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-rw-r--r--include/linux/spi/eeprom.h37
1 files changed, 37 insertions, 0 deletions
diff --git a/include/linux/spi/eeprom.h b/include/linux/spi/eeprom.h
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+++ b/include/linux/spi/eeprom.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_SPI_EEPROM_H
+#define __LINUX_SPI_EEPROM_H
+
+#include <linux/memory.h>
+
+/*
+ * Put one of these structures in platform_data for SPI EEPROMS handled
+ * by the "at25" driver. On SPI, most EEPROMS understand the same core
+ * command set. If you need to support EEPROMs that don't yet fit, add
+ * flags to support those protocol options. These values all come from
+ * the chip datasheets.
+ */
+struct spi_eeprom {
+ u32 byte_len;
+ char name[10];
+ u32 page_size; /* for writes */
+ u16 flags;
+#define EE_ADDR1 0x0001 /* 8 bit addrs */
+#define EE_ADDR2 0x0002 /* 16 bit addrs */
+#define EE_ADDR3 0x0004 /* 24 bit addrs */
+#define EE_READONLY 0x0008 /* disallow writes */
+
+ /*
+ * 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
+
+ void *context;
+};
+
+#endif /* __LINUX_SPI_EEPROM_H */