sdio: rework cis tuple parsing

Rework the current CIS tuple parsing code, reusing the existing
infrastructure and providing an easy way to add new CISTPL_FUNCE parsers
by TPLFE_TYPE.

Valid known CIS tuples are now silently queued for the SDIO function
driver when not parsed/processed (-EILSEQ) by the SDIO core.  Unknown CIS
tuples (-ENOENT) are queued too for the SDIO function driver without
aborting the initialization, but emit a warning in the kernel log.

CISTPL_FUNCE tuples can be "whitelisted" now by adding a matching entry to
the cis_tpl_funce_list table.

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Acked-by: Pierre Ossman <pierre@ossman.eu>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 93 insertions, 74 deletions

diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index f85dcd536508..9538389783c1 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -97,26 +97,56 @@ static const unsigned char speed_val[16] =
 static const unsigned int speed_unit[8] =
         { 10000, 100000, 1000000, 10000000, 0, 0, 0, 0 };
 
-/* FUNCE tuples with these types get passed to SDIO drivers */
-static const unsigned char funce_type_whitelist[] = {
-        4 /* CISTPL_FUNCE_LAN_NODE_ID used in Broadcom cards */
+
+typedef int (tpl_parse_t)(struct mmc_card *, struct sdio_func *,
+                           const unsigned char *, unsigned);
+
+struct cis_tpl {
+        unsigned char code;
+        unsigned char min_size;
+        tpl_parse_t *parse;
 };
 
-static int cistpl_funce_whitelisted(unsigned char type)
+static int cis_tpl_parse(struct mmc_card *card, struct sdio_func *func,
+                         const char *tpl_descr,
+                         const struct cis_tpl *tpl, int tpl_count,
+                         unsigned char code,
+                         const unsigned char *buf, unsigned size)
 {
-        int i;
+        int i, ret;
 
-        for (i = 0; i < ARRAY_SIZE(funce_type_whitelist); i++) {
-                if (funce_type_whitelist[i] == type)
-                        return 1;
+        /* look for a matching code in the table */
+        for (i = 0; i < tpl_count; i++, tpl++) {
+                if (tpl->code == code)
+                        break;
         }
-        return 0;
+        if (i < tpl_count) {
+                if (size >= tpl->min_size) {
+                        if (tpl->parse)
+                                ret = tpl->parse(card, func, buf, size);
+                        else
+                                ret = -EILSEQ;  /* known tuple, not parsed */
+                } else {
+                        /* invalid tuple */
+                        ret = -EINVAL;
+                }
+                if (ret && ret != -EILSEQ && ret != -ENOENT) {
+                        printk(KERN_ERR "%s: bad %s tuple 0x%02x (%u bytes)\n",
+                               mmc_hostname(card->host), tpl_descr, code, size);
+                }
+        } else {
+                /* unknown tuple */
+                ret = -ENOENT;
+        }
+
+        return ret;
 }
 
-static int cistpl_funce_common(struct mmc_card *card,
+static int cistpl_funce_common(struct mmc_card *card, struct sdio_func *func,
                                const unsigned char *buf, unsigned size)
 {
-        if (size < 0x04 || buf[0] != 0)
+        /* Only valid for the common CIS (function 0) */
+        if (func)
                 return -EINVAL;
 
         /* TPLFE_FN0_BLK_SIZE */
@@ -129,20 +159,24 @@ static int cistpl_funce_common(struct mmc_card *card,
         return 0;
 }
 
-static int cistpl_funce_func(struct sdio_func *func,
+static int cistpl_funce_func(struct mmc_card *card, struct sdio_func *func,
                              const unsigned char *buf, unsigned size)
 {
         unsigned vsn;
         unsigned min_size;
 
-        /* let SDIO drivers take care of whitelisted FUNCE tuples */
-        if (cistpl_funce_whitelisted(buf[0]))
-                return -EILSEQ;
+        /* Only valid for the individual function's CIS (1-7) */
+        if (!func)
+                return -EINVAL;
 
+        /*
+         * This tuple has a different length depending on the SDIO spec
+         * version.
+         */
         vsn = func->card->cccr.sdio_vsn;
         min_size = (vsn == SDIO_SDIO_REV_1_00) ? 28 : 42;
 
-        if (size < min_size || buf[0] != 1)
+        if (size < min_size)
                 return -EINVAL;
 
         /* TPLFE_MAX_BLK_SIZE */
@@ -157,39 +191,32 @@ static int cistpl_funce_func(struct sdio_func *func,
         return 0;
 }
 
