[PATCH] mfd: si476x: Modernize GPIO handling

Linus Walleij
2026-03-27T08:37:29Z

The SI476X driver depends on the legacy GPIO API. As it only
really use a single GPIO for reset, and this can be easily converted
to use a GPIO descriptor, modernize the driver.

The "reset" GPIO is obtained from a device property, such as a
device tree ("reset-gpios", which is standard, but this hardware has
no DT bindings as of now) or a software node for static platforms.

Out-of-tree users can easily adopt to providing a GPIO descriptor
this way.

Signed-off-by: Linus Walleij <linusw@kernel.org>
---
drivers/mfd/Kconfig | 1 -
drivers/mfd/si476x-cmd.c | 1 -
drivers/mfd/si476x-i2c.c | 46 +++++++++++++------------------------
include/linux/mfd/si476x-core.h | 5 ++--
include/linux/mfd/si476x-platform.h | 2 --
5 files changed, 19 insertions(+), 36 deletions(-)

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 7192c9d1d268..a5fd07366d8c 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1468,7 +1468,6 @@ config MFD_SEC_I2C
config MFD_SI476X_CORE
tristate "Silicon Laboratories 4761/64/68 AM/FM radio."
depends on I2C
- depends on GPIOLIB_LEGACY
select MFD_CORE
select REGMAP_I2C
help
diff --git a/drivers/mfd/si476x-cmd.c b/drivers/mfd/si476x-cmd.c
index 3bb2decfebd3..58e9bea7e90a 100644
--- a/drivers/mfd/si476x-cmd.c
+++ b/drivers/mfd/si476x-cmd.c
@@ -15,7 +15,6 @@
#include <linux/atomic.h>
#include <linux/i2c.h>
#include <linux/device.h>
-#include <linux/gpio.h>
#include <linux/videodev2.h>

#include <linux/mfd/si476x-core.h>
diff --git a/drivers/mfd/si476x-i2c.c b/drivers/mfd/si476x-i2c.c
index 899c0b5ea3aa..d9ef1776a703 100644
--- a/drivers/mfd/si476x-i2c.c
+++ b/drivers/mfd/si476x-i2c.c
@@ -13,7 +13,7 @@
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/i2c.h>
#include <linux/err.h>
@@ -130,8 +130,8 @@ int si476x_core_start(struct si476x_core *core, bool soft)
int err;

if (!soft) {
- if (gpio_is_valid(core->gpio_reset))
- gpio_set_value_cansleep(core->gpio_reset, 1);
+ if (core->reset)
+ gpiod_set_value_cansleep(core->reset, 0);

if (client->irq)
enable_irq(client->irq);
@@ -197,8 +197,8 @@ int si476x_core_start(struct si476x_core *core, bool soft)
else
cancel_delayed_work_sync(&core->status_monitor);

- if (gpio_is_valid(core->gpio_reset))
- gpio_set_value_cansleep(core->gpio_reset, 0);
+ if (core->reset)
+ gpiod_set_value_cansleep(core->reset, 1);

return err;
}
@@ -243,8 +243,8 @@ int si476x_core_stop(struct si476x_core *core, bool soft)
cancel_delayed_work_sync(&core->status_monitor);

if (!soft) {
- if (gpio_is_valid(core->gpio_reset))
- gpio_set_value_cansleep(core->gpio_reset, 0);
+ if (core->reset)
+ gpiod_set_value_cansleep(core->reset, 1);
}
return err;
}
@@ -712,24 +712,18 @@ static int si476x_core_probe(struct i2c_client *client)
atomic_set(&core->is_alive, 0);
core->power_state = SI476X_POWER_DOWN;

