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path: root/drivers/nfc/trf7970a.c
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Diffstat (limited to 'drivers/nfc/trf7970a.c')
-rw-r--r--drivers/nfc/trf7970a.c139
1 files changed, 105 insertions, 34 deletions
diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 29ca9c328df2..d17c701c7888 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -272,12 +272,18 @@
#define TRF7970A_MODULATOR_EN_OOK BIT(6)
#define TRF7970A_MODULATOR_27MHZ BIT(7)
+#define TRF7970A_RX_GAIN_REDUCTION_MAX_DB 15
+#define TRF7970A_RX_GAIN_REDUCTION_DB_PER_LSB 5
#define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM BIT(0)
#define TRF7970A_RX_SPECIAL_SETTINGS_AGCR BIT(1)
-#define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB (0x0 << 2)
-#define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB (0x1 << 2)
-#define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB (0x2 << 2)
-#define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB (0x3 << 2)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT 2
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_MAX (0x3)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_MASK (TRF7970A_RX_SPECIAL_SETTINGS_GD_MAX << \
+ TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB (0x0 << TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB (0x1 << TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB (0x2 << TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB (0x3 << TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT)
#define TRF7970A_RX_SPECIAL_SETTINGS_HBT BIT(4)
#define TRF7970A_RX_SPECIAL_SETTINGS_M848 BIT(5)
#define TRF7970A_RX_SPECIAL_SETTINGS_C424 BIT(6)
@@ -424,7 +430,8 @@ struct trf7970a {
enum trf7970a_state state;
struct device *dev;
struct spi_device *spi;
- struct regulator *regulator;
+ struct regulator *vin_regulator;
+ struct regulator *vddio_regulator;
struct nfc_digital_dev *ddev;
u32 quirks;
bool is_initiator;
@@ -451,6 +458,8 @@ struct trf7970a {
unsigned int timeout;
bool ignore_timeout;
struct delayed_work timeout_work;
+ u8 rx_gain_reduction;
+ bool custom_rx_gain_reduction;
};
static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
@@ -550,6 +559,41 @@ static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
return ret;
}
+static int trf7970a_update_rx_gain_reduction(struct trf7970a *trf)
+{
+ int ret = 0;
+ u8 reg;
+
+ if (!trf->custom_rx_gain_reduction)
+ return 0;
+
+ ret = trf7970a_read(trf, TRF7970A_RX_SPECIAL_SETTINGS, &reg);
+ if (ret)
+ return ret;
+ reg &= ~(TRF7970A_RX_SPECIAL_SETTINGS_GD_MASK);
+ reg |= trf->rx_gain_reduction;
+
+ ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS, reg);
+
+ return ret;
+}
+
+static int trf7970a_update_iso_ctrl_register(struct trf7970a *trf, u8 iso_ctrl)
+{
+ int ret;
+
+ ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
+ if (ret)
+ return ret;
+ /*
+ * Every time the ISO_CTRL register is written, the RX special setting register is reset by
+ * the chip. When a custom gain reguduction is required, it should be rewritten now.
