Configuration information is now prioritized from the firmware file.
If the firmware file is missing or fails to parse, the driver falls
back to using the default configuration list for writing the settings.

Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
---
Changes in v2:
- Removed unnecessary null checks for firmware loading logic and ensured consistent return values.
- Adjusted code formatting and indentation to comply with Linux kernel coding standards.
- Enhanced error handling: clearly notify users about firmware loading failures through logs.
- Removed unrelated CC recipients.
- Link to v1: https://lore.kernel.org/r/20241210-hx9023s-firmware-20241209-v1-1-8a736691b106@gmail.com
---
 drivers/iio/proximity/hx9023s.c | 93 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 86 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/proximity/hx9023s.c b/drivers/iio/proximity/hx9023s.c
index 4021feb7a7ac..d5b1522d3c19 100644
--- a/drivers/iio/proximity/hx9023s.c
+++ b/drivers/iio/proximity/hx9023s.c
@@ -14,6 +14,7 @@
 #include <linux/cleanup.h>
 #include <linux/device.h>
 #include <linux/errno.h>
+#include <linux/firmware.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/irqreturn.h>
@@ -100,6 +101,17 @@
 #define HX9023S_INTERRUPT_MASK GENMASK(9, 0)
 #define HX9023S_PROX_DEBOUNCE_MASK GENMASK(3, 0)
 
+#define FW_VER_OFFSET 2
+#define FW_REG_CNT_OFFSET 3
+#define FW_DATA_OFFSET 16
+
+struct hx9023s_bin {
+	u16 reg_count;
+	u16 fw_size;
+	u8 fw_ver;
+	u8 data[] __counted_by(fw_size);
+};
+
 struct hx9023s_ch_data {
 	s16 raw; /* Raw Data*/
 	s16 lp; /* Low Pass Filter Data*/
@@ -998,6 +1010,77 @@ static int hx9023s_id_check(struct iio_dev *indio_dev)
 	return 0;
 }
 
+static int hx9023s_bin_load(struct hx9023s_data *data, struct hx9023s_bin *bin)
+{
+	u8 *cfg_start = bin->data + FW_DATA_OFFSET;
+	u8 addr, val;
+	u16 i;
+	int ret;
+
+	for (i = 0; i < bin->reg_count; i++) {
+		addr = cfg_start[i * 2];
+		val = cfg_start[i * 2 + 1];
+		ret = regmap_write(data->regmap, addr, val);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int hx9023s_send_cfg(const struct firmware *fw, struct hx9023s_data *data)
+{
+	struct hx9023s_bin *bin __free(kfree) =
+		kzalloc(fw->size + sizeof(*bin), GFP_KERNEL);
+	if (!bin)
+		return -ENOMEM;
+
+	memcpy(bin->data, fw->data, fw->size);
+	release_firmware(fw);
+
+	bin->fw_size = fw->size;
+	bin->fw_ver = bin->data[FW_VER_OFFSET];
+	bin->reg_count = get_unaligned_le16(bin->data + FW_REG_CNT_OFFSET);
+
+	return hx9023s_bin_load(data, bin);
+}
+
+static void hx9023s_cfg_update(const struct firmware *fw, void *context)
+{
+	struct hx9023s_data *data = context;
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+
+	if (!fw || !fw->data) {
+		dev_warn(dev, "No firmware\n");
+		goto no_fw;
+	}
+
+	ret = hx9023s_send_cfg(fw, data);
+	if (ret) {
+		dev_warn(dev, "Firmware update failed: %d\n", ret);
+		goto no_fw;
+	}
+
+	ret = regcache_sync(data->regmap);
+	if (ret)
+		dev_err(dev, "regcache sync failed\n");
+
+	return;
+
+no_fw:
+	ret = regmap_multi_reg_write(data->regmap, hx9023s_reg_init_list,
+				     ARRAY_SIZE(hx9023s_reg_init_list));
+	if (ret) {
+		dev_err(dev, "Error loading default configuration\n");
+		return;
+	}
+
+	ret = regcache_sync(data->regmap);
+	if (ret)
+		dev_err(dev, "regcache sync failed\n");
+}
+
 static int hx9023s_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -1036,18 +1119,14 @@ static int hx9023s_probe(struct i2c_client *client)
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	i2c_set_clientdata(client, indio_dev);
 
-	ret = regmap_multi_reg_write(data->regmap, hx9023s_reg_init_list,
-				     ARRAY_SIZE(hx9023s_reg_init_list));
-	if (ret)
-		return dev_err_probe(dev, ret, "device init failed\n");
-
 	ret = hx9023s_ch_cfg(data);
 	if (ret)
 		return dev_err_probe(dev, ret, "channel config failed\n");
 
-	ret = regcache_sync(data->regmap);
+	ret = request_firmware_nowait(THIS_MODULE, true, "hx9023s.bin", dev,
+				      GFP_KERNEL, data, hx9023s_cfg_update);
 	if (ret)
-		return dev_err_probe(dev, ret, "regcache sync failed\n");
+		return dev_err_probe(dev, ret, "reg config failed\n");
 
 	if (client->irq) {
 		ret = devm_request_threaded_irq(dev, client->irq,

---
base-commit: 8d4d26450d71289a35ff9e847675fd9c718798b8
change-id: 20241209-hx9023s-firmware-20241209-47411e8cda0b

Best regards,
-- 
Yasin Lee <yasin.lee.x@gmail.com>

On Mon, 16 Dec 2024 15:59:40 +0800
Yasin Lee <yasin.lee.x@gmail.com> wrote:

> Configuration information is now prioritized from the firmware file.
> If the firmware file is missing or fails to parse, the driver falls
> back to using the default configuration list for writing the settings.
> 
> Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>

Applied to the togreg branch of iio.git and pushed out as testing for 0-day
to take a look at it.

Thanks,

Jonathan