[PATCH] drm/i915: i2c: unconditionally set up gpio fallback
Daniel Vetter
daniel.vetter at ffwll.ch
Mon Feb 27 10:22:43 PST 2012
This way we can simplify the setup and teardown a bit.
Because we don't actually allocate anything anymore for the force_bit
case, we can now convert that into a boolean.
Also and the functionality supported by the bit-banging together with
what gmbus can do, so that this doesn't randomly change any more.
v2: Chris Wilson noticed that I've mixed up && and & ...
v3: Clarify an if block as suggested by Eugeni Dodonov.
Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
drivers/gpu/drm/i915/i915_drv.h | 3 +-
drivers/gpu/drm/i915/intel_i2c.c | 51 +++++++++++++++-----------------------
2 files changed, 22 insertions(+), 32 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 14b6e94..31affc0 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -293,7 +293,8 @@ struct intel_fbc_work;
struct intel_gmbus {
struct i2c_adapter adapter;
- struct i2c_adapter *force_bit;
+ bool force_bit;
+ bool has_gpio;
u32 reg0;
u32 gpio_reg;
struct i2c_algo_bit_data bit_algo;
diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c
index 6eb68b7..44d1755 100644
--- a/drivers/gpu/drm/i915/intel_i2c.c
+++ b/drivers/gpu/drm/i915/intel_i2c.c
@@ -140,8 +140,8 @@ static void set_data(void *data, int state_high)
POSTING_READ(bus->gpio_reg);
}
-static struct i2c_adapter *
-intel_gpio_create(struct intel_gmbus *bus, u32 pin)
+static bool
+intel_gpio_setup(struct intel_gmbus *bus, u32 pin)
{
struct drm_i915_private *dev_priv = bus->dev_priv;
static const int map_pin_to_reg[] = {
@@ -157,7 +157,7 @@ intel_gpio_create(struct intel_gmbus *bus, u32 pin)
struct i2c_algo_bit_data *algo;
if (pin >= ARRAY_SIZE(map_pin_to_reg) || !map_pin_to_reg[pin])
- return NULL;
+ return false;
algo = &bus->bit_algo;
@@ -174,12 +174,11 @@ intel_gpio_create(struct intel_gmbus *bus, u32 pin)
algo->timeout = usecs_to_jiffies(2200);
algo->data = bus;
- return &bus->adapter;
+ return true;
}
static int
intel_i2c_quirk_xfer(struct intel_gmbus *bus,
- struct i2c_adapter *adapter,
struct i2c_msg *msgs,
int num)
{
@@ -193,7 +192,7 @@ intel_i2c_quirk_xfer(struct intel_gmbus *bus,
set_clock(bus, 1);
udelay(I2C_RISEFALL_TIME);
- ret = i2c_bit_xfer(adapter, msgs, num);
+ ret = i2c_bit_xfer(&bus->adapter, msgs, num);
set_data(bus, 1);
set_clock(bus, 1);
@@ -216,7 +215,7 @@ gmbus_xfer(struct i2c_adapter *adapter,
mutex_lock(&dev_priv->gmbus_mutex);
if (bus->force_bit) {
- ret = intel_i2c_quirk_xfer(bus, bus->force_bit, msgs, num);
+ ret = intel_i2c_quirk_xfer(bus, msgs, num);
goto out;
}
@@ -311,11 +310,12 @@ timeout:
I915_WRITE(GMBUS0 + reg_offset, 0);
/* Hardware may not support GMBUS over these pins? Try GPIO bitbanging instead. */
- bus->force_bit = intel_gpio_create(bus, bus->reg0 & 0xff);
- if (!bus->force_bit)
- ret = -ENOMEM;
- else
- ret = intel_i2c_quirk_xfer(bus, bus->force_bit, msgs, num);
+ if (!bus->has_gpio) {
+ ret = -EIO;
+ } else {
+ bus->force_bit = true;
+ ret = intel_i2c_quirk_xfer(bus, msgs, num);
+ }
out:
mutex_unlock(&dev_priv->gmbus_mutex);
return ret;
@@ -323,14 +323,8 @@ out:
static u32 gmbus_func(struct i2c_adapter *adapter)
{
- struct intel_gmbus *bus = container_of(adapter,
- struct intel_gmbus,
- adapter);
-
- if (bus->force_bit)
- i2c_bit_func(bus->force_bit);
-
- return (I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+ return i2c_bit_func(adapter) &
+ (I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
/* I2C_FUNC_10BIT_ADDR | */
I2C_FUNC_SMBUS_READ_BLOCK_DATA |
I2C_FUNC_SMBUS_BLOCK_PROC_CALL);
@@ -388,8 +382,11 @@ int intel_setup_gmbus(struct drm_device *dev)
/* By default use a conservative clock rate */
bus->reg0 = i | GMBUS_RATE_100KHZ;
+ bus->has_gpio = intel_gpio_setup(bus, i);
+
/* XXX force bit banging until GMBUS is fully debugged */
- bus->force_bit = intel_gpio_create(bus, i);
+ if (bus->has_gpio)
+ bus->force_bit = true;
}
intel_i2c_reset(dev_priv->dev);
@@ -417,16 +414,8 @@ void intel_gmbus_force_bit(struct i2c_adapter *adapter, bool force_bit)
{
struct intel_gmbus *bus = to_intel_gmbus(adapter);
- if (force_bit) {
- if (bus->force_bit == NULL) {
- bus->force_bit = intel_gpio_create(bus,
- bus->reg0 & 0xff);
- }
- } else {
- if (bus->force_bit) {
- bus->force_bit = NULL;
- }
- }
+ if (bus->has_gpio)
+ bus->force_bit = force_bit;
}
void intel_teardown_gmbus(struct drm_device *dev)
--
1.7.7.5
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