#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
-#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
#include <plat/i2c.h>
/* 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,
I2C_READ = 0x01
};
-/* controller response timeout in ms */
-#define I2C_TIMEOUT_MS 2000
-
/**
* struct i2c_nmk_client - client specific data
* @slave_adr: 7-bit slave address
* @stop: stop condition
* @xfer_complete: acknowledge completion for a I2C message
* @result: controller propogated result
+ * @busy: Busy doing transfer
*/
struct nmk_i2c_dev {
struct platform_device *pdev;
int stop;
struct completion xfer_complete;
int result;
+ struct regulator *regulator;
+ bool busy;
};
/* controller's abort causes */
writel((I2C_CR_FTX | I2C_CR_FRX), dev->virtbase + I2C_CR);
for (i = 0; i < LOOP_ATTEMPTS; i++) {
- timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT_MS);
+ timeout = jiffies + dev->adap.timeout;
while (!time_after(jiffies, timeout)) {
if ((readl(dev->virtbase + I2C_CR) &
{
int stat;
- clk_enable(dev->clk);
-
stat = flush_i2c_fifo(dev);
if (stat)
- return stat;
+ goto exit;
/* disable the controller */
i2c_clr_bit(dev->virtbase + I2C_CR , I2C_CR_PE);
dev->cli.operation = I2C_NO_OPERATION;
- clk_disable(dev->clk);
-
- udelay(I2C_DELAY);
- return 0;
+exit:
+ return stat;
}
/* enable peripheral, master mode operation */
dev->virtbase + I2C_IMSCR);
timeout = wait_for_completion_interruptible_timeout(
- &dev->xfer_complete, msecs_to_jiffies(I2C_TIMEOUT_MS));
+ &dev->xfer_complete, dev->adap.timeout);
if (timeout < 0) {
dev_err(&dev->pdev->dev,
}
if (timeout == 0) {
- /* controller has timedout, re-init the h/w */
- dev_err(&dev->pdev->dev, "controller timed out, re-init h/w\n");
- (void) init_hw(dev);
+ /* Controller timed out */
+ dev_err(&dev->pdev->dev, "read from slave 0x%x timed out\n",
+ dev->cli.slave_adr);
status = -ETIMEDOUT;
}
return status;
}
+static void fill_tx_fifo(struct nmk_i2c_dev *dev, int no_bytes)
+{
+ int count;
+
+ for (count = (no_bytes - 2);
+ (count > 0) &&
+ (dev->cli.count != 0);
+ count--) {
+ /* write to the Tx FIFO */
+ writeb(*dev->cli.buffer,
+ dev->virtbase + I2C_TFR);
+ dev->cli.buffer++;
+ dev->cli.count--;
+ dev->cli.xfer_bytes++;
+ }
+
+}
+
/**
* write_i2c() - Write data to I2C client.
* @dev: private data of I2C Driver
init_completion(&dev->xfer_complete);
/* enable interrupts by settings the masks */
- irq_mask = (I2C_IT_TXFNE | I2C_IT_TXFOVR |
- I2C_IT_MAL | I2C_IT_BERR);
+ irq_mask = (I2C_IT_TXFOVR | I2C_IT_MAL | I2C_IT_BERR);
+
+ /* Fill the TX FIFO with transmit data */
+ fill_tx_fifo(dev, MAX_I2C_FIFO_THRESHOLD);
+
+ if (dev->cli.count != 0)
+ irq_mask |= I2C_IT_TXFNE;
/*
* check if we want to transfer a single or multiple bytes, if so
dev->virtbase + I2C_IMSCR);
timeout = wait_for_completion_interruptible_timeout(
- &dev->xfer_complete, msecs_to_jiffies(I2C_TIMEOUT_MS));
+ &dev->xfer_complete, dev->adap.timeout);
if (timeout < 0) {
dev_err(&dev->pdev->dev,
}
if (timeout == 0) {
- /* controller has timedout, re-init the h/w */
- dev_err(&dev->pdev->dev, "controller timed out, re-init h/w\n");
- (void) init_hw(dev);
+ /* Controller timed out */
+ dev_err(&dev->pdev->dev, "write to slave 0x%x timed out\n",
+ dev->cli.slave_adr);
status = -ETIMEDOUT;
}
return status;
}
+/**
+ * nmk_i2c_xfer_one() - transmit a single I2C message
+ * @dev: device with a message encoded into it
+ * @flags: message flags
+ */
+static int nmk_i2c_xfer_one(struct nmk_i2c_dev *dev, u16 flags)
+{
+ int status;
+
+ if (flags & I2C_M_RD) {
+ /* read operation */
+ dev->cli.operation = I2C_READ;
+ status = read_i2c(dev);
+ } else {
+ /* write operation */
+ dev->cli.operation = I2C_WRITE;
+ status = write_i2c(dev);
+ }
+
+ if (status || (dev->result)) {
+ u32 i2c_sr;
+ u32 cause;
+
+ i2c_sr = readl(dev->virtbase + I2C_SR);
+ /*
+ * Check if the controller I2C operation status
+ * is set to ABORT(11b).
