Hi Andy,
Thanks for the patch. Let me post some comments inline.
On Fri, Mar 2, 2018 at 11:55 PM, Andy Yeh <andy.yeh@xxxxxxxxx> wrote:
> Add a V4L2 sub-device driver for the Sony IMX258 image sensor.
> This is a camera sensor using the I2C bus for control and the
> CSI-2 bus for data.
>
> Signed-off-by: Jason Chen <jasonx.z.chen@xxxxxxxxx>
> Signed-off-by: Alan Chiang <alanx.chiang@xxxxxxxxx>
> ---
> since v2:
> -- Update the streaming function to remove SW_STANDBY in the beginning.
> -- Adjust the delay time from 1ms to 12ms before set stream-on register.
> since v3:
> -- fix the sd.entity to make code be compiled on the mainline kernel.
> since v4:
> -- Enabled AG, DG, and Exposure time control correctly.
> since v5:
> -- Sensor vendor provided a new setting to fix different CLK issue
> -- Add one more resolution for 1048x780, used for VGA streaming
>
> MAINTAINERS | 7 +
> drivers/media/i2c/Kconfig | 11 +
> drivers/media/i2c/Makefile | 1 +
> drivers/media/i2c/imx258.c | 1341 ++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 1360 insertions(+)
> create mode 100644 drivers/media/i2c/imx258.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a339bb5..9f75510 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -12646,6 +12646,13 @@ S: Maintained
> F: drivers/ssb/
> F: include/linux/ssb/
>
> +SONY IMX258 SENSOR DRIVER
> +M: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> +L: linux-media@xxxxxxxxxxxxxxx
> +T: git git://linuxtv.org/media_tree.git
> +S: Maintained
> +F: drivers/media/i2c/imx258.c
> +
> SONY IMX274 SENSOR DRIVER
> M: Leon Luo <leonl@xxxxxxxxxxxxxxxxxx>
> L: linux-media@xxxxxxxxxxxxxxx
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index fd01842..bcd4bf1 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -565,6 +565,17 @@ config VIDEO_APTINA_PLL
> config VIDEO_SMIAPP_PLL
> tristate
>
> +config VIDEO_IMX258
> + tristate "Sony IMX258 sensor support"
> + depends on I2C && VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
> + depends on MEDIA_CAMERA_SUPPORT
> + ---help---
> + This is a Video4Linux2 sensor-level driver for the Sony
> + IMX258 camera.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called imx258.
> +
> config VIDEO_IMX274
> tristate "Sony IMX274 sensor support"
> depends on I2C && VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index 1b62639..4bf7d00 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -94,6 +94,7 @@ obj-$(CONFIG_VIDEO_IR_I2C) += ir-kbd-i2c.o
> obj-$(CONFIG_VIDEO_ML86V7667) += ml86v7667.o
> obj-$(CONFIG_VIDEO_OV2659) += ov2659.o
> obj-$(CONFIG_VIDEO_TC358743) += tc358743.o
> +obj-$(CONFIG_VIDEO_IMX258) += imx258.o
> obj-$(CONFIG_VIDEO_IMX274) += imx274.o
>
> obj-$(CONFIG_SDR_MAX2175) += max2175.o
> diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c
> new file mode 100644
> index 0000000..0418edd
> --- /dev/null
> +++ b/drivers/media/i2c/imx258.c
> @@ -0,0 +1,1341 @@
> +// Copyright (C) 2018 Intel Corporation
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +
> +#define IMX258_REG_VALUE_08BIT 1
> +#define IMX258_REG_VALUE_16BIT 2
> +#define IMX258_REG_VALUE_24BIT 3
Is there any need for these macros? Respective functions could just
take the number of bytes as the argument directly.
