diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-imx.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-imx.c | 58 |
1 files changed, 43 insertions, 15 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index cf1b57a054d0..117f367636b8 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -420,6 +420,19 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) /** Functions for IMX I2C adapter driver *************************************** *******************************************************************************/ +static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits) +{ + unsigned int temp; + + /* + * i2sr_clr_opcode is the value to clear all interrupts. Here we want to + * clear only <bits>, so we write ~i2sr_clr_opcode with just <bits> + * toggled. This is required because i.MX needs W0C and Vybrid uses W1C. + */ + temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); +} + static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) { unsigned long orig_jiffies = jiffies; @@ -432,8 +445,7 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) /* check for arbitration lost */ if (temp & I2SR_IAL) { - temp &= ~I2SR_IAL; - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); return -EAGAIN; } @@ -460,6 +472,16 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); return -ETIMEDOUT; } + + /* check for arbitration lost */ + if (i2c_imx->i2csr & I2SR_IAL) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__); + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); + + i2c_imx->i2csr = 0; + return -EAGAIN; + } + dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); i2c_imx->i2csr = 0; return 0; @@ -595,9 +617,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id) if (temp & I2SR_IIF) { /* save status register */ i2c_imx->i2csr = temp; - temp &= ~I2SR_IIF; - temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF); - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); + i2c_imx_clear_irq(i2c_imx, I2SR_IIF); wake_up(&i2c_imx->queue); return IRQ_HANDLED; } @@ -1076,7 +1096,8 @@ static int i2c_imx_probe(struct platform_device *pdev) /* Get I2C clock */ i2c_imx->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(i2c_imx->clk)) { - dev_err(&pdev->dev, "can't get I2C clock\n"); + if (PTR_ERR(i2c_imx->clk) != -EPROBE_DEFER) + dev_err(&pdev->dev, "can't get I2C clock\n"); return PTR_ERR(i2c_imx->clk); } @@ -1092,20 +1113,20 @@ static int i2c_imx_probe(struct platform_device *pdev) goto clk_disable; } - /* Request IRQ */ - ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0, - pdev->name, i2c_imx); - if (ret) { - dev_err(&pdev->dev, "can't claim irq %d\n", irq); - goto clk_disable; - } - /* Init queue */ init_waitqueue_head(&i2c_imx->queue); /* Set up adapter data */ i2c_set_adapdata(&i2c_imx->adapter, i2c_imx); + /* Request IRQ */ + ret = request_threaded_irq(irq, i2c_imx_isr, NULL, 0, + pdev->name, i2c_imx); + if (ret) { + dev_err(&pdev->dev, "can't claim irq %d\n", irq); + goto clk_disable; + } + /* Set up clock divider */ i2c_imx->bitrate = IMX_I2C_BIT_RATE; ret = of_property_read_u32(pdev->dev.of_node, @@ -1124,7 +1145,7 @@ static int i2c_imx_probe(struct platform_device *pdev) ret = i2c_add_numbered_adapter(&i2c_imx->adapter); if (ret < 0) { dev_err(&pdev->dev, "registration failed\n"); - goto clk_disable; + goto clk_free_irq; } /* Set up platform driver data */ @@ -1142,6 +1163,8 @@ static int i2c_imx_probe(struct platform_device *pdev) return 0; /* Return OK */ +clk_free_irq: + free_irq(irq, i2c_imx); clk_disable: clk_disable_unprepare(i2c_imx->clk); return ret; @@ -1150,6 +1173,7 @@ clk_disable: static int i2c_imx_remove(struct platform_device *pdev) { struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); + int irq; /* remove adapter */ dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n"); @@ -1164,6 +1188,10 @@ static int i2c_imx_remove(struct platform_device *pdev) imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR); + irq = platform_get_irq(pdev, 0); + if (irq >= 0) + free_irq(irq, i2c_imx); + return 0; } |