
> +{
> + int ret = 0, laneval, frsel;
> +
> + switch (imx290->nlanes) {
> + case 2:
> + laneval = 0x01;
> + frsel = 0x02;
> + break;
> + case 4:
> + laneval = 0x03;
> + frsel = 0x01;
> + break;
> + default:
> + /*
> + * We should never hit this since the data lane count is
> + * validated in probe itself
> + */
> + dev_err(imx290->dev, "Lane configuration not supported\n");
> + ret = -EINVAL;
> + goto exit;
> + }
> +
> + ret = imx290_write_reg(imx290, IMX290_PHY_LANE_NUM, laneval);
> + if (ret) {
> + dev_err(imx290->dev, "Error setting Physical Lane number register\n");
> + goto exit;
> + }
> +
> + ret = imx290_write_reg(imx290, IMX290_CSI_LANE_MODE, laneval);
> + if (ret) {
> + dev_err(imx290->dev, "Error setting CSI Lane mode register\n");
> + goto exit;
> + }
> +
> + ret = imx290_write_reg(imx290, IMX290_FR_FDG_SEL, frsel);
> + if (ret)
> + dev_err(imx290->dev, "Error setting FR/FDG SEL register\n");
> +
> +exit:
> + return ret;
> +}
> +
> static int imx290_power_on(struct device *dev)
> {
> struct i2c_client *client = to_i2c_client(dev);
> @@ -703,6 +802,16 @@ static int imx290_probe(struct i2c_client *client)
> goto free_err;
> }
>
> + /* Get number of data lanes */
> + imx290->nlanes = imx290->ep.bus.mipi_csi2.num_data_lanes;
> + if (imx290->nlanes != 2 && imx290->nlanes != 4) {
> + dev_err(dev, "Invalid data lanes: %d\n", imx290->nlanes);
> + ret = -EINVAL;
> + goto free_err;
> + }
> +
> + dev_dbg(dev, "Using %u data lanes\n", imx290->nlanes);
> +
> if (!imx290->ep.nr_of_link_frequencies) {
> dev_err(dev, "link-frequency property not found in DT\n");
> ret = -EINVAL;
> @@ -822,6 +931,9 @@ static int imx290_probe(struct i2c_client *client)
> goto free_entity;
> }
>
> + /* Set data lane count */
> + imx290_set_data_lanes(imx290);

The sensor is likely (but not necessarily) about to be powered off here.
Wouldn't this also belong to be put to the power on sequence?

> +
> pm_runtime_set_active(dev);
> pm_runtime_enable(dev);
> pm_runtime_idle(dev);

--
Regards,

Sakari Ailus