+ */
+ ret = trf7970a_update_rx_gain_reduction(trf);
+
+ return ret;
+}
+
static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
{
int ret;
@@ -929,8 +973,7 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
}
if (iso_ctrl != trf->iso_ctrl) {
- ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
- iso_ctrl);
+ ret = trf7970a_update_iso_ctrl_register(trf, iso_ctrl);
if (ret)
goto err_unlock_exit;
@@ -1034,6 +1077,11 @@ static int trf7970a_init(struct trf7970a *trf)
if (ret)
goto err_out;
+ /* Set the gain reduction after soft init */
+ ret = trf7970a_update_rx_gain_reduction(trf);
+ if (ret)
+ goto err_out;
+
ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
if (ret)
goto err_out;
@@ -1308,7 +1356,7 @@ static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
}
if (iso_ctrl != trf->iso_ctrl) {
- ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
+ ret = trf7970a_update_iso_ctrl_register(trf, iso_ctrl);
if (ret)
return ret;
@@ -1440,7 +1488,7 @@ static int trf7970a_per_cmd_config(struct trf7970a *trf,
}
if (iso_ctrl != trf->iso_ctrl) {
- ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
+ ret = trf7970a_update_iso_ctrl_register(trf, iso_ctrl);
if (ret)
return ret;
@@ -1604,8 +1652,7 @@ static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
*/
if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
(trf->iso_ctrl_tech != trf->iso_ctrl)) {
- ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
- trf->iso_ctrl_tech);
+ ret = trf7970a_update_iso_ctrl_register(trf, trf->iso_ctrl_tech);
trf->iso_ctrl = trf->iso_ctrl_tech;
}
@@ -1653,7 +1700,7 @@ static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
trf->framing = framing;
if (iso_ctrl != trf->iso_ctrl) {
- ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
+ ret = trf7970a_update_iso_ctrl_register(trf, iso_ctrl);
if (ret)
return ret;
@@ -1754,6 +1801,10 @@ static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
if (ret)
goto out_err;
+ ret = trf7970a_update_rx_gain_reduction(trf);
+ if (ret)
+ goto out_err;
+
ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
if (ret)
@@ -1883,7 +1934,7 @@ static int trf7970a_power_up(struct trf7970a *trf)
if (trf->state != TRF7970A_ST_PWR_OFF)
return 0;
- ret = regulator_enable(trf->regulator);
+ ret = regulator_enable(trf->vin_regulator);
if (ret) {
dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
return ret;
@@ -1926,7 +1977,7 @@ static int trf7970a_power_down(struct trf7970a *trf)
if (trf->en2_gpiod && !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW))
gpiod_set_value_cansleep(trf->en2_gpiod, 0);
- ret = regulator_disable(trf->regulator);
+ ret = regulator_disable(trf->vin_regulator);
if (ret)
dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
ret);
@@ -1944,6 +1995,10 @@ static int trf7970a_startup(struct trf7970a *trf)
if (ret)
return ret;
+ ret = trf7970a_update_rx_gain_reduction(trf);
+ if (ret)
+ return ret;
+
pm_runtime_set_active(trf->dev);
pm_runtime_enable(trf->dev);
pm_runtime_mark_last_busy(trf->dev);
@@ -1992,6 +2047,7 @@ static int trf7970a_probe(struct spi_device *spi)
struct trf7970a *trf;
int uvolts, autosuspend_delay, ret;
u32 clk_freq = TRF7970A_13MHZ_CLOCK_FREQUENCY;
+ u32 rx_gain_reduction_db;
if (!np) {
dev_err(&spi->dev, "No Device Tree entry\n");
@@ -2053,6 +2109,20 @@ static int trf7970a_probe(struct spi_device *spi)
trf->modulator_sys_clk_ctrl = 0;
}
+ if (of_property_read_u32(np, "ti,rx-gain-reduction-db", &rx_gain_reduction_db) == 0) {
+ if (rx_gain_reduction_db > TRF7970A_RX_GAIN_REDUCTION_MAX_DB) {
+ dev_warn(trf->dev, "RX Gain reduction too high. Ignored\n");
