Adds sopport for Cypress FRAMs.
Jiri Prchal (3):
nvmem: eeprom: at25: add support for FRAM
nvmem: eeprom: at25: add support for FRAM
nvmem: eeprom: add documentation for FRAM
.../devicetree/bindings/eeprom/at25.yaml | 12 +-
drivers/misc/eeprom/Kconfig | 5 +-
drivers/misc/eeprom/at25.c | 151 ++++++++++++++----
drivers/nvmem/core.c | 4 +
include/linux/nvmem-provider.h | 1 +
5 files changed, 139 insertions(+), 34 deletions(-)
--
2.25.1
Added enum and string for FRAM to expose it as "fram".
Signed-off-by: Jiri Prchal <[email protected]>
---
drivers/nvmem/core.c | 4 ++++
include/linux/nvmem-provider.h | 1 +
2 files changed, 5 insertions(+)
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 177f5bf27c6d..01ef9a934b0a 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -180,6 +180,7 @@ static const char * const nvmem_type_str[] = {
[NVMEM_TYPE_EEPROM] = "EEPROM",
[NVMEM_TYPE_OTP] = "OTP",
[NVMEM_TYPE_BATTERY_BACKED] = "Battery backed",
+ [NVMEM_TYPE_FRAM] = "FRAM",
};
#ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -359,6 +360,9 @@ static int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem,
if (!config->base_dev)
return -EINVAL;
+ if (config->type == NVMEM_TYPE_FRAM)
+ bin_attr_nvmem_eeprom_compat.attr.name = "fram";
+
nvmem->eeprom = bin_attr_nvmem_eeprom_compat;
nvmem->eeprom.attr.mode = nvmem_bin_attr_get_umode(nvmem);
nvmem->eeprom.size = nvmem->size;
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index e162b757b6d5..890003565761 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -25,6 +25,7 @@ enum nvmem_type {
NVMEM_TYPE_EEPROM,
NVMEM_TYPE_OTP,
NVMEM_TYPE_BATTERY_BACKED,
+ NVMEM_TYPE_FRAM,
};
#define NVMEM_DEVID_NONE (-1)
--
2.25.1
Added dt binding documentation.
Signed-off-by: Jiri Prchal <[email protected]>
---
Documentation/devicetree/bindings/eeprom/at25.yaml | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/eeprom/at25.yaml b/Documentation/devicetree/bindings/eeprom/at25.yaml
index 121a601db22e..f9191b67080d 100644
--- a/Documentation/devicetree/bindings/eeprom/at25.yaml
+++ b/Documentation/devicetree/bindings/eeprom/at25.yaml
@@ -4,7 +4,7 @@
$id: "http://devicetree.org/schemas/eeprom/at25.yaml#"
$schema: "http://devicetree.org/meta-schemas/core.yaml#"
-title: SPI EEPROMs compatible with Atmel's AT25
+title: SPI EEPROMs or FRAMs compatible with Atmel's AT25
maintainers:
- Christian Eggers <[email protected]>
@@ -31,6 +31,7 @@ properties:
- microchip,25lc040
- st,m95m02
- st,m95256
+ - cypress,fm25
- const: atmel,at25
@@ -48,7 +49,7 @@ properties:
$ref: /schemas/types.yaml#/definitions/uint32
enum: [1, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072]
description:
- Size of the eeprom page.
+ Size of the eeprom page. FRAMs don't have pages.
size:
$ref: /schemas/types.yaml#/definitions/uint32
@@ -101,6 +102,7 @@ required:
- compatible
- reg
- spi-max-frequency
+ # these are for eeproms only
- pagesize
- size
- address-width
@@ -127,3 +129,9 @@ examples:
address-width = <16>;
};
};
+
+ fram@1 {
+ compatible = "cypress,fm25";
+ reg = <1>;
+ spi-max-frequency = <40000000>;
+ };
--
2.25.1
Added support for Cypress FRAMs.
These frams have ID and some of them have serial number too.
Size of them is recognized by ID. They don't have pages, it could
be read or written at once, but it's limited in this driver to
io limit 4096.
