From: Christian Eggers > Sent: 28 July 2020 10:30 > > SPI eeproms are addressed by byte. They also support multi-byte writes - possibly with alignment restrictions. So forcing 4-byte writes (at aligned addresses) would typically speed up writes by a factor of 4 over byte writes. So does this fix a problem? If so what. So setting the 'stride' to 4 may be a compromise. Looking at some code that writes the EPCQ for Altera FPGA (which I think is just SPI) it does aligned 256 byte writes. The long writes (and the 4-bit physical interface) are needed to get the write times down to a sensible value. David > > Signed-off-by: Christian Eggers <ceggers@xxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > --- > drivers/misc/eeprom/at25.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c > index 0e7c8dc01195..4e57eb145fcc 100644 > --- a/drivers/misc/eeprom/at25.c > +++ b/drivers/misc/eeprom/at25.c > @@ -358,7 +358,7 @@ static int at25_probe(struct spi_device *spi) > at25->nvmem_config.reg_read = at25_ee_read; > at25->nvmem_config.reg_write = at25_ee_write; > at25->nvmem_config.priv = at25; > - at25->nvmem_config.stride = 4; > + at25->nvmem_config.stride = 1; > at25->nvmem_config.word_size = 1; > at25->nvmem_config.size = chip.byte_len; > > -- > Christian Eggers > Embedded software developer > > Arnold & Richter Cine Technik GmbH & Co. Betriebs KG > Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRA 57918 > Persoenlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH > Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRB 54477 > Geschaeftsfuehrer: Dr. Michael Neuhaeuser; Stephan Schenk; Walter Trauninger; Markus Zeiler - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
