drm/bridge/sii8620: fix loops in EDID fetch logic (8e627a1b) · Commits · 戴 / test

drivers/gpu/drm/bridge/sil-sii8620.c

+20 −11

Original line number	Diff line number	Diff line
		@@ -807,6 +807,7 @@ static void sii8620_burst_rx_all(struct sii8620 *ctx)
		static void sii8620_fetch_edid(struct sii8620 *ctx)
		{
		u8 lm_ddc, ddc_cmd, int3, cbus;
		unsigned long timeout;
		int fetched, i;
		int edid_len = EDID_LENGTH;
		u8 *edid;
		@@ -856,23 +857,31 @@ static void sii8620_fetch_edid(struct sii8620 *ctx)
		REG_DDC_CMD, ddc_cmd \| VAL_DDC_CMD_ENH_DDC_READ_NO_ACK
		);

		do {
		int3 = sii8620_readb(ctx, REG_INTR3);
		int3 = 0;
		timeout = jiffies + msecs_to_jiffies(200);
		for (;;) {
		cbus = sii8620_readb(ctx, REG_CBUS_STATUS);

		if (int3 & BIT_DDC_CMD_DONE)
		if (~cbus & BIT_CBUS_STATUS_CBUS_CONNECTED) {
		kfree(edid);
		edid = NULL;
		goto end;
		}
		if (int3 & BIT_DDC_CMD_DONE) {
		if (sii8620_readb(ctx, REG_DDC_DOUT_CNT)
		>= FETCH_SIZE)
		break;

		if (!(cbus & BIT_CBUS_STATUS_CBUS_CONNECTED)) {
		} else {
		int3 = sii8620_readb(ctx, REG_INTR3);
		}
		if (time_is_before_jiffies(timeout)) {
		ctx->error = -ETIMEDOUT;
		dev_err(ctx->dev, "timeout during EDID read\n");
		kfree(edid);
		edid = NULL;
		goto end;
		}
		} while (1);

		sii8620_readb(ctx, REG_DDC_STATUS);
		while (sii8620_readb(ctx, REG_DDC_DOUT_CNT) < FETCH_SIZE)
		usleep_range(10, 20);
		}

		sii8620_read_buf(ctx, REG_DDC_DATA, edid + fetched, FETCH_SIZE);
		if (fetched + FETCH_SIZE == EDID_LENGTH) {