diff options
Diffstat (limited to 'drivers/media/dvb-frontends/a8293.c')
| -rw-r--r-- | drivers/media/dvb-frontends/a8293.c | 160 |
1 files changed, 154 insertions, 6 deletions
diff --git a/drivers/media/dvb-frontends/a8293.c b/drivers/media/dvb-frontends/a8293.c index ba38783b2b4f..cca7cbdd4c7c 100644 --- a/drivers/media/dvb-frontends/a8293.c +++ b/drivers/media/dvb-frontends/a8293.c @@ -7,20 +7,148 @@ #include "a8293.h" +#define A8293_FLAG_ODT 0x10 + struct a8293_dev { struct i2c_client *client; u8 reg[2]; + int volt_slew_nanos_per_mv; }; -static int a8293_set_voltage(struct dvb_frontend *fe, - enum fe_sec_voltage fe_sec_voltage) +/* + * When increasing voltage, do so in minimal steps over time, minimizing + * risk of vIN undervoltage. + */ + +static int a8293_set_voltage_slew(struct a8293_dev *dev, + struct i2c_client *client, + enum fe_sec_voltage fe_sec_voltage, + int min_nanos_per_mv) +{ + int ret; + u8 reg0, reg1; + int new_volt_idx; + const int idx_to_mv[] = { + 0, 12709, 13042, 13375, 14042, 15042, 18042, 18709, 19042 + }; + const u8 idx_to_reg[] = { + 0x00, 0x20, 0x21, 0x22, 0x24, 0x27, 0x28, 0x2A, 0x2B + }; + int this_volt_idx; + u8 status; + int prev_volt_idx; + + dev_dbg(&client->dev, "set_voltage_slew fe_sec_voltage=%d\n", + fe_sec_voltage); + + /* Read status register to clear any stale faults. */ + ret = i2c_master_recv(client, &status, 1); + if (ret < 0) + goto err; + + /* Determine previous voltage */ + switch (dev->reg[0] & 0x2F) { + case 0x00: + prev_volt_idx = 0; + break; + case 0x20: + prev_volt_idx = 1; + break; + case 0x21: + prev_volt_idx = 2; + break; + case 0x22: + prev_volt_idx = 3; + break; + case 0x24: + prev_volt_idx = 4; + break; + case 0x27: + prev_volt_idx = 5; + break; + case 0x28: + prev_volt_idx = 6; + break; + case 0x2A: + prev_volt_idx = 7; + break; + case 0x2B: + prev_volt_idx = 8; + break; + default: + prev_volt_idx = 0; + } + + /* Determine new voltage */ + switch (fe_sec_voltage) { + case SEC_VOLTAGE_OFF: + new_volt_idx = 0; + break; + case SEC_VOLTAGE_13: + new_volt_idx = 2; + break; + case SEC_VOLTAGE_18: + new_volt_idx = 6; + break; + default: + ret = -EINVAL; + goto err; + } + + /* Slew to new voltage if new voltage is greater than current voltage */ + this_volt_idx = prev_volt_idx; + if (this_volt_idx < new_volt_idx) { + while (this_volt_idx < new_volt_idx) { + int delta_mv = idx_to_mv[this_volt_idx+1] - idx_to_mv[this_volt_idx]; + int min_wait_time = delta_mv * min_nanos_per_mv; + + reg0 = idx_to_reg[this_volt_idx+1]; + reg0 |= A8293_FLAG_ODT; + + ret = i2c_master_send(client, ®0, 1); + if (ret < 0) + goto err; + dev->reg[0] = reg0; + this_volt_idx++; + usleep_range(min_wait_time, min_wait_time * 2); + } + } else { /* Else just set the voltage */ + reg0 = idx_to_reg[new_volt_idx]; + reg0 |= A8293_FLAG_ODT; + ret = i2c_master_send(client, ®0, 1); + if (ret < 0) + goto err; + dev->reg[0] = reg0; + } + + /* TMODE=0, TGATE=1 */ + reg1 = 0x82; + if (reg1 != dev->reg[1]) { + ret = i2c_master_send(client, ®1, 1); + if (ret < 0) + goto err; + dev->reg[1] = reg1; + } + + usleep_range(1500, 5000); + + return 0; +err: + dev_dbg(&client->dev, "failed=%d\n", ret); + return ret; +} + + +static int a8293_set_voltage_noslew(struct dvb_frontend *fe, + enum fe_sec_voltage fe_sec_voltage) { struct a8293_dev *dev = fe->sec_priv; struct i2c_client *client = dev->client; int ret; u8 reg0, reg1; - dev_dbg(&client->dev, "fe_sec_voltage=%d\n", fe_sec_voltage); + dev_dbg(&client->dev, "set_voltage_noslew fe_sec_voltage=%d\n", + fe_sec_voltage); switch (fe_sec_voltage) { case SEC_VOLTAGE_OFF: @@ -62,8 +190,27 @@ err: return ret; } -static int a8293_probe(struct i2c_client *client, - const struct i2c_device_id *id) +static int a8293_set_voltage(struct dvb_frontend *fe, + enum fe_sec_voltage fe_sec_voltage) +{ + struct a8293_dev *dev = fe->sec_priv; + struct i2c_client *client = dev->client; + int volt_slew_nanos_per_mv = dev->volt_slew_nanos_per_mv; + + dev_dbg(&client->dev, "set_voltage volt_slew_nanos_per_mv=%d\n", + volt_slew_nanos_per_mv); + + /* Use slew version if slew rate is set to a sane value */ + if (volt_slew_nanos_per_mv > 0 && volt_slew_nanos_per_mv < 1600) + a8293_set_voltage_slew(dev, client, fe_sec_voltage, + volt_slew_nanos_per_mv); + else + a8293_set_voltage_noslew(fe, fe_sec_voltage); + + return 0; +} + +static int a8293_probe(struct i2c_client *client) { struct a8293_dev *dev; struct a8293_platform_data *pdata = client->dev.platform_data; @@ -78,6 +225,7 @@ static int a8293_probe(struct i2c_client *client, } dev->client = client; + dev->volt_slew_nanos_per_mv = pdata->volt_slew_nanos_per_mv; /* check if the SEC is there */ ret = i2c_master_recv(client, buf, 2); @@ -118,7 +266,7 @@ static struct i2c_driver a8293_driver = { .name = "a8293", .suppress_bind_attrs = true, }, - .probe = a8293_probe, + .probe_new = a8293_probe, .remove = a8293_remove, .id_table = a8293_id_table, }; |