--- /dev/null
+/*
+ * Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
+ * Copyright © 2006-2008,2010 Intel Corporation
+ * Jesse Barnes <jesse.barnes@intel.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Eric Anholt <eric@anholt.net>
+ * Chris Wilson <chris@chris-wilson.co.uk>
+ */
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/export.h>
+#include <drm/drmP.h>
+#include "intel_drv.h"
+#include <drm/i915_drm.h>
+#include "i915_drv.h"
+
+struct gmbus_port {
+ const char *name;
+ int reg;
+};
+
+static const struct gmbus_port gmbus_ports[] = {
+ { "ssc", GPIOB },
+ { "vga", GPIOA },
+ { "panel", GPIOC },
+ { "dpc", GPIOD },
+ { "dpb", GPIOE },
+ { "dpd", GPIOF },
+};
+
+/* Intel GPIO access functions */
+
+#define I2C_RISEFALL_TIME 10
+
+static inline struct intel_gmbus *
+to_intel_gmbus(struct i2c_adapter *i2c)
+{
+ return container_of(i2c, struct intel_gmbus, adapter);
+}
+
+void
+intel_i2c_reset(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+
+ I915_WRITE(dev_priv->gpio_mmio_base + GMBUS0, 0);
+ I915_WRITE(dev_priv->gpio_mmio_base + GMBUS4, 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_priv->dev))
+ return;
+
+ val = I915_READ(DSPCLK_GATE_D);
+ if (enable)
+ val |= DPCUNIT_CLOCK_GATE_DISABLE;
+ else
+ val &= ~DPCUNIT_CLOCK_GATE_DISABLE;
+ I915_WRITE(DSPCLK_GATE_D, val);
+}
+
+static u32 get_reserved(struct intel_gmbus *bus)
+{
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+ struct drm_device *dev = dev_priv->dev;
+ u32 reserved = 0;
+
+ /* On most chips, these bits must be preserved in software. */
+ if (!IS_I830(dev) && !IS_845G(dev))
+ reserved = I915_READ_NOTRACE(bus->gpio_reg) &
+ (GPIO_DATA_PULLUP_DISABLE |
+ GPIO_CLOCK_PULLUP_DISABLE);
+
+ return reserved;
+}
+
+static int get_clock(void *data)
+{
+ struct intel_gmbus *bus = data;
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+ u32 reserved = get_reserved(bus);
+ I915_WRITE_NOTRACE(bus->gpio_reg, reserved | GPIO_CLOCK_DIR_MASK);
+ I915_WRITE_NOTRACE(bus->gpio_reg, reserved);
+ return (I915_READ_NOTRACE(bus->gpio_reg) & GPIO_CLOCK_VAL_IN) != 0;
+}
+
+static int get_data(void *data)
+{
+ struct intel_gmbus *bus = data;
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+ u32 reserved = get_reserved(bus);
+ I915_WRITE_NOTRACE(bus->gpio_reg, reserved | GPIO_DATA_DIR_MASK);
+ I915_WRITE_NOTRACE(bus->gpio_reg, reserved);
+ return (I915_READ_NOTRACE(bus->gpio_reg) & GPIO_DATA_VAL_IN) != 0;
+}
+
+static void set_clock(void *data, int state_high)
+{
+ struct intel_gmbus *bus = data;
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+ u32 reserved = get_reserved(bus);
+ u32 clock_bits;
+
+ if (state_high)
+ clock_bits = GPIO_CLOCK_DIR_IN | GPIO_CLOCK_DIR_MASK;
+ else
+ clock_bits = GPIO_CLOCK_DIR_OUT | GPIO_CLOCK_DIR_MASK |
+ GPIO_CLOCK_VAL_MASK;
+
+ I915_WRITE_NOTRACE(bus->gpio_reg, reserved | clock_bits);
+ POSTING_READ(bus->gpio_reg);
+}
+
+static void set_data(void *data, int state_high)
+{