> +
> +#define IMX258_REG_MODE_SELECT 0x0100
> +#define IMX258_MODE_STANDBY 0x00
> +#define IMX258_MODE_STREAMING 0x01
> +
> +/* Chip ID */
> +#define IMX258_REG_CHIP_ID 0x0016
> +#define IMX258_CHIP_ID 0x0258
> +
> +/* V_TIMING internal */
> +#define IMX258_REG_VTS 0x0340
> +#define IMX258_VTS_30FPS 0x0c98
> +#define IMX258_VTS_MAX 0xffff
> +
> +/*Frame Length Line*/
> +#define IMX258_FLL_MIN 0x08a6
> +#define IMX258_FLL_MAX 0xffff
> +#define IMX258_FLL_STEP 1
> +#define IMX258_FLL_DEFAULT 0x0c98
> +
> +/* HBLANK control - read only */
> +#define IMX258_PPL_650MHZ 5352
> +#define IMX258_PPL_325MHZ 2676
> +
> +/* Exposure control */
> +#define IMX258_REG_EXPOSURE 0x0202
> +#define IMX258_EXPOSURE_MIN 4
> +#define IMX258_EXPOSURE_STEP 1
> +#define IMX258_EXPOSURE_DEFAULT 0x640
> +#define IMX258_EXPOSURE_MAX 65535
> +
> +/* Analog gain control */
> +#define IMX258_REG_ANALOG_GAIN 0x0204
> +#define IMX258_ANA_GAIN_MIN 0
> +#define IMX258_ANA_GAIN_MAX 0x1fff
> +#define IMX258_ANA_GAIN_STEP 1
> +#define IMX258_ANA_GAIN_DEFAULT 0x0
> +
> +/* Digital gain control */
> +#define IMX258_REG_GR_DIGITAL_GAIN 0x020e
> +#define IMX258_REG_R_DIGITAL_GAIN 0x0210
> +#define IMX258_REG_B_DIGITAL_GAIN 0x0212
> +#define IMX258_REG_GB_DIGITAL_GAIN 0x0214
> +#define IMX258_DGTL_GAIN_MIN 0
> +#define IMX258_DGTL_GAIN_MAX 4096 /* Max = 0xFFF */
> +#define IMX258_DGTL_GAIN_DEFAULT 1024
> +#define IMX258_DGTL_GAIN_STEP 1
> +
> +/* Orientation */
> +#define REG_MIRROR_FLIP_CONTROL 0x0101
> +#define REG_CONFIG_MIRROR_FLIP 0x03
> +
> +struct imx258_reg {
> + u16 address;
> + u8 val;
> +};
> +
> +struct imx258_reg_list {
> + u32 num_of_regs;
> + const struct imx258_reg *regs;
> +};
> +
> +/* Link frequency config */
> +struct imx258_link_freq_config {
> + u32 pixels_per_line;
> +
> + /* PLL registers for this link frequency */
> + struct imx258_reg_list reg_list;
> +};
> +
> +/* Mode : resolution and related config&values */
> +struct imx258_mode {
> + /* Frame width */
> + u32 width;
> + /* Frame height */
> + u32 height;
> +
> + /* V-timing */
> + u32 vts_def;
> + u32 vts_min;
> +
> + /* Index of Link frequency config to be used */
> + u32 link_freq_index;
> + /* Default register values */
> + struct imx258_reg_list reg_list;
> +};
> +
> +/* 4208x3118 needs 1300Mbps/lane, 4 lanes */
> +static const struct imx258_reg mipi_data_rate_1300mbps[] = {
> + {0x0301, 0x05},
CodingStyle: Spaces inside the braces and lowercase hex, e.g.
{ 0x1234, 0xabcd },
[snip]
> + {0x951B, 0x50},
> + {0x3030, 0x00},
> + {0x3032, 0x00},
> + {0x0220, 0x00},
> +};
nit: Blank line would be nice here.
> +static const char * const imx258_test_pattern_menu[] = {
> + "Disabled",
> + "Vertical Color Bar Type 1",
> + "Vertical Color Bar Type 2",
> + "Vertical Color Bar Type 3",
> + "Vertical Color Bar Type 4"
> +};
> +
> +/* Configurations for supported link frequencies */
> +#define IMX258_LINK_FREQ_650MHZ 649600000ULL
> +#define IMX258_LINK_FREQ_325MHZ 324800000ULL
> +
> +/*
> + * 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
> + */
> +static u64 link_freq_to_pixel_rate(u64 f)
> +{
> + f *= 2 * 4;
> + do_div(f, 10);
> +
> + return f;
> +}
> +
> +/* Menu items for LINK_FREQ V4L2 control */
> +static const s64 link_freq_menu_items[] = {
> + IMX258_LINK_FREQ_650MHZ,
> + IMX258_LINK_FREQ_325MHZ,
> +};
> +
> +/* Link frequency configs */
> +static const struct imx258_link_freq_config link_freq_configs[] = {
> + {
> + .pixels_per_line = IMX258_PPL_650MHZ,
> + .reg_list = {
> + .num_of_regs = ARRAY_SIZE(mipi_data_rate_1300mbps),
> + .regs = mipi_data_rate_1300mbps,
> + }
> + },
> + {
> + .pixels_per_line = IMX258_PPL_325MHZ,
> + .reg_list = {
> + .num_of_regs = ARRAY_SIZE(mipi_data_rate_650mbps),
> + .regs = mipi_data_rate_650mbps,
> + }
> + },
Could you define an enum for the entries here nd use explicit indexing? e.g.