+ */
+ if (((i2c_sr >> 2) & 0x3) == 0x3) {
+ /* get the abort cause */
+ cause = (i2c_sr >> 4) & 0x7;
+ dev_err(&dev->pdev->dev, "%s\n", cause
+ >= ARRAY_SIZE(abort_causes) ?
+ "unknown reason" :
+ abort_causes[cause]);
+ }
+
+ (void) init_hw(dev);
+
+ status = status ? status : dev->result;
+ }
+
+ return status;
+}
+
/**
* nmk_i2c_xfer() - I2C transfer function used by kernel framework
* @i2c_adap: Adapter pointer to the controller
{
int status;
int i;
- u32 cause;
struct nmk_i2c_dev *dev = i2c_get_adapdata(i2c_adap);
+ int j;
+
+ dev->busy = true;
+
+ if (dev->regulator)
+ regulator_enable(dev->regulator);
+ pm_runtime_get_sync(&dev->pdev->dev);
+
+ clk_enable(dev->clk);
status = init_hw(dev);
if (status)
- return status;
+ goto out;
- clk_enable(dev->clk);
+ /* Attempt three times to send the message queue */
+ for (j = 0; j < 3; j++) {
+ /* setup the i2c controller */
+ setup_i2c_controller(dev);
- /* setup the i2c controller */
- setup_i2c_controller(dev);
+ for (i = 0; i < num_msgs; i++) {
+ if (unlikely(msgs[i].flags & I2C_M_TEN)) {
+ dev_err(&dev->pdev->dev, "10 bit addressing"
+ "not supported\n");
- for (i = 0; i < num_msgs; i++) {
- if (unlikely(msgs[i].flags & I2C_M_TEN)) {
- dev_err(&dev->pdev->dev, "10 bit addressing"
- "not supported\n");
- return -EINVAL;
- }
- dev->cli.slave_adr = msgs[i].addr;
- dev->cli.buffer = msgs[i].buf;
- dev->cli.count = msgs[i].len;
- dev->stop = (i < (num_msgs - 1)) ? 0 : 1;
- dev->result = 0;
-
- if (msgs[i].flags & I2C_M_RD) {
- /* it is a read operation */
- dev->cli.operation = I2C_READ;
- status = read_i2c(dev);
- } else {
- /* write operation */
- dev->cli.operation = I2C_WRITE;
- status = write_i2c(dev);
- }
- if (status || (dev->result)) {
- /* get the abort cause */
- cause = (readl(dev->virtbase + I2C_SR) >> 4) & 0x7;
- dev_err(&dev->pdev->dev, "error during I2C"
- "message xfer: %d\n", cause);
- dev_err(&dev->pdev->dev, "%s\n",
- cause >= ARRAY_SIZE(abort_causes)
- ? "unknown reason" : abort_causes[cause]);
- clk_disable(dev->clk);
- return status;
+ status = -EINVAL;
+ goto out;
+ }
+ dev->cli.slave_adr = msgs[i].addr;
+ dev->cli.buffer = msgs[i].buf;
+ dev->cli.count = msgs[i].len;
+ dev->stop = (i < (num_msgs - 1)) ? 0 : 1;
+ dev->result = 0;
+
+ status = nmk_i2c_xfer_one(dev, msgs[i].flags);
+ if (status != 0)
+ break;
}
- udelay(I2C_DELAY);
+ if (status == 0)
+ break;
}
+
+out:
clk_disable(dev->clk);
+ pm_runtime_put_sync(&dev->pdev->dev);
+ if (dev->regulator)
+ regulator_disable(dev->regulator);
+
+ dev->busy = false;
/* return the no. messages processed */
if (status)
*/
disable_interrupts(dev, I2C_IT_TXFNE);
} else {
- for (count = (MAX_I2C_FIFO_THRESHOLD - tft - 2);
- (count > 0) &&
- (dev->cli.count != 0);
- count--) {
- /* write to the Tx FIFO */
- writeb(*dev->cli.buffer,
- dev->virtbase + I2C_TFR);
- dev->cli.buffer++;
- dev->cli.count--;
- dev->cli.xfer_bytes++;
- }
+ fill_tx_fifo(dev, (MAX_I2C_FIFO_THRESHOLD - tft));
/*
* if done, close the transfer by disabling the
* corresponding TXFNE interrupt
}
}
- i2c_set_bit(dev->virtbase + I2C_ICR, I2C_IT_MTD);
- i2c_set_bit(dev->virtbase + I2C_ICR, I2C_IT_MTDWS);
-
- disable_interrupts(dev,
- (I2C_IT_TXFNE | I2C_IT_TXFE | I2C_IT_TXFF
- | I2C_IT_TXFOVR | I2C_IT_RXFNF
- | I2C_IT_RXFF | I2C_IT_RXFE));
+ disable_all_interrupts(dev);
+ clear_all_interrupts(dev);
if (dev->cli.count) {
- dev->result = -1;
+ dev->result = -EIO;
dev_err(&dev->pdev->dev, "%lu bytes still remain to be"
"xfered\n", dev->cli.count);
(void) init_hw(dev);
/* Master Arbitration lost interrupt */
case I2C_IT_MAL:
- dev->result = -1;
+ dev->result = -EIO;
(void) init_hw(dev);
i2c_set_bit(dev->virtbase + I2C_ICR, I2C_IT_MAL);
* during the transaction.