+ struct intel_gmbus *bus = data;
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+ u32 reserved = get_reserved(bus);
+ u32 data_bits;
+
+ if (state_high)
+ data_bits = GPIO_DATA_DIR_IN | GPIO_DATA_DIR_MASK;
+ else
+ data_bits = GPIO_DATA_DIR_OUT | GPIO_DATA_DIR_MASK |
+ GPIO_DATA_VAL_MASK;
+
+ I915_WRITE_NOTRACE(bus->gpio_reg, reserved | data_bits);
+ 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 void
+intel_gpio_setup(struct intel_gmbus *bus, u32 pin)
+{
+ struct drm_i915_private *dev_priv = bus->dev_priv;
+ struct i2c_algo_bit_data *algo;
+
+ algo = &bus->bit_algo;
+
+ /* -1 to map pin pair to gmbus index */
+ bus->gpio_reg = dev_priv->gpio_mmio_base + gmbus_ports[pin - 1].reg;
+
+ bus->adapter.algo_data = algo;
+ algo->setsda = set_data;
+ 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;
+}
+
+static int
+gmbus_wait_hw_status(struct drm_i915_private *dev_priv,
+ u32 gmbus2_status,
+ u32 gmbus4_irq_en)
+{
+ int i;
+ int reg_offset = dev_priv->gpio_mmio_base;
+ u32 gmbus2 = 0;
+ DEFINE_WAIT(wait);
+
+ if (!HAS_GMBUS_IRQ(dev_priv->dev))
+ gmbus4_irq_en = 0;
+
+ /* Important: The hw handles only the first bit, so set only one! Since
+ * we also need to check for NAKs besides the hw ready/idle signal, we
+ * need to wake up periodically and check that ourselves. */
+ I915_WRITE(GMBUS4 + reg_offset, gmbus4_irq_en);
+
+ for (i = 0; i < msecs_to_jiffies_timeout(50); i++) {
+ prepare_to_wait(&dev_priv->gmbus_wait_queue, &wait,
+ TASK_UNINTERRUPTIBLE);
+
+ gmbus2 = I915_READ_NOTRACE(GMBUS2 + reg_offset);
+ if (gmbus2 & (GMBUS_SATOER | gmbus2_status))
+ break;
+
+ schedule_timeout(1);
+ }
+ finish_wait(&dev_priv->gmbus_wait_queue, &wait);
+
+ I915_WRITE(GMBUS4 + reg_offset, 0);
+
+ if (gmbus2 & GMBUS_SATOER)
+ return -ENXIO;
+ if (gmbus2 & gmbus2_status)
+ return 0;
+ return -ETIMEDOUT;
+}
+
+static int
+gmbus_wait_idle(struct drm_i915_private *dev_priv)
+{
+ int ret;
+ int reg_offset = dev_priv->gpio_mmio_base;
+
+#define C ((I915_READ_NOTRACE(GMBUS2 + reg_offset) & GMBUS_ACTIVE) == 0)
+
+ if (!HAS_GMBUS_IRQ(dev_priv->dev))
+ return wait_for(C, 10);
+
+ /* Important: The hw handles only the first bit, so set only one! */
+ I915_WRITE(GMBUS4 + reg_offset, GMBUS_IDLE_EN);
+
+ ret = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
+ msecs_to_jiffies_timeout(10));
+
+ I915_WRITE(GMBUS4 + reg_offset, 0);
+
+ if (ret)
+ return 0;
+ else
+ return -ETIMEDOUT;
+#undef C
+}
+
+static int
+gmbus_xfer_read_chunk(struct drm_i915_private *dev_priv,
+ unsigned short addr, u8 *buf, unsigned int len,
+ u32 gmbus1_index)
+{
+ int reg_offset = dev_priv->gpio_mmio_base;
+
+ I915_WRITE(GMBUS1 + reg_offset,
+ gmbus1_index |
+ GMBUS_CYCLE_WAIT |
+ (len << GMBUS_BYTE_COUNT_SHIFT) |
+ (addr << GMBUS_SLAVE_ADDR_SHIFT) |
+ GMBUS_SLAVE_READ | GMBUS_SW_RDY);
+ while (len) {
+ int ret;
+ u32 val, loop = 0;
+
+ ret = gmbus_wait_hw_status(dev_priv, GMBUS_HW_RDY,
+ GMBUS_HW_RDY_EN);
+ if (ret)
+ return ret;
+
+ val = I915_READ(GMBUS3 + reg_offset);
