[PATCH REVIEW] e4000: convert DVB tuner to I2C driver model

[Antti Palosaari <crope@iki.fi>]

Initial driver conversion from proprietary DVB tuner model to more
general I2C driver model.

That commit has just basic binding stuff and driver itself still
needs to be converted more complete later.

Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Antti Palosaari <crope@iki.fi>
---
 drivers/media/tuners/e4000.c            | 73 ++++++++++++++++++++++-----------
 drivers/media/tuners/e4000.h            |  9 +++-
 drivers/media/tuners/e4000_priv.h       |  4 +-
 drivers/media/usb/dvb-usb-v2/rtl28xxu.c | 31 +++++++++-----
 4 files changed, 78 insertions(+), 39 deletions(-)

diff --git a/drivers/media/tuners/e4000.c b/drivers/media/tuners/e4000.c
index 54e2d8a..f6a5dbd 100644
--- a/drivers/media/tuners/e4000.c
+++ b/drivers/media/tuners/e4000.c
@@ -27,7 +27,7 @@ static int e4000_wr_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
 	u8 buf[1 + len];
 	struct i2c_msg msg[1] = {
 		{
-			.addr = priv->cfg->i2c_addr,
+			.addr = priv->i2c_addr,
 			.flags = 0,
 			.len = sizeof(buf),
 			.buf = buf,
@@ -56,12 +56,12 @@ static int e4000_rd_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
 	u8 buf[len];
 	struct i2c_msg msg[2] = {
 		{
-			.addr = priv->cfg->i2c_addr,
+			.addr = priv->i2c_addr,
 			.flags = 0,
 			.len = 1,
 			.buf = &reg,
 		}, {
-			.addr = priv->cfg->i2c_addr,
+			.addr = priv->i2c_addr,
 			.flags = I2C_M_RD,
 			.len = sizeof(buf),
 			.buf = buf,
@@ -233,8 +233,8 @@ static int e4000_set_params(struct dvb_frontend *fe)
 	 * or more.
 	 */
 	f_vco = c->frequency * e4000_pll_lut[i].mul;
-	sigma_delta = div_u64(0x10000ULL * (f_vco % priv->cfg->clock), priv->cfg->clock);
-	buf[0] = f_vco / priv->cfg->clock;
+	sigma_delta = div_u64(0x10000ULL * (f_vco % priv->clock), priv->clock);
+	buf[0] = f_vco / priv->clock;
 	buf[1] = (sigma_delta >> 0) & 0xff;
 	buf[2] = (sigma_delta >> 8) & 0xff;
 	buf[3] = 0x00;
@@ -358,17 +358,6 @@ static int e4000_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
 	return 0;
 }
 
-static int e4000_release(struct dvb_frontend *fe)
-{
-	struct e4000_priv *priv = fe->tuner_priv;
-
-	dev_dbg(&priv->i2c->dev, "%s:\n", __func__);
-
-	kfree(fe->tuner_priv);
-
-	return 0;
-}
-
 static const struct dvb_tuner_ops e4000_tuner_ops = {
 	.info = {
 		.name           = "Elonics E4000",
@@ -376,8 +365,6 @@ static const struct dvb_tuner_ops e4000_tuner_ops = {
 		.frequency_max  = 862000000,
 	},
 
-	.release = e4000_release,
-
 	.init = e4000_init,
 	.sleep = e4000_sleep,
 	.set_params = e4000_set_params,
@@ -385,9 +372,12 @@ static const struct dvb_tuner_ops e4000_tuner_ops = {
 	.get_if_frequency = e4000_get_if_frequency,
 };
 
-struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
-		struct i2c_adapter *i2c, const struct e4000_config *cfg)
+static int e4000_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
 {
+	struct e4000_config *cfg = client->dev.platform_data;
+	struct dvb_frontend *fe = cfg->fe;
+	struct i2c_adapter *i2c = client->adapter;
 	struct e4000_priv *priv;
 	int ret;
 	u8 chip_id;
@@ -402,7 +392,9 @@ struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
 		goto err;
 	}
 
-	priv->cfg = cfg;
+	priv->i2c_addr = cfg->i2c_addr;
+	priv->clock = cfg->clock;
+	priv->i2c_client = client;
 	priv->i2c = i2c;
 
 	/* check if the tuner is there */
@@ -412,8 +404,10 @@ struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
 
 	dev_dbg(&priv->i2c->dev, "%s: chip_id=%02x\n", __func__, chip_id);
 
-	if (chip_id != 0x40)
+	if (chip_id != 0x40) {
+		ret = -ENODEV;
 		goto err;
+	}
 
 	/* put sleep as chip seems to be in normal mode by default */
 	ret = e4000_wr_reg(priv, 0x00, 0x00);
@@ -431,16 +425,45 @@ struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 0);
 
