pcmcia: add new CIS access helpers

As a replacement to pcmcia_get_{first,next}_tuple() and
pcmcia_get_tuple_data(), three new -- and easier to use --
functions are added:

- pcmcia_get_tuple() to get the very first CIS entry of one
  type.

- pcmcia_loop_tuple() to loop over all CIS entries of one type.

- pcmcia_get_mac_from_cis() to read out the hardware MAC address
  from CISTPL_FUNCE.

Only a handful of drivers need these functions anyway, as most
CIS access is already handled by pcmcia_loop_config(), which
now shares the same backed (pccard_loop_tuple()) with
pcmcia_loop_tuple().

A pcmcia_get_mac_from_cis() bug noted by Komuro
<komurojun-mbn@nifty.com> has been fixed in this revision.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

1 files changed, 185 insertions, 32 deletions

diff --git a/drivers/pcmcia/pcmcia_resource.c b/drivers/pcmcia/pcmcia_resource.c
index d919e96c0afd..0bfb05aa8f85 100644
--- a/drivers/pcmcia/pcmcia_resource.c
+++ b/drivers/pcmcia/pcmcia_resource.c
@@ -20,6 +20,7 @@
 #include <linux/delay.h>
 #include <linux/pci.h>
 #include <linux/device.h>
+#include <linux/netdevice.h>
 
 #include <pcmcia/cs_types.h>
 #include <pcmcia/ss.h>
@@ -885,13 +886,40 @@ EXPORT_SYMBOL(pcmcia_disable_device);
 
 
 struct pcmcia_cfg_mem {
-        tuple_t tuple;
+        struct pcmcia_device *p_dev;
+        void *priv_data;
+        int (*conf_check) (struct pcmcia_device *p_dev,
+                           cistpl_cftable_entry_t *cfg,
+                           cistpl_cftable_entry_t *dflt,
+                           unsigned int vcc,
+                           void *priv_data);
         cisparse_t parse;
-        u8 buf[256];
         cistpl_cftable_entry_t dflt;
 };
 
 /**
+ * pcmcia_do_loop_config() - internal helper for pcmcia_loop_config()
+ *
+ * pcmcia_do_loop_config() is the internal callback for the call from
+ * pcmcia_loop_config() to pccard_loop_tuple(). Data is transferred
+ * by a struct pcmcia_cfg_mem.
+ */
+static int pcmcia_do_loop_config(tuple_t *tuple, cisparse_t *parse, void *priv)
+{
+        cistpl_cftable_entry_t *cfg = &parse->cftable_entry;
+        struct pcmcia_cfg_mem *cfg_mem = priv;
+
+        /* default values */
+        cfg_mem->p_dev->conf.ConfigIndex = cfg->index;
+        if (cfg->flags & CISTPL_CFTABLE_DEFAULT)
+                cfg_mem->dflt = *cfg;
+
+        return cfg_mem->conf_check(cfg_mem->p_dev, cfg, &cfg_mem->dflt,
+                                   cfg_mem->p_dev->socket->socket.Vcc,
+                                   cfg_mem->priv_data);
+}
+
+/**
  * pcmcia_loop_config() - loop over configuration options
  * @p_dev:      the struct pcmcia_device which we need to loop for.
  * @conf_check: function to call for each configuration option.
@@ -913,48 +941,173 @@ int pcmcia_loop_config(struct pcmcia_device *p_dev,
                        void *priv_data)
 {
         struct pcmcia_cfg_mem *cfg_mem;
-
-        tuple_t *tuple;
         int ret;
-        unsigned int vcc;
 
         cfg_mem = kzalloc(sizeof(struct pcmcia_cfg_mem), GFP_KERNEL);
         if (cfg_mem == NULL)
                 return -ENOMEM;
 
-        /* get the current Vcc setting */
-        vcc = p_dev->socket->socket.Vcc;
+        cfg_mem->p_dev = p_dev;
+        cfg_mem->conf_check = conf_check;
+        cfg_mem->priv_data = priv_data;
 
