[PATCH v8 4/5] nvmem: eeprom: at25: export FRAM serial num
From: Jiri Prchal <hidden>
Date: 2021-06-07 16:12:15
Also in:
lkml
Subsystem:
char and misc drivers, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds
This exports serial number of FRAM in sysfs file named "sernum". Formatted in hex, each byte separated by space. Example: $ cat /sys/class/spi_master/spi0/spi0.0/sernum 0000a43644f2ae6c Signed-off-by: Jiri Prchal <redacted> --- v2: no change here v3: resend and added more recipients v4: resend v5: reworked up on Greg comments: no spaces in string, sysfs done correctly v6: no change here v7: moved FM25_SN_LEN, static array, used sysfs_emit, DEVICE_ATTR_RO v8: clarify sysfs_emit format --- drivers/misc/eeprom/at25.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c
index e25cec7c474b..4a47a7e2d90d 100644
--- a/drivers/misc/eeprom/at25.c
+++ b/drivers/misc/eeprom/at25.c@@ -31,6 +31,7 @@ * AT25M02, AT25128B */ +#define FM25_SN_LEN 8 /* serial number length */ struct at25_data { struct spi_device *spi; struct mutex lock;
@@ -39,6 +40,7 @@ struct at25_data { struct nvmem_config nvmem_config; struct nvmem_device *nvmem; int has_sernum; + u8 sernum[FM25_SN_LEN]; }; #define AT25_WREN 0x06 /* latch the write enable */
@@ -172,6 +174,21 @@ static int fm25_aux_read(struct at25_data *at25, u8 *buf, uint8_t command, return status; } +static ssize_t sernum_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct at25_data *at25; + + at25 = dev_get_drvdata(dev); + return sysfs_emit(buf, "%*phN\n", sizeof at25->sernum, at25->sernum); +} +static DEVICE_ATTR_RO(sernum); + +static struct attribute *sernum_attrs[] = { + &dev_attr_sernum.attr, + NULL, +}; +ATTRIBUTE_GROUPS(sernum); + static int at25_ee_write(void *priv, unsigned int off, void *val, size_t count) { struct at25_data *at25 = priv;
@@ -416,8 +433,10 @@ static int at25_probe(struct spi_device *spi) else at25->chip.flags |= EE_ADDR2; - if (id[8]) + if (id[8]) { at25->has_sernum = 1; + fm25_aux_read(at25, at25->sernum, FM25_RDSN, FM25_SN_LEN); + } else at25->has_sernum = 0;
@@ -471,6 +490,7 @@ static struct spi_driver at25_driver = { .driver = { .name = "at25", .of_match_table = at25_of_match, + .dev_groups = sernum_groups, }, .probe = at25_probe, };
--
2.25.1