Signed-off-by: Jiri Prchal <[email protected]>
---
drivers/misc/eeprom/Kconfig | 5 +-
drivers/misc/eeprom/at25.c | 151 +++++++++++++++++++++++++++++-------
2 files changed, 124 insertions(+), 32 deletions(-)
diff --git a/drivers/misc/eeprom/Kconfig b/drivers/misc/eeprom/Kconfig
index 0f791bfdc1f5..f0a7531f354c 100644
--- a/drivers/misc/eeprom/Kconfig
+++ b/drivers/misc/eeprom/Kconfig
@@ -32,12 +32,13 @@ config EEPROM_AT24
will be called at24.
config EEPROM_AT25
- tristate "SPI EEPROMs from most vendors"
+ tristate "SPI EEPROMs (FRAMs) from most vendors"
depends on SPI && SYSFS
select NVMEM
select NVMEM_SYSFS
help
- Enable this driver to get read/write support to most SPI EEPROMs,
+ Enable this driver to get read/write support to most SPI EEPROMs
+ and Cypress FRAMs,
after you configure the board init code to know about each eeprom
on your target board.
diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c
index b76e4901b4a4..0d0a00a0f7e7 100644
--- a/drivers/misc/eeprom/at25.c
+++ b/drivers/misc/eeprom/at25.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* at25.c -- support most SPI EEPROMs, such as Atmel AT25 models
+ * and Cypress FRAMs FM25 models
*
* Copyright (C) 2006 David Brownell
*/
@@ -16,6 +17,8 @@
#include <linux/spi/spi.h>
#include <linux/spi/eeprom.h>
#include <linux/property.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
/*
* NOTE: this is an *EEPROM* driver. The vagaries of product naming
@@ -34,6 +37,7 @@ struct at25_data {
unsigned addrlen;
struct nvmem_config nvmem_config;
struct nvmem_device *nvmem;
+ int has_sernum;
};
#define AT25_WREN 0x06 /* latch the write enable */
@@ -42,6 +46,9 @@ struct at25_data {
#define AT25_WRSR 0x01 /* write status register */
#define AT25_READ 0x03 /* read byte(s) */
#define AT25_WRITE 0x02 /* write byte(s)/sector */
+#define FM25_SLEEP 0xb9 /* enter sleep mode */
+#define FM25_RDID 0x9f /* read device ID */
+#define FM25_RDSN 0xc3 /* read S/N */
#define AT25_SR_nRDY 0x01 /* nRDY = write-in-progress */
#define AT25_SR_WEN 0x02 /* write enable (latched) */
@@ -51,6 +58,9 @@ struct at25_data {
#define AT25_INSTR_BIT3 0x08 /* Additional address bit in instr */
+#define FM25_ID_LEN 9 /* ID length */
+#define FM25_SN_LEN 8 /* serial number length */
+
#define EE_MAXADDRLEN 3 /* 24 bit addresses, up to 2 MBytes */
/* Specs often allow 5 msec for a page write, sometimes 20 msec;
@@ -58,6 +68,9 @@ struct at25_data {
*/
#define EE_TIMEOUT 25
+#define IS_EEPROM 0
+#define IS_FRAM 1
+
/*-------------------------------------------------------------------------*/
#define io_limit PAGE_SIZE /* bytes */
@@ -129,6 +142,36 @@ static int at25_ee_read(void *priv, unsigned int offset,
return status;
}
+/*
+ * read extra registers as ID or serial number
+ */
+static int fm25_aux_read(struct at25_data *at25, char *buf, uint8_t command,
+ int len)
+{
+ int status;
+ struct spi_transfer t[2];
+ struct spi_message m;
+
+ spi_message_init(&m);
+ memset(t, 0, sizeof(t));
+
+ t[0].tx_buf = &command;
+ t[0].len = 1;
+ spi_message_add_tail(&t[0], &m);
+
+ t[1].rx_buf = buf;
+ t[1].len = len;
+ spi_message_add_tail(&t[1], &m);
+
+ mutex_lock(&at25->lock);
+
+ status = spi_sync(at25->spi, &m);
+ dev_dbg(&at25->spi->dev, "read %zu aux bytes --> %zd\n", len, status);
+
+ mutex_unlock(&at25->lock);
+ return status;
+}
+
static int at25_ee_write(void *priv, unsigned int off, void *val, size_t count)
{
struct at25_data *at25 = priv;
@@ -303,34 +346,48 @@ static int at25_fw_to_chip(struct device *dev, struct spi_eeprom *chip)
return 0;
}
+static const struct of_device_id at25_of_match[] = {
+ { .compatible = "atmel,at25", .data = (const void *)IS_EEPROM },
+ { .compatible = "cypress,fm25", .data = (const void *)IS_FRAM },
+ { }
+};
+MODULE_DEVICE_TABLE(of, at25_of_match);
