[PATCH 4.17 011/324] drm/bridge/sii8620: fix display modes validation

Greg Kroah-Hartman
2018-08-23T08:39:42Z

From: Maciej Purski <m.purski@samsung.com>

[ Upstream commit ecba7cfa3afbe489288f2c819158b7402afd7ee9 ]

Current implementation of mode_valid() and mode_fixup() callbacks
handle packed pixel modes improperly.

Fix it by using proper maximum clock values from the documentation.

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1517568865-25219-1-git-send-email-m.purski@samsung.com
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/bridge/sil-sii8620.c | 78 +++++++++++++++++------------------
1 file changed, 40 insertions(+), 38 deletions(-)

--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -36,8 +36,11 @@

#define SII8620_BURST_BUF_LEN 288
#define VAL_RX_HDMI_CTRL2_DEFVAL VAL_RX_HDMI_CTRL2_IDLE_CNT(3)
-#define MHL1_MAX_LCLK 225000
-#define MHL3_MAX_LCLK 600000
+
+#define MHL1_MAX_PCLK 75000
+#define MHL1_MAX_PCLK_PP_MODE 150000
+#define MHL3_MAX_PCLK 200000
+#define MHL3_MAX_PCLK_PP_MODE 300000

enum sii8620_mode {
CM_DISCONNECTED,
@@ -2277,17 +2280,43 @@ static void sii8620_detach(struct drm_br
rc_unregister_device(ctx->rc_dev);
}

+static int sii8620_is_packing_required(struct sii8620 *ctx,
+ const struct drm_display_mode *mode)
+{
+ int max_pclk, max_pclk_pp_mode;
+
+ if (sii8620_is_mhl3(ctx)) {
+ max_pclk = MHL3_MAX_PCLK;
+ max_pclk_pp_mode = MHL3_MAX_PCLK_PP_MODE;
+ } else {
+ max_pclk = MHL1_MAX_PCLK;
+ max_pclk_pp_mode = MHL1_MAX_PCLK_PP_MODE;
+ }
+
+ if (mode->clock < max_pclk)
+ return 0;
+ else if (mode->clock < max_pclk_pp_mode)
+ return 1;
+ else
+ return -1;
+}
+
static enum drm_mode_status sii8620_mode_valid(struct drm_bridge *bridge,
const struct drm_display_mode *mode)
{
struct sii8620 *ctx = bridge_to_sii8620(bridge);
+ int pack_required = sii8620_is_packing_required(ctx, mode);
bool can_pack = ctx->devcap[MHL_DCAP_VID_LINK_MODE] &
MHL_DCAP_VID_LINK_PPIXEL;
- unsigned int max_pclk = sii8620_is_mhl3(ctx) ? MHL3_MAX_LCLK :
- MHL1_MAX_LCLK;
- max_pclk /= can_pack ? 2 : 3;

- return (mode->clock > max_pclk) ? MODE_CLOCK_HIGH : MODE_OK;
+ switch (pack_required) {
+ case 0:
+ return MODE_OK;
+ case 1:
+ return (can_pack) ? MODE_OK : MODE_CLOCK_HIGH;
+ default:
+ return MODE_CLOCK_HIGH;
+ }
}

static bool sii8620_mode_fixup(struct drm_bridge *bridge,
@@ -2295,43 +2324,16 @@ static bool sii8620_mode_fixup(struct dr
struct drm_display_mode *adjusted_mode)
{
struct sii8620 *ctx = bridge_to_sii8620(bridge);
- int max_lclk;
- bool ret = true;

mutex_lock(&ctx->lock);

- max_lclk = sii8620_is_mhl3(ctx) ? MHL3_MAX_LCLK : MHL1_MAX_LCLK;
- if (max_lclk > 3 * adjusted_mode->clock) {
- ctx->use_packed_pixel = 0;
- goto end;
- }
- if ((ctx->devcap[MHL_DCAP_VID_LINK_MODE] & MHL_DCAP_VID_LINK_PPIXEL) &&
- max_lclk > 2 * adjusted_mode->clock) {
- ctx->use_packed_pixel = 1;
- goto end;
- }
- ret = false;
-end:
- if (ret) {
- u8 vic = drm_match_cea_mode(adjusted_mode);
+ ctx->use_packed_pixel = sii8620_is_packing_required(ctx, adjusted_mode);
+ ctx->video_code = drm_match_cea_mode(adjusted_mode);
+ ctx->pixel_clock = adjusted_mode->clock;

- if (!vic) {
- union hdmi_infoframe frm;
- u8 mhl_vic[] = { 0, 95, 94, 93, 98 };
-
- /* FIXME: We need the connector here */
- drm_hdmi_vendor_infoframe_from_display_mode(
- &frm.vendor.hdmi, NULL, adjusted_mode);
- vic = frm.vendor.hdmi.vic;
- if (vic >= ARRAY_SIZE(mhl_vic))
- vic = 0;
- vic = mhl_vic[vic];
- }
- ctx->video_code = vic;
- ctx->pixel_clock = adjusted_mode->clock;
- }
mutex_unlock(&ctx->lock);
- return ret;
+
+ return true;
}

static const struct drm_bridge_funcs sii8620_bridge_funcs = {