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-rw-r--r--drivers/i2c/busses/i2c-designware-baytrail.c125
1 files changed, 2 insertions, 123 deletions
diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c
index a2a275cfc1f6..b2ba4de4e204 100644
--- a/drivers/i2c/busses/i2c-designware-baytrail.c
+++ b/drivers/i2c/busses/i2c-designware-baytrail.c
@@ -3,139 +3,23 @@
* Intel BayTrail PMIC I2C bus semaphore implementaion
* Copyright (c) 2014, Intel Corporation.
*/
-#include <linux/delay.h>
#include <linux/device.h>
#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
-#include <linux/pm_qos.h>
#include <asm/iosf_mbi.h>
#include "i2c-designware-core.h"
-#define SEMAPHORE_TIMEOUT 500
-#define PUNIT_SEMAPHORE 0x7
-#define PUNIT_SEMAPHORE_CHT 0x10e
-#define PUNIT_SEMAPHORE_BIT BIT(0)
-#define PUNIT_SEMAPHORE_ACQUIRE BIT(1)
-
-static unsigned long acquired;
-
-static u32 get_sem_addr(struct dw_i2c_dev *dev)
-{
- if (dev->flags & MODEL_CHERRYTRAIL)
- return PUNIT_SEMAPHORE_CHT;
- else
- return PUNIT_SEMAPHORE;
-}
-
-static int get_sem(struct dw_i2c_dev *dev, u32 *sem)
-{
- u32 addr = get_sem_addr(dev);
- u32 data;
- int ret;
-
- ret = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, addr, &data);
- if (ret) {
- dev_err(dev->dev, "iosf failed to read punit semaphore\n");
- return ret;
- }
-
- *sem = data & PUNIT_SEMAPHORE_BIT;
-
- return 0;
-}
-
-static void reset_semaphore(struct dw_i2c_dev *dev)
-{
- if (iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ, get_sem_addr(dev),
- 0, PUNIT_SEMAPHORE_BIT))
- dev_err(dev->dev, "iosf failed to reset punit semaphore during write\n");
-
- pm_qos_update_request(&dev->pm_qos, PM_QOS_DEFAULT_VALUE);
-
- iosf_mbi_call_pmic_bus_access_notifier_chain(MBI_PMIC_BUS_ACCESS_END,
- NULL);
- iosf_mbi_punit_release();
-}
-
static int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
{
- u32 addr;
- u32 sem = PUNIT_SEMAPHORE_ACQUIRE;
- int ret;
- unsigned long start, end;
-
- might_sleep();
-
- if (!dev || !dev->dev)
- return -ENODEV;
-
- if (!dev->release_lock)
- return 0;
-
- iosf_mbi_punit_acquire();
- iosf_mbi_call_pmic_bus_access_notifier_chain(MBI_PMIC_BUS_ACCESS_BEGIN,
- NULL);
-
- /*
- * Disallow the CPU to enter C6 or C7 state, entering these states
- * requires the punit to talk to the pmic and if this happens while
- * we're holding the semaphore, the SoC hangs.
- */
- pm_qos_update_request(&dev->pm_qos, 0);
-
- addr = get_sem_addr(dev);
-
- /* host driver writes to side band semaphore register */
- ret = iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE, addr, sem);
- if (ret) {
- dev_err(dev->dev, "iosf punit semaphore request failed\n");
- goto out;
- }
-
- /* host driver waits for bit 0 to be set in semaphore register */
- start = jiffies;
- end = start + msecs_to_jiffies(SEMAPHORE_TIMEOUT);
- do {
- ret = get_sem(dev, &sem);
- if (!ret && sem) {
- acquired = jiffies;
- dev_dbg(dev->dev, "punit semaphore acquired after %ums\n",
- jiffies_to_msecs(jiffies - start));
- return 0;
- }
-
- usleep_range(1000, 2000);
- } while (time_before(jiffies, end));
-
- dev_err(dev->dev, "punit semaphore timed out, resetting\n");
-out:
- reset_semaphore(dev);
-
- ret = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, addr, &sem);
- if (ret)
- dev_err(dev->dev, "iosf failed to read punit semaphore\n");
- else
- dev_err(dev->dev, "PUNIT SEM: %d\n", sem);
-
- WARN_ON(1);
-
- return -ETIMEDOUT;
+ return iosf_mbi_block_punit_i2c_access();
}
static void baytrail_i2c_release(struct dw_i2c_dev *dev)
{
- if (!dev || !dev->dev)
- return;
-
- if (!dev->acquire_lock)
- return;
-
- reset_semaphore(dev);
- dev_dbg(dev->dev, "punit semaphore held for %ums\n",
- jiffies_to_msecs(jiffies - acquired));
+ iosf_mbi_unblock_punit_i2c_access();
}
int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
@@ -166,14 +50,9 @@ int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
dev->release_lock = baytrail_i2c_release;
dev->pm_disabled = true;
- pm_qos_add_request(&dev->pm_qos, PM_QOS_CPU_DMA_LATENCY,
- PM_QOS_DEFAULT_VALUE);
-
return 0;
}
void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev)
{
- if (dev->acquire_lock)
- pm_qos_remove_request(&dev->pm_qos);
}