Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "A set of updates and bugfixes for the new designware-baytrail driver.

  And a documentation bugfix"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: imx: add required clocks property to binding
  i2c: designware-baytrail: baytrail_i2c_acquire() might sleep
  i2c: designware-baytrail: cross-check lock functions
  i2c: designware-baytrail: fix sparse warnings
  i2c: designware-baytrail: fix typo in error path
  i2c: designware-baytrail: describe magic numbers
This commit is contained in:
Linus Torvalds 2015-03-07 11:56:30 -08:00
commit 2cf3afcd4c
2 changed files with 22 additions and 19 deletions

View File

@ -7,6 +7,7 @@ Required properties:
- "fsl,vf610-i2c" for I2C compatible with the one integrated on Vybrid vf610 SoC
- reg : Should contain I2C/HS-I2C registers location and length
- interrupts : Should contain I2C/HS-I2C interrupt
- clocks : Should contain the I2C/HS-I2C clock specifier
Optional properties:
- clock-frequency : Constains desired I2C/HS-I2C bus clock frequency in Hz.

View File

@ -17,27 +17,31 @@
#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <asm/iosf_mbi.h>
#include "i2c-designware-core.h"
#define SEMAPHORE_TIMEOUT 100
#define PUNIT_SEMAPHORE 0x7
#define PUNIT_SEMAPHORE_BIT BIT(0)
#define PUNIT_SEMAPHORE_ACQUIRE BIT(1)
static unsigned long acquired;
static int get_sem(struct device *dev, u32 *sem)
{
u32 reg_val;
u32 data;
int ret;
ret = iosf_mbi_read(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_READ, PUNIT_SEMAPHORE,
&reg_val);
&data);
if (ret) {
dev_err(dev, "iosf failed to read punit semaphore\n");
return ret;
}
*sem = reg_val & 0x1;
*sem = data & PUNIT_SEMAPHORE_BIT;
return 0;
}
@ -52,27 +56,29 @@ static void reset_semaphore(struct device *dev)
return;
}
data = data & 0xfffffffe;
data &= ~PUNIT_SEMAPHORE_BIT;
if (iosf_mbi_write(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_WRITE,
PUNIT_SEMAPHORE, data))
PUNIT_SEMAPHORE, data))
dev_err(dev, "iosf failed to reset punit semaphore during write\n");
}
int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
static int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
{
u32 sem = 0;
u32 sem;
int ret;
unsigned long start, end;
might_sleep();
if (!dev || !dev->dev)
return -ENODEV;
if (!dev->acquire_lock)
if (!dev->release_lock)
return 0;
/* host driver writes 0x2 to side band semaphore register */
/* host driver writes to side band semaphore register */
ret = iosf_mbi_write(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_WRITE,
PUNIT_SEMAPHORE, 0x2);
PUNIT_SEMAPHORE, PUNIT_SEMAPHORE_ACQUIRE);
if (ret) {
dev_err(dev->dev, "iosf punit semaphore request failed\n");
return ret;
@ -81,7 +87,7 @@ int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
/* host driver waits for bit 0 to be set in semaphore register */
start = jiffies;
end = start + msecs_to_jiffies(SEMAPHORE_TIMEOUT);
while (!time_after(jiffies, end)) {
do {
ret = get_sem(dev->dev, &sem);
if (!ret && sem) {
acquired = jiffies;
@ -91,14 +97,14 @@ int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
}
usleep_range(1000, 2000);
}
} while (time_before(jiffies, end));
dev_err(dev->dev, "punit semaphore timed out, resetting\n");
reset_semaphore(dev->dev);
ret = iosf_mbi_read(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_READ,
PUNIT_SEMAPHORE, &sem);
if (!ret)
PUNIT_SEMAPHORE, &sem);
if (ret)
dev_err(dev->dev, "iosf failed to read punit semaphore\n");
else
dev_err(dev->dev, "PUNIT SEM: %d\n", sem);
@ -107,9 +113,8 @@ int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
return -ETIMEDOUT;
}
EXPORT_SYMBOL(baytrail_i2c_acquire);
void baytrail_i2c_release(struct dw_i2c_dev *dev)
static void baytrail_i2c_release(struct dw_i2c_dev *dev)
{
if (!dev || !dev->dev)
return;
@ -121,7 +126,6 @@ void baytrail_i2c_release(struct dw_i2c_dev *dev)
dev_dbg(dev->dev, "punit semaphore held for %ums\n",
jiffies_to_msecs(jiffies - acquired));
}
EXPORT_SYMBOL(baytrail_i2c_release);
int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev)
{
@ -137,7 +141,6 @@ int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev)
return 0;
status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
if (ACPI_FAILURE(status))
return 0;
@ -153,7 +156,6 @@ int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev)
return 0;
}
EXPORT_SYMBOL(i2c_dw_eval_lock_support);
MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
MODULE_DESCRIPTION("Baytrail I2C Semaphore driver");