This patch fixes the following error messages with a
Terratec Cinergy T Stick Dual RC DVB-T device.
af9013: i2c wr failed=-1 reg=d607 len=1
af9015: command failed:2
af9013: i2c rd failed=-1 reg=d607 len=1
af9015: command failed:1
It implements exclusive access to i2c for only one frontend at a time
through a use-counter that is increased for each af9013_i2c_gate_ctrl-enable
or i2c-read/write and decreased accordingly. The use-counter remains
incremented after af9013_i2c_gate_ctrl-enable until the corresponding
disable.
Debug output was added.
ToDo:
* Replace frontend by adapter (the dual-tuner devices do actually
provide two adapters with one frontend each)
* move af9013_i2c_gate_mutex, locked_fe, af9013_i2c_gate_ctrl_usecnt
to the usb device
---
drivers/media/dvb/frontends/af9013.c | 93 +-
1 files changed, 80 insertions(+), 13 deletions(-)
diff --git a/drivers/media/dvb/frontends/af9013.c
b/drivers/media/dvb/frontends/af9013.c
index 6bcbcf5..ab69585 100644
--- a/drivers/media/dvb/frontends/af9013.c
+++ b/drivers/media/dvb/frontends/af9013.c
@@ -28,6 +28,54 @@ int af9013_debug;
module_param_named(debug, af9013_debug, int, 0644);
MODULE_PARM_DESC(debug, Turn on/off frontend debugging (default:off).);
+static DEFINE_MUTEX(af9013_i2c_gate_mutex);
+static struct dvb_frontend *locked_fe = 0;
+static int af9013_i2c_gate_ctrl_usecnt = 0;
+
+#define GATE_NOOP0
+#define GATE_ENABLE 1
+#define GATE_DISABLE 2
+
+static int af9013_i2c_gate_inc_use_count(struct dvb_frontend *fe, int gate_op)
+{
+ int success = 0;
+ while (1) {
+ if (mutex_lock_interruptible(af9013_i2c_gate_mutex) != 0) {
+ return -EAGAIN;
+ }
+ if (af9013_i2c_gate_ctrl_usecnt == 0 || locked_fe == fe) {
+ success = 1;
+ locked_fe = fe;
+ if (gate_op != GATE_DISABLE) {
+ af9013_i2c_gate_ctrl_usecnt++;
+ }
+ }
+ mutex_unlock(af9013_i2c_gate_mutex);
+ if (success) {
+ break;
+ }
+ schedule();
+ }
+ dbg(%s: %d (%d), __func__, af9013_i2c_gate_ctrl_usecnt, fe-dvb-num);
+ return 0;
+}
+
+static int af9013_i2c_gate_dec_use_count(struct dvb_frontend *fe, int gate_op)
+{
+ if (mutex_lock_interruptible(af9013_i2c_gate_mutex) != 0) {
+ return -EAGAIN;
+ }
+ if (gate_op != GATE_ENABLE) {
+ af9013_i2c_gate_ctrl_usecnt--;
+ }
+ if (af9013_i2c_gate_ctrl_usecnt == 0) {
+ locked_fe = 0;
+ }
+ mutex_unlock(af9013_i2c_gate_mutex);
+ dbg(%s: %d (%d), __func__, af9013_i2c_gate_ctrl_usecnt, fe-dvb-num);
+ return 0;
+}
+
struct af9013_state {
struct i2c_adapter *i2c;
struct dvb_frontend fe;
@@ -44,7 +92,6 @@ struct af9013_state {
unsigned long set_frontend_jiffies;
unsigned long read_status_jiffies;
bool first_tune;
- bool i2c_gate_state;
unsigned int statistics_step:3;
struct delayed_work statistics_work;
};
@@ -54,6 +101,7 @@ static int af9013_wr_regs_i2c(struct af9013_state *priv, u8
mbox, u16 reg,
const u8 *val, int len)
{
int ret;
+ struct dvb_frontend *fe = (priv-fe);
u8 buf[3+len];
struct i2c_msg msg[1] = {
{
@@ -69,6 +117,10 @@ static int af9013_wr_regs_i2c(struct af9013_state *priv, u8
mbox, u16 reg,
buf[2] = mbox;
memcpy(buf[3], val, len);
+ if (af9013_i2c_gate_inc_use_count(fe, GATE_NOOP) != 0) {
+ return -EAGAIN;
+ }
+ dbg(%s: I2C write reg:%04x (%d), __func__, reg, fe-dvb-num);
ret = i2c_transfer(priv-i2c, msg, 1);
if (ret == 1) {
ret = 0;
@@ -76,6 +128,10 @@ static int af9013_wr_regs_i2c(struct af9013_state *priv, u8
mbox, u16 reg,
warn(i2c wr failed=%d reg=%04x len=%d, ret, reg, len);
ret = -EREMOTEIO;
}
+
+ if (af9013_i2c_gate_dec_use_count(fe, GATE_NOOP) != 0) {
+ return -EAGAIN;
+ }
return ret;
}
@@ -84,6 +140,7 @@ static int af9013_rd_regs_i2c(struct af9013_state *priv, u8
mbox, u16 reg,
u8 *val, int len)
{
int ret;
+ struct dvb_frontend *fe = (priv-fe);
u8 buf[3];
struct i2c_msg msg[2] = {
{
@@ -103,6 +160,10 @@ static int af9013_rd_regs_i2c(struct af9013_state *priv,
u8 mbox, u16 reg,
buf[1] = (reg 0) 0xff;
buf[2] = mbox;
+ if (af9013_i2c_gate_inc_use_count(fe, GATE_NOOP) != 0) {
+ return -EAGAIN;
+ }
+ dbg(%s: I2C read reg:%04x (%d), __func__, reg, priv-fe.dvb-num);
ret = i2c_transfer(priv-i2c, msg, 2);
if (ret == 2) {
ret = 0;
@@ -110,6 +171,9 @@ static int af9013_rd_regs_i2c(struct
