lkml.org 
[lkml]   [2020]   [Feb]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 7/9] iio: imu: adis: add support product ID check in adis_initial_startup
Date
Each driver/chip that wants to validate it's product id, can now
specify a 'prod_id_reg' and an expected 'prod_id' value.
The 'prod_id' value is intentionally left 0 (uninitialized). There aren't
(yet) any product IDs with value 0; this enforces that both 'prod_id_reg'
and 'prod_id' are specified.

At the very least, this routine validates that the SPI connection to the
ADIS chip[s] works well.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
---
drivers/iio/imu/adis.c | 23 ++++++++++++++++++++++-
include/linux/iio/imu/adis.h | 5 +++++
2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/imu/adis.c b/drivers/iio/imu/adis.c
index 0bd6e32cf577..a8afd01de4f3 100644
--- a/drivers/iio/imu/adis.c
+++ b/drivers/iio/imu/adis.c
@@ -373,6 +373,10 @@ static int adis_self_test(struct adis *adis)
* via GPIOLIB. If no pin is configured a SW reset will be performed.
* The RST pin for the ADIS devices should be configured as ACTIVE_LOW.
*
+ * After the self-test operation is performed, the function will also check
+ * that the product ID is as expected. This assumes that drivers providing
+ * 'prod_id_reg' will also provide the 'prod_id'.
+ *
* Returns 0 if the device is operational, a negative error code otherwise.
*
* This function should be called early on in the device initialization sequence
@@ -382,6 +386,7 @@ int __adis_initial_startup(struct adis *adis)
{
const struct adis_timeout *timeouts = adis->data->timeouts;
struct gpio_desc *gpio;
+ uint16_t prod_id;
int ret;

/* check if the device has rst pin low */
@@ -401,7 +406,23 @@ int __adis_initial_startup(struct adis *adis)
return ret;
}

- return adis_self_test(adis);
+ ret = adis_self_test(adis);
+ if (ret)
+ return ret;
+
+ if (!adis->data->prod_id_reg)
+ return 0;
+
+ ret = adis_read_reg_16(adis, adis->data->prod_id_reg, &prod_id);
+ if (ret)
+ return ret;
+
+ if (prod_id != adis->data->prod_id)
+ dev_warn(&adis->spi->dev,
+ "Device ID(%u) and product ID(%u) do not match.",
+ adis->data->prod_id, prod_id);
+
+ return 0;
}
EXPORT_SYMBOL_GPL(__adis_initial_startup);

diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h
index b7feca4e5f26..ac7cfd073804 100644
--- a/include/linux/iio/imu/adis.h
+++ b/include/linux/iio/imu/adis.h
@@ -41,6 +41,8 @@ struct adis_timeout {
* @glob_cmd_reg: Register address of the GLOB_CMD register
* @msc_ctrl_reg: Register address of the MSC_CTRL register
* @diag_stat_reg: Register address of the DIAG_STAT register
+ * @prod_id_reg: Register address of the PROD_ID register
+ * @prod_id: Product ID code that should be expected when reading @prod_id_reg
* @self_test_reg: Register address to request self test command
* @status_error_msgs: Array of error messgaes
* @status_error_mask:
@@ -54,6 +56,9 @@ struct adis_data {
unsigned int glob_cmd_reg;
unsigned int msc_ctrl_reg;
unsigned int diag_stat_reg;
+ unsigned int prod_id_reg;
+
+ unsigned int prod_id;

unsigned int self_test_mask;
unsigned int self_test_reg;
--
2.20.1
\
 
 \ /
  Last update: 2020-02-10 14:29    [W:0.129 / U:9.388 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site