ssb: sprom: add dev_id field for value overriding standard ID

Some devices may have different features despite sharing the same ID (e.g. PCI ID). For example 14e4:4331 is usually a dual band, but this can be "limited". Device with "pci/x/y/devid=0x4332" supports 2.4 GHz only. Similarly 0x4333 will mean support for 5 GHz only.
Add entry in SPROM so info described above can be extracted and stored.

Signed-off-by Rafa? Mi?ecki <[email protected]>

---
I managed to find "devid" on every common SPROM rev:
pci/1/1/sromrev=2
pci/1/1/devid=0x4318

pci/1/1/sromrev=4
pci/1/1/devid=0x4329

pci/1/1/sromrev=8
pci/1/1/devid=0x432d

pci/1/1/sromrev=9
pci/1/1/devid=0x4332

pci/1/1/sromrev=11
pci/1/1/devid=0x43a1

So it makes the most sense to always try to extract it.

---
 arch/mips/bcm47xx/sprom.c | 1 +
 include/linux/ssb/ssb.h   | 1 +
 2 files changed, 2 insertions(+)

arch/mips/bcm47xx/sprom.c +1 -0

index a8b5408..da4cdb1 100644
@@ -168,6 +168,7 @@ static void nvram_read_alpha2(const char *prefix, const char *name,
 static void bcm47xx_fill_sprom_r1234589(struct ssb_sprom *sprom,
 					const char *prefix, bool fallback)
 {
+	nvram_read_u16(prefix, NULL, "devid", &sprom->dev_id, 0, fallback);
 	nvram_read_u8(prefix, NULL, "ledbh0", &sprom->gpio0, 0xff, fallback);
 	nvram_read_u8(prefix, NULL, "ledbh1", &sprom->gpio1, 0xff, fallback);
 	nvram_read_u8(prefix, NULL, "ledbh2", &sprom->gpio2, 0xff, fallback);

include/linux/ssb/ssb.h +1 -0

index 07ef9b8..4568a5c 100644
@@ -33,6 +33,7 @@ struct ssb_sprom {
 	u8 et1phyaddr;		/* MII address for enet1 */
 	u8 et0mdcport;		/* MDIO for enet0 */
 	u8 et1mdcport;		/* MDIO for enet1 */
+	u16 dev_id;		/* Device ID overriding e.g. PCI ID */
 	u16 board_rev;		/* Board revision number from SPROM. */
 	u16 board_num;		/* Board number from SPROM. */
 	u16 board_type;		/* Board type from SPROM. */

There is also a vendid var which should be used. See this code from brcmsmac:
http://lxr.free-electrons.com/source/drivers/staging/brcm80211/brcmsmac/wlc_bmac.c?v=3.0#L660