Added a device tree option xceiver_standby, which if present will cause GPIO to be placed in GPIO mode, with automatic transceiver control enabled.
Added a flag to the summary message printed following successful initialisation, to help debug it being enabled.
Have checked with a logic analyser that GPIO0 transitions from high to low as expected when the interface is brought up, and low to high when taken down.
I've renamed mcp251xfd_chip_rx_int_disable to mcp251xfd_chip_configure_gpio trying to reflect its new role, considering that it doesn't just manage the rx interrupt anymore. Perhaps separate functions updating the bits independently might be better?
Signed-off-by: Phil Greenland <phil@xxxxxxxxxxxxxxx>
---
.../net/can/spi/mcp251xfd/mcp251xfd-core.c | 56 ++++++++++---------
drivers/net/can/spi/mcp251xfd/mcp251xfd.h | 2 +
2 files changed, 31 insertions(+), 27 deletions(-)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
index e16dc482f..9ee2c69c5 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
@@ -801,40 +801,37 @@ static int mcp251xfd_set_bittiming(const struct mcp251xfd_priv *priv)
return regmap_write(priv->map_reg, MCP251XFD_REG_TDC, val);
}
-static int mcp251xfd_chip_rx_int_enable(const struct mcp251xfd_priv *priv)
+static int mcp251xfd_chip_configure_gpio(const struct mcp251xfd_priv *priv,
+ bool rx_int_enable)
{
- u32 val;
-
- if (!priv->rx_int)
- return 0;
+ u32 val = 0;
/* Configure GPIOs:
- * - PIN0: GPIO Input
- * - PIN1: GPIO Input/RX Interrupt
+ * - PIN0: GPIO Input/Transceiver standby (if enabled)
+ * - PIN1: GPIO Input/RX Interrupt (if enabled)
*
* PIN1 must be Input, otherwise there is a glitch on the
* rx-INT line. It happens between setting the PIN as output
* (in the first byte of the SPI transfer) and configuring the
* PIN as interrupt (in the last byte of the SPI transfer).
*/
- val = MCP251XFD_REG_IOCON_PM0 | MCP251XFD_REG_IOCON_TRIS1 |
- MCP251XFD_REG_IOCON_TRIS0;
- return regmap_write(priv->map_reg, MCP251XFD_REG_IOCON, val);
-}
+ if (priv->xceiver_standby) {
+ /* Transceiver control enabled, place in GPIO mode with auto transceiver standby */
+ val |= MCP251XFD_REG_IOCON_PM0 | MCP251XFD_REG_IOCON_XSTBYEN;
+ } else {
+ /* Transceiver control disabled, place in GPIO mode and tristate */
+ val |= MCP251XFD_REG_IOCON_PM0 | MCP251XFD_REG_IOCON_TRIS0;
+ }
-static int mcp251xfd_chip_rx_int_disable(const struct mcp251xfd_priv *priv)
-{
- u32 val;
+ if (priv->rx_int && rx_int_enable) {
+ /* INT1 enabled, tristate GPIO1 (overridden by INT enable) */
+ val |= MCP251XFD_REG_IOCON_TRIS1;
- if (!priv->rx_int)
- return 0;
+ } else {
+ /* INT1 disabled, place in GPIO mode and tristate */
+ val |= MCP251XFD_REG_IOCON_PM1 | MCP251XFD_REG_IOCON_TRIS1;
+ }
- /* Configure GPIOs:
- * - PIN0: GPIO Input
- * - PIN1: GPIO Input
- */
- val = MCP251XFD_REG_IOCON_PM1 | MCP251XFD_REG_IOCON_PM0 |
- MCP251XFD_REG_IOCON_TRIS1 | MCP251XFD_REG_IOCON_TRIS0;
return regmap_write(priv->map_reg, MCP251XFD_REG_IOCON, val);
}
@@ -1070,7 +1067,7 @@ static int mcp251xfd_chip_stop(struct mcp251xfd_priv *priv,
priv->can.state = state;
mcp251xfd_chip_interrupts_disable(priv);
- mcp251xfd_chip_rx_int_disable(priv);
+ mcp251xfd_chip_configure_gpio(priv, false);
return mcp251xfd_chip_set_mode(priv, MCP251XFD_REG_CON_MODE_SLEEP);
}
@@ -1090,7 +1087,8 @@ static int mcp251xfd_chip_start(struct mcp251xfd_priv *priv)
if (err)
goto out_chip_stop;
- err = mcp251xfd_chip_rx_int_enable(priv);
+ /* enable rx interrupt */
+ err = mcp251xfd_chip_configure_gpio(priv, true);
if (err)
goto out_chip_stop;
@@ -2645,7 +2643,8 @@ static int mcp251xfd_register_check_rx_int(struct mcp251xfd_priv *priv)
if (!priv->rx_int)
return 0;
- err = mcp251xfd_chip_rx_int_enable(priv);
+ /* enable rx interrupt */
+ err = mcp251xfd_chip_configure_gpio(priv, true);
if (err)
return err;
@@ -2654,7 +2653,8 @@ static int mcp251xfd_register_check_rx_int(struct mcp251xfd_priv *priv)
*/
rx_pending = gpiod_get_value_cansleep(priv->rx_int);
- err = mcp251xfd_chip_rx_int_disable(priv);
+ /* disable rx interrupt */
+ err = mcp251xfd_chip_configure_gpio(priv, false);
if (err)
return err;
@@ -2724,11 +2724,12 @@ mcp251xfd_register_done(const struct mcp251xfd_priv *priv)
return err;
netdev_info(priv->ndev,
- "%s rev%lu.%lu (%cRX_INT %cMAB_NO_WARN %cCRC_REG %cCRC_RX %cCRC_TX %cECC %cHD c:%u.%02uMHz m:%u.%02uMHz r:%u.%02uMHz e:%u.%02uMHz) successfully initialized.\n",
+ "%s rev%lu.%lu (%cRX_INT %cXCVR_STBY %cMAB_NO_WARN %cCRC_REG %cCRC_RX %cCRC_TX %cECC %cHD c:%u.%02uMHz m:%u.%02uMHz r:%u.%02uMHz e:%u.%02uMHz) successfully initialized.\n",
mcp251xfd_get_model_str(priv),
FIELD_GET(MCP251XFD_REG_DEVID_ID_MASK, dev_id),
FIELD_GET(MCP251XFD_REG_DEVID_REV_MASK, dev_id),
priv->rx_int ? '+' : '-',
+ priv->xceiver_standby ? '+' : '-',
MCP251XFD_QUIRK_ACTIVE(MAB_NO_WARN),
MCP251XFD_QUIRK_ACTIVE(CRC_REG),
MCP251XFD_QUIRK_ACTIVE(CRC_RX),
@@ -2948,6 +2949,7 @@ static int mcp251xfd_probe(struct spi_device *spi)
priv->clk = clk;
priv->reg_vdd = reg_vdd;
priv->reg_xceiver = reg_xceiver;
+ priv->xceiver_standby = device_property_read_bool(&spi->dev, "xceiver_standby");
match = device_get_match_data(&spi->dev);
if (match)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd.h b/drivers/net/can/spi/mcp251xfd/mcp251xfd.h
index 0f322daba..ad658faa2 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd.h
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd.h
@@ -612,6 +612,8 @@ struct mcp251xfd_priv {
struct mcp251xfd_devtype_data devtype_data;
struct can_berr_counter bec;
+
+ bool xceiver_standby;
};
#define MCP251XFD_IS(_model) \
--
2.25.1
