Commit f4b7f927 authored by Haavard Skinnemoen's avatar Haavard Skinnemoen Committed by Pierre Ossman
Browse files

mmc: Add per-card debugfs support 



For each card successfully added to the bus, create a subdirectory under
the host's debugfs root with information about the card.

At the moment, only a single file is added to the card directory for
all cards: "state". It reflects the "state" field in struct mmc_card,
indicating whether the card is present, readonly, etc.

For MMC and SD cards (not SDIO), another file is added: "status".
Reading this file will ask the card about its current status and
return it. This can be useful if the card just refuses to respond to
any commands, which might indicate that the card state is not what the
MMC core thinks it is (due to a missing stop command, for example.)

Signed-off-by: default avatarHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
parent 6edd8ee6

drivers/mmc/core/bus.c

+8 −0
Original line number Diff line number Diff line
@@ -252,6 +252,10 @@ int mmc_add_card(struct mmc_card *card) 
	if (ret)

		return ret;



#ifdef CONFIG_DEBUG_FS

	mmc_add_card_debugfs(card);

#endif



	mmc_card_set_present(card);



	return 0;
@@ -263,6 +267,10 @@ int mmc_add_card(struct mmc_card *card) 
 */

void mmc_remove_card(struct mmc_card *card)

{

#ifdef CONFIG_DEBUG_FS

	mmc_remove_card_debugfs(card);

#endif



	if (mmc_card_present(card)) {

		if (mmc_host_is_spi(card->host)) {

			printk(KERN_INFO "%s: SPI card removed\n",

drivers/mmc/core/core.h

+3 −0
Original line number Diff line number Diff line
@@ -56,5 +56,8 @@ extern int use_spi_crc; 
void mmc_add_host_debugfs(struct mmc_host *host);

void mmc_remove_host_debugfs(struct mmc_host *host);



void mmc_add_card_debugfs(struct mmc_card *card);

void mmc_remove_card_debugfs(struct mmc_card *card);



#endif

drivers/mmc/core/debugfs.c

+61 −0
Original line number Diff line number Diff line
@@ -12,9 +12,11 @@ 
#include <linux/seq_file.h>

#include <linux/stat.h>



#include <linux/mmc/card.h>

#include <linux/mmc/host.h>



#include "core.h"

#include "mmc_ops.h"



/* The debugfs functions are optimized away when CONFIG_DEBUG_FS isn't set. */

static int mmc_ios_show(struct seq_file *s, void *data)
@@ -162,3 +164,62 @@ void mmc_remove_host_debugfs(struct mmc_host *host) 
{

	debugfs_remove_recursive(host->debugfs_root);

}



static int mmc_dbg_card_status_get(void *data, u64 *val)

{

	struct mmc_card	*card = data;

	u32		status;

	int		ret;



	mmc_claim_host(card->host);



	ret = mmc_send_status(data, &status);

	if (!ret)

		*val = status;



	mmc_release_host(card->host);



	return ret;

}

DEFINE_SIMPLE_ATTRIBUTE(mmc_dbg_card_status_fops, mmc_dbg_card_status_get,

		NULL, "%08llx\n");



void mmc_add_card_debugfs(struct mmc_card *card)

{

	struct mmc_host	*host = card->host;

	struct dentry	*root;



	if (!host->debugfs_root)

		return;



	root = debugfs_create_dir(mmc_card_id(card), host->debugfs_root);

	if (IS_ERR(root))

		/* Don't complain -- debugfs just isn't enabled */

		return;

	if (!root)

		/* Complain -- debugfs is enabled, but it failed to

		 * create the directory. */

		goto err;



	card->debugfs_root = root;



	if (!debugfs_create_x32("state", S_IRUSR, root, &card->state))

		goto err;



	if (mmc_card_mmc(card) || mmc_card_sd(card))

		if (!debugfs_create_file("status", S_IRUSR, root, card,

					&mmc_dbg_card_status_fops))

			goto err;



	return;



err:

	debugfs_remove_recursive(root);

	card->debugfs_root = NULL;

	dev_err(&card->dev, "failed to initialize debugfs\n");

}



void mmc_remove_card_debugfs(struct mmc_card *card)

{

	debugfs_remove_recursive(card->debugfs_root);

}

include/linux/mmc/card.h

+2 −0
Original line number Diff line number Diff line
@@ -111,6 +111,8 @@ struct mmc_card { 
	unsigned		num_info;	/* number of info strings */

	const char		**info;		/* info strings */

	struct sdio_func_tuple	*tuples;	/* unknown common tuples */



	struct dentry		*debugfs_root;

};



#define mmc_card_mmc(c)		((c)->type == MMC_TYPE_MMC)

CRA Git | Maintained and supported by SUSTech CRA and CCSE