[PATCH net-next 12/12] net: pse-pd: tps23881: Add support for PSE events and interrupts

Kory Maincent
2024-10-02T16:29:15Z

From: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>

Add support for PSE event reporting through interrupts. Set up the newly
introduced devm_pse_irq_helper helper to register the interrupt. Events are
reported for over-current and over-temperature conditions.

This patch also adds support for an OSS GPIO line to turn off all low
priority ports in case of an over-current event.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
---
drivers/net/pse-pd/tps23881.c | 123 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 122 insertions(+), 1 deletion(-)

diff --git a/drivers/net/pse-pd/tps23881.c b/drivers/net/pse-pd/tps23881.c
index ddb44a17218a..03f36b641bb4 100644
--- a/drivers/net/pse-pd/tps23881.c
+++ b/drivers/net/pse-pd/tps23881.c
@@ -17,6 +17,13 @@

#define TPS23881_MAX_CHANS 8

+#define TPS23881_REG_IT 0x0
+#define TPS23881_REG_IT_MASK 0x1
+#define TPS23881_REG_IT_IFAULT BIT(5)
+#define TPS23881_REG_IT_SUPF BIT(7)
+#define TPS23881_REG_FAULT 0x7
+#define TPS23881_REG_SUPF_EVENT 0xb
+#define TPS23881_REG_TSD BIT(7)
#define TPS23881_REG_PW_STATUS 0x10
#define TPS23881_REG_OP_MODE 0x12
#define TPS23881_OP_MODE_SEMIAUTO 0xaaaa
@@ -25,6 +32,7 @@
#define TPS23881_REG_PW_PRIO 0x15
#define TPS23881_REG_GEN_MASK 0x17
#define TPS23881_REG_NBITACC BIT(5)
+#define TPS23881_REG_INTEN BIT(7)
#define TPS23881_REG_PW_EN 0x19
#define TPS23881_REG_2PAIR_POL1 0x1e
#define TPS23881_REG_PORT_MAP 0x26
@@ -59,6 +67,7 @@ struct tps23881_priv {
struct pse_controller_dev pcdev;
struct device_node *np;
struct tps23881_port_desc port[TPS23881_MAX_CHANS];
+ struct gpio_desc *oss;
};

static struct tps23881_priv *to_tps23881_priv(struct pse_controller_dev *pcdev)
@@ -1088,11 +1097,112 @@ static int tps23881_flash_sram_fw(struct i2c_client *client)
return 0;
}

+static void tps23881_turn_off_low_prio(struct tps23881_priv *priv)
+{
+ dev_info(&priv->client->dev,
+ "turn off low priority ports due to over current event.\n");
+ gpiod_set_value_cansleep(priv->oss, 1);
+
+ /* TPS23880 datasheet (Rev G) indicates minimum OSS pulse is 5us */
+ usleep_range(5, 10);
+ gpiod_set_value_cansleep(priv->oss, 0);
+}
+
+static int tps23881_irq_handler(int irq, struct pse_irq_data *pid,
+ unsigned long *dev_mask)
+{
+ struct tps23881_priv *priv = (struct tps23881_priv *)pid->data;
+ struct i2c_client *client = priv->client;
+ struct pse_err_state *stat;
+ int ret, i;
+ u16 val;
+
+ *dev_mask = 0;
+ for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+ stat = &pid->states[i];
+ stat->notifs = 0;
+ stat->errors = 0;
+ }
+
+ ret = i2c_smbus_read_word_data(client, TPS23881_REG_IT);
+ if (ret < 0)
+ return PSE_FAILED_RETRY;
+
+ val = (u16)ret;
+ if (val & TPS23881_REG_IT_SUPF) {
+ ret = i2c_smbus_read_word_data(client, TPS23881_REG_SUPF_EVENT);
+ if (ret < 0)
+ return PSE_FAILED_RETRY;
+
+ if (ret & TPS23881_REG_TSD) {
+ for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+ stat = &pid->states[i];
+ *dev_mask |= 1 << i;
+ stat->notifs = PSE_EVENT_OVER_TEMP;
+ stat->errors = PSE_ERROR_OVER_TEMP;
+ }
+ }
+ }
+
+ if (val & (TPS23881_REG_IT_IFAULT | TPS23881_REG_IT_IFAULT << 8)) {
+ ret = i2c_smbus_read_word_data(client, TPS23881_REG_FAULT);
+ if (ret < 0)
+ return PSE_FAILED_RETRY;
+
+ val = (u16)(ret & 0xf0f);
+
+ /* Power cut detected, shutdown low priority port */
+ if (val && priv->oss)
+ tps23881_turn_off_low_prio(priv);
+
+ *dev_mask |= val;
+ for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+ if (val & BIT(i)) {
+ stat = &pid->states[i];
+ stat->notifs = PSE_EVENT_OVER_CURRENT;
+ stat->errors = PSE_ERROR_OVER_CURRENT;
+ }
+ }
+ }
+
+ return PSE_ERROR_CLEARED;
+}
+
+static int tps23881_setup_irq(struct tps23881_priv *priv, int irq)
+{
+ int errs = PSE_ERROR_OVER_CURRENT | PSE_ERROR_OVER_TEMP;
+ struct i2c_client *client = priv->client;
+ struct pse_irq_desc irq_desc = {
+ .name = "tps23881-irq",
+ .map_event = tps23881_irq_handler,
+ .data = priv,
+ };
+ int ret;
+ u16 val;
+
+ val = TPS23881_REG_IT_IFAULT | TPS23881_REG_IT_SUPF |
+ TPS23881_REG_IT_IFAULT << 8 | TPS23881_REG_IT_SUPF << 8;
+ ret = i2c_smbus_write_word_data(client, TPS23881_REG_IT_MASK, val);
+ if (ret)
+ return ret;
+
+ ret = i2c_smbus_read_word_data(client, TPS23881_REG_GEN_MASK);
+ if (ret < 0)
+ return ret;
+
+ val = (u16)(ret | TPS23881_REG_INTEN | TPS23881_REG_INTEN << 8);
+ ret = i2c_smbus_write_word_data(client, TPS23881_REG_GEN_MASK, val);
+ if (ret < 0)
+ return ret;
+
+ return devm_pse_irq_helper(&priv->pcdev, irq, 0, errs, &irq_desc);
+}
+
static int tps23881_i2c_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct tps23881_priv *priv;
- struct gpio_desc *reset;
+ struct gpio_desc *reset, *oss;
int ret;
u8 val;

@@ -1169,6 +1279,17 @@ static int tps23881_i2c_probe(struct i2c_client *client)
"failed to register PSE controller\n");
}

+ oss = devm_gpiod_get_optional(dev, "oss", GPIOD_OUT_LOW);
+ if (IS_ERR(oss))
+ return dev_err_probe(&client->dev, PTR_ERR(oss), "Failed to get OSS GPIO\n");
+ priv->oss = oss;
+
+ if (client->irq) {
+ ret = tps23881_setup_irq(priv, client->irq);
+ if (ret)
+ return ret;
+ }
+
return ret;
}

--
2.34.1