enum {
IMX258_LINK_FREQ_1300MBPS,
IMX258_LINK_FREQ_650MBPS,
};
static const struct imx258_link_freq_config link_freq_configs[] = {
[IMX258_LINK_FREQ_1300MBPS] = { ... },
[IMX258_LINK_FREQ_650MBPS] = { ... },
};
and then... (See below.)
> +};
> +
> +/* Mode configs */
> +static const struct imx258_mode supported_modes[] = {
> + {
> + .width = 4208,
> + .height = 3118,
> + .vts_def = IMX258_VTS_30FPS,
> + .vts_min = IMX258_VTS_30FPS,
> + .reg_list = {
> + .num_of_regs = ARRAY_SIZE(mode_4208x3118_regs),
> + .regs = mode_4208x3118_regs,
> + },
> + .link_freq_index = 0,
...use the indices defined above here. This way we have an explicit
link between both arrays and it's not possible to accidentally break
it.
[snip]
> +
> + /* Mutex for serialized access */
> + struct mutex mutex;
Please document what needs to be serialized.
> +
> + /* Streaming on/off */
> + bool streaming;
> +};
> +
> +#define to_imx258(_sd) container_of(_sd, struct imx258, sd)
Please use a static inline for compiler type safety.
> +
> +/* Read registers up to 4 at a time */
> +static int imx258_read_reg(struct imx258 *imx258, u16 reg, u32 len, u32 *val)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
> + struct i2c_msg msgs[2];
> + u8 *data_be_p;
> + int ret;
> + u32 data_be = 0;
> + u16 reg_addr_be = cpu_to_be16(reg);
> +
> + if (len > 4)
> + return -EINVAL;
> +
> + data_be_p = (u8 *)&data_be;
> + /* Write register address */
> + msgs[0].addr = client->addr;
> + msgs[0].flags = 0;
> + msgs[0].len = 2;
> + msgs[0].buf = (u8 *)®_addr_be;
No need for this big endian and pointer cast magic. Let's make this a
bit more readable:
u8 addr_buf[2] = { reg >> 8, reg & 0xff };
[...]
msgs[0].len = ARRAY_SIZE(addr_buf);
msgs[0].buf = addr_buf;
> +
> + /* Read data from register */
> + msgs[1].addr = client->addr;
> + msgs[1].flags = I2C_M_RD;
> + msgs[1].len = len;
> + msgs[1].buf = &data_be_p[4 - len];
u8 data_buf[4] = { 0, };
[...]
