static int mmc_sd_init_card()

in core/sd.c [1390:1572]

• 124 lines of code
• 44 McCabe index (conditional complexity)

static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
	struct mmc_card *oldcard)
{
	struct mmc_card *card;
	int err;
	u32 cid[4];
	u32 rocr = 0;
	bool v18_fixup_failed = false;

	WARN_ON(!host->claimed);
retry:
	err = mmc_sd_get_cid(host, ocr, cid, &rocr);
	if (err)
		return err;

	if (oldcard) {
		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
			pr_debug("%s: Perhaps the card was replaced\n",
				mmc_hostname(host));
			return -ENOENT;
		}

		card = oldcard;
	} else {
		/*
		 * Allocate card structure.
		 */
		card = mmc_alloc_card(host, &sd_type);
		if (IS_ERR(card))
			return PTR_ERR(card);

		card->ocr = ocr;
		card->type = MMC_TYPE_SD;
		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
	}

	/*
	 * Call the optional HC's init_card function to handle quirks.
	 */
	if (host->ops->init_card)
		host->ops->init_card(host, card);

	/*
	 * For native busses:  get card RCA and quit open drain mode.
	 */
	if (!mmc_host_is_spi(host)) {
		err = mmc_send_relative_addr(host, &card->rca);
		if (err)
			goto free_card;
	}

	if (!oldcard) {
		err = mmc_sd_get_csd(card);
		if (err)
			goto free_card;

		mmc_decode_cid(card);
	}

	/*
	 * handling only for cards supporting DSR and hosts requesting
	 * DSR configuration
	 */
	if (card->csd.dsr_imp && host->dsr_req)
		mmc_set_dsr(host);

	/*
	 * Select card, as all following commands rely on that.
	 */
	if (!mmc_host_is_spi(host)) {
		err = mmc_select_card(card);
		if (err)
			goto free_card;
	}

	err = mmc_sd_setup_card(host, card, oldcard != NULL);
	if (err)
		goto free_card;

	/*
	 * If the card has not been power cycled, it may still be using 1.8V
	 * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
	 * transfer mode.
	 */
	if (!v18_fixup_failed && !mmc_host_is_spi(host) && mmc_host_uhs(host) &&
	    mmc_sd_card_using_v18(card) &&
	    host->ios.signal_voltage != MMC_SIGNAL_VOLTAGE_180) {
		/*
		 * Re-read switch information in case it has changed since
		 * oldcard was initialized.
		 */
		if (oldcard) {
			err = mmc_read_switch(card);
			if (err)
				goto free_card;
		}
		if (mmc_sd_card_using_v18(card)) {
			if (mmc_host_set_uhs_voltage(host) ||
			    mmc_sd_init_uhs_card(card)) {
				v18_fixup_failed = true;
				mmc_power_cycle(host, ocr);
				if (!oldcard)
					mmc_remove_card(card);
				goto retry;
			}
			goto done;
		}
	}

	/* Initialization sequence for UHS-I cards */
	if (rocr & SD_ROCR_S18A && mmc_host_uhs(host)) {
		err = mmc_sd_init_uhs_card(card);
		if (err)
			goto free_card;
	} else {
		/*
		 * Attempt to change to high-speed (if supported)
		 */
		err = mmc_sd_switch_hs(card);
		if (err > 0)
			mmc_set_timing(card->host, MMC_TIMING_SD_HS);
		else if (err)
			goto free_card;

		/*
		 * Set bus speed.
		 */
		mmc_set_clock(host, mmc_sd_get_max_clock(card));

		/*
		 * Switch to wider bus (if supported).
		 */
		if ((host->caps & MMC_CAP_4_BIT_DATA) &&
			(card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
			err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4);
			if (err)
				goto free_card;

			mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
		}
	}

	if (!oldcard) {
		/* Read/parse the extension registers. */
		err = sd_read_ext_regs(card);
		if (err)
			goto free_card;
	}

	/* Enable internal SD cache if supported. */
	if (card->ext_perf.feature_support & SD_EXT_PERF_CACHE) {
		err = sd_enable_cache(card);
		if (err)
			goto free_card;
	}

	if (host->cqe_ops && !host->cqe_enabled) {
		err = host->cqe_ops->cqe_enable(host, card);
		if (!err) {
			host->cqe_enabled = true;
			host->hsq_enabled = true;
			pr_info("%s: Host Software Queue enabled\n",
				mmc_hostname(host));
		}
	}

	if (host->caps2 & MMC_CAP2_AVOID_3_3V &&
	    host->ios.signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
		pr_err("%s: Host failed to negotiate down from 3.3V\n",
			mmc_hostname(host));
		err = -EINVAL;
		goto free_card;
	}
done:
	host->card = card;
	return 0;

free_card:
	if (!oldcard)
		mmc_remove_card(card);

	return err;
}