[PATCH 2/3] iio: adc: ltc2497: add support for LTC2495

Yusuf Alper Bilgin posted 3 patches 1 month, 3 weeks ago
There is a newer version of this series
[PATCH 2/3] iio: adc: ltc2497: add support for LTC2495
Posted by Yusuf Alper Bilgin 1 month, 3 weeks ago
This updates the LTC2497 driver to also support the LTC2495.

Signed-off-by: Yusuf Alper Bilgin <y.alperbilgin@gmail.com>
---
 drivers/iio/adc/ltc2497-core.c | 20 +++++++++-----------
 drivers/iio/adc/ltc2497.c      |  7 +++++++
 drivers/iio/adc/ltc2497.h      |  4 +---
 3 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/drivers/iio/adc/ltc2497-core.c b/drivers/iio/adc/ltc2497-core.c
index 2dc5c704426949a4ec62c42591d6c2c40ffb79cc..400f4fe5af30e8e16b75506726235f10f2a4237f 100644
--- a/drivers/iio/adc/ltc2497-core.c
+++ b/drivers/iio/adc/ltc2497-core.c
@@ -15,9 +15,12 @@
 
 #include "ltc2497.h"
 
-#define LTC2497_SGL			BIT(4)
-#define LTC2497_DIFF			0
-#define LTC2497_SIGN			BIT(3)
+#define LTC2497_CONFIG_DEFAULT		LTC2497_ENABLE
+#define LTC2497_CONVERSION_TIME_MS	150ULL
+
+#define LTC2497_SGL	BIT(4)
+#define LTC2497_DIFF	0
+#define LTC2497_SIGN	BIT(3)
 
 static int ltc2497core_wait_conv(struct ltc2497core_driverdata *ddata)
 {
@@ -26,20 +29,15 @@ static int ltc2497core_wait_conv(struct ltc2497core_driverdata *ddata)
 	time_elapsed = ktime_ms_delta(ktime_get(), ddata->time_prev);
 
 	if (time_elapsed < LTC2497_CONVERSION_TIME_MS) {
-		/* delay if conversion time not passed
-		 * since last read or write
-		 */
-		if (msleep_interruptible(
-		    LTC2497_CONVERSION_TIME_MS - time_elapsed))
+		/* delay if conversion time not passed since last read or write */
+		if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS - time_elapsed))
 			return -ERESTARTSYS;
 
 		return 0;
 	}
 
 	if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) {
-		/* We're in automatic mode -
-		 * so the last reading is still not outdated
-		 */
+		/* We're in automatic mode - so the last reading is still not outdated */
 		return 0;
 	}
 
diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c
index eb9d521e86e54def0493ea0e81f63b37900c56a5..8f4665547b5b0d32084599f8557c40102c37a4ce 100644
--- a/drivers/iio/adc/ltc2497.c
+++ b/drivers/iio/adc/ltc2497.c
@@ -19,6 +19,7 @@
 #include "ltc2497.h"
 
 enum ltc2497_chip_type {
+	TYPE_LTC2495,
 	TYPE_LTC2497,
 	TYPE_LTC2499,
 };
@@ -131,6 +132,10 @@ static void ltc2497_remove(struct i2c_client *client)
 }
 
 static const struct ltc2497_chip_info ltc2497_info[] = {
+	[TYPE_LTC2495] = {
+		.resolution = 16,
+		.name = "ltc2495",
+	},
 	[TYPE_LTC2497] = {
 		.resolution = 16,
 		.name = NULL,
@@ -142,6 +147,7 @@ static const struct ltc2497_chip_info ltc2497_info[] = {
 };
 
 static const struct i2c_device_id ltc2497_id[] = {
+	{ "ltc2495", (kernel_ulong_t)&ltc2497_info[TYPE_LTC2495] },
 	{ "ltc2497", (kernel_ulong_t)&ltc2497_info[TYPE_LTC2497] },
 	{ "ltc2499", (kernel_ulong_t)&ltc2497_info[TYPE_LTC2499] },
 	{ }
@@ -149,6 +155,7 @@ static const struct i2c_device_id ltc2497_id[] = {
 MODULE_DEVICE_TABLE(i2c, ltc2497_id);
 
 static const struct of_device_id ltc2497_of_match[] = {
+	{ .compatible = "lltc,ltc2495", .data = &ltc2497_info[TYPE_LTC2495] },
 	{ .compatible = "lltc,ltc2497", .data = &ltc2497_info[TYPE_LTC2497] },
 	{ .compatible = "lltc,ltc2499", .data = &ltc2497_info[TYPE_LTC2499] },
 	{ }
diff --git a/drivers/iio/adc/ltc2497.h b/drivers/iio/adc/ltc2497.h
index 64e81c95a3dd05911b6717c09ac0560c9f47f304..f2139f260c3fe4e8772c6db9c46331de775dcd5c 100644
--- a/drivers/iio/adc/ltc2497.h
+++ b/drivers/iio/adc/ltc2497.h
@@ -1,8 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
-#define LTC2497_ENABLE			0xA0
-#define LTC2497_CONFIG_DEFAULT		LTC2497_ENABLE
-#define LTC2497_CONVERSION_TIME_MS	150ULL
+#define LTC2497_ENABLE	0xA0
 
 struct ltc2497_chip_info {
 	u32 resolution;

-- 
2.43.0
Re: [PATCH 2/3] iio: adc: ltc2497: add support for LTC2495
Posted by Andy Shevchenko 1 month, 3 weeks ago
On Tue, Aug 12, 2025 at 7:09 PM Yusuf Alper Bilgin
<y.alperbilgin@gmail.com> wrote:
>
> This updates the LTC2497 driver to also support the LTC2495.

...

> +#define LTC2497_CONVERSION_TIME_MS     150ULL

Why ULL? (Mainly why the 'L'/'LL'?)

...

>         if (time_elapsed < LTC2497_CONVERSION_TIME_MS) {
> -               /* delay if conversion time not passed
> -                * since last read or write
> -                */
> -               if (msleep_interruptible(
> -                   LTC2497_CONVERSION_TIME_MS - time_elapsed))
> +               /* delay if conversion time not passed since last read or write */
> +               if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS - time_elapsed))
>                         return -ERESTARTSYS;
>
>                 return 0;
>         }
>
>         if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) {
> -               /* We're in automatic mode -
> -                * so the last reading is still not outdated
> -                */
> +               /* We're in automatic mode - so the last reading is still not outdated */
>                 return 0;
>         }

AFAICS these are unrelated changes. Please, strip them and if you
wish, create a new patch.

...

> -#define LTC2497_ENABLE                 0xA0

> +#define LTC2497_ENABLE 0xA0

Why?!

> -#define LTC2497_CONFIG_DEFAULT         LTC2497_ENABLE
> -#define LTC2497_CONVERSION_TIME_MS     150ULL

Unrelated.

-- 
With Best Regards,
Andy Shevchenko