Messages in this thread | | | Date | Tue, 3 Apr 2012 09:53:20 -0700 | From | Chris Wright <> | Subject | Re: [PATCH-v3] Support M95040 SPI EEPROM |
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* Ivo Sieben (meltedpianoman@gmail.com) wrote: > + instr = AT25_READ; > + if (at25->chip.flags & EE_INSTR_BIT3_IS_ADDR) > + if (offset >= (1U << (at25->addrlen * 8))) > + instr |= AT25_INSTR_BIT3; > + *cp++ = instr; <snip> > + /* > + * Certain EEPROMS have a size that is larger than the number of address > + * bytes would allow (e.g. like M95040 from ST that has 512 Byte size > + * but uses only one address byte (A0 to A7) for addressing.) For > + * the extra address bit (A8, A16 or A24) bit 3 of the instruction byte > + * is used. This instruction bit is normally defined as don't care for > + * other AT25 like chips. > + */ > +#define EE_INSTR_BIT3_IS_ADDR 0x0010
Is there some guarantee that this chip flag will always have this meaning?
thanks, -chris
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