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path: root/drivers/gpu/drm/i915/intel_i2c.c
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Diffstat (limited to 'drivers/gpu/drm/i915/intel_i2c.c')
-rw-r--r--drivers/gpu/drm/i915/intel_i2c.c381
1 files changed, 268 insertions, 113 deletions
diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c
index d3d65a9cfba1..6f4d128935ac 100644
--- a/drivers/gpu/drm/i915/intel_i2c.c
+++ b/drivers/gpu/drm/i915/intel_i2c.c
@@ -1,6 +1,6 @@
/*
* Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
- * Copyright © 2006-2008 Intel Corporation
+ * Copyright © 2006-2008,2010 Intel Corporation
* Jesse Barnes <jesse.barnes@intel.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a
@@ -24,10 +24,9 @@
*
* Authors:
* Eric Anholt <eric@anholt.net>
+ * Chris Wilson <chris@chris-wilson.co.uk>
*/
#include <linux/i2c.h>
-#include <linux/slab.h>
-#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
#include "drmP.h"
#include "drm.h"
@@ -35,13 +34,33 @@
#include "i915_drm.h"
#include "i915_drv.h"
-void intel_i2c_quirk_set(struct drm_device *dev, bool enable)
+/* Intel GPIO access functions */
+
+#define I2C_RISEFALL_TIME 20
+
+struct intel_gpio {
+ struct i2c_adapter adapter;
+ struct i2c_algo_bit_data algo;
+ struct drm_i915_private *dev_priv;
+ u32 reg;
+};
+
+void
+intel_i2c_reset(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
+ if (HAS_PCH_SPLIT(dev))
+ I915_WRITE(PCH_GMBUS0, 0);
+ else
+ I915_WRITE(GMBUS0, 0);
+}
+
+static void intel_i2c_quirk_set(struct drm_i915_private *dev_priv, bool enable)
+{
u32 val;
/* When using bit bashing for I2C, this bit needs to be set to 1 */
- if (!IS_PINEVIEW(dev))
+ if (!IS_PINEVIEW(dev_priv->dev))
return;
val = I915_READ(DSPCLK_GATE_D);
@@ -52,42 +71,30 @@ void intel_i2c_quirk_set(struct drm_device *dev, bool enable)
I915_WRITE(DSPCLK_GATE_D, val);
}
-/*
- * Intel GPIO access functions
- */
-
-#define I2C_RISEFALL_TIME 20
-
-static inline struct drm_i915_private *
-get_dev_priv(struct intel_i2c_chan *chan)
-{
- return chan->encoder->base.dev->dev_private;
-}
-
static int get_clock(void *data)
{
- struct intel_i2c_chan *chan = data;
- struct drm_i915_private *dev_priv = get_dev_priv(chan);
- return (I915_READ(chan->reg) & GPIO_CLOCK_VAL_IN) != 0;
+ struct intel_gpio *gpio = data;
+ struct drm_i915_private *dev_priv = gpio->dev_priv;
+ return (I915_READ(gpio->reg) & GPIO_CLOCK_VAL_IN) != 0;
}
static int get_data(void *data)
{
- struct intel_i2c_chan *chan = data;
- struct drm_i915_private *dev_priv = get_dev_priv(chan);
- return (I915_READ(chan->reg) & GPIO_DATA_VAL_IN) != 0;
+ struct intel_gpio *gpio = data;
+ struct drm_i915_private *dev_priv = gpio->dev_priv;
+ return (I915_READ(gpio->reg) & GPIO_DATA_VAL_IN) != 0;
}
static void set_clock(void *data, int state_high)
{
- struct intel_i2c_chan *chan = data;
- struct drm_i915_private *dev_priv = get_dev_priv(chan);
+ struct intel_gpio *gpio = data;
+ struct drm_i915_private *dev_priv = gpio->dev_priv;
struct drm_device *dev = dev_priv->dev;
u32 reserved = 0, clock_bits;
/* On most chips, these bits must be preserved in software. */
if (!IS_I830(dev) && !IS_845G(dev))
- reserved = I915_READ(chan->reg) & (GPIO_DATA_PULLUP_DISABLE |