+
+static int mypow(int x, int n)
+{
+ int i;
+ int res = 1;
+
+ for (i = 0; i < n; ++i)
+ res *= x;
+
+ return res;
+}
+
static int at25_probe(struct spi_device *spi)
{
struct at25_data *at25 = NULL;
struct spi_eeprom chip;
int err;
int sr;
- int addrlen;
+ char id[FM25_ID_LEN];
+ const struct of_device_id *match;
+ int is_fram = 0;
+
+ match = of_match_device(of_match_ptr(at25_of_match), &spi->dev);
+ if (match)
+ is_fram = (int)(uintptr_t)match->data;
/* Chip description */
if (!spi->dev.platform_data) {
- err = at25_fw_to_chip(&spi->dev, &chip);
- if (err)
- return err;
+ if (!is_fram) {
+ err = at25_fw_to_chip(&spi->dev, &chip);
+ if (err)
+ return err;
+ }
} else
chip = *(struct spi_eeprom *)spi->dev.platform_data;
- /* For now we only support 8/16/24 bit addressing */
- if (chip.flags & EE_ADDR1)
- addrlen = 1;
- else if (chip.flags & EE_ADDR2)
- addrlen = 2;
- else if (chip.flags & EE_ADDR3)
- addrlen = 3;
- else {
- dev_dbg(&spi->dev, "unsupported address type\n");
- return -EINVAL;
- }
-
/* Ping the chip ... the status register is pretty portable,
* unlike probing manufacturer IDs. We do expect that system
* firmware didn't write it in the past few milliseconds!
@@ -349,9 +406,49 @@ static int at25_probe(struct spi_device *spi)
at25->chip = chip;
at25->spi = spi;
spi_set_drvdata(spi, at25);
- at25->addrlen = addrlen;
- at25->nvmem_config.type = NVMEM_TYPE_EEPROM;
+ if (is_fram) {
+ /* Get ID of chip */
+ fm25_aux_read(at25, id, FM25_RDID, FM25_ID_LEN);
+ if (id[6] != 0xc2) {
+ dev_err(&spi->dev,
+ "Error: no Cypress FRAM (id %02x)\n", id[6]);
+ return -ENODEV;
+ }
+ /* set size found in ID */
+ if (id[7] < 0x21 || id[7] > 0x26) {
+ dev_err(&spi->dev, "Error: unsupported size (id %02x)\n", id[7]);
+ return -ENODEV;
+ }
+ chip.byte_len = mypow(2, id[7] - 0x21 + 4) * 1024;
+
+ if (at25->chip.byte_len > 64 * 1024)
+ at25->chip.flags |= EE_ADDR3;
+ else
+ at25->chip.flags |= EE_ADDR2;
+
+ if (id[8])
+ at25->has_sernum = 1;
+ else
+ at25->has_sernum = 0;
+
+ at25->chip.page_size = PAGE_SIZE;
+ strncpy(at25->chip.name, "fm25", sizeof(at25->chip.name));
+ }
+
+ /* For now we only support 8/16/24 bit addressing */
+ if (at25->chip.flags & EE_ADDR1)
+ at25->addrlen = 1;
+ else if (at25->chip.flags & EE_ADDR2)
+ at25->addrlen = 2;
+ else if (at25->chip.flags & EE_ADDR3)
+ at25->addrlen = 3;
+ else {
+ dev_dbg(&spi->dev, "unsupported address type\n");
+ return -EINVAL;
+ }
+
+ at25->nvmem_config.type = is_fram ? NVMEM_TYPE_FRAM : NVMEM_TYPE_EEPROM;
at25->nvmem_config.name = dev_name(&spi->dev);
at25->nvmem_config.dev = &spi->dev;
at25->nvmem_config.read_only = chip.flags & EE_READONLY;
@@ -370,23 +467,17 @@ static int at25_probe(struct spi_device *spi)
if (IS_ERR(at25->nvmem))
return PTR_ERR(at25->nvmem);
- dev_info(&spi->dev, "%d %s %s eeprom%s, pagesize %u\n",
- (chip.byte_len < 1024) ? chip.byte_len : (chip.byte_len / 1024),
- (chip.byte_len < 1024) ? "Byte" : "KByte",
- at25->chip.name,
- (chip.flags & EE_READONLY) ? " (readonly)" : "",
- at25->chip.page_size);
+ dev_info(&spi->dev, "%d %s %s %s%s, pagesize %u\n",
+ (chip.byte_len < 1024) ? chip.byte_len : (chip.byte_len / 1024),
+ (chip.byte_len < 1024) ? "Byte" : "KByte",
+ at25->chip.name, is_fram ? "fram" : "eeprom",
+ (chip.flags & EE_READONLY) ? " (readonly)" : "",
+ at25->chip.page_size);
return 0;
}
/*-------------------------------------------------------------------------*/
-static const struct of_device_id at25_of_match[] = {
- { .compatible = "atmel,at25", },
- { }
-};
-MODULE_DEVICE_TABLE(of, at25_of_match);
-
static struct spi_driver at25_driver = {
.driver = {
.name = "at25",
--
2.25.1
Hi Jiri,
I have two Fujitsu different FRAMs running with the stock at25 driver. I set
the page size equal to the device size (as FRAMs have no pages).