-        tuple = &cfg_mem->tuple;
-        tuple->TupleData = cfg_mem->buf;
-        tuple->TupleDataMax = 255;
-        tuple->TupleOffset = 0;
-        tuple->DesiredTuple = CISTPL_CFTABLE_ENTRY;
-        tuple->Attributes = 0;
+        ret = pccard_loop_tuple(p_dev->socket, p_dev->func,
+                                CISTPL_CFTABLE_ENTRY, &cfg_mem->parse,
+                                cfg_mem, pcmcia_do_loop_config);
 
-        ret = pcmcia_get_first_tuple(p_dev, tuple);
-        while (!ret) {
-                cistpl_cftable_entry_t *cfg = &cfg_mem->parse.cftable_entry;
+        kfree(cfg_mem);
+        return ret;
+}
+EXPORT_SYMBOL(pcmcia_loop_config);
 
-                if (pcmcia_get_tuple_data(p_dev, tuple))
-                        goto next_entry;
 
-                if (pcmcia_parse_tuple(tuple, &cfg_mem->parse))
-                        goto next_entry;
+struct pcmcia_loop_mem {
+        struct pcmcia_device *p_dev;
+        void *priv_data;
+        int (*loop_tuple) (struct pcmcia_device *p_dev,
+                           tuple_t *tuple,
+                           void *priv_data);
+};
 
-                /* default values */
-                p_dev->conf.ConfigIndex = cfg->index;
-                if (cfg->flags & CISTPL_CFTABLE_DEFAULT)
-                        cfg_mem->dflt = *cfg;
+/**
+ * pcmcia_do_loop_tuple() - internal helper for pcmcia_loop_config()
+ *
+ * pcmcia_do_loop_tuple() is the internal callback for the call from
+ * pcmcia_loop_tuple() to pccard_loop_tuple(). Data is transferred
+ * by a struct pcmcia_cfg_mem.
+ */
+static int pcmcia_do_loop_tuple(tuple_t *tuple, cisparse_t *parse, void *priv)
+{
+        struct pcmcia_loop_mem *loop = priv;
 
-                ret = conf_check(p_dev, cfg, &cfg_mem->dflt, vcc, priv_data);
-                if (!ret)
-                        break;
+        return loop->loop_tuple(loop->p_dev, tuple, loop->priv_data);
+};
+
+/**
+ * pcmcia_loop_tuple() - loop over tuples in the CIS
+ * @p_dev:      the struct pcmcia_device which we need to loop for.
+ * @code:       which CIS code shall we look for?
+ * @priv_data:  private data to be passed to the loop_tuple function.
+ * @loop_tuple: function to call for each CIS entry of type @function. IT
+ *              gets passed the raw tuple and @priv_data.
+ *
+ * pcmcia_loop_tuple() loops over all CIS entries of type @function, and
+ * calls the @loop_tuple function for each entry. If the call to @loop_tuple
+ * returns 0, the loop exits. Returns 0 on success or errorcode otherwise.
+ */
+int pcmcia_loop_tuple(struct pcmcia_device *p_dev, cisdata_t code,
+                      int (*loop_tuple) (struct pcmcia_device *p_dev,
+                                         tuple_t *tuple,
+                                         void *priv_data),
+                      void *priv_data)
+{
+        struct pcmcia_loop_mem loop = {
+                .p_dev = p_dev,
+                .loop_tuple = loop_tuple,
+                .priv_data = priv_data};
+
+        return pccard_loop_tuple(p_dev->socket, p_dev->func, code, NULL,
+                                 &loop, pcmcia_do_loop_tuple);
+};
+EXPORT_SYMBOL(pcmcia_loop_tuple);
 