+ do {
+ *buf++ = val & 0xff;
+ val >>= 8;
+ } while (--len && ++loop < 4);
+ }
+
+ return 0;
+}
+
+static int
+gmbus_xfer_read(struct drm_i915_private *dev_priv, struct i2c_msg *msg,
+ u32 gmbus1_index)
+{
+ u8 *buf = msg->buf;
+ unsigned int rx_size = msg->len;
+ unsigned int len;
+ int ret;
+
+ do {
+ len = min(rx_size, GMBUS_BYTE_COUNT_MAX);
+
+ ret = gmbus_xfer_read_chunk(dev_priv, msg->addr,
+ buf, len, gmbus1_index);
+ if (ret)
+ return ret;
+
+ rx_size -= len;
+ buf += len;
+ } while (rx_size != 0);
+
+ return 0;
+}
+
+static int
+gmbus_xfer_write_chunk(struct drm_i915_private *dev_priv,
+ unsigned short addr, u8 *buf, unsigned int len)
+{
+ int reg_offset = dev_priv->gpio_mmio_base;
+ unsigned int chunk_size = len;
+ u32 val, loop;
+
+ val = loop = 0;
+ while (len && loop < 4) {
+ val |= *buf++ << (8 * loop++);
+ len -= 1;
+ }
+
+ I915_WRITE(GMBUS3 + reg_offset, val);
+ I915_WRITE(GMBUS1 + reg_offset,
+ GMBUS_CYCLE_WAIT |
+ (chunk_size << GMBUS_BYTE_COUNT_SHIFT) |
+ (addr << GMBUS_SLAVE_ADDR_SHIFT) |
+ GMBUS_SLAVE_WRITE | GMBUS_SW_RDY);
+ while (len) {
+ int ret;
+
+ val = loop = 0;
+ do {
+ val |= *buf++ << (8 * loop);
+ } while (--len && ++loop < 4);
+
+ I915_WRITE(GMBUS3 + reg_offset, val);
+
+ ret = gmbus_wait_hw_status(dev_priv, GMBUS_HW_RDY,
+ GMBUS_HW_RDY_EN);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int
+gmbus_xfer_write(struct drm_i915_private *dev_priv, struct i2c_msg *msg)
+{
+ u8 *buf = msg->buf;
+ unsigned int tx_size = msg->len;
+ unsigned int len;
+ int ret;
+
+ do {
+ len = min(tx_size, GMBUS_BYTE_COUNT_MAX);
+
+ ret = gmbus_xfer_write_chunk(dev_priv, msg->addr, buf, len);
+ if (ret)
+ return ret;
+
+ buf += len;
+ tx_size -= len;
+ } while (tx_size != 0);
+
+ return 0;
+}
+
+/*
+ * The gmbus controller can combine a 1 or 2 byte write with a read that
+ * immediately follows it by using an "INDEX" cycle.
+ */
+static bool
+gmbus_is_index_read(struct i2c_msg *msgs, int i, int num)
+{
+ return (i + 1 < num &&
+ !(msgs[i].flags & I2C_M_RD) && msgs[i].len <= 2 &&
+ (msgs[i + 1].flags & I2C_M_RD));
+}
+
+static int
+gmbus_xfer_index_read(struct drm_i915_private *dev_priv, struct i2c_msg *msgs)
+{
+ int reg_offset = dev_priv->gpio_mmio_base;
+ u32 gmbus1_index = 0;
+ u32 gmbus5 = 0;
+ int ret;
+
+ if (msgs[0].len == 2)
+ gmbus5 = GMBUS_2BYTE_INDEX_EN |
+ msgs[0].buf[1] | (msgs[0].buf[0] << 8);
+ if (msgs[0].len == 1)
+ gmbus1_index = GMBUS_CYCLE_INDEX |
+ (msgs[0].buf[0] << GMBUS_SLAVE_INDEX_SHIFT);
+
+ /* GMBUS5 holds 16-bit index */
+ if (gmbus5)
+ I915_WRITE(GMBUS5 + reg_offset, gmbus5);
+
+ ret = gmbus_xfer_read(dev_priv, &msgs[1], gmbus1_index);
+
+ /* Clear GMBUS5 after each index transfer */
+ if (gmbus5)
+ I915_WRITE(GMBUS5 + reg_offset, 0);
+
+ 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 = bus->dev_priv;
+ int i = 0, inc, try = 0, reg_offset;
+ int ret = 0;
+
+ intel_aux_display_runtime_get(dev_priv);
+ mutex_lock(&dev_priv->gmbus_mutex);