+/*
+ * Known TPLFE_TYPEs table for CISTPL_FUNCE tuples.
+ *
+ * Note that, unlike PCMCIA, CISTPL_FUNCE tuples are not parsed depending
+ * on the TPLFID_FUNCTION value of the previous CISTPL_FUNCID as on SDIO
+ * TPLFID_FUNCTION is always hardcoded to 0x0C.
+ */
+static const struct cis_tpl cis_tpl_funce_list[] = {
+        {       0x00,   4,      cistpl_funce_common             },
+        {       0x01,   0,      cistpl_funce_func               },
+        {       0x04,   1+1+6,  /* CISTPL_FUNCE_LAN_NODE_ID */  },
+};
+
 static int cistpl_funce(struct mmc_card *card, struct sdio_func *func,
                         const unsigned char *buf, unsigned size)
 {
-        int ret;
-
-        /*
-         * There should be two versions of the CISTPL_FUNCE tuple,
-         * one for the common CIS (function 0) and a version used by
-         * the individual function's CIS (1-7). Yet, the later has a
-         * different length depending on the SDIO spec version.
-         */
-        if (func)
-                ret = cistpl_funce_func(func, buf, size);
-        else
-                ret = cistpl_funce_common(card, buf, size);
-
-        if (ret && ret != -EILSEQ) {
-                printk(KERN_ERR "%s: bad CISTPL_FUNCE size %u "
-                       "type %u\n", mmc_hostname(card->host), size, buf[0]);
-        }
+        if (size < 1)
+                return -EINVAL;
 
-        return ret;
+        return cis_tpl_parse(card, func, "CISTPL_FUNCE",
+                             cis_tpl_funce_list,
+                             ARRAY_SIZE(cis_tpl_funce_list),
+                             buf[0], buf, size);
 }
 
-typedef int (tpl_parse_t)(struct mmc_card *, struct sdio_func *,
-                           const unsigned char *, unsigned);
-
-struct cis_tpl {
-        unsigned char code;
-        unsigned char min_size;
-        tpl_parse_t *parse;
-};
-
+/* Known TPL_CODEs table for CIS tuples */
 static const struct cis_tpl cis_tpl_list[] = {
         {       0x15,   3,      cistpl_vers_1           },
         {       0x20,   4,      cistpl_manfid           },
@@ -268,46 +295,38 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
                         break;
                 }
 
-                for (i = 0; i < ARRAY_SIZE(cis_tpl_list); i++)
-                        if (cis_tpl_list[i].code == tpl_code)
-                                break;
-                if (i < ARRAY_SIZE(cis_tpl_list)) {
-                        const struct cis_tpl *tpl = cis_tpl_list + i;
-                        if (tpl_link < tpl->min_size) {
-                                printk(KERN_ERR
-                                       "%s: bad CIS tuple 0x%02x"
-                                       " (length = %u, expected >= %u)\n",
-                                       mmc_hostname(card->host),
-                                       tpl_code, tpl_link, tpl->min_size);
-                                ret = -EINVAL;
-                        } else if (tpl->parse) {
-                                ret = tpl->parse(card, func,
-                                                 this->data, tpl_link);
-                        }
+                /* Try to parse the CIS tuple */
+                ret = cis_tpl_parse(card, func, "CIS",
+                                    cis_tpl_list, ARRAY_SIZE(cis_tpl_list),
+                                    tpl_code, this->data, tpl_link);
+                if (ret == -EILSEQ || ret == -ENOENT) {
                         /*
-                         * We don't need the tuple anymore if it was
-                         * successfully parsed by the SDIO core or if it is
-                         * not going to be parsed by SDIO drivers.
+                         * The tuple is unknown or known but not parsed.
+                         * Queue the tuple for the function driver.
                          */
-                        if (!ret || ret != -EILSEQ)
-                                kfree(this);
-                } else {
-                        /* unknown tuple */
-                        ret = -EILSEQ;
-                }
-
-                if (ret == -EILSEQ) {
-                        /* this tuple is unknown to the core or whitelisted */
                         this->next = NULL;
                         this->code = tpl_code;
                         this->size = tpl_link;
                         *prev = this;
                         prev = &this->next;
-                        printk(KERN_DEBUG
-                               "%s: queuing CIS tuple 0x%02x length %u\n",
-                               mmc_hostname(card->host), tpl_code, tpl_link);
+
+                        if (ret == -ENOENT) {
+                                /* warn about unknown tuples */
+                                printk(KERN_WARNING "%s: queuing unknown"
+                                       " CIS tuple 0x%02x (%u bytes)\n",
+                                       mmc_hostname(card->host),
+                                       tpl_code, tpl_link);
+                        }
+
                         /* keep on analyzing tuples */
                         ret = 0;
+                } else {
+                        /*
+                         * We don't need the tuple anymore if it was
+                         * successfully parsed by the SDIO core or if it is
+                         * not going to be queued for a driver.
+                         */
+                        kfree(this);
                 }
 
                 ptr += tpl_link;