[PATCH v3 1/2] iio: adc: mcp3422: describe parts with chip_info

[Yuval Saar <thefireking@gmail.com>]

The driver encodes MCP3421-8 differences as integer ids and switches
on them in probe. Point i2c_device_id.driver_data at a per-chip
structure instead, and keep the channel list and 3 SPS support there.

Compile tested. No hardware.

Assisted-by: LLM
Signed-off-by: Yuval Saar <thefireking@gmail.com>
---
 drivers/iio/adc/mcp3422.c | 103 ++++++++++++++++++++++++++------------
 1 file changed, 70 insertions(+), 33 deletions(-)

diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c
index 36ba00edf..92825aaf2 100644
--- a/drivers/iio/adc/mcp3422.c
+++ b/drivers/iio/adc/mcp3422.c
@@ -76,10 +76,16 @@ static const int mcp3422_sign_extend[4] = {
 	[MCP3422_SRATE_15] = 15,
 	[MCP3422_SRATE_3] = 17 };
 
+struct mcp3422_chip_info {
+	const struct iio_chan_spec *channels;
+	unsigned int num_channels;
+	bool supports_3sps;
+};
+
 /* Client data (each client gets its own) */
 struct mcp3422 {
 	struct i2c_client *i2c;
-	u8 id;
+	const struct mcp3422_chip_info *chip_info;
 	u8 config;
 	u8 pga[4];
 	struct mutex lock;
@@ -223,7 +229,7 @@ static int mcp3422_write_raw(struct iio_dev *iio,
 			temp = MCP3422_SRATE_15;
 			break;
 		case 3:
-			if (adc->id > 4)
+			if (!adc->chip_info->supports_3sps)
 				return -EINVAL;
 			temp = MCP3422_SRATE_3;
 			break;
@@ -261,7 +267,7 @@ static ssize_t mcp3422_show_samp_freqs(struct device *dev,
 {
 	struct mcp3422 *adc = iio_priv(dev_to_iio_dev(dev));
 
-	if (adc->id > 4)
+	if (!adc->chip_info->supports_3sps)
 		return sprintf(buf, "240 60 15\n");
 
 	return sprintf(buf, "240 60 15 3\n");
@@ -311,6 +317,54 @@ static const struct iio_chan_spec mcp3424_channels[] = {
 	MCP3422_CHAN(3),
 };
 
+static const struct mcp3422_chip_info mcp3421_chip_info = {
+	.channels = mcp3421_channels,
+	.num_channels = ARRAY_SIZE(mcp3421_channels),
+	.supports_3sps = true,
+};
+
+static const struct mcp3422_chip_info mcp3422_chip_info = {
+	.channels = mcp3422_channels,
+	.num_channels = ARRAY_SIZE(mcp3422_channels),
+	.supports_3sps = true,
+};
+
+static const struct mcp3422_chip_info mcp3423_chip_info = {
+	.channels = mcp3422_channels,
+	.num_channels = ARRAY_SIZE(mcp3422_channels),
+	.supports_3sps = true,
+};
+
+static const struct mcp3422_chip_info mcp3424_chip_info = {
+	.channels = mcp3424_channels,
+	.num_channels = ARRAY_SIZE(mcp3424_channels),
+	.supports_3sps = true,
+};
+
+static const struct mcp3422_chip_info mcp3425_chip_info = {
+	.channels = mcp3421_channels,
+	.num_channels = ARRAY_SIZE(mcp3421_channels),
+	.supports_3sps = false,
+};
+
+static const struct mcp3422_chip_info mcp3426_chip_info = {
+	.channels = mcp3422_channels,
+	.num_channels = ARRAY_SIZE(mcp3422_channels),
+	.supports_3sps = false,
+};
+
+static const struct mcp3422_chip_info mcp3427_chip_info = {
+	.channels = mcp3422_channels,
+	.num_channels = ARRAY_SIZE(mcp3422_channels),
+	.supports_3sps = false,
+};
+
+static const struct mcp3422_chip_info mcp3428_chip_info = {
+	.channels = mcp3424_channels,
+	.num_channels = ARRAY_SIZE(mcp3424_channels),
+	.supports_3sps = false,
+};
+
 static const struct iio_info mcp3422_info = {
 	.read_raw = mcp3422_read_raw,
 	.write_raw = mcp3422_write_raw,
@@ -320,7 +374,6 @@ static const struct iio_info mcp3422_info = {
 
 static int mcp3422_probe(struct i2c_client *client)
 {
-	const struct i2c_device_id *id = i2c_client_get_device_id(client);
 	struct iio_dev *indio_dev;
 	struct mcp3422 *adc;
 	int err;
@@ -335,33 +388,17 @@ static int mcp3422_probe(struct i2c_client *client)
 
 	adc = iio_priv(indio_dev);
 	adc->i2c = client;
-	adc->id = (u8)(id->driver_data);
+	adc->chip_info = i2c_get_match_data(client);
+	if (!adc->chip_info)
+		return -ENODEV;
 
 	mutex_init(&adc->lock);
 
 	indio_dev->name = dev_name(&client->dev);
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &mcp3422_info;
-
-	switch (adc->id) {
-	case 1:
-	case 5:
-		indio_dev->channels = mcp3421_channels;
-		indio_dev->num_channels = ARRAY_SIZE(mcp3421_channels);
-		break;
-	case 2:
-	case 3:
-	case 6:
-	case 7:
-		indio_dev->channels = mcp3422_channels;
-		indio_dev->num_channels = ARRAY_SIZE(mcp3422_channels);
-		break;
-	case 4:
-	case 8:
-		indio_dev->channels = mcp3424_channels;
-		indio_dev->num_channels = ARRAY_SIZE(mcp3424_channels);
-		break;
-	}
+	indio_dev->channels = adc->chip_info->channels;
+	indio_dev->num_channels = adc->chip_info->num_channels;
 
 	/* meaningful default configuration */
 	config = MCP3422_CONT_SAMPLING |
@@ -382,14 +419,14 @@ static int mcp3422_probe(struct i2c_client *client)
 }
 
 static const struct i2c_device_id mcp3422_id[] = {
-	{ .name = "mcp3421", .driver_data = 1 },
-	{ .name = "mcp3422", .driver_data = 2 },
-	{ .name = "mcp3423", .driver_data = 3 },
-	{ .name = "mcp3424", .driver_data = 4 },
-	{ .name = "mcp3425", .driver_data = 5 },
-	{ .name = "mcp3426", .driver_data = 6 },
-	{ .name = "mcp3427", .driver_data = 7 },
-	{ .name = "mcp3428", .driver_data = 8 },
+	{ .name = "mcp3421", .driver_data = (kernel_ulong_t)&mcp3421_chip_info },
+	{ .name = "mcp3422", .driver_data = (kernel_ulong_t)&mcp3422_chip_info },
+	{ .name = "mcp3423", .driver_data = (kernel_ulong_t)&mcp3423_chip_info },
+	{ .name = "mcp3424", .driver_data = (kernel_ulong_t)&mcp3424_chip_info },
+	{ .name = "mcp3425", .driver_data = (kernel_ulong_t)&mcp3425_chip_info },
+	{ .name = "mcp3426", .driver_data = (kernel_ulong_t)&mcp3426_chip_info },
+	{ .name = "mcp3427", .driver_data = (kernel_ulong_t)&mcp3427_chip_info },
+	{ .name = "mcp3428", .driver_data = (kernel_ulong_t)&mcp3428_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, mcp3422_id);
-- 
2.43.0