[PATCH 5.15 451/731] extcon: usbc-tusb320: Add support for mode setting and reset

Greg Kroah-Hartman
2022-12-28T15:26:31Z

From: Yassine Oudjana <y.oudjana@protonmail.com>

[ Upstream commit 70c55d6be634e5f9894169340f3fe5c73f53ac2d ]

Reset the chip and set its mode to default (maintain mode set by PORT pin)
during probe to make sure it comes up in the default state.

Signed-off-by: Yassine Oudjana <y.oudjana@protonmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Stable-dep-of: 581c848b610d ("extcon: usbc-tusb320: Update state on probe even if no IRQ pending")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/extcon/extcon-usbc-tusb320.c | 85 ++++++++++++++++++++++++++--
1 file changed, 81 insertions(+), 4 deletions(-)

diff --git a/drivers/extcon/extcon-usbc-tusb320.c b/drivers/extcon/extcon-usbc-tusb320.c
index 805af73b4152..1ed1dfe54206 100644
--- a/drivers/extcon/extcon-usbc-tusb320.c
+++ b/drivers/extcon/extcon-usbc-tusb320.c
@@ -19,15 +19,32 @@
#define TUSB320_REG9_ATTACHED_STATE_MASK 0x3
#define TUSB320_REG9_CABLE_DIRECTION BIT(5)
#define TUSB320_REG9_INTERRUPT_STATUS BIT(4)
-#define TUSB320_ATTACHED_STATE_NONE 0x0
-#define TUSB320_ATTACHED_STATE_DFP 0x1
-#define TUSB320_ATTACHED_STATE_UFP 0x2
-#define TUSB320_ATTACHED_STATE_ACC 0x3
+
+#define TUSB320_REGA 0xa
+#define TUSB320_REGA_I2C_SOFT_RESET BIT(3)
+#define TUSB320_REGA_MODE_SELECT_SHIFT 4
+#define TUSB320_REGA_MODE_SELECT_MASK 0x3
+
+enum tusb320_attached_state {
+ TUSB320_ATTACHED_STATE_NONE,
+ TUSB320_ATTACHED_STATE_DFP,
+ TUSB320_ATTACHED_STATE_UFP,
+ TUSB320_ATTACHED_STATE_ACC,
+};
+
+enum tusb320_mode {
+ TUSB320_MODE_PORT,
+ TUSB320_MODE_UFP,
+ TUSB320_MODE_DFP,
+ TUSB320_MODE_DRP,
+};

struct tusb320_priv {
struct device *dev;
struct regmap *regmap;
struct extcon_dev *edev;
+
+ enum tusb320_attached_state state;
};

static const char * const tusb_attached_states[] = {
@@ -62,6 +79,53 @@ static int tusb320_check_signature(struct tusb320_priv *priv)
return 0;
}

+static int tusb320_set_mode(struct tusb320_priv *priv, enum tusb320_mode mode)
+{
+ int ret;
+
+ /* Mode cannot be changed while cable is attached */
+ if (priv->state != TUSB320_ATTACHED_STATE_NONE)
+ return -EBUSY;
+
+ /* Write mode */
+ ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
+ TUSB320_REGA_MODE_SELECT_MASK << TUSB320_REGA_MODE_SELECT_SHIFT,
+ mode << TUSB320_REGA_MODE_SELECT_SHIFT);
+ if (ret) {
+ dev_err(priv->dev, "failed to write mode: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int tusb320_reset(struct tusb320_priv *priv)
+{
+ int ret;
+
+ /* Set mode to default (follow PORT pin) */
+ ret = tusb320_set_mode(priv, TUSB320_MODE_PORT);
+ if (ret && ret != -EBUSY) {
+ dev_err(priv->dev,
+ "failed to set mode to PORT: %d\n", ret);
+ return ret;
+ }
+
+ /* Perform soft reset */
+ ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
+ TUSB320_REGA_I2C_SOFT_RESET, 1);
+ if (ret) {
+ dev_err(priv->dev,
+ "failed to write soft reset bit: %d\n", ret);
+ return ret;
+ }
+
+ /* Wait for chip to go through reset */
+ msleep(95);
+
+ return 0;
+}
+
static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
{
struct tusb320_priv *priv = dev_id;
@@ -96,6 +160,8 @@ static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
extcon_sync(priv->edev, EXTCON_USB);
extcon_sync(priv->edev, EXTCON_USB_HOST);

+ priv->state = state;
+
regmap_write(priv->regmap, TUSB320_REG9, reg);

return IRQ_HANDLED;
@@ -145,6 +211,17 @@ static int tusb320_extcon_probe(struct i2c_client *client,
/* update initial state */
tusb320_irq_handler(client->irq, priv);

+ /* Reset chip to its default state */
+ ret = tusb320_reset(priv);
+ if (ret)
+ dev_warn(priv->dev, "failed to reset chip: %d\n", ret);
+ else
+ /*
+ * State and polarity might change after a reset, so update
+ * them again and make sure the interrupt status bit is cleared.
+ */
+ tusb320_irq_handler(client->irq, priv);
+
ret = devm_request_threaded_irq(priv->dev, client->irq, NULL,
tusb320_irq_handler,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
--
2.35.1