From 968061f69b9e2e55eb3c291d442a4e90e8334433 Mon Sep 17 00:00:00 2001 From: Zhijun He Date: Thu, 30 Jun 2011 17:16:02 -0700 Subject: Revert "i2c: tegra: Remove the synchronization between isr and caller" This reverts commit fbe412ed91158bc1ec5c30c1bc9e9857a115d754. This fixed the video recording system hang bug. Bug 842901 Change-Id: I9467931ffe57b0d7462f6ca09f7582f9c3c40e46 Reviewed-on: http://git-master/r/39286 Tested-by: Zhijun He Reviewed-by: Jeremy Wyman --- drivers/i2c/busses/i2c-tegra.c | 43 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 37 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index c8a26a85a938..f9a14a75563c 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -31,6 +31,7 @@ #include #include #include +#include #include @@ -125,10 +126,12 @@ struct tegra_i2c_dev { struct clk *clk; struct resource *iomem; struct rt_mutex dev_lock; + spinlock_t clk_lock; void __iomem *base; int cont_id; int irq; bool irq_disabled; + bool controller_enabled; int is_dvc; bool is_slave; struct completion msg_complete; @@ -385,6 +388,14 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) u32 status; const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST | I2C_INT_TX_FIFO_OVERFLOW; struct tegra_i2c_dev *i2c_dev = dev_id; + unsigned long flags; + + spin_lock_irqsave(&i2c_dev->clk_lock, flags); + if (!i2c_dev->controller_enabled) { + dev_warn(i2c_dev->dev, "Controller not enabled\n"); + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); + return IRQ_NONE; + } status = i2c_readl(i2c_dev, I2C_INT_STATUS); @@ -398,7 +409,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) i2c_dev->irq_disabled = 1; } - complete(&i2c_dev->msg_complete); goto err; } @@ -427,8 +437,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) dev_warn(i2c_dev->dev, "Packet status 0x%08x\n", i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS)); } - complete(&i2c_dev->msg_complete); - goto err; } @@ -444,7 +452,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) i2c_dev->irq_disabled = 1; } - complete(&i2c_dev->msg_complete); goto err; } @@ -465,13 +472,15 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) if (status & I2C_INT_PACKET_XFER_COMPLETE) i2c_dev->msg_transfer_complete = 1; - if (i2c_dev->msg_transfer_complete && !i2c_dev->msg_buf_remaining) - complete(&i2c_dev->msg_complete); i2c_writel(i2c_dev, status, I2C_INT_STATUS); if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + if (i2c_dev->msg_transfer_complete && !i2c_dev->msg_buf_remaining) + complete(&i2c_dev->msg_complete); + + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); return IRQ_HANDLED; err: @@ -505,6 +514,8 @@ err: if (i2c_dev->is_dvc) dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + complete(&i2c_dev->msg_complete); + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); return IRQ_HANDLED; } @@ -514,6 +525,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_bus *i2c_bus, struct tegra_i2c_dev *i2c_dev = i2c_bus->dev; u32 int_mask; int ret; + unsigned long flags; tegra_i2c_flush_fifos(i2c_dev); @@ -570,7 +582,10 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_bus *i2c_bus, "i2c transfer timed out, addr 0x%04x, data 0x%02x\n", msg->addr, msg->buf[0]); + spin_lock_irqsave(&i2c_dev->clk_lock, flags); + i2c_dev->controller_enabled = false; tegra_i2c_init(i2c_dev); + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); return -ETIMEDOUT; } @@ -580,7 +595,11 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_bus *i2c_bus, if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) return 0; + spin_lock_irqsave(&i2c_dev->clk_lock, flags); + i2c_dev->controller_enabled = false; tegra_i2c_init(i2c_dev); + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) return 0; @@ -600,6 +619,7 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], struct tegra_i2c_dev *i2c_dev = i2c_bus->dev; int i; int ret = 0; + unsigned long flags; if (i2c_dev->is_suspended) return -EBUSY; @@ -625,6 +645,11 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], if (!i2c_dev->is_clkon_always) clk_enable(i2c_dev->clk); + + spin_lock_irqsave(&i2c_dev->clk_lock, flags); + i2c_dev->controller_enabled = true; + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); + for (i = 0; i < num; i++) { int stop = (i == (num - 1)) ? 1 : 0; ret = tegra_i2c_xfer_msg(i2c_bus, &msgs[i], stop); @@ -634,6 +659,10 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], ret = i; out: + spin_lock_irqsave(&i2c_dev->clk_lock, flags); + i2c_dev->controller_enabled = false; + spin_unlock_irqrestore(&i2c_dev->clk_lock, flags); + if (!i2c_dev->is_clkon_always) clk_disable(i2c_dev->clk); @@ -731,7 +760,9 @@ static int tegra_i2c_probe(struct platform_device *pdev) i2c_dev->last_bus_clk = plat->bus_clk_rate[0] ?: 100000; i2c_dev->msgs = NULL; i2c_dev->msgs_num = 0; + i2c_dev->controller_enabled = false; rt_mutex_init(&i2c_dev->dev_lock); + spin_lock_init(&i2c_dev->clk_lock); i2c_dev->slave_addr = plat->slave_addr; i2c_dev->is_dvc = plat->is_dvc; -- cgit v1.2.3