-	return fe;
+	i2c_set_clientdata(client, priv);
+
+	return 0;
 err:
 	if (fe->ops.i2c_gate_ctrl)
 		fe->ops.i2c_gate_ctrl(fe, 0);
 
 	dev_dbg(&i2c->dev, "%s: failed=%d\n", __func__, ret);
 	kfree(priv);
-	return NULL;
+	return ret;
 }
-EXPORT_SYMBOL(e4000_attach);
+
+static int e4000_remove(struct i2c_client *client)
+{
+	struct e4000_priv *priv = i2c_get_clientdata(client);
+
+	dev_dbg(&client->dev, "%s:\n", __func__);
+
+	kfree(priv);
+	return 0;
+}
+
+static const struct i2c_device_id e4000_id[] = {
+	{"e4000", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, e4000_id);
+
+static struct i2c_driver e4000_driver = {
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= "e4000",
+	},
+	.probe		= e4000_probe,
+	.remove		= e4000_remove,
+	.id_table	= e4000_id,
+};
+
+module_i2c_driver(e4000_driver);
 
 MODULE_DESCRIPTION("Elonics E4000 silicon tuner driver");
 MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
diff --git a/drivers/media/tuners/e4000.h b/drivers/media/tuners/e4000.h
index 25ee7c0..760b206 100644
--- a/drivers/media/tuners/e4000.h
+++ b/drivers/media/tuners/e4000.h
@@ -26,6 +26,11 @@
 
 struct e4000_config {
 	/*
+	 * frontend
+	 */
+	struct dvb_frontend *fe;
+
+	/*
 	 * I2C address
 	 * 0x64, 0x65, 0x66, 0x67
 	 */
@@ -39,10 +44,10 @@ struct e4000_config {
 
 #if IS_ENABLED(CONFIG_MEDIA_TUNER_E4000)
 extern struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
-		struct i2c_adapter *i2c, const struct e4000_config *cfg);
+		struct i2c_adapter *i2c, struct e4000_config *cfg);
 #else
 static inline struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
-		struct i2c_adapter *i2c, const struct e4000_config *cfg)
+		struct i2c_adapter *i2c, struct e4000_config *cfg)
 {
 	dev_warn(&i2c->dev, "%s: driver disabled by Kconfig\n", __func__);
 	return NULL;
diff --git a/drivers/media/tuners/e4000_priv.h b/drivers/media/tuners/e4000_priv.h
index a385505..7f47068 100644
--- a/drivers/media/tuners/e4000_priv.h
+++ b/drivers/media/tuners/e4000_priv.h
@@ -24,8 +24,10 @@
 #include "e4000.h"
 
 struct e4000_priv {
-	const struct e4000_config *cfg;
 	struct i2c_adapter *i2c;
+	struct i2c_client *i2c_client;
+	u8 i2c_addr;
+	u32 clock;
 };
 
 struct e4000_pll {
diff --git a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
index defc491..573805a 100644
--- a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
+++ b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
@@ -843,11 +843,6 @@ err:
 	return ret;
 }
 
-static const struct e4000_config rtl2832u_e4000_config = {
-	.i2c_addr = 0x64,
-	.clock = 28800000,
-};
-
 static const struct fc2580_config rtl2832u_fc2580_config = {
 	.i2c_addr = 0x56,
 	.clock = 16384000,
@@ -874,10 +869,14 @@ static int rtl2832u_tuner_attach(struct dvb_usb_adapter *adap)
 	int ret;
 	struct dvb_usb_device *d = adap_to_d(adap);
 	struct rtl28xxu_priv *priv = d_to_priv(d);
-	struct dvb_frontend *fe;
+	struct dvb_frontend *fe = NULL;
+	struct i2c_client *client = NULL;
+	struct i2c_board_info info;
 
 	dev_dbg(&d->udev->dev, "%s:\n", __func__);
 
+	memset(&info, 0, sizeof(struct i2c_board_info));
+
 	switch (priv->tuner) {
 	case TUNER_RTL2832_FC0012:
 		fe = dvb_attach(fc0012_attach, adap->fe[0],
@@ -897,9 +896,20 @@ static int rtl2832u_tuner_attach(struct dvb_usb_adapter *adap)
 		adap->fe[0]->ops.read_signal_strength =
 				adap->fe[0]->ops.tuner_ops.get_rf_strength;
 		return 0;
-	case TUNER_RTL2832_E4000:
-		fe = dvb_attach(e4000_attach, adap->fe[0], &d->i2c_adap,
-				&rtl2832u_e4000_config);
+	case TUNER_RTL2832_E4000: {
+			struct e4000_config e4000_config = {
+				.fe = adap->fe[0],
+				.i2c_addr = 0x64,
+				.clock = 28800000,
+			};
+
+			strlcpy(info.type, "e4000", I2C_NAME_SIZE);
+			info.addr = 0x64;
+			info.platform_data = &e4000_config;
+
+			request_module("e4000");
+			client = i2c_new_device(&d->i2c_adap, &info);
+		}
 		break;
 	case TUNER_RTL2832_FC2580:
 		fe = dvb_attach(fc2580_attach, adap->fe[0], &d->i2c_adap,
@@ -927,12 +937,11 @@ static int rtl2832u_tuner_attach(struct dvb_usb_adapter *adap)
 				adap->fe[0]->ops.tuner_ops.get_rf_strength;
 		break;
 	default:
-		fe = NULL;
 		dev_err(&d->udev->dev, "%s: unknown tuner=%d\n", KBUILD_MODNAME,
 				priv->tuner);
 	}
 
-	if (fe == NULL) {
+	if (fe == NULL && (client == NULL || client->driver == NULL)) {
 		ret = -ENODEV;
 		goto err;
 	}
-- 
1.8.3.1