Hi Jakob,
thanks for your patch!
On Thu, Oct 24, 2024 at 5:18 AM Jakob Hauser <jahau@xxxxxxxxxxxxxx> wrote:
> +static const int s6e88a0_ams427ap24_br_to_cd[NUM_STEPS_CANDELA] = {
(...)
> + /* brightness till, candela */
Brightness to candela conversion table? Edit comment?
> +static const u8 s6e88a0_ams427ap24_aid[NUM_STEPS_AID][SEQ_LENGTH_AID] = {
If you know that the sequence 0xb2, 0x40, 0x08, 0x20 means "set AID"
(or is it AOR??) you can #define
#define S6E88A0_SET_AID 0xb2
Then make a small buffer:
u8 set_aid[5] = { S6E88A0_SET_AID, 0x40, 0x08, 0x20, 0x00, 0x00 };
then you can strip the first three bytes from the entire table,
just copy in the two relevant bytes into set_aor[]
and send that.
> +static const u8 s6e88a0_ams427ap24_elvss[NUM_STEPS_ELVSS][SEQ_LENGTH_ELVSS] = {
> + { 0x28, 0x14 }, /* 10CD ~ 111CD */
> + { 0x28, 0x13 }, /* 119CD */
Command 0xb6 is
#define S6E88A0_SET_LVSS 0xb6
Same comment: just define
u8 set_lvss[2] = {S6E88A0_SET_LVSS, 0x28, 0x00};
copy the second byte into the command, this becomes
an array of single bytes.
> +static const u8 s6e88a0_ams427ap24_gamma[NUM_STEPS_CANDELA][SEQ_LENGTH_GAMMA] = {
> + /* 10CD */
> + { 0x00, 0xc8, 0x00, 0xc4, 0x00, 0xc5, 0x8c, 0x8a, 0x8a, 0x8c, 0x8b,
> + 0x8c, 0x87, 0x89, 0x89, 0x88, 0x87, 0x8c, 0x80, 0x82, 0x88, 0x7b,
> + 0x72, 0x8c, 0x60, 0x68, 0x8c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
This array looks fine though, it seems to be all unique gamma calibration.
> +static int s6e88a0_ams427ap24_set_brightness(struct backlight_device *bd)
> +{
> + struct s6e88a0_ams427ap24 *ctx = bl_get_data(bd);
> + struct mipi_dsi_device *dsi = ctx->dsi;
> + struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };
> + struct device *dev = &dsi->dev;
> + int brightness = bd->props.brightness;
> + int candela_enum;
> + u8 b2[SEQ_LENGTH_AID + 1];
> + u8 b6[SEQ_LENGTH_ELVSS + 1];
> + u8 ca[SEQ_LENGTH_GAMMA + 1];
Rename them to something like my suggestions so we understand what it is
all about. It seems the infrastructure for what I suggested is mostly already
there.
See comment above how to modify arrays to contain stuff that is always
the same.
> + /* get aid */
> + b2[0] = 0xb2;
Use a define per above.
> + switch (candela_enum) {
> + case CANDELA_10CD ... CANDELA_105CD:
> + memcpy(&b2[1], s6e88a0_ams427ap24_aid[candela_enum],
> + SEQ_LENGTH_AID);
> + break;
> + case CANDELA_111CD ... CANDELA_172CD:
> + memcpy(&b2[1], s6e88a0_ams427ap24_aid[CANDELA_111CD],
> + SEQ_LENGTH_AID);
> + break;
> + case CANDELA_183CD ... CANDELA_300CD:
> + memcpy(&b2[1], s6e88a0_ams427ap24_aid[CANDELA_111CD + 1],
> + SEQ_LENGTH_AID);
> + break;
> + default:
> + dev_err(dev, "Failed to get aid data\n");
> + return -EINVAL;
> + }
> +
> + /* get elvss */
> + b6[0] = 0xb6;
Use a define per above.
> + if (candela_enum <= CANDELA_111CD) {
> + memcpy(&b6[1], s6e88a0_ams427ap24_elvss[0], SEQ_LENGTH_ELVSS);
> + } else {
> + memcpy(&b6[1], s6e88a0_ams427ap24_elvss[candela_enum - CANDELA_111CD],
> + SEQ_LENGTH_ELVSS);
> + }
> +
> + /* get gamma */
> + ca[0] = 0xca;
#define S6E88A0_SET_GAMMA 0xca
> + memcpy(&ca[1], s6e88a0_ams427ap24_gamma[candela_enum], SEQ_LENGTH_GAMMA);
> +
> + /* write: key on, aid, acl off, elvss, gamma, gamma update, key off */
> + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0, 0x5a, 0x5a);
0xf0 is clearly an unlocking key as per comment in the previous patch.
> + mipi_dsi_dcs_write_buffer_multi(&dsi_ctx, b2, ARRAY_SIZE(b2));
> + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x55, 0x00);
0x55 is MIPI_DCS_WRITE_POWER_SAVE in <video/mipi_display.h>
> + mipi_dsi_dcs_write_buffer_multi(&dsi_ctx, b6, ARRAY_SIZE(b6));
> + mipi_dsi_dcs_write_buffer_multi(&dsi_ctx, ca, ARRAY_SIZE(ca));
> + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf7, 0x03);
> + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0, 0xa5, 0xa5);
Clearly this locks the L2 access again.
Yours,
Linus Walleij
