Commit f6f808c8 authored by Daniel Vetter's avatar Daniel Vetter
Browse files

drm/i915: i2c: unconditionally set up gpio fallback 



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.

Reviewed-by: default avatarEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent c167a6fc

drivers/gpu/drm/i915/i915_drv.h

+2 −1
Original line number Diff line number Diff line
@@ -301,7 +301,8 @@ 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;

drivers/gpu/drm/i915/intel_i2c.c

+20 −31
Original line number Diff line number Diff line
@@ -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_algo.master_xfer(adapter, msgs, num);

	ret = i2c_bit_algo.master_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;

	}
@@ -316,11 +315,12 @@ 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;
@@ -328,14 +328,8 @@ 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_algo.functionality(bus->force_bit);



	return (I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |

	return i2c_bit_algo.functionality(adapter) &

		(I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |

		/* I2C_FUNC_10BIT_ADDR | */

		I2C_FUNC_SMBUS_READ_BLOCK_DATA |

		I2C_FUNC_SMBUS_BLOCK_PROC_CALL);
@@ -393,8 +387,11 @@ 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);
@@ -422,16 +419,8 @@ 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)

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