+ reserved = I915_READ(gpio->reg) & (GPIO_DATA_PULLUP_DISABLE |
GPIO_CLOCK_PULLUP_DISABLE);
if (state_high)
@@ -95,20 +102,21 @@ static void set_clock(void *data, int state_high)
else
clock_bits = GPIO_CLOCK_DIR_OUT | GPIO_CLOCK_DIR_MASK |
GPIO_CLOCK_VAL_MASK;
- I915_WRITE(chan->reg, reserved | clock_bits);
- POSTING_READ(chan->reg);
+
+ I915_WRITE(gpio->reg, reserved | clock_bits);
+ POSTING_READ(gpio->reg);
}
static void set_data(void *data, int state_high)
{
- struct intel_i2c_chan *chan = data;
- struct drm_i915_private *dev_priv = get_dev_priv(chan);
+ struct intel_gpio *gpio = data;
+ struct drm_i915_private *dev_priv = gpio->dev_priv;
struct drm_device *dev = dev_priv->dev;
u32 reserved = 0, data_bits;
/* On most chips, these bits must be preserved in software. */
if (!IS_I830(dev) && !IS_845G(dev))
- reserved = I915_READ(chan->reg) & (GPIO_DATA_PULLUP_DISABLE |
+ reserved = I915_READ(gpio->reg) & (GPIO_DATA_PULLUP_DISABLE |
GPIO_CLOCK_PULLUP_DISABLE);
if (state_high)
@@ -117,111 +125,258 @@ static void set_data(void *data, int state_high)
data_bits = GPIO_DATA_DIR_OUT | GPIO_DATA_DIR_MASK |
GPIO_DATA_VAL_MASK;
- I915_WRITE(chan->reg, reserved | data_bits);
- POSTING_READ(chan->reg);
+ I915_WRITE(gpio->reg, reserved | data_bits);
+ POSTING_READ(gpio->reg);
}
-/* Clears the GMBUS setup. Our driver doesn't make use of the GMBUS I2C
- * engine, but if the BIOS leaves it enabled, then that can break our use
- * of the bit-banging I2C interfaces. This is notably the case with the
- * Mac Mini in EFI mode.
- */
-void
-intel_i2c_reset_gmbus(struct drm_device *dev)
+static struct i2c_adapter *
+intel_gpio_create(struct drm_i915_private *dev_priv, u32 pin)
{
- struct drm_i915_private *dev_priv = dev->dev_private;
+ static const int map_pin_to_reg[] = {
+ 0,
+ GPIOB,
+ GPIOA,
+ GPIOC,
+ GPIOD,
+ GPIOE,
+ GPIOF,
+ };
+ struct intel_gpio *gpio;
- if (HAS_PCH_SPLIT(dev))
- I915_WRITE(PCH_GMBUS0, 0);
- else
- I915_WRITE(GMBUS0, 0);
-}
+ if (pin < 1 || pin > 7)
+ return NULL;
-/**
- * intel_i2c_create - instantiate an Intel i2c bus using the specified GPIO reg
- * @dev: DRM device
- * @output: driver specific output device
- * @reg: GPIO reg to use
- * @name: name for this bus
- * @slave_addr: slave address (if fixed)
- *
- * Creates and registers a new i2c bus with the Linux i2c layer, for use
- * in output probing and control (e.g. DDC or SDVO control functions).
- *
- * Possible values for @reg include:
- * %GPIOA
- * %GPIOB
- * %GPIOC
- * %GPIOD
- * %GPIOE
- * %GPIOF
- * %GPIOG
- * %GPIOH
- * see PRM for details on how these different busses are used.
- */
-struct i2c_adapter *intel_i2c_create(struct intel_encoder *encoder,
- const u32 reg,
- const char *name)
-{
- struct intel_i2c_chan *chan;
- struct drm_device *dev = encoder->base.dev;
+ gpio = kzalloc(sizeof(struct intel_gpio), GFP_KERNEL);
+ if (gpio == NULL)
+ return NULL;
- chan = kzalloc(sizeof(struct intel_i2c_chan), GFP_KERNEL);
- if (!chan)
- goto out_free;
+ gpio->reg = map_pin_to_reg[pin];
+ if (HAS_PCH_SPLIT(dev_priv->dev))
+ gpio->reg += PCH_GPIOA - GPIOA;
+ gpio->dev_priv = dev_priv;
- chan->encoder = encoder;
- chan->reg = reg;
- snprintf(chan->adapter.name, I2C_NAME_SIZE, "intel drm %s", name);
