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-rw-r--r--include/linux/eeprom.h136
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)
+{
+}