Are you able to run your FRAM with the unmodified driver?
I assume that getting the device geometry from the chip is vendor specific (in
contrast to flash devices which have standard commands for this). I suppose
that there is no much value getting vendor specific information from a chip. If
the drivers knows the vendor, it should also know the chip (e.g. from the dt).
regards
Christian
On Friday, 9 April 2021, 17:47:17 CEST, Jiri Prchal wrote:
> Adds sopport for Cypress FRAMs.
>
> Jiri Prchal (3):
> nvmem: eeprom: at25: add support for FRAM
> nvmem: eeprom: at25: add support for FRAM
> nvmem: eeprom: add documentation for FRAM
>
> .../devicetree/bindings/eeprom/at25.yaml | 12 +-
> drivers/misc/eeprom/Kconfig | 5 +-
> drivers/misc/eeprom/at25.c | 151 ++++++++++++++----
> drivers/nvmem/core.c | 4 +
> include/linux/nvmem-provider.h | 1 +
> 5 files changed, 139 insertions(+), 34 deletions(-)
>
>
Hi Jiri,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on char-misc/char-misc-testing]
[also build test WARNING on robh/for-next linux/master linus/master v5.12-rc6 next-20210409]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Jiri-Prchal/nvmem-eeprom-add-support-for-FRAM/20210409-235546
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git b195b20b7145bcae22ad261abc52d68336f5e913
config: arm64-randconfig-r033-20210409 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project dd453a1389b6a7e6d9214b449d3c54981b1a89b6)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm64 cross compiling tool for clang build
# apt-get install binutils-aarch64-linux-gnu
# https://github.com/0day-ci/linux/commit/d335df5f35cd09d8f9d7f14e0bfbad45ab2bc33a
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Jiri-Prchal/nvmem-eeprom-add-support-for-FRAM/20210409-235546
git checkout d335df5f35cd09d8f9d7f14e0bfbad45ab2bc33a
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
>> drivers/misc/eeprom/at25.c:169:59: warning: format specifies type 'size_t' (aka 'unsigned long') but the argument has type 'int' [-Wformat]
dev_dbg(&at25->spi->dev, "read %zu aux bytes --> %zd\n", len, status);
~~~ ^~~
%d
include/linux/dev_printk.h:123:39: note: expanded from macro 'dev_dbg'
dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
~~~ ^~~~~~~~~~~
include/linux/dynamic_debug.h:162:19: note: expanded from macro 'dynamic_dev_dbg'
dev, fmt, ##__VA_ARGS__)
~~~ ^~~~~~~~~~~
include/linux/dynamic_debug.h:147:56: note: expanded from macro '_dynamic_func_call'
__dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
^~~~~~~~~~~
include/linux/dynamic_debug.h:129:15: note: expanded from macro '__dynamic_func_call'
func(&id, ##__VA_ARGS__); \
^~~~~~~~~~~
>> drivers/misc/eeprom/at25.c:169:64: warning: format specifies type 'ssize_t' (aka 'long') but the argument has type 'int' [-Wformat]
dev_dbg(&at25->spi->dev, "read %zu aux bytes --> %zd\n", len, status);
~~~ ^~~~~~
%d
include/linux/dev_printk.h:123:39: note: expanded from macro 'dev_dbg'
dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
~~~ ^~~~~~~~~~~
include/linux/dynamic_debug.h:162:19: note: expanded from macro 'dynamic_dev_dbg'
dev, fmt, ##__VA_ARGS__)
~~~ ^~~~~~~~~~~
include/linux/dynamic_debug.h:147:56: note: expanded from macro '_dynamic_func_call'
__dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
^~~~~~~~~~~
include/linux/dynamic_debug.h:129:15: note: expanded from macro '__dynamic_func_call'
func(&id, ##__VA_ARGS__); \
^~~~~~~~~~~
2 warnings generated.