+
+ if (bus->force_bit) {
+ ret = i2c_bit_algo.master_xfer(adapter, msgs, num);
+ goto out;
+ }
+
+ reg_offset = dev_priv->gpio_mmio_base;
+
+retry:
+ I915_WRITE(GMBUS0 + reg_offset, bus->reg0);
+
+ for (; i < num; i += inc) {
+ inc = 1;
+ if (gmbus_is_index_read(msgs, i, num)) {
+ ret = gmbus_xfer_index_read(dev_priv, &msgs[i]);
+ inc = 2; /* an index read is two msgs */
+ } else if (msgs[i].flags & I2C_M_RD) {
+ ret = gmbus_xfer_read(dev_priv, &msgs[i], 0);
+ } else {
+ ret = gmbus_xfer_write(dev_priv, &msgs[i]);
+ }
+
+ if (ret == -ETIMEDOUT)
+ goto timeout;
+ if (ret == -ENXIO)
+ goto clear_err;
+
+ ret = gmbus_wait_hw_status(dev_priv, GMBUS_HW_WAIT_PHASE,
+ GMBUS_HW_WAIT_EN);
+ if (ret == -ENXIO)
+ goto clear_err;
+ if (ret)
+ goto timeout;
+ }
+
+ /* Generate a STOP condition on the bus. Note that gmbus can't generata
+ * a STOP on the very first cycle. To simplify the code we
+ * unconditionally generate the STOP condition with an additional gmbus
+ * cycle. */
+ I915_WRITE(GMBUS1 + reg_offset, GMBUS_CYCLE_STOP | GMBUS_SW_RDY);
+
+ /* Mark the GMBUS interface as disabled after waiting for idle.
+ * We will re-enable it at the start of the next xfer,
+ * till then let it sleep.
+ */
+ if (gmbus_wait_idle(dev_priv)) {
+ DRM_DEBUG_KMS("GMBUS [%s] timed out waiting for idle\n",
+ adapter->name);
+ ret = -ETIMEDOUT;
+ }
+ I915_WRITE(GMBUS0 + reg_offset, 0);
+ ret = ret ?: i;
+ goto out;
+
+clear_err:
+ /*
+ * Wait for bus to IDLE before clearing NAK.
+ * If we clear the NAK while bus is still active, then it will stay
+ * active and the next transaction may fail.
+ *
+ * If no ACK is received during the address phase of a transaction, the
+ * adapter must report -ENXIO. It is not clear what to return if no ACK
+ * is received at other times. But we have to be careful to not return
+ * spurious -ENXIO because that will prevent i2c and drm edid functions
+ * from retrying. So return -ENXIO only when gmbus properly quiescents -
+ * timing out seems to happen when there _is_ a ddc chip present, but
+ * it's slow responding and only answers on the 2nd retry.
+ */
+ ret = -ENXIO;
+ if (gmbus_wait_idle(dev_priv)) {
+ DRM_DEBUG_KMS("GMBUS [%s] timed out after NAK\n",
+ adapter->name);
+ ret = -ETIMEDOUT;
+ }
+
+ /* Toggle the Software Clear Interrupt bit. This has the effect
+ * of resetting the GMBUS controller and so clearing the
+ * BUS_ERROR raised by the slave's NAK.
+ */
+ I915_WRITE(GMBUS1 + reg_offset, GMBUS_SW_CLR_INT);
+ I915_WRITE(GMBUS1 + reg_offset, 0);
+ I915_WRITE(GMBUS0 + reg_offset, 0);
+
+ DRM_DEBUG_KMS("GMBUS [%s] NAK for addr: %04x %c(%d)\n",
+ adapter->name, msgs[i].addr,
+ (msgs[i].flags & I2C_M_RD) ? 'r' : 'w', msgs[i].len);
+
+ /*
+ * Passive adapters sometimes NAK the first probe. Retry the first
+ * message once on -ENXIO for GMBUS transfers; the bit banging algorithm
+ * has retries internally. See also the retry loop in
+ * drm_do_probe_ddc_edid, which bails out on the first -ENXIO.
