#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:
return ret;
}
+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;
}
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);