*/
case I2C_IT_BERR:
- dev->result = -1;
+ dev->result = -EIO;
/* get the status */
if (((readl(dev->virtbase + I2C_SR) >> 2) & 0x3) == I2C_ABORT)
(void) init_hw(dev);
* the Tx FIFO is full.
*/
case I2C_IT_TXFOVR:
- dev->result = -1;
+ dev->result = -EIO;
(void) init_hw(dev);
dev_err(&dev->pdev->dev, "Tx Fifo Over run\n");
return IRQ_HANDLED;
}
+
+#ifdef CONFIG_PM
+static int nmk_i2c_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct nmk_i2c_dev *nmk_i2c = platform_get_drvdata(pdev);
+
+ if (nmk_i2c->busy)
+ return -EBUSY;
+
+ return 0;
+}
+
+static int nmk_i2c_resume(struct device *dev)
+{
+ return 0;
+}
+#else
+#define nmk_i2c_suspend NULL
+#define nmk_i2c_resume NULL
+#endif
+
+/*
+ * We use noirq so that we suspend late and resume before the wakeup interrupt
+ * to ensure that we do the !pm_runtime_suspended() check in resume before
+ * there has been a regular pm runtime resume (via pm_runtime_get_sync()).
+ */
+static const struct dev_pm_ops nmk_i2c_pm = {
+ .suspend_noirq = nmk_i2c_suspend,
+ .resume_noirq = nmk_i2c_resume,
+};
+
static unsigned int nmk_i2c_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
ret = -ENOMEM;
goto err_no_mem;
}
-
+ dev->busy = false;
dev->pdev = pdev;
platform_set_drvdata(pdev, dev);
goto err_irq;
}
+ dev->regulator = regulator_get(&pdev->dev, "v-i2c");
+ if (IS_ERR(dev->regulator)) {
+ dev_warn(&pdev->dev, "could not get i2c regulator\n");
+ dev->regulator = NULL;
+ }
+
+ pm_suspend_ignore_children(&pdev->dev, true);
+ pm_runtime_enable(&pdev->dev);
+
dev->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk)) {
dev_err(&pdev->dev, "could not get i2c clock\n");
adap->owner = THIS_MODULE;
adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
adap->algo = &nmk_i2c_algo;
+ adap->timeout = pdata->timeout ? msecs_to_jiffies(pdata->timeout) :
+ msecs_to_jiffies(20000);
snprintf(adap->name, sizeof(adap->name),
"Nomadik I2C%d at %lx", pdev->id, (unsigned long)res->start);
i2c_set_adapdata(adap, dev);
- ret = init_hw(dev);
- if (ret != 0) {
- dev_err(&pdev->dev, "error in initializing i2c hardware\n");
- goto err_init_hw;
- }
-
dev_info(&pdev->dev, "initialize %s on virtual "
"base %p\n", adap->name, dev->virtbase);
return 0;
- err_init_hw:
err_add_adap:
clk_put(dev->clk);
err_no_clk:
+ if (dev->regulator)
+ regulator_put(dev->regulator);
+ pm_runtime_disable(&pdev->dev);
free_irq(dev->irq, dev);
err_irq:
iounmap(dev->virtbase);
if (res)
release_mem_region(res->start, resource_size(res));
clk_put(dev->clk);
+ if (dev->regulator)
+ regulator_put(dev->regulator);
+ pm_runtime_disable(&pdev->dev);
platform_set_drvdata(pdev, NULL);
kfree(dev);
.driver = {
.owner = THIS_MODULE,
.name = DRIVER_NAME,
+ .pm = &nmk_i2c_pm,
},
.probe = nmk_i2c_probe,
.remove = __devexit_p(nmk_i2c_remove),
git.openpandora.org / pandora-kernel.git / blobdiff