Re: [PATCH v14 3/3] media: i2c: Add support for alvium camera

From: Tommaso Merciai
Date: Mon Dec 04 2023 - 04:32:46 EST

Hi Sakari,

On Mon, Dec 04, 2023 at 09:30:24AM +0000, Sakari Ailus wrote:
> Hi Tommaso,
>
> On Sat, Dec 02, 2023 at 10:32:11AM +0100, Tommaso Merciai wrote:
> > Hi Sakari,
> > Thanks for your comments.
> >
> > On Fri, Dec 01, 2023 at 09:00:33PM +0000, Sakari Ailus wrote:
> > > Hi Tommaso,
> > >
> > > A few more comments below...
> > >
> > > On Fri, Nov 24, 2023 at 10:30:07AM +0100, Tommaso Merciai wrote:
> > >
> > > ...
> > >
> > > > +static int alvium_get_bcrm_vers(struct alvium_dev *alvium)
> > > > +{
> > > > + struct device *dev = &alvium->i2c_client->dev;
> > > > + struct alvium_bcrm_vers *v;
> > > > + u64 val;
> > > > + int ret;
> > > > +
> > > > + ret = alvium_read(alvium, REG_BCRM_VERSION_R, &val, NULL);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + v = (struct alvium_bcrm_vers *)&val;
> > >
> > > You're still reading the entire struct using a single read. :-( This won't
> > > work on a BE machine as while the struct fields are in the same memory
> > > locations, the respective data in a single 64-bit value is not.
> >
> > What about splitting REG_BCRM_VERSION_R in:
> >
> > #define REG_BCRM_MINOR_VERSION_R CCI_REG16(0x0000)
> > #define REG_BCRM_MAJOR_VERSION_R CCI_REG16(0x0002)
> >
> > and REG_BCRM_DEVICE_FIRMWARE_VERSION_R in:
> >
> > #define REG_BCRM_DEVICE_FW_SPEC_VERSION_R REG_BCRM_V4L2_8BIT(0x0010)
> > #define REG_BCRM_DEVICE_FW_MAJOR_VERSION_R REG_BCRM_V4L2_8BIT(0x0011)
> > #define REG_BCRM_DEVICE_FW_MINOR_VERSION_R REG_BCRM_V4L2_16BIT(0x0012)
> > #define REG_BCRM_DEVICE_FW_PATCH_VERSION_R REG_BCRM_V4L2_32BIT(0x0014)
> >
> >
> > Then reading those values as a single values as you suggest:
> >
> > static int alvium_get_bcrm_vers(struct alvium_dev *alvium)
> > {
> > struct device *dev = &alvium->i2c_client->dev;
> > u64 min, maj;
> > int ret = 0;
> >
> > ret = alvium_read(alvium, REG_BCRM_MINOR_VERSION_R, &min, &ret);
> > ret = alvium_read(alvium, REG_BCRM_MAJOR_VERSION_R, &maj, &ret);
> > if (ret)
> > return ret;
> >
> > dev_info(dev, "bcrm version: %llu.%llu\n", min, maj);
> >
> > return 0;
> > }
> >
> > static int alvium_get_fw_version(struct alvium_dev *alvium)
> > {
> > struct device *dev = &alvium->i2c_client->dev;
> > u64 spec, maj, min, pat;
> > int ret = 0;
> >
> > ret = alvium_read(alvium, REG_BCRM_DEVICE_FW_SPEC_VERSION_R, &spec, &ret);
> > ret = alvium_read(alvium, REG_BCRM_DEVICE_FW_MAJOR_VERSION_R, &maj, &ret);
> > ret = alvium_read(alvium, REG_BCRM_DEVICE_FW_MINOR_VERSION_R, &min, &ret);
> > ret = alvium_read(alvium, REG_BCRM_DEVICE_FW_PATCH_VERSION_R, &pat, &ret);
> > if (ret)
> > return ret;
> >
> > dev_info(dev, "fw version: %llu.%llu.%llu.%llu\n", spec, maj, min, pat);
> >
> > return 0;
> > }
> >
> > Then I'm going to remove alvium_bcrm_vers and alvium_fw_vers.
> > And alvium_is_alive became:
> >
> > static int alvium_is_alive(struct alvium_dev *alvium)
> > {
> > u64 bcrm, hbeat;
> > int ret = 0;
> >
> > alvium_read(alvium, REG_BCRM_MINOR_VERSION_R, &bcrm, &ret);
> > alvium_read(alvium, REG_BCRM_HEARTBEAT_RW, &hbeat, &ret);
> > if (ret)
> > return ret;
> >
> > return hbeat;
> > }
> >
> > What do you think? Let me know.
> > (Maybe is this that you are trying to explain me but I haven't catch,
> > sorry) :)
>
> Yes. The above code looks good to me.

I'm going to send v15 then.
Thanks.

