From 63a761eef55759c0bc725739fe575193c09fa4ef Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 20 Apr 2017 12:04:33 +0200 Subject: [PATCH] i2c: rcar: clarify PM handling with more comments PM handling is correct but might be a bit subtle. Add some comments for clarification. Signed-off-by: Wolfram Sang Acked-by: Kuninori Morimoto Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-rcar.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 66b84bf51bbf..214bf2835d1f 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -753,6 +753,7 @@ static int rcar_reg_slave(struct i2c_client *slave) if (slave->flags & I2C_CLIENT_TEN) return -EAFNOSUPPORT; + /* Keep device active for slave address detection logic */ pm_runtime_get_sync(rcar_i2c_priv_to_dev(priv)); priv->slave = slave; @@ -856,13 +857,14 @@ static int rcar_i2c_probe(struct platform_device *pdev) priv->dma_direction = DMA_NONE; priv->dma_rx = priv->dma_tx = ERR_PTR(-EPROBE_DEFER); + /* Activate device for clock calculation */ pm_runtime_enable(dev); pm_runtime_get_sync(dev); ret = rcar_i2c_clock_calculate(priv, &i2c_t); if (ret < 0) goto out_pm_put; - /* Don't suspend when multi-master to keep arbitration working */ + /* Stay always active when multi-master to keep arbitration working */ if (of_property_read_bool(dev->of_node, "multi-master")) priv->flags |= ID_P_PM_BLOCKED; else