[PATCH] Revert "ARM: OMAP: convert I2C driver to PM QoS for MPU latency constraints"
Paul Walmsley
paul at pwsan.com
Tue Nov 6 11:31:32 EST 2012
This reverts commit 3db11feffc1ad2ab9dea27789e6b5b3032827adc.
This commit causes I2C timeouts to appear on several OMAP3430/3530-based
boards:
http://marc.info/?l=linux-arm-kernel&m=135071372426971&w=2
http://marc.info/?l=linux-arm-kernel&m=135067558415214&w=2
http://marc.info/?l=linux-arm-kernel&m=135216013608196&w=2
and appears to have been sent for merging before one of its prerequisites
was merged:
http://marc.info/?l=linux-arm-kernel&m=135219411617621&w=2
Signed-off-by: Paul Walmsley <paul at pwsan.com>
Cc: Jean Pihet <jean.pihet at newoldbits.com>
Cc: Kevin Hilman <khilman at ti.com>
Cc: Aaro Koskinen <aaro.koskinen at iki.fi>
Cc: Felipe Balbi <balbi at ti.com>
---
Intended for 3.7-rc.
arch/arm/plat-omap/i2c.c | 21 +++++++++++++++++++++
drivers/i2c/busses/i2c-omap.c | 32 ++++++++++++++------------------
include/linux/i2c-omap.h | 1 +
3 files changed, 36 insertions(+), 18 deletions(-)
diff --git a/arch/arm/plat-omap/i2c.c b/arch/arm/plat-omap/i2c.c
index a5683a8..6013831 100644
--- a/arch/arm/plat-omap/i2c.c
+++ b/arch/arm/plat-omap/i2c.c
@@ -26,12 +26,14 @@
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
+#include <linux/i2c-omap.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <mach/irqs.h>
#include <plat/i2c.h>
+#include <plat/omap-pm.h>
#include <plat/omap_device.h>
#define OMAP_I2C_SIZE 0x3f
@@ -127,6 +129,16 @@ static inline int omap1_i2c_add_bus(int bus_id)
#ifdef CONFIG_ARCH_OMAP2PLUS
+/*
+ * XXX This function is a temporary compatibility wrapper - only
+ * needed until the I2C driver can be converted to call
+ * omap_pm_set_max_dev_wakeup_lat() and handle a return code.
+ */
+static void omap_pm_set_max_mpu_wakeup_lat_compat(struct device *dev, long t)
+{
+ omap_pm_set_max_mpu_wakeup_lat(dev, t);
+}
+
static inline int omap2_i2c_add_bus(int bus_id)
{
int l;
@@ -158,6 +170,15 @@ static inline int omap2_i2c_add_bus(int bus_id)
dev_attr = (struct omap_i2c_dev_attr *)oh->dev_attr;
pdata->flags = dev_attr->flags;
+ /*
+ * When waiting for completion of a i2c transfer, we need to
+ * set a wake up latency constraint for the MPU. This is to
+ * ensure quick enough wakeup from idle, when transfer
+ * completes.
+ * Only omap3 has support for constraints
+ */
+ if (cpu_is_omap34xx())
+ pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
pdev = omap_device_build(name, bus_id, oh, pdata,
sizeof(struct omap_i2c_bus_platform_data),
NULL, 0, 0);
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index db31eae..0b02543 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -43,7 +43,6 @@
#include <linux/slab.h>
#include <linux/i2c-omap.h>
#include <linux/pm_runtime.h>
-#include <linux/pm_qos.h>
/* I2C controller revisions */
#define OMAP_I2C_OMAP1_REV_2 0x20
@@ -187,8 +186,9 @@ struct omap_i2c_dev {
int reg_shift; /* bit shift for I2C register addresses */
struct completion cmd_complete;
struct resource *ioarea;
- u32 latency; /* maximum MPU wkup latency */
- struct pm_qos_request pm_qos_request;
+ u32 latency; /* maximum mpu wkup latency */
+ void (*set_mpu_wkup_lat)(struct device *dev,
+ long latency);
u32 speed; /* Speed of bus in kHz */
u32 dtrev; /* extra revision from DT */
u32 flags;
@@ -494,7 +494,9 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
dev->b_hw = 1; /* Enable hardware fixes */
/* calculate wakeup latency constraint for MPU */
- dev->latency = (1000000 * dev->threshold) / (1000 * dev->speed / 8);
+ if (dev->set_mpu_wkup_lat != NULL)
+ dev->latency = (1000000 * dev->threshold) /
+ (1000 * dev->speed / 8);
}
/*
@@ -629,16 +631,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
if (r < 0)
goto out;
- /*
- * When waiting for completion of a i2c transfer, we need to
- * set a wake up latency constraint for the MPU. This is to
- * ensure quick enough wakeup from idle, when transfer
- * completes.
- */
- if (dev->latency)
- pm_qos_add_request(&dev->pm_qos_request,
- PM_QOS_CPU_DMA_LATENCY,
- dev->latency);
+ if (dev->set_mpu_wkup_lat != NULL)
+ dev->set_mpu_wkup_lat(dev->dev, dev->latency);
for (i = 0; i < num; i++) {
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
@@ -646,8 +640,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
break;
}
- if (dev->latency)
- pm_qos_remove_request(&dev->pm_qos_request);
+ if (dev->set_mpu_wkup_lat != NULL)
+ dev->set_mpu_wkup_lat(dev->dev, -1);
if (r == 0)
r = num;
@@ -1104,6 +1098,7 @@ omap_i2c_probe(struct platform_device *pdev)
} else if (pdata != NULL) {
dev->speed = pdata->clkrate;
dev->flags = pdata->flags;
+ dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
dev->dtrev = pdata->rev;
}
@@ -1159,8 +1154,9 @@ omap_i2c_probe(struct platform_device *pdev)
dev->b_hw = 1; /* Enable hardware fixes */
/* calculate wakeup latency constraint for MPU */
- dev->latency = (1000000 * dev->fifo_size) /
- (1000 * dev->speed / 8);
+ if (dev->set_mpu_wkup_lat != NULL)
+ dev->latency = (1000000 * dev->fifo_size) /
+ (1000 * dev->speed / 8);
}
/* reset ASAP, clearing any IRQs */
diff --git a/include/linux/i2c-omap.h b/include/linux/i2c-omap.h
index df804ba..92a0dc7 100644
--- a/include/linux/i2c-omap.h
+++ b/include/linux/i2c-omap.h
@@ -34,6 +34,7 @@ struct omap_i2c_bus_platform_data {
u32 clkrate;
u32 rev;
u32 flags;
+ void (*set_mpu_wkup_lat)(struct device *dev, long set);
};
#endif
--
1.7.10.4
More information about the linux-arm-kernel
mailing list