From f6f808c8e1c4a3b7e3e0a6cb81541ec615aeb5fd Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Tue, 14 Feb 2012 18:58:49 +0100 Subject: [PATCH] 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: Eugeni Dodonov Signed-Off-by: Daniel Vetter --- 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 47b315c..c0f19f57 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -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; diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c index 43dde95..8fdc957 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_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) -- 2.7.4