[PATCH v1] media: si2168: Refactor command setup code

From: Marc Gonzalez
Date: Mon Jul 01 2019 - 07:44:15 EST

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Next in thread: Marc Gonzalez: "Re: [PATCH v1] media: si2168: Refactor command setup code"
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By refactoring the command setup code, we can let the compiler
determine the size of each command.

Signed-off-by: Marc Gonzalez <marc.w.gonzalez@xxxxxxx>
---
drivers/media/dvb-frontends/si2168.c | 142 ++++++++-------------------
1 file changed, 41 insertions(+), 101 deletions(-)

diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c
index 168c503e9154..19398f041c79 100644
--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -11,6 +11,12 @@

static const struct dvb_frontend_ops si2168_ops;

+#define CMD_SETUP(cmd, __args, __rlen) do { \
+ int wlen = sizeof(__args) - 1; \
+ memcpy(cmd.args, __args, wlen); \
+ cmd.wlen = wlen; cmd.rlen = __rlen; \
+} while (0)
+
/* execute firmware command */
static int si2168_cmd_execute(struct i2c_client *client, struct si2168_cmd *cmd)
{
@@ -83,15 +89,13 @@ static int si2168_ts_bus_ctrl(struct dvb_frontend *fe, int acquire)
dev_dbg(&client->dev, "%s acquire: %d\n", __func__, acquire);

/* set TS_MODE property */
- memcpy(cmd.args, "\x14\x00\x01\x10\x10\x00", 6);
+ CMD_SETUP(cmd, "\x14\x00\x01\x10\x10\x00", 4);
if (acquire)
cmd.args[4] |= dev->ts_mode;
else
cmd.args[4] |= SI2168_TS_TRISTATE;
if (dev->ts_clock_gapped)
cmd.args[4] |= 0x40;
- cmd.wlen = 6;
- cmd.rlen = 4;
ret = si2168_cmd_execute(client, &cmd);

return ret;
@@ -115,19 +119,13 @@ static int si2168_read_status(struct dvb_frontend *fe, enum fe_status *status)

switch (c->delivery_system) {
case SYS_DVBT:
- memcpy(cmd.args, "\xa0\x01", 2);
- cmd.wlen = 2;
- cmd.rlen = 13;
+ CMD_SETUP(cmd, "\xa0\x01", 13);
break;
case SYS_DVBC_ANNEX_A:
- memcpy(cmd.args, "\x90\x01", 2);
- cmd.wlen = 2;
- cmd.rlen = 9;
+ CMD_SETUP(cmd, "\x90\x01", 9);
break;
case SYS_DVBT2:
- memcpy(cmd.args, "\x50\x01", 2);
- cmd.wlen = 2;
- cmd.rlen = 14;
+ CMD_SETUP(cmd, "\x50\x01", 14);
break;
default:
ret = -EINVAL;
@@ -164,9 +162,7 @@ static int si2168_read_status(struct dvb_frontend *fe, enum fe_status *status)

/* BER */
if (*status & FE_HAS_VITERBI) {
- memcpy(cmd.args, "\x82\x00", 2);
- cmd.wlen = 2;
- cmd.rlen = 3;
+ CMD_SETUP(cmd, "\x82\x00", 3);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -197,9 +193,7 @@ static int si2168_read_status(struct dvb_frontend *fe, enum fe_status *status)

/* UCB */
if (*status & FE_HAS_SYNC) {
- memcpy(cmd.args, "\x84\x01", 2);
- cmd.wlen = 2;
- cmd.rlen = 3;
+ CMD_SETUP(cmd, "\x84\x01", 3);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -285,22 +279,18 @@ static int si2168_set_frontend(struct dvb_frontend *fe)
goto err;
}

- memcpy(cmd.args, "\x88\x02\x02\x02\x02", 5);
- cmd.wlen = 5;
- cmd.rlen = 5;
+ CMD_SETUP(cmd, "\x88\x02\x02\x02\x02", 5);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

