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sd: add stub for SDIO support

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Add stub code for SDIO support, capable of verifying card responds to CMD5.
This commit also changes the architecture of the SDIO probe step to make
adding new protocol support more streamlined, and enable compiling out
support for undesired protocols.

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>
This commit is contained in:
Daniel DeGrasse 2022-05-24 11:35:06 -05:00 • committed by Carles Cufí
commit b7cd970493
8 changed files with 152 additions and 149 deletions
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78
subsys/sd/sdio.c Normal file
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/*
* Copyright 2022 NXP
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/zephyr.h>
#include <zephyr/drivers/sdhc.h>
#include <zephyr/sd/sd.h>
#include <zephyr/sd/sdmmc.h>
#include <zephyr/sd/sd_spec.h>
#include <zephyr/logging/log.h>
#include "sd_utils.h"
LOG_MODULE_DECLARE(sd, CONFIG_SD_LOG_LEVEL);
/*
* Send SDIO OCR using CMD5
*/
int sdio_send_ocr(struct sd_card *card, uint32_t ocr)
{
struct sdhc_command cmd = {0};
int ret;
int retries;
cmd.opcode = SDIO_SEND_OP_COND;
cmd.arg = ocr;
cmd.response_type = (SD_RSP_TYPE_R4 | SD_SPI_RSP_TYPE_R4);
cmd.timeout_ms = CONFIG_SD_CMD_TIMEOUT;
/* Send OCR5 to initialize card */
for (retries = 0; retries < CONFIG_SD_OCR_RETRY_COUNT; retries++) {
ret = sdhc_request(card->sdhc, &cmd, NULL);
if (ret) {
if (ocr == 0) {
/* Just probing card, likely not SDIO */
return SD_NOT_SDIO;
}
return ret;
}
if (ocr == 0) {
/* We are probing card, check number of IO functions */
card->num_io = (cmd.response[0] & SDIO_OCR_IO_NUMBER)
>> SDIO_OCR_IO_NUMBER_SHIFT;
if ((card->num_io == 0) ||
((cmd.response[0] & SDIO_IO_OCR_MASK) == 0)) {
if (cmd.response[0] & SDIO_OCR_MEM_PRESENT_FLAG) {
/* Card is not an SDIO card */
return SD_NOT_SDIO;
}
/* Card is not a supported SD device */
return -ENOTSUP;
}
/* Card has IO present, return zero to
* indicate SDIO card
*/
return 0;
}
}
}
/*
* Initialize an SDIO card for use with subsystem
*/
int sdio_card_init(struct sd_card *card)
{
int ret;
/* Probe card with SDIO OCR CM5 */
ret = sdio_send_ocr(card, 0);
if (ret) {
return ret;
}
/* Card responded to ACMD41, type is SDIO */
card->type = CARD_SDIO;
/* No support for SDIO */
return -ENOTSUP;
}