msgs[1].buf = &data_buf[4 - len];
> +
> + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> + if (ret != ARRAY_SIZE(msgs))
> + return -EIO;
> +
> + *val = be32_to_cpu(data_be);
*val = get_unaligned_be32(data_buf);
> +
> + return 0;
> +}
> +
> +/* Write registers up to 4 at a time */
> +static int imx258_write_reg(struct imx258 *imx258, u16 reg, u32 len, u32 val)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
> + int buf_i, val_i;
> + u8 buf[6], *val_p;
> +
> + if (len > 4)
> + return -EINVAL;
> +
> + buf[0] = reg >> 8;
> + buf[1] = reg & 0xff;
> +
> + val = cpu_to_be32(val);
> + val_p = (u8 *)&val;
> + buf_i = 2;
> + val_i = 4 - len;
> +
> + while (val_i < 4)
> + buf[buf_i++] = val_p[val_i++];
Similar thing here. The above 7 lines are the same as:
put_unaligned_be32(val << (8 * (4 - len)), buf);
> +
> + if (i2c_master_send(client, buf, len + 2) != len + 2)
> + return -EIO;
> +
> + return 0;
> +}
> +
> +/* Write a list of registers */
> +static int imx258_write_regs(struct imx258 *imx258,
> + const struct imx258_reg *regs, u32 len)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
> + int ret;
> + u32 i;
> +
> + for (i = 0; i < len; i++) {
> + ret = imx258_write_reg(imx258, regs[i].address, 1,
> + regs[i].val);
> + if (ret) {
> + dev_err_ratelimited(
> + &client->dev,
> + "Failed to write reg 0x%4.4x. error = %d\n",
> + regs[i].address, ret);
> +
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int imx258_write_reg_list(struct imx258 *imx258,
> + const struct imx258_reg_list *r_list)
> +{
> + return imx258_write_regs(imx258, r_list->regs, r_list->num_of_regs);
This is the only place where imx258_write_regs() is used. Is there any
need to make it a separate function?
> +}
> +
> +/* Open sub-device */
> +static int imx258_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> + struct v4l2_mbus_framefmt *try_fmt =
> + v4l2_subdev_get_try_format(sd, fh->pad, 0);
> +
> + /* Initialize try_fmt */
> + try_fmt->width = supported_modes[0].width;
> + try_fmt->height = supported_modes[0].height;
> + try_fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> + try_fmt->field = V4L2_FIELD_NONE;
> +
> + return 0;
> +}
> +
> +static int imx258_i2c_write_reg_ext(struct imx258 *imx258, u16 reg,
> + u32 len, u32 val)
> +{
> + u32 val_d, val_d2;
> + int ret;
> + u32 mask = 0xff;
> +
> + val_d = (val & ~mask) >> 8;
> + val_d2 = val & mask;
> +
> + ret = imx258_write_reg(imx258, reg, len/2, val_d);
> + ret = imx258_write_reg(imx258, reg+1, len/2, val_d2);
> +
> + if (ret)
> + return ret;
> + return 0;
> +}
What is this function for? I don't see why imx258_write_reg() couldn't
be called directly...
> +
> +static int imx258_update_digital_gain(struct imx258 *imx258, u32 len, u32 val)
> +{
> + int ret;
> +
> + ret = imx258_i2c_write_reg_ext(imx258, IMX258_REG_GR_DIGITAL_GAIN,
> + IMX258_REG_VALUE_16BIT,
> + val);
> + ret |= imx258_i2c_write_reg_ext(imx258, IMX258_REG_GB_DIGITAL_GAIN,
> + IMX258_REG_VALUE_16BIT,
> + val);
> + ret |= imx258_i2c_write_reg_ext(imx258, IMX258_REG_R_DIGITAL_GAIN,
> + IMX258_REG_VALUE_16BIT,
> + val);
> + ret |= imx258_i2c_write_reg_ext(imx258, IMX258_REG_B_DIGITAL_GAIN,
> + IMX258_REG_VALUE_16BIT,
> + val);
Please don't do bitwise OR on return values. If two or more of the
above calls return different non-zero values, the resulting value will
make no sense.
> + if (ret)
> + return ret;
> + return 0;
> +}
> +
> +static int imx258_set_ctrl(struct v4l2_ctrl *ctrl)
> +{
> + struct imx258 *imx258 =
> + container_of(ctrl->handler, struct imx258, ctrl_handler);
> + struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
> + int ret = 0;
> + /*
> + * Applying V4L2 control value only happens
> + * when power is up for streaming
> + */
> + if (pm_runtime_get_if_in_use(&client->dev) <= 0)
> + return 0;
I thought we decided to fix this to handle disabled runtime PM properly.
> +
> + switch (ctrl->id) {
> + case V4L2_CID_ANALOGUE_GAIN:
> + ret = imx258_i2c_write_reg_ext(imx258, IMX258_REG_ANALOG_GAIN,
> + IMX258_REG_VALUE_16BIT,
> + ctrl->val);
> + break;
> + case V4L2_CID_EXPOSURE:
> + ret = imx258_i2c_write_reg_ext(imx258, IMX258_REG_EXPOSURE,
> + IMX258_REG_VALUE_16BIT,
> + ctrl->val);
> + break;
> + case V4L2_CID_DIGITAL_GAIN:
> + ret = imx258_update_digital_gain(imx258, IMX258_REG_VALUE_16BIT,
> + ctrl->val);
> + break;
> + default:
> + dev_info(&client->dev,
> + "ctrl(id:0x%x,val:0x%x) is not handled\n",
> + ctrl->id, ctrl->val);
dev_err() and set ret to an error.
