tda18218: use generic dvb_wr_regs()

---
 drivers/media/common/tuners/tda18218.c      |   69 
+++++---------------------
 drivers/media/common/tuners/tda18218_priv.h |    3 +
 2 files changed, 17 insertions(+), 55 deletions(-)

index aacfe23..fef5560f 100644
@@ -25,46 +25,6 @@ static int debug;
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
 
-/* write multiple registers */
-static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
-{
-	int ret = 0;
-	u8 buf[1+len], quotient, remainder, i, msg_len, msg_len_max;
-	struct i2c_msg msg[1] = {
-		{
-			.addr = priv->cfg->i2c_address,
-			.flags = 0,
-			.buf = buf,
-		}
-	};
-
-	msg_len_max = priv->cfg->i2c_wr_max - 1;
-	quotient = len / msg_len_max;
-	remainder = len % msg_len_max;
-	msg_len = msg_len_max;
-	for (i = 0; (i <= quotient && remainder); i++) {
-		if (i == quotient)  /* set len of the last msg */
-			msg_len = remainder;
-
-		msg[0].len = msg_len + 1;
-		buf[0] = reg + i * msg_len_max;
-		memcpy(&buf[1], &val[i * msg_len_max], msg_len);
-
-		ret = i2c_transfer(priv->i2c, msg, 1);
-		if (ret != 1)
-			break;
-	}
-
-	if (ret == 1) {
-		ret = 0;
-	} else {
-		warn("i2c wr failed ret:%d reg:%02x len:%d", ret, reg, len);
-		ret = -EREMOTEIO;
-	}
-
-	return ret;
-}
-
 /* read multiple registers */
 static int tda18218_rd_regs(struct tda18218_priv *priv, u8 reg, u8 

*val, u8 len)
{
@@ -96,14 +56,7 @@ static int tda18218_rd_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
return ret;
}

-/* write single register */
-static int tda18218_wr_reg(struct tda18218_priv *priv, u8 reg, u8 val) -{
- return tda18218_wr_regs(priv, reg, &val, 1);
-}
-
/* read single register */
-
static int tda18218_rd_reg(struct tda18218_priv *priv, u8 reg, u8 *val) {
return tda18218_rd_regs(priv, reg, val, 1);
@@ -167,7 +120,7 @@ static int tda18218_set_params(struct dvb_frontend *fe,
buf[0] = (priv->regs[R1A_IF1] & ~7) | BP_Filter; /* BP_Filter */ buf[1] = (priv->regs[R1B_IF2] & ~3) | LP_Fc; /* LP_Fc */ buf[2] = priv->regs[R1C_AGC2B];
- ret = tda18218_wr_regs(priv, R1A_IF1, buf, 3);
+ ret = dvb_wr_regs(&priv->i2c_cfg, R1A_IF1, buf, 3);
if (ret)
goto error;

@@ -175,23 +128,23 @@ static int tda18218_set_params(struct dvb_frontend *fe,
buf[1] = (LO_Frac / 1000) >> 4; /* LO_Frac_1 */
buf[2] = (LO_Frac / 1000) << 4 |
(priv->regs[R0C_MD5] & 0x0f); /* LO_Frac_2 */
- ret = tda18218_wr_regs(priv, R0A_MD3, buf, 3);
+ ret = dvb_wr_regs(&priv->i2c_cfg, R0A_MD3, buf, 3);
if (ret)
goto error;

buf[0] = priv->regs[R0F_MD8] | (1 << 6); /* Freq_prog_Start */
- ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
+ ret = dvb_wr_regs(&priv->i2c_cfg, R0F_MD8, buf, 1);
if (ret)
goto error;

buf[0] = priv->regs[R0F_MD8] & ~(1 << 6); /* Freq_prog_Start */
- ret = tda18218_wr_regs(priv, R0F_MD8, buf, 1);
+ ret = dvb_wr_regs(&priv->i2c_cfg, R0F_MD8, buf, 1);
if (ret)
goto error;