-next_entry:
-                ret = pcmcia_get_next_tuple(p_dev, tuple);
+
+struct pcmcia_loop_get {
+        size_t len;
+        cisdata_t **buf;
+};
+
+/**
+ * pcmcia_do_get_tuple() - internal helper for pcmcia_get_tuple()
+ *
+ * pcmcia_do_get_tuple() is the internal callback for the call from
+ * pcmcia_get_tuple() to pcmcia_loop_tuple(). As we're only interested in
+ * the first tuple, return 0 unconditionally. Create a memory buffer large
+ * enough to hold the content of the tuple, and fill it with the tuple data.
+ * The caller is responsible to free the buffer.
+ */
+static int pcmcia_do_get_tuple(struct pcmcia_device *p_dev, tuple_t *tuple,
+                               void *priv)
+{
+        struct pcmcia_loop_get *get = priv;
+
+        *get->buf = kzalloc(tuple->TupleDataLen, GFP_KERNEL);
+        if (*get->buf) {
+                get->len = tuple->TupleDataLen;
+                memcpy(*get->buf, tuple->TupleData, tuple->TupleDataLen);
         }
+        return 0;
+};
+
+/**
+ * pcmcia_get_tuple() - get first tuple from CIS
+ * @p_dev:      the struct pcmcia_device which we need to loop for.
+ * @code:       which CIS code shall we look for?
+ * @buf:        pointer to store the buffer to.
+ *
+ * pcmcia_get_tuple() gets the content of the first CIS entry of type @code.
+ * It returns the buffer length (or zero). The caller is responsible to free
+ * the buffer passed in @buf.
+ */
+size_t pcmcia_get_tuple(struct pcmcia_device *p_dev, cisdata_t code,
+                        unsigned char **buf)
+{
+        struct pcmcia_loop_get get = {
+                .len = 0,
+                .buf = buf,
+        };
+
+        *get.buf = NULL;
+        pcmcia_loop_tuple(p_dev, code, pcmcia_do_get_tuple, &get);
+
+        return get.len;
+};
+EXPORT_SYMBOL(pcmcia_get_tuple);
+
+
+/**
+ * pcmcia_do_get_mac() - internal helper for pcmcia_get_mac_from_cis()
+ *
+ * pcmcia_do_get_mac() is the internal callback for the call from
+ * pcmcia_get_mac_from_cis() to pcmcia_loop_tuple(). We check whether the
+ * tuple contains a proper LAN_NODE_ID of length 6, and copy the data
+ * to struct net_device->dev_addr[i].
+ */
+static int pcmcia_do_get_mac(struct pcmcia_device *p_dev, tuple_t *tuple,
+                             void *priv)
+{
+        struct net_device *dev = priv;
+        int i;
+
+        if (tuple->TupleData[0] != CISTPL_FUNCE_LAN_NODE_ID)
+                return -EINVAL;
+        if (tuple->TupleDataLen < ETH_ALEN + 2) {
+                dev_warn(&p_dev->dev, "Invalid CIS tuple length for "
+                        "LAN_NODE_ID\n");
+                return -EINVAL;
+        }
+
+        if (tuple->TupleData[1] != ETH_ALEN) {
+                dev_warn(&p_dev->dev, "Invalid header for LAN_NODE_ID\n");
+                return -EINVAL;
+        }
+        for (i = 0; i < 6; i++)
+                dev->dev_addr[i] = tuple->TupleData[i+2];
+        return 0;
+};
+
+/**
+ * pcmcia_get_mac_from_cis() - read out MAC address from CISTPL_FUNCE
+ * @p_dev:      the struct pcmcia_device for which we want the address.
+ * @dev:        a properly prepared struct net_device to store the info to.
+ *
+ * pcmcia_get_mac_from_cis() reads out the hardware MAC address from
+ * CISTPL_FUNCE and stores it into struct net_device *dev->dev_addr which
+ * must be set up properly by the driver (see examples!).
+ */
+int pcmcia_get_mac_from_cis(struct pcmcia_device *p_dev, struct net_device *dev)
+{
+        return pcmcia_loop_tuple(p_dev, CISTPL_FUNCE, pcmcia_do_get_mac, dev);
+};
+EXPORT_SYMBOL(pcmcia_get_mac_from_cis);
 
-        return ret;
-}
-EXPORT_SYMBOL(pcmcia_loop_config);