> + break;
> + }
> +
> + pm_runtime_put(&client->dev);
> +
> + return ret;
> +}
[snip]
> +/* Start streaming */
> +static int imx258_start_streaming(struct imx258 *imx258)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
> + const struct imx258_reg_list *reg_list;
> + int ret, link_freq_index;
> +
> + /* Setup PLL */
> + link_freq_index = imx258->cur_mode->link_freq_index;
> + reg_list = &link_freq_configs[link_freq_index].reg_list;
> + ret = imx258_write_reg_list(imx258, reg_list);
> + if (ret) {
> + dev_err(&client->dev, "%s failed to set plls\n", __func__);
> + return ret;
> + }
> +
> + /* Apply default values of current mode */
> + reg_list = &imx258->cur_mode->reg_list;
> + ret = imx258_write_reg_list(imx258, reg_list);
> + if (ret) {
> + dev_err(&client->dev, "%s failed to set mode\n", __func__);
> + return ret;
> + }
> +
> + /* Set Orientation be 180 degree */
> + ret = imx258_write_reg(imx258, REG_MIRROR_FLIP_CONTROL,
> + IMX258_REG_VALUE_08BIT, REG_CONFIG_MIRROR_FLIP);
> + if (ret) {
> + dev_err(&client->dev, "%s failed to set orientation\n",
> + __func__);
> + return ret;
> + }
> +
> + /* Apply customized values from user */
> + ret = __v4l2_ctrl_handler_setup(imx258->sd.ctrl_handler);
> + if (ret)
> + return ret;
> +
> + usleep_range(12000, 13000);
Please add a comment explaining what this usleep_range() is waiting for.
> +
> + /* set stream on register */
> + return imx258_write_reg(imx258, IMX258_REG_MODE_SELECT,
> + IMX258_REG_VALUE_08BIT,
> + IMX258_MODE_STREAMING);
> +}
[snip]
> +/* Initialize control handlers */
> +static int imx258_init_controls(struct imx258 *imx258)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&imx258->sd);
> + struct v4l2_ctrl_handler *ctrl_hdlr;
> + s64 exposure_max;
> + s64 vblank_def;
> + s64 vblank_min;
> + s64 pixel_rate_min;
> + s64 pixel_rate_max;
> + int ret;
> +
> + ctrl_hdlr = &imx258->ctrl_handler;
> + ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
> + if (ret)
Missing error message.
> + return ret;
> +
> + mutex_init(&imx258->mutex);
> + ctrl_hdlr->lock = &imx258->mutex;
> + imx258->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> + &imx258_ctrl_ops,
> + V4L2_CID_LINK_FREQ,
> + ARRAY_SIZE(link_freq_menu_items) - 1,
> + 0,
> + link_freq_menu_items);
> +
> + if (!imx258->link_freq) {
> + ret = -EINVAL;
Missing error message.
> + goto error;
> + }
> +
> + imx258->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> + pixel_rate_max = link_freq_to_pixel_rate(link_freq_menu_items[0]);
> + pixel_rate_min = link_freq_to_pixel_rate(link_freq_menu_items[1]);
> + /* By default, PIXEL_RATE is read only */
> + imx258->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, &imx258_ctrl_ops,
> + V4L2_CID_PIXEL_RATE,
> + pixel_rate_min, pixel_rate_max,
> + 1, pixel_rate_max);
> +
> +
> + vblank_def = imx258->cur_mode->vts_def - imx258->cur_mode->height;
> + vblank_min = imx258->cur_mode->vts_min - imx258->cur_mode->height;
> + imx258->vblank = v4l2_ctrl_new_std(
> + ctrl_hdlr, &imx258_ctrl_ops, V4L2_CID_VBLANK,
> + vblank_min,
> + IMX258_VTS_MAX - imx258->cur_mode->height, 1,
> + vblank_def);
> +
> + imx258->hblank = v4l2_ctrl_new_std(
> + ctrl_hdlr, &imx258_ctrl_ops, V4L2_CID_HBLANK,
> + IMX258_PPL_650MHZ - imx258->cur_mode->width,
> + IMX258_PPL_650MHZ - imx258->cur_mode->width,
> + 1,
> + IMX258_PPL_650MHZ - imx258->cur_mode->width);
> +
> + if (!imx258->hblank) {
> + ret = -EINVAL;
> + goto error;
> + }
Why checking hblank, but not other controls? I think in this case just
the general check for ctrl_hdlr->error should be enough.