- chan->adapter.owner = THIS_MODULE;
- chan->adapter.algo_data = &chan->algo;
- chan->adapter.dev.parent = &dev->pdev->dev;
- chan->algo.setsda = set_data;
- chan->algo.setscl = set_clock;
- chan->algo.getsda = get_data;
- chan->algo.getscl = get_clock;
- chan->algo.udelay = I2C_RISEFALL_TIME;
- chan->algo.timeout = usecs_to_jiffies(2200);
- chan->algo.data = chan;
-
- i2c_set_adapdata(&chan->adapter, chan);
-
- if (i2c_bit_add_bus(&chan->adapter))
+ snprintf(gpio->adapter.name, I2C_NAME_SIZE, "GPIO %d", pin);
+ gpio->adapter.owner = THIS_MODULE;
+ gpio->adapter.algo_data = &gpio->algo;
+ gpio->adapter.dev.parent = &dev_priv->dev->pdev->dev;
+ gpio->algo.setsda = set_data;
+ gpio->algo.setscl = set_clock;
+ gpio->algo.getsda = get_data;
+ gpio->algo.getscl = get_clock;
+ gpio->algo.udelay = I2C_RISEFALL_TIME;
+ gpio->algo.timeout = usecs_to_jiffies(2200);
+ gpio->algo.data = gpio;
+
+ if (i2c_bit_add_bus(&gpio->adapter))
goto out_free;
- intel_i2c_reset_gmbus(dev);
+ intel_i2c_reset(dev_priv->dev);
/* JJJ: raise SCL and SDA? */
- intel_i2c_quirk_set(dev, true);
- set_data(chan, 1);
+ intel_i2c_quirk_set(dev_priv, true);
+ set_data(gpio, 1);
udelay(I2C_RISEFALL_TIME);
- set_clock(chan, 1);
+ set_clock(gpio, 1);
udelay(I2C_RISEFALL_TIME);
- intel_i2c_quirk_set(dev, false);
+ intel_i2c_quirk_set(dev_priv, false);
- return &chan->adapter;
+ return &gpio->adapter;
out_free:
- kfree(chan);
+ kfree(gpio);
return NULL;
}
+static int
+quirk_i2c_transfer(struct drm_i915_private *dev_priv,
+ struct i2c_adapter *adapter,
+ struct i2c_msg *msgs,
+ int num)
+{
+ int ret;
+
+ intel_i2c_reset(dev_priv->dev);
+
+ intel_i2c_quirk_set(dev_priv, true);
+ ret = i2c_transfer(adapter, msgs, num);
+ intel_i2c_quirk_set(dev_priv, false);
+
+ return ret;
+}
+
+static int
+gmbus_xfer(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs,
+ int num)
+{
+ struct intel_gmbus *bus = container_of(adapter,
+ struct intel_gmbus,
+ adapter);
+ struct drm_i915_private *dev_priv = adapter->algo_data;
+ int i, speed, reg_offset;
+
+ if (bus->force_bitbanging)
+ return quirk_i2c_transfer(dev_priv, bus->force_bitbanging, msgs, num);
+
+ reg_offset = HAS_PCH_SPLIT(dev_priv->dev) ? PCH_GMBUS0 - GMBUS0 : 0;
+
+ speed = GMBUS_RATE_100KHZ;
+ if (INTEL_INFO(dev_priv->dev)->gen > 4 || IS_G4X(dev_priv->dev)) {
+ if (bus->pin == GMBUS_PORT_DPB) /* SDVO only? */
+ speed = GMBUS_RATE_1MHZ;
+ else
+ speed = GMBUS_RATE_400KHZ;
+ }
+ I915_WRITE(GMBUS0 + reg_offset, speed | bus->pin);
+
+ for (i = 0; i < num; i++) {
+ u16 len = msgs[i].len;
+ u8 *buf = msgs[i].buf;
+
+ if (msgs[i].flags & I2C_M_RD) {
+ I915_WRITE(GMBUS1 + reg_offset,
+ GMBUS_CYCLE_WAIT | (i + 1 == num ? GMBUS_CYCLE_STOP : 0) |
+ (len << GMBUS_BYTE_COUNT_SHIFT) |
+ (msgs[i].addr << GMBUS_SLAVE_ADDR_SHIFT) |
+ GMBUS_SLAVE_READ | GMBUS_SW_RDY);
+ do {
+ u32 val, loop = 0;
+
+ if (wait_for(I915_READ(GMBUS2 + reg_offset) & (GMBUS_SATOER | GMBUS_HW_RDY), 50))
+ goto timeout;
+ if (I915_READ(GMBUS2 + reg_offset) & GMBUS_SATOER)
+ return 0;
+
+ val = I915_READ(GMBUS3 + reg_offset);
+ do {
+ *buf++ = val & 0xff;
+ val >>= 8;
+ } while (--len && ++loop < 4);
+ } while (len);
+ } else {
+ u32 val = 0, loop = 0;
+
+ BUG_ON(msgs[i].len > 4);
+
+ do {
