[PATCH net-next 01/11] can: tcan4x5x: put tcan into sleep when removing driver
flat view
COLD59d
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2026-08-17 23:34:28
Also in:
linux-can
Subsystem:
can network drivers, mcan device driver, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Markus Schneider-Pargmann, Linus Torvalds
From: Sean Nyekjaer <redacted> Put the tcan4x5x transceiver into sleep mode when the driver is removed, instead of leaving it in its current operating mode. This reduces power consumption(3mA@12V) once the driver is no longer bound to the device. Signed-off-by: Sean Nyekjaer <redacted> Link: https://patch.msgid.link/20260805110708.3220251-1-sean@geanix.com (local) [mkl: tcan4x5x_power_enable(): reduce scope of ret] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/can/m_can/tcan4x5x-core.c | 31 +++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c
index 31cc9d0abd45..a5b8829aa519 100644
--- a/drivers/net/can/m_can/tcan4x5x-core.c
+++ b/drivers/net/can/m_can/tcan4x5x-core.c@@ -211,8 +211,31 @@ static int tcan4x5x_write_fifo(struct m_can_classdev *cdev, return regmap_bulk_write(priv->regmap, TCAN4X5X_MRAM_START + addr_offset, val, val_count); } -static int tcan4x5x_power_enable(struct regulator *reg, int enable) +static int tcan4x5x_power_enable(struct tcan4x5x_priv *priv, int enable) { + struct regulator *reg = priv->power; + + /* + * Put the device into sleep mode if the RST pin is available, + * since a wake-up event, RST pin toggle, or power cycle are the only + * ways to exit sleep mode. + * Redundant if the regulator is exclusive to this device, but that + * can't be determined here. + * + * Datasheet: TCAN4550, section "8.4.3 Sleep Mode" + * https://www.ti.com/lit/gpn/tcan4550 + */ + if (priv->reset_gpio && !enable) { + int ret; + + ret = regmap_update_bits(priv->regmap, TCAN4X5X_CONFIG, + TCAN4X5X_MODE_SEL_MASK, + TCAN4X5X_MODE_SLEEP); + if (ret) + dev_err(&priv->spi->dev, "Setting sleep mode failed %pe\n", + ERR_PTR(ret)); + } + if (IS_ERR_OR_NULL(reg)) return 0;
@@ -476,7 +499,7 @@ static int tcan4x5x_can_probe(struct spi_device *spi) goto out_m_can_class_free_dev; } - ret = tcan4x5x_power_enable(priv->power, 1); + ret = tcan4x5x_power_enable(priv, 1); if (ret) { dev_err(&spi->dev, "Enabling regulator failed %pe\n", ERR_PTR(ret));
@@ -531,7 +554,7 @@ static int tcan4x5x_can_probe(struct spi_device *spi) return 0; out_power: - tcan4x5x_power_enable(priv->power, 0); + tcan4x5x_power_enable(priv, 0); out_m_can_class_free_dev: m_can_class_free_dev(mcan_class->net); return ret;
@@ -543,7 +566,7 @@ static void tcan4x5x_can_remove(struct spi_device *spi) m_can_class_unregister(&priv->cdev); - tcan4x5x_power_enable(priv->power, 0); + tcan4x5x_power_enable(priv, 0); m_can_class_free_dev(priv->cdev.net); }
base-commit: e6a5d573d24cd375e09d24f136523cb3cc85c9d3 -- 2.53.0