> +
> + imx258->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +
> + exposure_max = imx258->cur_mode->vts_def - 8;
> + imx258->exposure = v4l2_ctrl_new_std(
> + ctrl_hdlr, &imx258_ctrl_ops,
> + V4L2_CID_EXPOSURE, IMX258_EXPOSURE_MIN,
> + IMX258_EXPOSURE_MAX, IMX258_EXPOSURE_STEP,
> + IMX258_EXPOSURE_DEFAULT);
> +
> + v4l2_ctrl_new_std(ctrl_hdlr, &imx258_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
> + IMX258_ANA_GAIN_MIN, IMX258_ANA_GAIN_MAX,
> + IMX258_ANA_GAIN_STEP, IMX258_ANA_GAIN_DEFAULT);
> +
> + v4l2_ctrl_new_std(ctrl_hdlr, &imx258_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
> + IMX258_DGTL_GAIN_MIN, IMX258_DGTL_GAIN_MAX,
> + IMX258_DGTL_GAIN_STEP, IMX258_DGTL_GAIN_DEFAULT);
> +
> + v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &imx258_ctrl_ops,
> + V4L2_CID_TEST_PATTERN,
> + ARRAY_SIZE(imx258_test_pattern_menu) - 1,
> + 0, 0, imx258_test_pattern_menu);
> +
> + if (ctrl_hdlr->error) {
> + ret = ctrl_hdlr->error;
> + dev_err(&client->dev, "%s control init failed (%d)\n",
> + __func__, ret);
> + goto error;
> + }
> +
> + imx258->sd.ctrl_handler = ctrl_hdlr;
> +
> + return 0;
> +
> +error:
> + v4l2_ctrl_handler_free(ctrl_hdlr);
> + mutex_destroy(&imx258->mutex);
> +
> + return ret;
> +}
> +
> +static void imx258_free_controls(struct imx258 *imx258)
> +{
> + v4l2_ctrl_handler_free(imx258->sd.ctrl_handler);
> + mutex_destroy(&imx258->mutex);
> +}
> +
> +static int imx258_probe(struct i2c_client *client)
> +{
> + struct imx258 *imx258;
> + int ret;
> + u32 val = 0;
> +
> + device_property_read_u32(&client->dev, "clock-frequency", &val);
> + if (val != 19200000)
Would be nice to print some error.
> + return -EINVAL;
> +
> + imx258 = devm_kzalloc(&client->dev, sizeof(*imx258), GFP_KERNEL);
> + if (!imx258)
> + return -ENOMEM;
> +
> + /* Initialize subdev */
> + v4l2_i2c_subdev_init(&imx258->sd, client, &imx258_subdev_ops);
> +
> + /* Check module identity */
> + ret = imx258_identify_module(imx258);
> + if (ret)
> + return ret;
> +
> + /* Set default mode to max resolution */
> + imx258->cur_mode = &supported_modes[0];
> +
> + ret = imx258_init_controls(imx258);
> + if (ret)
> + return ret;
> +
> + /* Initialize subdev */
> + imx258->sd.internal_ops = &imx258_internal_ops;
> + imx258->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> + imx258->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> +
> + /* Initialize source pad */
> + imx258->pad.flags = MEDIA_PAD_FL_SOURCE;
> +
> + ret = media_entity_pads_init(&imx258->sd.entity, 1, &imx258->pad);
> + if (ret) {
> + dev_err(&client->dev, "%s failed:%d\n", __func__, ret);
This isn't a very useful error message. "media_entity_pads_init()
failed: %d\n" would make more sense.
Best regards,
Tomasz
