From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Date: Wed, 16 Dec 2015 18:44:20 +0000 Subject: [RFC 3/3] i2c: rcar: disable PM in multi-master mode Message-Id: <1450291460-10514-4-git-send-email-wsa@the-dreams.de> List-Id: References: <1450291460-10514-1-git-send-email-wsa@the-dreams.de> In-Reply-To: <1450291460-10514-1-git-send-email-wsa@the-dreams.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-i2c@vger.kernel.org Cc: linux-sh@vger.kernel.org, Magnus Damm , Simon Horman , Laurent Pinchart , Geert Uytterhoeven , Wolfram Sang , linux-pm@vger.kernel.org From: Wolfram Sang In multi master mode, the IP core needs to be always active for arbitration reasons. Get the config from DT and set up PM depending on the config. Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-rcar.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 79fd2aab8fa087..7c523dcaee3e48 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -96,6 +96,9 @@ #define ID_DONE (1 << 2) #define ID_ARBLOST (1 << 3) #define ID_NACK (1 << 4) +/* persistent flags */ +#define ID_P_PM_BLOCKED (1 << 31) +#define ID_P_MASK ID_P_PM_BLOCKED enum rcar_i2c_type { I2C_RCAR_GEN1, @@ -277,7 +280,7 @@ static void rcar_i2c_next_msg(struct rcar_i2c_priv *priv) { priv->msg++; priv->msgs_left--; - priv->flags = 0; + priv->flags &= ID_P_MASK; rcar_i2c_prepare_msg(priv); } @@ -495,7 +498,7 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap, /* init first message */ priv->msg = msgs; priv->msgs_left = num; - priv->flags = ID_FIRST_MSG; + priv->flags = (priv->flags & ID_P_MASK) | ID_FIRST_MSG; rcar_i2c_prepare_msg(priv); time_left = wait_event_timeout(priv->wait, priv->flags & ID_DONE, @@ -630,7 +633,13 @@ static int rcar_i2c_probe(struct platform_device *pdev) goto out_pm_put; rcar_i2c_init(priv); - pm_runtime_put(dev); + + /* Don't suspend when multi-master to keep arbitration working */ + if (of_get_property(dev->of_node, "multi-master", NULL)) + priv->flags |= ID_P_PM_BLOCKED; + else + pm_runtime_put(dev); + irq = platform_get_irq(pdev, 0); ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0, dev_name(dev), priv); @@ -664,6 +673,8 @@ static int rcar_i2c_remove(struct platform_device *pdev) struct device *dev = &pdev->dev; i2c_del_adapter(&priv->adap); + if (priv->flags & ID_P_PM_BLOCKED) + pm_runtime_put(dev); pm_runtime_disable(dev); return 0; -- 2.1.4