/* trigger AGC */
for (i = 0; i < ARRAY_SIZE(agc); i++) {
- ret = tda18218_wr_reg(priv, agc[i][0], agc[i][1]);
+ ret = dvb_wr_reg(&priv->i2c_cfg, agc[i][0], agc[i][1]);
if (ret)
goto error;
}
@@ -215,7 +168,8 @@ static int tda18218_sleep(struct dvb_frontend *fe)
fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

/* standby */
- ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] | (1 << 0));
+ ret = dvb_wr_reg(&priv->i2c_cfg, R17_PD1,
+ priv->regs[R17_PD1] | (1 << 0));

if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
@@ -236,7 +190,8 @@ static int tda18218_init(struct dvb_frontend *fe)
if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */

- ret = tda18218_wr_regs(priv, R00_ID, priv->regs, TDA18218_NUM_REGS);
+ ret = dvb_wr_regs(&priv->i2c_cfg, R00_ID, priv->regs,
+ TDA18218_NUM_REGS);

if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
@@ -292,6 +247,9 @@ struct dvb_frontend *tda18218_attach(struct dvb_frontend *fe,

priv->cfg = cfg;
priv->i2c = i2c;
+ priv->i2c_cfg.adapter = i2c;
+ priv->i2c_cfg.addr = cfg->i2c_address;
+ priv->i2c_cfg.max_wr = cfg->i2c_wr_max;
fe->tuner_priv = priv;

if (fe->ops.i2c_gate_ctrl)
@@ -318,7 +276,8 @@ struct dvb_frontend *tda18218_attach(struct dvb_frontend *fe,
}

/* standby */
- ret = tda18218_wr_reg(priv, R17_PD1, priv->regs[R17_PD1] | (1 << 0));
+ ret = dvb_wr_reg(&priv->i2c_cfg, R17_PD1,
+ priv->regs[R17_PD1] | (1 << 0));
if (ret)
dbg("%s: failed ret:%d", __func__, ret);

index 904e536..72d7277 100644
@@ -23,6 +23,8 @@
 
 #define LOG_PREFIX "tda18218"
 
+#include "dvb_generic.h"
+
 #undef dbg
 #define dbg(f, arg...) \
 	if (debug) \

@@ -99,6 +101,7 @@
 struct tda18218_priv {
 	struct tda18218_config *cfg;
 	struct i2c_adapter *i2c;
+	struct dvb_i2c_cfg i2c_cfg;
 
 	u8 regs[TDA18218_NUM_REGS];
 };

1.7.4.4

You mean AF9013 demod will close it gate automatically after the I2C STOP ? Answer is no.

There are some demods which closes it automatically, like RTL2830, and some may have configuration if close automatically or not. But most common is that gate needs to be opened and closed manually.

In case of automatic gate close it is easiest way to implement own I2C-adapter for demod. There is few such demods drivers already (implementing their own I2C-adapter).

regards
Antti

http://palosaari.fi/

Hello
After today discussion I think at least following configuration options could be possible:

address len, for format msg
register value len, for format msg
max write len, for splitting
max read len, for splitting
option for repeated start, for splitting
conditional error logging
callback for I2C-mux (I2C-gate)
general functions implemented: wr_regs, rd_regs, wr_reg, rd_reg, wr_reg_mask, wr_reg_bits, rd_reg_bits support for register banks?

That's full list of ideas I have as now. At least in first phase I think only basic register reads and writes are enough.

I wonder if Jean could be as main leader of development since he has surely best knowledge about I2C and all possible users. Otherwise, I think I could do it only as linux-media common functionality, because I don't have enough knowledge about other users.

regards
Antti

http://palosaari.fi/

Yes, I suggest starting simple, and adding things later on as they become needed.

I also suggest spelling out "read" and "write", and also don't forget to prefix your public function names to avoid namespace collisions.

If you want it to happen fast, then I suggest that you drive development yourself, and indeed implement it as a common linux-media functionality for now. Later on, once the code has been in place for some time with success, if other subsystems need something similar then we can consider moving the code to i2c-core or some generic i2c helper module.

If you count on me to drive it, I am afraid it will take months, given my current workload and various tasks with a much higher priority than this. I will however be happy to help with code review.

Jean Delvare