+ */
+ if (ret == -ENXIO && i == 0 && try++ == 0) {
+ DRM_DEBUG_KMS("GMBUS [%s] NAK on first message, retry\n",
+ adapter->name);
+ goto retry;
+ }
+
+ goto out;
+
+timeout:
+ DRM_INFO("GMBUS [%s] timed out, falling back to bit banging on pin %d\n",
+ bus->adapter.name, bus->reg0 & 0xff);
+ I915_WRITE(GMBUS0 + reg_offset, 0);
+
+ /* Hardware may not support GMBUS over these pins? Try GPIO bitbanging instead. */
+ bus->force_bit = 1;
+ ret = i2c_bit_algo.master_xfer(adapter, msgs, num);
+
+out:
+ mutex_unlock(&dev_priv->gmbus_mutex);
+ intel_aux_display_runtime_put(dev_priv);
+ return ret;
+}
+
+static u32 gmbus_func(struct i2c_adapter *adapter)
+{
+ 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);
+}
+
+static const struct i2c_algorithm gmbus_algorithm = {
+ .master_xfer = gmbus_xfer,
+ .functionality = gmbus_func
+};
+
+/**
+ * intel_gmbus_setup - instantiate all Intel i2c GMBuses
+ * @dev: DRM device
+ */
+int intel_setup_gmbus(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int ret, i;
+
+ if (HAS_PCH_NOP(dev))
+ return 0;
+ else if (HAS_PCH_SPLIT(dev))
+ dev_priv->gpio_mmio_base = PCH_GPIOA - GPIOA;
+ else if (IS_VALLEYVIEW(dev))
+ dev_priv->gpio_mmio_base = VLV_DISPLAY_BASE;
+ else
+ dev_priv->gpio_mmio_base = 0;
+
+ mutex_init(&dev_priv->gmbus_mutex);
+ init_waitqueue_head(&dev_priv->gmbus_wait_queue);
+
+ for (i = 0; i < GMBUS_NUM_PORTS; i++) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+ u32 port = i + 1; /* +1 to map gmbus index to pin pair */
+
+ bus->adapter.owner = THIS_MODULE;
+ bus->adapter.class = I2C_CLASS_DDC;
+ snprintf(bus->adapter.name,
+ sizeof(bus->adapter.name),
+ "i915 gmbus %s",
+ gmbus_ports[i].name);
+
+ bus->adapter.dev.parent = &dev->pdev->dev;
+ bus->dev_priv = dev_priv;
+
+ bus->adapter.algo = &gmbus_algorithm;
+
+ /* By default use a conservative clock rate */
+ bus->reg0 = port | GMBUS_RATE_100KHZ;
+
+ /* gmbus seems to be broken on i830 */
+ if (IS_I830(dev))
+ bus->force_bit = 1;
+
+ intel_gpio_setup(bus, port);
+
+ ret = i2c_add_adapter(&bus->adapter);
+ if (ret)
+ goto err;
+ }
+
+ intel_i2c_reset(dev_priv->dev);
+
+ return 0;
+
+err:
+ while (--i) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+ i2c_del_adapter(&bus->adapter);
+ }
+ return ret;
+}
+
+struct i2c_adapter *intel_gmbus_get_adapter(struct drm_i915_private *dev_priv,
+ unsigned port)
+{
+ WARN_ON(!intel_gmbus_is_port_valid(port));
+ /* -1 to map pin pair to gmbus index */
+ return (intel_gmbus_is_port_valid(port)) ?
+ &dev_priv->gmbus[port - 1].adapter : NULL;
+}
+
+void intel_gmbus_set_speed(struct i2c_adapter *adapter, int speed)
+{
+ struct intel_gmbus *bus = to_intel_gmbus(adapter);
+
+ bus->reg0 = (bus->reg0 & ~(0x3 << 8)) | speed;
+}
+
+void intel_gmbus_force_bit(struct i2c_adapter *adapter, bool force_bit)
+{
+ struct intel_gmbus *bus = to_intel_gmbus(adapter);
+
+ bus->force_bit += force_bit ? 1 : -1;
+ DRM_DEBUG_KMS("%sabling bit-banging on %s. force bit now %d\n",
+ force_bit ? "en" : "dis", adapter->name,
+ bus->force_bit);
+}
+
+void intel_teardown_gmbus(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ int i;
+
+ for (i = 0; i < GMBUS_NUM_PORTS; i++) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+ i2c_del_adapter(&bus->adapter);
+ }
+}
Code Review / kvmfornfv.git / blobdiff