+ val |= *buf++ << (loop*8);
+ } while (--len && +loop < 4);
+
+ I915_WRITE(GMBUS3 + reg_offset, val);
+ I915_WRITE(GMBUS1 + reg_offset,
+ (i + 1 == num ? GMBUS_CYCLE_STOP : GMBUS_CYCLE_WAIT ) |
+ (msgs[i].len << GMBUS_BYTE_COUNT_SHIFT) |
+ (msgs[i].addr << GMBUS_SLAVE_ADDR_SHIFT) |
+ GMBUS_SLAVE_WRITE | GMBUS_SW_RDY);
+ }
+
+ if (i + 1 < num && wait_for(I915_READ(GMBUS2 + reg_offset) & (GMBUS_SATOER | GMBUS_HW_WAIT_PHASE), 50))
+ goto timeout;
+ if (I915_READ(GMBUS2 + reg_offset) & GMBUS_SATOER)
+ return 0;
+ }
+
+ return num;
+
+timeout:
+ DRM_INFO("GMBUS timed out, falling back to bit banging on pin %d\n", bus->pin);
+ /* Hardware may not support GMBUS over these pins? Try GPIO bitbanging instead. */
+ bus->force_bitbanging = intel_gpio_create(dev_priv, bus->pin);
+ if (!bus->force_bitbanging)
+ return -ENOMEM;
+
+ return quirk_i2c_transfer(dev_priv, bus->force_bitbanging, msgs, num);
+}
+
+static u32 gmbus_func(struct i2c_adapter *adapter)
+{
+ return (I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+ /* I2C_FUNC_10BIT_ADDR | */
+ I2C_FUNC_SMBUS_READ_BLOCK_DATA |
+ I2C_FUNC_SMBUS_BLOCK_PROC_CALL);
+}
+
+static const struct i2c_algorithm gmbus_algorithm = {
+ .master_xfer = gmbus_xfer,
+ .functionality = gmbus_func
+};
+
/**
- * intel_i2c_destroy - unregister and free i2c bus resources
- * @output: channel to free
- *
- * Unregister the adapter from the i2c layer, then free the structure.
+ * intel_gmbus_setup - instantiate all Intel i2c GMBuses
+ * @dev: DRM device
*/
-void intel_i2c_destroy(struct i2c_adapter *adapter)
+int intel_setup_gmbus(struct drm_device *dev)
+{
+ static const char *names[] = {
+ "disabled",
+ "ssc",
+ "vga",
+ "panel",
+ "dpc",
+ "dpb",
+ "dpd",
+ "reserved"
+ };
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int ret, i;
+
+ dev_priv->gmbus = kcalloc(sizeof(struct intel_gmbus), GMBUS_NUM_PORTS,
+ GFP_KERNEL);
+ if (dev_priv->gmbus == NULL)
+ return -ENOMEM;
+
+ for (i = 0; i < GMBUS_NUM_PORTS; i++) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+
+ bus->adapter.owner = THIS_MODULE;
+ bus->adapter.class = I2C_CLASS_DDC;
+ snprintf(bus->adapter.name,
+ I2C_NAME_SIZE,
+ "gmbus %s",
+ names[i]);
+
+ bus->adapter.dev.parent = &dev->pdev->dev;
+ bus->adapter.algo_data = dev_priv;
+
+ bus->adapter.algo = &gmbus_algorithm;
+ ret = i2c_add_adapter(&bus->adapter);
+ if (ret)
+ goto err;
+
+ bus->pin = i;
+ }
+
+ intel_i2c_reset(dev_priv->dev);
+
+ return 0;
+
+err:
+ while (--i) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+ i2c_del_adapter(&bus->adapter);
+ }
+ kfree(dev_priv->gmbus);
+ dev_priv->gmbus = NULL;
+ return ret;
+}
+
+void intel_teardown_gmbus(struct drm_device *dev)
{
- struct intel_i2c_chan *chan;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int i;
- if (!adapter)
+ if (dev_priv->gmbus == NULL)
return;
- chan = container_of(adapter,
- struct intel_i2c_chan,
- adapter);
- i2c_del_adapter(&chan->adapter);
- kfree(chan);
+ for (i = 0; i < GMBUS_NUM_PORTS; i++) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+ if (bus->force_bitbanging) {
+ i2c_del_adapter(bus->force_bitbanging);
+ kfree(bus->force_bitbanging);
+ }
+ i2c_del_adapter(&bus->adapter);
+ }
+
+ kfree(dev_priv->gmbus);
+ dev_priv->gmbus = NULL;
}