+ } else if ((rx_gain_reduction_db % TRF7970A_RX_GAIN_REDUCTION_DB_PER_LSB)) {
+ dev_warn(trf->dev, "RX Gain must be set in 5 dB increments. Ignored\n");
+ } else {
+ dev_dbg(trf->dev, "RX gain set to -%udB\n", rx_gain_reduction_db);
+ trf->rx_gain_reduction = ((rx_gain_reduction_db /
+ TRF7970A_RX_GAIN_REDUCTION_DB_PER_LSB) <<
+ TRF7970A_RX_SPECIAL_SETTINGS_GD_SHIFT);
+ trf->custom_rx_gain_reduction = true;
+ }
+ }
+
ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
trf7970a_irq,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
@@ -2065,37 +2135,37 @@ static int trf7970a_probe(struct spi_device *spi)
mutex_init(&trf->lock);
INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
- trf->regulator = devm_regulator_get(&spi->dev, "vin");
- if (IS_ERR(trf->regulator)) {
- ret = PTR_ERR(trf->regulator);
+ trf->vin_regulator = devm_regulator_get(&spi->dev, "vin");
+ if (IS_ERR(trf->vin_regulator)) {
+ ret = PTR_ERR(trf->vin_regulator);
dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
goto err_destroy_lock;
}
- ret = regulator_enable(trf->regulator);
+ ret = regulator_enable(trf->vin_regulator);
if (ret) {
dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
goto err_destroy_lock;
}
- uvolts = regulator_get_voltage(trf->regulator);
+ uvolts = regulator_get_voltage(trf->vin_regulator);
if (uvolts > 4000000)
trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
- trf->regulator = devm_regulator_get(&spi->dev, "vdd-io");
- if (IS_ERR(trf->regulator)) {
- ret = PTR_ERR(trf->regulator);
+ trf->vddio_regulator = devm_regulator_get(&spi->dev, "vdd-io");
+ if (IS_ERR(trf->vddio_regulator)) {
+ ret = PTR_ERR(trf->vddio_regulator);
dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
- goto err_destroy_lock;
+ goto err_disable_vin_regulator;
}
- ret = regulator_enable(trf->regulator);
+ ret = regulator_enable(trf->vddio_regulator);
if (ret) {
dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
- goto err_destroy_lock;
+ goto err_disable_vin_regulator;
}
- if (regulator_get_voltage(trf->regulator) == 1800000) {
+ if (regulator_get_voltage(trf->vddio_regulator) == 1800000) {
trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
}
@@ -2108,7 +2178,7 @@ static int trf7970a_probe(struct spi_device *spi)
if (!trf->ddev) {
dev_err(trf->dev, "Can't allocate NFC digital device\n");
ret = -ENOMEM;
- goto err_disable_regulator;
+ goto err_disable_vddio_regulator;
}
nfc_digital_set_parent_dev(trf->ddev, trf->dev);
@@ -2137,14 +2207,16 @@ err_shutdown:
trf7970a_shutdown(trf);
err_free_ddev:
nfc_digital_free_device(trf->ddev);
-err_disable_regulator:
- regulator_disable(trf->regulator);
+err_disable_vddio_regulator:
+ regulator_disable(trf->vddio_regulator);
+err_disable_vin_regulator:
+ regulator_disable(trf->vin_regulator);
err_destroy_lock:
mutex_destroy(&trf->lock);
return ret;
}
-static int trf7970a_remove(struct spi_device *spi)
+static void trf7970a_remove(struct spi_device *spi)
{
struct trf7970a *trf = spi_get_drvdata(spi);
@@ -2157,11 +2229,10 @@ static int trf7970a_remove(struct spi_device *spi)
nfc_digital_unregister_device(trf->ddev);
nfc_digital_free_device(trf->ddev);
- regulator_disable(trf->regulator);
+ regulator_disable(trf->vddio_regulator);
+ regulator_disable(trf->vin_regulator);
mutex_destroy(&trf->lock);
-
- return 0;
}
#ifdef CONFIG_PM_SLEEP
@@ -2231,7 +2302,7 @@ static const struct dev_pm_ops trf7970a_pm_ops = {
trf7970a_pm_runtime_resume, NULL)
};
-static const struct of_device_id trf7970a_of_match[] = {
+static const struct of_device_id trf7970a_of_match[] __maybe_unused = {
{.compatible = "ti,trf7970a",},
{},
};
generated by cgit (git 2.34.1) at 2025-12-25 20:06:28 +0000