Regards,
Tommaso

>
> >
> >
> > >
> > > > +
> > > > + dev_info(dev, "bcrm version: %u.%u\n", v->minor, v->major);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int alvium_get_fw_version(struct alvium_dev *alvium)
> > > > +{
> > > > + struct device *dev = &alvium->i2c_client->dev;
> > > > + struct alvium_fw_vers *fw_v;
> > > > + u64 val;
> > > > + int ret;
> > > > +
> > > > + ret = alvium_read(alvium, REG_BCRM_DEVICE_FIRMWARE_VERSION_R, &val, NULL);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + fw_v = (struct alvium_fw_vers *)&val;
> > >
> > > Same here.
> > >
> > > > +
> > > > + dev_info(dev, "fw version: %u.%u.%u.%u\n", fw_v->special, fw_v->major,
> > > > + fw_v->minor, fw_v->patch);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int alvium_get_bcrm_addr(struct alvium_dev *alvium)
> > > > +{
> > > > + u64 val;
> > > > + int ret;
> > > > +
> > > > + ret = alvium_read(alvium, REG_BCRM_REG_ADDR_R, &val, NULL);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + alvium->bcrm_addr = val;
> > > > +
> > > > + return 0;
> > > > +}
> > >
> > > ...
> > >
> > > > +static int alvium_setup_mipi_fmt(struct alvium_dev *alvium)
> > > > +{
> > > > + unsigned int avail_fmt_cnt = 0;
> > > > + unsigned int fmt = 0;
> > > > + size_t sz = 0;
> > > > +
> > > > + alvium->alvium_csi2_fmt = NULL;
> > >
> > > This seems to be unnnecessary: the field is assigned below without using it
> > > (obviously).
> >
> > Ok, I will remove this in v15.
> >
> > >
> > > > +
> > > > + /* calculate fmt array size */
> > > > + for (fmt = 0; fmt < ALVIUM_NUM_SUPP_MIPI_DATA_FMT; fmt++) {
> > > > + if (!alvium->is_mipi_fmt_avail[alvium_csi2_fmts[fmt].fmt_av_bit])
> > > > + continue;
> > > > +
> > > > + if ((!alvium_csi2_fmts[fmt].is_raw) ||
> > > > + (alvium->is_bay_avail[alvium_csi2_fmts[fmt].bay_av_bit]))
> > > > + sz++;
> > > > + }
> > > > +
> > > > + /* init alvium_csi2_fmt array */
> > > > + alvium->alvium_csi2_fmt_n = sz;
> > > > + alvium->alvium_csi2_fmt =
> > > > + kmalloc_array(sz, sizeof(struct alvium_pixfmt), GFP_KERNEL);
> > > > + if (!alvium->alvium_csi2_fmt)
> > > > + return -ENOMEM;
> > > > +
> > > > + /* Create the alvium_csi2 fmt array from formats available */
> > > > + for (fmt = 0; fmt < ALVIUM_NUM_SUPP_MIPI_DATA_FMT; fmt++) {
> > > > + if (!alvium->is_mipi_fmt_avail[alvium_csi2_fmts[fmt].fmt_av_bit])
> > > > + continue;
> > > > +
> > > > + if ((!alvium_csi2_fmts[fmt].is_raw) ||
> > > > + (alvium->is_bay_avail[alvium_csi2_fmts[fmt].bay_av_bit])) {
> > > > + alvium->alvium_csi2_fmt[avail_fmt_cnt] = alvium_csi2_fmts[fmt];
> > > > + avail_fmt_cnt++;
> > > > + }
> > > > + }
> > > > +
> > > > + return 0;
> > > > +}
> > >
> > > ...
> > >
> > > > +static const struct alvium_pixfmt *
> > > > +alvium_code_to_pixfmt(struct alvium_dev *alvium, u32 code)
> > > > +{
> > > > + const struct alvium_pixfmt *formats = alvium->alvium_csi2_fmt;
> > >
> > > I'd use alvium->alvium_csi2_fmt and not add a local variable. Up to you.
> >
> > Ok also for me.
> >
> > >
> > > > + unsigned int i;
> > > > +
> > > > + for (i = 0; formats[i].code; ++i)
> > > > + if (formats[i].code == code)
> > > > + return &formats[i];
> > > > +
> > > > + return &formats[0];
> > > > +}
> > > > +
> > > > +static int alvium_set_mode(struct alvium_dev *alvium,
> > > > + struct v4l2_subdev_state *state)
> > > > +{
> > > > + struct v4l2_mbus_framefmt *fmt;
> > > > + struct v4l2_rect *crop;
> > > > + int ret;
> > > > +
> > > > + crop = v4l2_subdev_state_get_crop(state, 0);
> > > > + fmt = v4l2_subdev_state_get_format(state, 0);
> > > > +
> > > > + v4l_bound_align_image(&fmt->width, alvium->img_min_width,
> > > > + alvium->img_max_width, 0,
> > > > + &fmt->height, alvium->img_min_height,
> > > > + alvium->img_max_height, 0, 0);
> > > > +
> > > > + /* alvium don't accept negative crop left/top */
> > > > + crop->left = clamp((u32)max(0, crop->left), alvium->min_offx,
> > > > + (u32)(alvium->img_max_width - fmt->width));
> > > > + crop->top = clamp((u32)max(0, crop->top), alvium->min_offy,
> > > > + (u32)(alvium->img_max_height - fmt->height));
> > > > +
> > > > + ret = alvium_set_img_width(alvium, fmt->width);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + ret = alvium_set_img_height(alvium, fmt->height);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + ret = alvium_set_img_offx(alvium, crop->left);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + ret = alvium_set_img_offy(alvium, crop->top);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + return 0;
> > > > +}
> >
> > I'm going to rebase v15 on top of your master branch.
> > My plan is moving alvium_init_cfg now alvium_init_state into
> > v4l2_subdev_internal_ops.
>
> Ack, thanks!
>
> --
> Regards,
>
> Sakari Ailus