[patch 3/5] [RFC] Add MMC Password Protection (lock/unlock) support V7: mmc_lock_unlock.diff

Anderson Briglia
2006-11-22T15:58:55Z

Implement card lock/unlock operation, using the MMC_LOCK_UNLOCK command.

Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Anderson Lizardo <anderson.lizardo <at> indt.org.br>
Signed-off-by: Anderson Briglia <anderson.briglia <at> indt.org.br>

Index: linux-omap-2.6.git/drivers/mmc/mmc.c
===================================================================
--- linux-omap-2.6.git.orig/drivers/mmc/mmc.c 2006-11-22 09:19:27.000000000 -0400
+++ linux-omap-2.6.git/drivers/mmc/mmc.c 2006-11-22 09:56:13.000000000 -0400
@@ -4,6 +4,8 @@
* Copyright (C) 2003-2004 Russell King, All Rights Reserved.
* SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
* SD support Copyright (C) 2005 Pierre Ossman, All Rights Reserved.
+ * MMC password protection (C) 2006 Instituto Nokia de Tecnologia (INdT),
+ * All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@@ -19,6 +21,7 @@
#include <linux/err.h>
#include <asm/scatterlist.h>
#include <linux/scatterlist.h>
+#include <linux/key.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -1159,6 +1162,122 @@ static void mmc_setup(struct mmc_host *h
mmc_read_scrs(host);
}

+/**
+ * mmc_lock_unlock - send LOCK_UNLOCK command to a specific card.
+ * @card: card to which the LOCK_UNLOCK command should be sent
+ * @key: key containing the MMC password
+ * @mode: LOCK_UNLOCK mode
+ *
+ */
+int mmc_lock_unlock(struct mmc_card *card, struct key *key, int mode)
+{
+ struct mmc_request mrq;
+ struct mmc_command cmd;
+ struct mmc_data data;
+ struct scatterlist sg;
+ struct mmc_key_payload *mpayload;
+ unsigned long erase_timeout;
+ int err, data_size;
+ u8 *data_buf;
+
+ mpayload = NULL;
+ data_size = 1;
+ if (mode != MMC_LOCK_MODE_ERASE) {
+ mpayload = rcu_dereference(key->payload.data);
+ data_size = 2 + mpayload->datalen;
+ }
+
+ data_buf = kmalloc(data_size, GFP_KERNEL);
+ if (!data_buf)
+ return -ENOMEM;
+ memset(data_buf, 0, data_size);
+
+ data_buf[0] = mode;
+ if (mode != MMC_LOCK_MODE_ERASE) {
+ data_buf[1] = mpayload->datalen;
+ memcpy(data_buf + 2, mpayload->data, mpayload->datalen);
+ }
+
+ err = mmc_card_claim_host(card);
+ if (err != MMC_ERR_NONE)
+ goto out;
+
+ memset(&cmd, 0, sizeof(struct mmc_command));
+
+ cmd.opcode = MMC_SET_BLOCKLEN;
+ cmd.arg = data_size;
+ cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+ err = mmc_wait_for_cmd(card->host, &cmd, CMD_RETRIES);
+ if (err != MMC_ERR_NONE)
+ goto error;
+
+ memset(&cmd, 0, sizeof(struct mmc_command));
+
+ cmd.opcode = MMC_LOCK_UNLOCK;
+ cmd.arg = 0;
+ cmd.flags = MMC_RSP_R1B | MMC_CMD_ADTC;
+
+ memset(&data, 0, sizeof(struct mmc_data));
+
+ mmc_set_data_timeout(&data, card, 1);
+
+ data.blksz = data_size;
+ data.blocks = 1;
+ data.flags = MMC_DATA_WRITE;
+ data.sg = &sg;
+ data.sg_len = 1;
+
+ memset(&mrq, 0, sizeof(struct mmc_request));
+
+ mrq.cmd = &cmd;
+ mrq.data = &data;
+
+ sg_init_one(&sg, data_buf, data_size);
+ err = mmc_wait_for_req(card->host, &mrq);
+ if (err != MMC_ERR_NONE)
+ goto error;
+
+ memset(&cmd, 0, sizeof(struct mmc_command));
+
+ cmd.opcode = MMC_SEND_STATUS;
+ cmd.arg = card->rca << 16;
+ cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+
+ /* set timeout for forced erase operation to 3 min. (see MMC spec) */
+ erase_timeout = jiffies + 180 * HZ;
+ do {
+ /* we cannot use "retries" here because the
+ * R1_LOCK_UNLOCK_FAILED bit is cleared by subsequent reads to
+ * the status register, hiding the error condition */
+ err = mmc_wait_for_cmd(card->host, &cmd, 0);
+ if (err != MMC_ERR_NONE)
+ break;
+ /* the other modes don't need timeout checking */
+ if (mode != MMC_LOCK_MODE_ERASE)
+ continue;
+ if (time_after(jiffies, erase_timeout)) {
+ dev_dbg(&card->dev, "forced erase timed out\n");
+ err = MMC_ERR_TIMEOUT;
+ break;
+ }
+ } while (!(cmd.resp[0] & R1_READY_FOR_DATA));
+ if (cmd.resp[0] & R1_LOCK_UNLOCK_FAILED) {
+ dev_dbg(&card->dev, "LOCK_UNLOCK operation failed\n");
+ err = MMC_ERR_FAILED;
+ }
+
+ if (cmd.resp[0] & R1_CARD_IS_LOCKED)
+ mmc_card_set_locked(card);
+ else
+ mmc_card_clear_locked(card);
+
+error:
+ mmc_card_release_host(card);
+out:
+ kfree(data_buf);
+
+ return err;
+}

/**
* mmc_detect_change - process change of state on a MMC socket
Index: linux-omap-2.6.git/drivers/mmc/mmc.h
===================================================================
--- linux-omap-2.6.git.orig/drivers/mmc/mmc.h 2006-11-22 09:19:27.000000000 -0400
+++ linux-omap-2.6.git/drivers/mmc/mmc.h 2006-11-22 09:19:27.000000000 -0400
@@ -27,6 +27,10 @@ struct mmc_key_payload {
char data[0]; /* actual data */
};

+struct key;
+
+extern int mmc_lock_unlock(struct mmc_card *card, struct key *key, int mode);
+
int mmc_schedule_work(struct work_struct *work);
int mmc_schedule_delayed_work(struct work_struct *work, unsigned long delay);
void mmc_flush_scheduled_work(void);
Index: linux-omap-2.6.git/include/linux/mmc/protocol.h
===================================================================
--- linux-omap-2.6.git.orig/include/linux/mmc/protocol.h 2006-11-22 09:19:13.000000000 -0400
+++ linux-omap-2.6.git/include/linux/mmc/protocol.h 2006-11-22 09:19:27.000000000 -0400
@@ -244,5 +244,13 @@ struct _mmc_csd {
#define SD_BUS_WIDTH_1 0
#define SD_BUS_WIDTH_4 2

+/*
+ * MMC_LOCK_UNLOCK modes
+ */
+#define MMC_LOCK_MODE_ERASE (1<<3)
+#define MMC_LOCK_MODE_UNLOCK (0<<2)
+#define MMC_LOCK_MODE_CLR_PWD (1<<1)
+#define MMC_LOCK_MODE_SET_PWD (1<<0)
+
#endif /* MMC_MMC_PROTOCOL_H */