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path: root/drivers/misc/eeprom/at25.c
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Diffstat (limited to 'drivers/misc/eeprom/at25.c')
-rw-r--r--drivers/misc/eeprom/at25.c19
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c
index 01ab3c9b4cf7..0842c2994ee2 100644
--- a/drivers/misc/eeprom/at25.c
+++ b/drivers/misc/eeprom/at25.c
@@ -50,6 +50,7 @@ struct at25_data {
#define AT25_SR_BP1 0x08
#define AT25_SR_WPEN 0x80 /* writeprotect enable */
+#define AT25_INSTR_BIT3 0x08 /* Additional address bit in instr */
#define EE_MAXADDRLEN 3 /* 24 bit addresses, up to 2 MBytes */
@@ -75,6 +76,7 @@ at25_ee_read(
ssize_t status;
struct spi_transfer t[2];
struct spi_message m;
+ u8 instr;
if (unlikely(offset >= at25->bin.size))
return 0;
@@ -84,7 +86,12 @@ at25_ee_read(
return count;
cp = command;
- *cp++ = AT25_READ;
+
+ instr = AT25_READ;
+ if (at25->chip.flags & EE_INSTR_BIT3_IS_ADDR)
+ if (offset >= (1U << (at25->addrlen * 8)))
+ instr |= AT25_INSTR_BIT3;
+ *cp++ = instr;
/* 8/16/24-bit address is written MSB first */
switch (at25->addrlen) {
@@ -167,14 +174,14 @@ at25_ee_write(struct at25_data *at25, const char *buf, loff_t off,
/* For write, rollover is within the page ... so we write at
* most one page, then manually roll over to the next page.
*/
- bounce[0] = AT25_WRITE;
mutex_lock(&at25->lock);
do {
unsigned long timeout, retries;
unsigned segment;
unsigned offset = (unsigned) off;
- u8 *cp = bounce + 1;
+ u8 *cp = bounce;
int sr;
+ u8 instr;
*cp = AT25_WREN;
status = spi_write(at25->spi, cp, 1);
@@ -184,6 +191,12 @@ at25_ee_write(struct at25_data *at25, const char *buf, loff_t off,
break;
}
+ instr = AT25_WRITE;
+ if (at25->chip.flags & EE_INSTR_BIT3_IS_ADDR)
+ if (offset >= (1U << (at25->addrlen * 8)))
+ instr |= AT25_INSTR_BIT3;
+ *cp++ = instr;
+
/* 8/16/24-bit address is written MSB first */
switch (at25->addrlen) {
default: /* case 3 */