/* that has no big effect */
if (c->delivery_system == SYS_DVBT)
- memcpy(cmd.args, "\x89\x21\x06\x11\xff\x98", 6);
+ CMD_SETUP(cmd, "\x89\x21\x06\x11\xff\x98", 3);
else if (c->delivery_system == SYS_DVBC_ANNEX_A)
- memcpy(cmd.args, "\x89\x21\x06\x11\x89\xf0", 6);
+ CMD_SETUP(cmd, "\x89\x21\x06\x11\x89\xf0", 3);
else if (c->delivery_system == SYS_DVBT2)
- memcpy(cmd.args, "\x89\x21\x06\x11\x89\x20", 6);
- cmd.wlen = 6;
- cmd.rlen = 3;
+ CMD_SETUP(cmd, "\x89\x21\x06\x11\x89\x20", 3);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -317,103 +307,77 @@ static int si2168_set_frontend(struct dvb_frontend *fe)
goto err;
}

- memcpy(cmd.args, "\x51\x03", 2);
- cmd.wlen = 2;
- cmd.rlen = 12;
+ CMD_SETUP(cmd, "\x51\x03", 12);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x12\x08\x04", 3);
- cmd.wlen = 3;
- cmd.rlen = 3;
+ CMD_SETUP(cmd, "\x12\x08\x04", 3);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x0c\x10\x12\x00", 6);
- cmd.wlen = 6;
- cmd.rlen = 4;
+ CMD_SETUP(cmd, "\x14\x00\x0c\x10\x12\x00", 4);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x06\x10\x24\x00", 6);
- cmd.wlen = 6;
- cmd.rlen = 4;
+ CMD_SETUP(cmd, "\x14\x00\x06\x10\x24\x00", 4);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x07\x10\x00\x24", 6);
- cmd.wlen = 6;
- cmd.rlen = 4;
+ CMD_SETUP(cmd, "\x14\x00\x07\x10\x00\x24", 4);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x0a\x10\x00\x00", 6);
+ CMD_SETUP(cmd, "\x14\x00\x0a\x10\x00\x00", 4);
cmd.args[4] = delivery_system | bandwidth;
if (dev->spectral_inversion)
cmd.args[5] |= 1;
- cmd.wlen = 6;
- cmd.rlen = 4;
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

/* set DVB-C symbol rate */
if (c->delivery_system == SYS_DVBC_ANNEX_A) {
- memcpy(cmd.args, "\x14\x00\x02\x11", 4);
+ CMD_SETUP(cmd, "\x14\x00\x02\x11\x00\x00", 4);
cmd.args[4] = ((c->symbol_rate / 1000) >> 0) & 0xff;
cmd.args[5] = ((c->symbol_rate / 1000) >> 8) & 0xff;
- cmd.wlen = 6;
- cmd.rlen = 4;
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
}

- memcpy(cmd.args, "\x14\x00\x0f\x10\x10\x00", 6);
- cmd.wlen = 6;
- cmd.rlen = 4;
+ CMD_SETUP(cmd, "\x14\x00\x0f\x10\x10\x00", 4);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x09\x10\xe3\x08", 6);
+ CMD_SETUP(cmd, "\x14\x00\x09\x10\xe3\x08", 4);
cmd.args[5] |= dev->ts_clock_inv ? 0x00 : 0x10;
- cmd.wlen = 6;
- cmd.rlen = 4;
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x08\x10\xd7\x05", 6);
+ CMD_SETUP(cmd, "\x14\x00\x08\x10\xd7\x05", 4);
cmd.args[5] |= dev->ts_clock_inv ? 0x00 : 0x10;
- cmd.wlen = 6;
- cmd.rlen = 4;
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x01\x12\x00\x00", 6);
- cmd.wlen = 6;
- cmd.rlen = 4;
+ CMD_SETUP(cmd, "\x14\x00\x01\x12\x00\x00", 4);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x14\x00\x01\x03\x0c\x00", 6);
- cmd.wlen = 6;
- cmd.rlen = 4;
+ CMD_SETUP(cmd, "\x14\x00\x01\x03\x0c\x00", 4);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

- memcpy(cmd.args, "\x85", 1);
- cmd.wlen = 1;
- cmd.rlen = 1;
+ CMD_SETUP(cmd, "\x85", 1);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -443,26 +407,20 @@ static int si2168_init(struct dvb_frontend *fe)
dev_dbg(&client->dev, "\n");

