diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/linux/eeprom.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/linux/eeprom.h')
-rw-r--r-- | include/linux/eeprom.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/include/linux/eeprom.h b/include/linux/eeprom.h new file mode 100644 index 00000000000..38afd9da1df --- /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) +{ +} |