+ core->reset = devm_gpiod_get_optional(&client->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(core->reset))
+ return dev_err_probe(&client->dev, PTR_ERR(core->reset),
+ "error getting reset GPIO\n");
+ gpiod_set_consumer_name(core->reset, "si476x reset");
+
pdata = dev_get_platdata(&client->dev);
if (pdata) {
memcpy(&core->power_up_parameters,
&pdata->power_up_parameters,
sizeof(core->power_up_parameters));
-
- core->gpio_reset = -1;
- if (gpio_is_valid(pdata->gpio_reset)) {
- rval = gpio_request(pdata->gpio_reset, "si476x reset");
- if (rval) {
- dev_err(&client->dev,
- "Failed to request gpio: %d\n", rval);
- return rval;
- }
- core->gpio_reset = pdata->gpio_reset;
- gpio_direction_output(core->gpio_reset, 0);
- }
-
core->diversity_mode = pdata->diversity_mode;
memcpy(&core->pinmux, &pdata->pinmux,
sizeof(struct si476x_pinmux));
@@ -748,7 +742,7 @@ static int si476x_core_probe(struct i2c_client *client)
core->supplies);
if (rval) {
dev_err(&client->dev, "Failed to get all of the regulators\n");
- goto free_gpio;
+ return rval;
}

mutex_init(&core->cmd_lock);
@@ -761,7 +755,7 @@ static int si476x_core_probe(struct i2c_client *client)
GFP_KERNEL);
if (rval) {
dev_err(&client->dev, "Could not allocate the FIFO\n");
- goto free_gpio;
+ return rval;
}
mutex_init(&core->rds_drainer_status_lock);
init_waitqueue_head(&core->rds_read_queue);
@@ -827,11 +821,6 @@ static int si476x_core_probe(struct i2c_client *client)

free_kfifo:
kfifo_free(&core->rds_fifo);
-
-free_gpio:
- if (gpio_is_valid(core->gpio_reset))
- gpio_free(core->gpio_reset);
-
return rval;
}

@@ -848,9 +837,6 @@ static void si476x_core_remove(struct i2c_client *client)
cancel_delayed_work_sync(&core->status_monitor);

kfifo_free(&core->rds_fifo);
-
- if (gpio_is_valid(core->gpio_reset))
- gpio_free(core->gpio_reset);
}

diff --git a/include/linux/mfd/si476x-core.h b/include/linux/mfd/si476x-core.h
index dd95c37ca134..e31c4433670a 100644
--- a/include/linux/mfd/si476x-core.h
+++ b/include/linux/mfd/si476x-core.h
@@ -14,6 +14,7 @@

#include <linux/kfifo.h>
#include <linux/atomic.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/mutex.h>
@@ -103,7 +104,7 @@ enum si476x_power_state {
* @state: Current power state of the device.
* @supplues: Structure containing handles to all power supplies used
* by the device (NULL ones are ignored).
- * @gpio_reset: GPIO pin connectet to the RSTB pin of the chip.
+ * @reset: GPIO connected to the RSTB pin of the chip.
* @pinmux: Chip's configurable pins configuration.
* @diversity_mode: Chips role when functioning in diversity mode.
* @status_monitor: Polling worker used in polling use case scenarion
@@ -139,7 +140,7 @@ struct si476x_core {

struct regulator_bulk_data supplies[4];

- int gpio_reset;
+ struct gpio_desc *reset;

struct si476x_pinmux pinmux;
enum si476x_phase_diversity_mode diversity_mode;
diff --git a/include/linux/mfd/si476x-platform.h b/include/linux/mfd/si476x-platform.h
index cb99e16ca947..f9e1f6b27277 100644
--- a/include/linux/mfd/si476x-platform.h
+++ b/include/linux/mfd/si476x-platform.h
@@ -246,8 +246,6 @@ enum si476x_phase_diversity_mode {
* Platform dependent definition
*/
struct si476x_platform_data {
- int gpio_reset; /* < 0 if not used */
-
struct si476x_power_up_args power_up_parameters;
enum si476x_phase_diversity_mode diversity_mode;

---
base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
change-id: 20260327-mfd-si476x-df4906f97129

Best regards,
--
Linus Walleij <linusw@kernel.org>