/* initialize */
- memcpy(cmd.args, "\xc0\x12\x00\x0c\x00\x0d\x16\x00\x00\x00\x00\x00\x00", 13);
- cmd.wlen = 13;
- cmd.rlen = 0;
+ CMD_SETUP(cmd, "\xc0\x12\x00\x0c\x00\x0d\x16\x00\x00\x00\x00\x00\x00", 0);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

if (dev->warm) {
/* resume */
- memcpy(cmd.args, "\xc0\x06\x08\x0f\x00\x20\x21\x01", 8);
- cmd.wlen = 8;
- cmd.rlen = 1;
+ CMD_SETUP(cmd, "\xc0\x06\x08\x0f\x00\x20\x21\x01", 1);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

udelay(100);
- memcpy(cmd.args, "\x85", 1);
- cmd.wlen = 1;
- cmd.rlen = 1;
+ CMD_SETUP(cmd, "\x85", 1);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -471,9 +429,7 @@ static int si2168_init(struct dvb_frontend *fe)
}

/* power up */
- memcpy(cmd.args, "\xc0\x06\x01\x0f\x00\x20\x20\x01", 8);
- cmd.wlen = 8;
- cmd.rlen = 1;
+ CMD_SETUP(cmd, "\xc0\x06\x01\x0f\x00\x20\x20\x01", 1);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -541,17 +497,13 @@ static int si2168_init(struct dvb_frontend *fe)

release_firmware(fw);

- memcpy(cmd.args, "\x01\x01", 2);
- cmd.wlen = 2;
- cmd.rlen = 1;
+ CMD_SETUP(cmd, "\x01\x01", 1);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;

/* query firmware version */
- memcpy(cmd.args, "\x11", 1);
- cmd.wlen = 1;
- cmd.rlen = 10;
+ CMD_SETUP(cmd, "\x11", 10);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -609,9 +561,7 @@ static int si2168_sleep(struct dvb_frontend *fe)
if (dev->version > ('B' << 24 | 4 << 16 | 0 << 8 | 11 << 0))
dev->warm = false;

- memcpy(cmd.args, "\x13", 1);
- cmd.wlen = 1;
- cmd.rlen = 0;
+ CMD_SETUP(cmd, "\x13", 0);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -637,9 +587,7 @@ static int si2168_select(struct i2c_mux_core *muxc, u32 chan)
struct si2168_cmd cmd;

/* open I2C gate */
- memcpy(cmd.args, "\xc0\x0d\x01", 3);
- cmd.wlen = 3;
- cmd.rlen = 0;
+ CMD_SETUP(cmd, "\xc0\x0d\x01", 0);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -657,9 +605,7 @@ static int si2168_deselect(struct i2c_mux_core *muxc, u32 chan)
struct si2168_cmd cmd;

/* close I2C gate */
- memcpy(cmd.args, "\xc0\x0d\x00", 3);
- cmd.wlen = 3;
- cmd.rlen = 0;
+ CMD_SETUP(cmd, "\xc0\x0d\x00", 0);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err;
@@ -730,25 +676,19 @@ static int si2168_probe(struct i2c_client *client,
mutex_init(&dev->i2c_mutex);

/* Initialize */
- memcpy(cmd.args, "\xc0\x12\x00\x0c\x00\x0d\x16\x00\x00\x00\x00\x00\x00", 13);
- cmd.wlen = 13;
- cmd.rlen = 0;
+ CMD_SETUP(cmd, "\xc0\x12\x00\x0c\x00\x0d\x16\x00\x00\x00\x00\x00\x00", 0);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err_kfree;

/* Power up */
- memcpy(cmd.args, "\xc0\x06\x01\x0f\x00\x20\x20\x01", 8);
- cmd.wlen = 8;
- cmd.rlen = 1;
+ CMD_SETUP(cmd, "\xc0\x06\x01\x0f\x00\x20\x20\x01", 1);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err_kfree;

/* Query chip revision */
- memcpy(cmd.args, "\x02", 1);
- cmd.wlen = 1;
- cmd.rlen = 13;
+ CMD_SETUP(cmd, "\x02", 13);
ret = si2168_cmd_execute(client, &cmd);
if (ret)
goto err_kfree;
--
2.17.1

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Previous message: Oliver Graute: "[PATCHv2 2/2] arm64: dts: add basic DTS for imx8qm-rom7720-a1 board"
Next in thread: Marc Gonzalez: "Re: [PATCH v1] media: si2168: Refactor command setup code"
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