[PATCH 04/13 v4] drm/i915/intel_i2c: use i2c pre/post_xfer functions to setup gpio xfers

From: Daniel Kurtz
Date: Tue Mar 27 2012 - 14:37:11 EST


Instead of rolling our own custom quirk_xfer function, use the bit_algo
pre_xfer and post_xfer functions to setup and teardown bit-banged
i2c transactions.

Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
---
drivers/gpu/drm/i915/intel_i2c.c | 60 +++++++++++++++++++++----------------
1 files changed, 34 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c
index 9347281..1bb6362 100644
--- a/drivers/gpu/drm/i915/intel_i2c.c
+++ b/drivers/gpu/drm/i915/intel_i2c.c
@@ -137,6 +137,35 @@ static void set_data(void *data, int state_high)
POSTING_READ(bus->gpio_reg);
}

+static int
+intel_gpio_pre_xfer(struct i2c_adapter *adapter)
+{
+ struct intel_gmbus *bus = container_of(adapter,
+ struct intel_gmbus,
+ adapter);
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+
+ intel_i2c_reset(dev_priv->dev);
+ intel_i2c_quirk_set(dev_priv, true);
+ set_data(bus, 1);
+ set_clock(bus, 1);
+ udelay(I2C_RISEFALL_TIME);
+ return 0;
+}
+
+static void
+intel_gpio_post_xfer(struct i2c_adapter *adapter)
+{
+ struct intel_gmbus *bus = container_of(adapter,
+ struct intel_gmbus,
+ adapter);
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+
+ set_data(bus, 1);
+ set_clock(bus, 1);
+ intel_i2c_quirk_set(dev_priv, false);
+}
+
static bool
intel_gpio_setup(struct intel_gmbus *bus, u32 pin)
{
@@ -166,6 +195,8 @@ intel_gpio_setup(struct intel_gmbus *bus, u32 pin)
algo->setscl = set_clock;
algo->getsda = get_data;
algo->getscl = get_clock;
+ algo->pre_xfer = intel_gpio_pre_xfer;
+ algo->post_xfer = intel_gpio_post_xfer;
algo->udelay = I2C_RISEFALL_TIME;
algo->timeout = usecs_to_jiffies(2200);
algo->data = bus;
@@ -174,30 +205,6 @@ intel_gpio_setup(struct intel_gmbus *bus, u32 pin)
}

static int
-intel_i2c_quirk_xfer(struct intel_gmbus *bus,
- struct i2c_msg *msgs,
- int num)
-{
- struct drm_i915_private *dev_priv = bus->dev_priv;
- int ret;
-
- intel_i2c_reset(dev_priv->dev);
-
- intel_i2c_quirk_set(dev_priv, true);
- set_data(bus, 1);
- set_clock(bus, 1);
- udelay(I2C_RISEFALL_TIME);
-
- ret = i2c_bit_algo.master_xfer(&bus->adapter, msgs, num);
-
- set_data(bus, 1);
- set_clock(bus, 1);
- intel_i2c_quirk_set(dev_priv, false);
-
- return ret;
-}
-
-static int
gmbus_xfer_read(struct drm_i915_private *dev_priv, struct i2c_msg *msg,
bool last)
{
@@ -287,7 +294,7 @@ gmbus_xfer(struct i2c_adapter *adapter,
mutex_lock(&dev_priv->gmbus_mutex);

if (bus->force_bit) {
- ret = intel_i2c_quirk_xfer(bus, msgs, num);
+ ret = i2c_bit_algo.master_xfer(adapter, msgs, num);
goto out;
}

@@ -351,8 +358,9 @@ timeout:
ret = -EIO;
} else {
bus->force_bit = true;
- ret = intel_i2c_quirk_xfer(bus, msgs, num);
+ ret = i2c_bit_algo.master_xfer(adapter, msgs, num);
}
+
out:
mutex_unlock(&dev_priv->gmbus_mutex);
return ret;
--
1.7.7.3

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