vim +169 drivers/misc/eeprom/at25.c
144
145 /*
146 * read extra registers as ID or serial number
147 */
148 static int fm25_aux_read(struct at25_data *at25, char *buf, uint8_t command,
149 int len)
150 {
151 int status;
152 struct spi_transfer t[2];
153 struct spi_message m;
154
155 spi_message_init(&m);
156 memset(t, 0, sizeof(t));
157
158 t[0].tx_buf = &command;
159 t[0].len = 1;
160 spi_message_add_tail(&t[0], &m);
161
162 t[1].rx_buf = buf;
163 t[1].len = len;
164 spi_message_add_tail(&t[1], &m);
165
166 mutex_lock(&at25->lock);
167
168 status = spi_sync(at25->spi, &m);
> 169 dev_dbg(&at25->spi->dev, "read %zu aux bytes --> %zd\n", len, status);
170
171 mutex_unlock(&at25->lock);
172 return status;
173 }
174
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
On Fri, 09 Apr 2021 17:47:20 +0200, Jiri Prchal wrote:
> Added dt binding documentation.
>
> Signed-off-by: Jiri Prchal <[email protected]>
> ---
> Documentation/devicetree/bindings/eeprom/at25.yaml | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):
yamllint warnings/errors:
dtschema/dtc warnings/errors:
Documentation/devicetree/bindings/eeprom/at25.example.dts:40.17-27: Warning (reg_format): /example-0/fram@1:reg: property has invalid length (4 bytes) (#address-cells == 1, #size-cells == 1)
Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: Warning (pci_device_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: Warning (pci_device_bus_num): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: Warning (simple_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: Warning (i2c_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: Warning (spi_bus_reg): Failed prerequisite 'reg_format'
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: example-0: fram@1:reg:0: [1] is too short
From schema: /usr/local/lib/python3.8/dist-packages/dtschema/schemas/reg.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: fram@1: $nodename:0: 'fram@1' does not match '^eeprom@[0-9a-f]{1,2}$'
From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: fram@1: compatible: 'oneOf' conditional failed, one must be fixed:
['cypress,fm25'] is too short
'atmel,at25' was expected
From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: fram@1: 'pagesize' is a required property
From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: fram@1: 'size' is a required property
From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.example.dt.yaml: fram@1: 'address-width' is a required property
From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/eeprom/at25.yaml
See https://patchwork.ozlabs.org/patch/1464448
This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.
If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:
pip3 install dtschema --upgrade
Please check and re-submit.
On 09. 04. 21 19:21, Christian Eggers wrote:
> Hi Jiri,
>
> I have two Fujitsu different FRAMs running with the stock at25 driver. I set
> the page size equal to the device size (as FRAMs have no pages).
>
> Are you able to run your FRAM with the unmodified driver?
>
> I assume that getting the device geometry from the chip is vendor specific (in
> contrast to flash devices which have standard commands for this). I suppose
> that there is no much value getting vendor specific information from a chip. If
> the drivers knows the vendor, it should also know the chip (e.g. from the dt).
Hi Christian,
main purpose of this patch is to get serial number from this chip. I
don't have it done yet, in older kernels I expose it as separate file in
sysfs, but in this kernel no luck. So a post first things while I'm
working on sernum exposing.
Does your chip has serial number? Can you read it?
Any help welcomed.
Thanks
Jiri
PS: If standard EEPROMs has some commands to get size etc., why it's not
used? I guess that size is increased as time goes while board is still
the same, so isn't it annoying changing dt every new lot with bigger
eeproms.