1 files changed, 136 insertions, 0 deletions

diff --git a/include/linux/eeprom.h b/include/linux/eeprom.h
new file mode 100644
index 000000000000..38afd9da1dfe
--- /dev/null
+++ b/include/linux/eeprom.h
@@ -0,0 +1,136 @@
+/* credit winbond-840.c
+ */
+#include <asm/io.h>
+struct eeprom_ops {
+        void    (*set_cs)(void *ee);
+        void    (*clear_cs)(void *ee);
+};
+
+#define EEPOL_EEDI      0x01
+#define EEPOL_EEDO      0x02
+#define EEPOL_EECLK     0x04
+#define EEPOL_EESEL     0x08
+
+struct eeprom {
+        void *dev;
+        struct eeprom_ops *ops;
+
+        void __iomem *  addr;
+
+        unsigned        ee_addr_bits;
+
+        unsigned        eesel;
+        unsigned        eeclk;
+        unsigned        eedo;
+        unsigned        eedi;
+        unsigned        polarity;
+        unsigned        ee_state;
+
+        spinlock_t      *lock;
+        u32             *cache;
+};
+
+
+u8   eeprom_readb(struct eeprom *ee, unsigned address);
+void eeprom_read(struct eeprom *ee, unsigned address, u8 *bytes,
+                unsigned count);
+void eeprom_writeb(struct eeprom *ee, unsigned address, u8 data);
+void eeprom_write(struct eeprom *ee, unsigned address, u8 *bytes,
+                unsigned count);
+
+/* The EEPROM commands include the alway-set leading bit. */
+enum EEPROM_Cmds {
+        EE_WriteCmd=(5 << 6), EE_ReadCmd=(6 << 6), EE_EraseCmd=(7 << 6),
+};
+
+void setup_ee_mem_bitbanger(struct eeprom *ee, void __iomem *memaddr, int eesel_bit, int eeclk_bit, int eedo_bit, int eedi_bit, unsigned polarity)
+{
+        ee->addr = memaddr;
+        ee->eesel = 1 << eesel_bit;
+        ee->eeclk = 1 << eeclk_bit;
+        ee->eedo = 1 << eedo_bit;
+        ee->eedi = 1 << eedi_bit;
+
+        ee->polarity = polarity;
+
+        *ee->cache = readl(ee->addr);
+}
+
+/* foo. put this in a .c file */
+static inline void eeprom_update(struct eeprom *ee, u32 mask, int pol)
+{
+        unsigned long flags;
+        u32 data;
+
+        spin_lock_irqsave(ee->lock, flags);
+        data = *ee->cache;
+
+        data &= ~mask;
+        if (pol)
+                data |= mask;
+
+        *ee->cache = data;
+//printk("update: %08x\n", data);
+        writel(data, ee->addr);
+        spin_unlock_irqrestore(ee->lock, flags);
+}
+
+void eeprom_clk_lo(struct eeprom *ee)
+{
+        int pol = !!(ee->polarity & EEPOL_EECLK);
+
+        eeprom_update(ee, ee->eeclk, pol);
+        udelay(2);
+}
+
+void eeprom_clk_hi(struct eeprom *ee)
+{
+        int pol = !!(ee->polarity & EEPOL_EECLK);
+
+        eeprom_update(ee, ee->eeclk, !pol);
+        udelay(2);
+}
+
+void eeprom_send_addr(struct eeprom *ee, unsigned address)
+{
+        int pol = !!(ee->polarity & EEPOL_EEDI);
+        unsigned i;
+        address |= 6 << 6;
+
+        /* Shift the read command bits out. */
+        for (i=0; i<11; i++) {
+                eeprom_update(ee, ee->eedi, ((address >> 10) & 1) ^ pol);
+                address <<= 1;
+                eeprom_clk_hi(ee);
+                eeprom_clk_lo(ee);
+        }
+        eeprom_update(ee, ee->eedi, pol);
+}
+
+u16   eeprom_readw(struct eeprom *ee, unsigned address)
+{
+        unsigned i;
+        u16     res = 0;
+
+        eeprom_clk_lo(ee);
+        eeprom_update(ee, ee->eesel, 1 ^ !!(ee->polarity & EEPOL_EESEL));
+        eeprom_send_addr(ee, address);
+
+        for (i=0; i<16; i++) {
+                u32 data;
+                eeprom_clk_hi(ee);
+                res <<= 1;
+                data = readl(ee->addr);
+//printk("eeprom_readw: %08x\n", data);
+                res |= !!(data & ee->eedo) ^ !!(ee->polarity & EEPOL_EEDO);
+                eeprom_clk_lo(ee);
+        }
+        eeprom_update(ee, ee->eesel, 0 ^ !!(ee->polarity & EEPOL_EESEL));
+
+        return res;
+}
+
+
+void eeprom_writeb(struct eeprom *ee, unsigned address, u8 data)
+{
+}