diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-nomadik.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-nomadik.c | 36 |
1 files changed, 21 insertions, 15 deletions
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c index 73de8ade10b..c9fffd0389f 100644 --- a/drivers/i2c/busses/i2c-nomadik.c +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2009 ST-Ericsson + * Copyright (C) 2009 ST-Ericsson SA * Copyright (C) 2009 STMicroelectronics * * I2C master mode controller driver, used in Nomadik 8815 @@ -103,6 +103,9 @@ /* maximum threshold value */ #define MAX_I2C_FIFO_THRESHOLD 15 +/* per-transfer delay, required for the hardware to stabilize */ +#define I2C_DELAY 150 + enum i2c_status { I2C_NOP, I2C_ON_GOING, @@ -118,7 +121,7 @@ enum i2c_operation { }; /* controller response timeout in ms */ -#define I2C_TIMEOUT_MS 500 +#define I2C_TIMEOUT_MS 2000 /** * struct i2c_nmk_client - client specific data @@ -250,6 +253,8 @@ static int init_hw(struct nmk_i2c_dev *dev) { int stat; + clk_enable(dev->clk); + stat = flush_i2c_fifo(dev); if (stat) return stat; @@ -263,6 +268,9 @@ static int init_hw(struct nmk_i2c_dev *dev) dev->cli.operation = I2C_NO_OPERATION; + clk_disable(dev->clk); + + udelay(I2C_DELAY); return 0; } @@ -431,7 +439,6 @@ static int read_i2c(struct nmk_i2c_dev *dev) (void) init_hw(dev); status = -ETIMEDOUT; } - return status; } @@ -502,9 +509,9 @@ static int write_i2c(struct nmk_i2c_dev *dev) /** * nmk_i2c_xfer() - I2C transfer function used by kernel framework - * @i2c_adap - Adapter pointer to the controller - * @msgs[] - Pointer to data to be written. - * @num_msgs - Number of messages to be executed + * @i2c_adap: Adapter pointer to the controller + * @msgs: Pointer to data to be written. + * @num_msgs: Number of messages to be executed * * This is the function called by the generic kernel i2c_transfer() * or i2c_smbus...() API calls. Note that this code is protected by the @@ -559,6 +566,8 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, if (status) return status; + clk_enable(dev->clk); + /* setup the i2c controller */ setup_i2c_controller(dev); @@ -591,10 +600,13 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, dev_err(&dev->pdev->dev, "%s\n", cause >= ARRAY_SIZE(abort_causes) ? "unknown reason" : abort_causes[cause]); + clk_disable(dev->clk); return status; } - mdelay(1); + udelay(I2C_DELAY); } + clk_disable(dev->clk); + /* return the no. messages processed */ if (status) return status; @@ -605,6 +617,7 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, /** * disable_interrupts() - disable the interrupts * @dev: private data of controller + * @irq: interrupt number */ static int disable_interrupts(struct nmk_i2c_dev *dev, u32 irq) { @@ -794,10 +807,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg) static unsigned int nmk_i2c_functionality(struct i2c_adapter *adap) { - return I2C_FUNC_I2C - | I2C_FUNC_SMBUS_BYTE_DATA - | I2C_FUNC_SMBUS_WORD_DATA - | I2C_FUNC_SMBUS_I2C_BLOCK; + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; } static const struct i2c_algorithm nmk_i2c_algo = { @@ -857,8 +867,6 @@ static int __devinit nmk_i2c_probe(struct platform_device *pdev) goto err_no_clk; } - clk_enable(dev->clk); - adap = &dev->adap; adap->dev.parent = &pdev->dev; adap->owner = THIS_MODULE; @@ -895,7 +903,6 @@ static int __devinit nmk_i2c_probe(struct platform_device *pdev) return 0; err_init_hw: - clk_disable(dev->clk); err_add_adap: clk_put(dev->clk); err_no_clk: @@ -928,7 +935,6 @@ static int __devexit nmk_i2c_remove(struct platform_device *pdev) iounmap(dev->virtbase); if (res) release_mem_region(res->start, resource_size(res)); - clk_disable(dev->clk); clk_put(dev->clk); platform_set_drvdata(pdev, NULL); kfree(dev); |