linux/drivers/media/tuners/tda18212.c
Mauro Carvalho Chehab f1baab870f [media] tuners: Don't use dynamic static allocation
Dynamic static allocation is evil, as Kernel stack is too low, and
compilation complains about it on some archs:
	drivers/media/tuners/e4000.c:50:1: warning: 'e4000_wr_regs' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/e4000.c:83:1: warning: 'e4000_rd_regs' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/fc2580.c:66:1: warning: 'fc2580_wr_regs.constprop.1' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/fc2580.c:98:1: warning: 'fc2580_rd_regs.constprop.0' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/tda18212.c:57:1: warning: 'tda18212_wr_regs' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/tda18212.c:90:1: warning: 'tda18212_rd_regs.constprop.0' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/tda18218.c:60:1: warning: 'tda18218_wr_regs' uses dynamic stack allocation [enabled by default]
	drivers/media/tuners/tda18218.c:92:1: warning: 'tda18218_rd_regs.constprop.0' uses dynamic stack allocation [enabled by default]
Instead, let's enforce a limit for the buffer. Considering that I2C
transfers are generally limited, and that devices used on USB has a
max data length of 64 bytes for	the control URBs.
So, it seem safe to use 64 bytes as the hard limit for all those devices.
 On most cases, the limit is a way lower than that, but	this limit
is small enough to not affect the Kernel stack, and it is a no brain
limit, as using smaller ones would require to either carefully each
driver or to take a look on each datasheet.

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-11-08 09:45:41 -02:00

337 lines
7.4 KiB
C

/*
* NXP TDA18212HN silicon tuner driver
*
* Copyright (C) 2011 Antti Palosaari <crope@iki.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "tda18212.h"
/* Max transfer size done by I2C transfer functions */
#define MAX_XFER_SIZE 64
struct tda18212_priv {
struct tda18212_config *cfg;
struct i2c_adapter *i2c;
u32 if_frequency;
};
/* write multiple registers */
static int tda18212_wr_regs(struct tda18212_priv *priv, u8 reg, u8 *val,
int len)
{
int ret;
u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[1] = {
{
.addr = priv->cfg->i2c_address,
.flags = 0,
.len = 1 + len,
.buf = buf,
}
};
if (1 + len > sizeof(buf)) {
dev_warn(&priv->i2c->dev,
"%s: i2c wr reg=%04x: len=%d is too big!\n",
KBUILD_MODNAME, reg, len);
return -EINVAL;
}
buf[0] = reg;
memcpy(&buf[1], val, len);
ret = i2c_transfer(priv->i2c, msg, 1);
if (ret == 1) {
ret = 0;
} else {
dev_warn(&priv->i2c->dev, "%s: i2c wr failed=%d reg=%02x " \
"len=%d\n", KBUILD_MODNAME, ret, reg, len);
ret = -EREMOTEIO;
}
return ret;
}
/* read multiple registers */
static int tda18212_rd_regs(struct tda18212_priv *priv, u8 reg, u8 *val,
int len)
{
int ret;
u8 buf[MAX_XFER_SIZE];
struct i2c_msg msg[2] = {
{
.addr = priv->cfg->i2c_address,
.flags = 0,
.len = 1,
.buf = &reg,
}, {
.addr = priv->cfg->i2c_address,
.flags = I2C_M_RD,
.len = len,
.buf = buf,
}
};
if (len > sizeof(buf)) {
dev_warn(&priv->i2c->dev,
"%s: i2c rd reg=%04x: len=%d is too big!\n",
KBUILD_MODNAME, reg, len);
return -EINVAL;
}
ret = i2c_transfer(priv->i2c, msg, 2);
if (ret == 2) {
memcpy(val, buf, len);
ret = 0;
} else {
dev_warn(&priv->i2c->dev, "%s: i2c rd failed=%d reg=%02x " \
"len=%d\n", KBUILD_MODNAME, ret, reg, len);
ret = -EREMOTEIO;
}
return ret;
}
/* write single register */
static int tda18212_wr_reg(struct tda18212_priv *priv, u8 reg, u8 val)
{
return tda18212_wr_regs(priv, reg, &val, 1);
}
/* read single register */
static int tda18212_rd_reg(struct tda18212_priv *priv, u8 reg, u8 *val)
{
return tda18212_rd_regs(priv, reg, val, 1);
}
#if 0 /* keep, useful when developing driver */
static void tda18212_dump_regs(struct tda18212_priv *priv)
{
int i;
u8 buf[256];
#define TDA18212_RD_LEN 32
for (i = 0; i < sizeof(buf); i += TDA18212_RD_LEN)
tda18212_rd_regs(priv, i, &buf[i], TDA18212_RD_LEN);
print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 32, 1, buf,
sizeof(buf), true);
return;
}
#endif
static int tda18212_set_params(struct dvb_frontend *fe)
{
struct tda18212_priv *priv = fe->tuner_priv;
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
int ret, i;
u32 if_khz;
u8 buf[9];
#define DVBT_6 0
#define DVBT_7 1
#define DVBT_8 2
#define DVBT2_6 3
#define DVBT2_7 4
#define DVBT2_8 5
#define DVBC_6 6
#define DVBC_8 7
static const u8 bw_params[][3] = {
/* reg: 0f 13 23 */
[DVBT_6] = { 0xb3, 0x20, 0x03 },
[DVBT_7] = { 0xb3, 0x31, 0x01 },
[DVBT_8] = { 0xb3, 0x22, 0x01 },
[DVBT2_6] = { 0xbc, 0x20, 0x03 },
[DVBT2_7] = { 0xbc, 0x72, 0x03 },
[DVBT2_8] = { 0xbc, 0x22, 0x01 },
[DVBC_6] = { 0x92, 0x50, 0x03 },
[DVBC_8] = { 0x92, 0x53, 0x03 },
};
dev_dbg(&priv->i2c->dev,
"%s: delivery_system=%d frequency=%d bandwidth_hz=%d\n",
__func__, c->delivery_system, c->frequency,
c->bandwidth_hz);
if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */
switch (c->delivery_system) {
case SYS_DVBT:
switch (c->bandwidth_hz) {
case 6000000:
if_khz = priv->cfg->if_dvbt_6;
i = DVBT_6;
break;
case 7000000:
if_khz = priv->cfg->if_dvbt_7;
i = DVBT_7;
break;
case 8000000:
if_khz = priv->cfg->if_dvbt_8;
i = DVBT_8;
break;
default:
ret = -EINVAL;
goto error;
}
break;
case SYS_DVBT2:
switch (c->bandwidth_hz) {
case 6000000:
if_khz = priv->cfg->if_dvbt2_6;
i = DVBT2_6;
break;
case 7000000:
if_khz = priv->cfg->if_dvbt2_7;
i = DVBT2_7;
break;
case 8000000:
if_khz = priv->cfg->if_dvbt2_8;
i = DVBT2_8;
break;
default:
ret = -EINVAL;
goto error;
}
break;
case SYS_DVBC_ANNEX_A:
case SYS_DVBC_ANNEX_C:
if_khz = priv->cfg->if_dvbc;
i = DVBC_8;
break;
default:
ret = -EINVAL;
goto error;
}
ret = tda18212_wr_reg(priv, 0x23, bw_params[i][2]);
if (ret)
goto error;
ret = tda18212_wr_reg(priv, 0x06, 0x00);
if (ret)
goto error;
ret = tda18212_wr_reg(priv, 0x0f, bw_params[i][0]);
if (ret)
goto error;
buf[0] = 0x02;
buf[1] = bw_params[i][1];
buf[2] = 0x03; /* default value */
buf[3] = DIV_ROUND_CLOSEST(if_khz, 50);
buf[4] = ((c->frequency / 1000) >> 16) & 0xff;
buf[5] = ((c->frequency / 1000) >> 8) & 0xff;
buf[6] = ((c->frequency / 1000) >> 0) & 0xff;
buf[7] = 0xc1;
buf[8] = 0x01;
ret = tda18212_wr_regs(priv, 0x12, buf, sizeof(buf));
if (ret)
goto error;
/* actual IF rounded as it is on register */
priv->if_frequency = buf[3] * 50 * 1000;
exit:
if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
return ret;
error:
dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);
goto exit;
}
static int tda18212_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
{
struct tda18212_priv *priv = fe->tuner_priv;
*frequency = priv->if_frequency;
return 0;
}
static int tda18212_release(struct dvb_frontend *fe)
{
kfree(fe->tuner_priv);
fe->tuner_priv = NULL;
return 0;
}
static const struct dvb_tuner_ops tda18212_tuner_ops = {
.info = {
.name = "NXP TDA18212",
.frequency_min = 48000000,
.frequency_max = 864000000,
.frequency_step = 1000,
},
.release = tda18212_release,
.set_params = tda18212_set_params,
.get_if_frequency = tda18212_get_if_frequency,
};
struct dvb_frontend *tda18212_attach(struct dvb_frontend *fe,
struct i2c_adapter *i2c, struct tda18212_config *cfg)
{
struct tda18212_priv *priv = NULL;
int ret;
u8 val;
priv = kzalloc(sizeof(struct tda18212_priv), GFP_KERNEL);
if (priv == NULL)
return NULL;
priv->cfg = cfg;
priv->i2c = i2c;
fe->tuner_priv = priv;
if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */
/* check if the tuner is there */
ret = tda18212_rd_reg(priv, 0x00, &val);
if (fe->ops.i2c_gate_ctrl)
fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
if (!ret)
dev_dbg(&priv->i2c->dev, "%s: chip id=%02x\n", __func__, val);
if (ret || val != 0xc7) {
kfree(priv);
return NULL;
}
dev_info(&priv->i2c->dev,
"%s: NXP TDA18212HN successfully identified\n",
KBUILD_MODNAME);
memcpy(&fe->ops.tuner_ops, &tda18212_tuner_ops,
sizeof(struct dvb_tuner_ops));
return fe;
}
EXPORT_SYMBOL(tda18212_attach);
MODULE_DESCRIPTION("NXP TDA18212HN silicon tuner driver");
MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
MODULE_LICENSE("GPL");