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path: root/drivers/gpu/drm/gma500/intel_gmbus.c
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Diffstat (limited to 'drivers/gpu/drm/gma500/intel_gmbus.c')
-rw-r--r--drivers/gpu/drm/gma500/intel_gmbus.c493
1 files changed, 493 insertions, 0 deletions
diff --git a/drivers/gpu/drm/gma500/intel_gmbus.c b/drivers/gpu/drm/gma500/intel_gmbus.c
new file mode 100644
index 000000000000..147584ac8d02
--- /dev/null
+++ b/drivers/gpu/drm/gma500/intel_gmbus.c
@@ -0,0 +1,493 @@
+/*
+ * 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/module.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include "drmP.h"
+#include "drm.h"
+#include "psb_intel_drv.h"
+#include "gma_drm.h"
+#include "psb_drv.h"
+#include "psb_intel_reg.h"
+
+#define _wait_for(COND, MS, W) ({ \
+ unsigned long timeout__ = jiffies + msecs_to_jiffies(MS); \
+ int ret__ = 0; \
+ while (! (COND)) { \
+ if (time_after(jiffies, timeout__)) { \
+ ret__ = -ETIMEDOUT; \
+ break; \
+ } \
+ if (W && !(in_atomic() || in_dbg_master())) msleep(W); \
+ } \
+ ret__; \
+})
+
+#define wait_for(COND, MS) _wait_for(COND, MS, 1)
+#define wait_for_atomic(COND, MS) _wait_for(COND, MS, 0)
+
+/* Intel GPIO access functions */
+
+#define I2C_RISEFALL_TIME 20
+
+static inline struct intel_gmbus *
+to_intel_gmbus(struct i2c_adapter *i2c)
+{
+ return container_of(i2c, struct intel_gmbus, adapter);
+}
+
+struct intel_gpio {
+ struct i2c_adapter adapter;
+ struct i2c_algo_bit_data algo;
+ struct drm_psb_private *dev_priv;
+ u32 reg;
+};
+
+void
+gma_intel_i2c_reset(struct drm_device *dev)
+{
+ REG_WRITE(GMBUS0, 0);
+}
+
+static void intel_i2c_quirk_set(struct drm_psb_private *dev_priv, bool enable)
+{
+ /* When using bit bashing for I2C, this bit needs to be set to 1 */
+ /* FIXME: We are never Pineview, right?
+
+ u32 val;
+
+ if (!IS_PINEVIEW(dev_priv->dev))
+ return;
+
+ val = REG_READ(DSPCLK_GATE_D);
+ if (enable)
+ val |= DPCUNIT_CLOCK_GATE_DISABLE;
+ else
+ val &= ~DPCUNIT_CLOCK_GATE_DISABLE;
+ REG_WRITE(DSPCLK_GATE_D, val);
+
+ return;
+ */
+}
+
+static u32 get_reserved(struct intel_gpio *gpio)
+{
+ struct drm_psb_private *dev_priv = gpio->dev_priv;
+ struct drm_device *dev = dev_priv->dev;
+ u32 reserved = 0;
+
+ /* On most chips, these bits must be preserved in software. */
+ reserved = REG_READ(gpio->reg) &
+ (GPIO_DATA_PULLUP_DISABLE |
+ GPIO_CLOCK_PULLUP_DISABLE);
+
+ return reserved;
+}
+
+static int get_clock(void *data)
+{
+ struct intel_gpio *gpio = data;
+ struct drm_psb_private *dev_priv = gpio->dev_priv;
+ struct drm_device *dev = dev_priv->dev;
+ u32 reserved = get_reserved(gpio);
+ REG_WRITE(gpio->reg, reserved | GPIO_CLOCK_DIR_MASK);
+ REG_WRITE(gpio->reg, reserved);
+ return (REG_READ(gpio->reg) & GPIO_CLOCK_VAL_IN) != 0;
+}
+
+static int get_data(void *data)
+{
+ struct intel_gpio *gpio = data;
+ struct drm_psb_private *dev_priv = gpio->dev_priv;
+ struct drm_device *dev = dev_priv->dev;
+ u32 reserved = get_reserved(gpio);
+ REG_WRITE(gpio->reg, reserved | GPIO_DATA_DIR_MASK);
+ REG_WRITE(gpio->reg, reserved);
+ return (REG_READ(gpio->reg) & GPIO_DATA_VAL_IN) != 0;
+}
+
+static void set_clock(void *data, int state_high)
+{
+ struct intel_gpio *gpio = data;
+ struct drm_psb_private *dev_priv = gpio->dev_priv;
+ struct drm_device *dev = dev_priv->dev;
+ u32 reserved = get_reserved(gpio);
+ 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;
+
+ REG_WRITE(gpio->reg, reserved | clock_bits);
+ REG_READ(gpio->reg); /* Posting */
+}
+
+static void set_data(void *data, int state_high)
+{
+ struct intel_gpio *gpio = data;
+ struct drm_psb_private *dev_priv = gpio->dev_priv;
+ struct drm_device *dev = dev_priv->dev;
+ u32 reserved = get_reserved(gpio);
+ 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;
+
+ REG_WRITE(gpio->reg, reserved | data_bits);
+ REG_READ(gpio->reg);
+}
+
+static struct i2c_adapter *
+intel_gpio_create(struct drm_psb_private *dev_priv, u32 pin)
+{
+ static const int map_pin_to_reg[] = {
+ 0,
+ GPIOB,
+ GPIOA,
+ GPIOC,
+ GPIOD,
+ GPIOE,
+ 0,
+ GPIOF,
+ };
+ struct intel_gpio *gpio;
+
+ if (pin >= ARRAY_SIZE(map_pin_to_reg) || !map_pin_to_reg[pin])
+ return NULL;
+
+ gpio = kzalloc(sizeof(struct intel_gpio), GFP_KERNEL);
+ if (gpio == NULL)
+ return NULL;
+
+ gpio->reg = map_pin_to_reg[pin];
+ gpio->dev_priv = dev_priv;
+
+ snprintf(gpio->adapter.name, sizeof(gpio->adapter.name),
+ "gma500 GPIO%c", "?BACDE?F"[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;
+
+ return &gpio->adapter;
+
+out_free:
+ kfree(gpio);
+ return NULL;
+}
+
+static int
+intel_i2c_quirk_xfer(struct drm_psb_private *dev_priv,
+ struct i2c_adapter *adapter,
+ struct i2c_msg *msgs,
+ int num)
+{
+ struct intel_gpio *gpio = container_of(adapter,
+ struct intel_gpio,
+ adapter);
+ int ret;
+
+ gma_intel_i2c_reset(dev_priv->dev);
+
+ intel_i2c_quirk_set(dev_priv, true);
+ set_data(gpio, 1);
+ set_clock(gpio, 1);
+ udelay(I2C_RISEFALL_TIME);
+
+ ret = adapter->algo->master_xfer(adapter, msgs, num);
+
+ set_data(gpio, 1);
+ set_clock(gpio, 1);
+ 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_psb_private *dev_priv = adapter->algo_data;
+ struct drm_device *dev = dev_priv->dev;
+ int i, reg_offset;
+
+ if (bus->force_bit)
+ return intel_i2c_quirk_xfer(dev_priv,
+ bus->force_bit, msgs, num);
+
+ reg_offset = 0;
+
+ REG_WRITE(GMBUS0 + reg_offset, bus->reg0);
+
+ for (i = 0; i < num; i++) {
+ u16 len = msgs[i].len;
+ u8 *buf = msgs[i].buf;
+
+ if (msgs[i].flags & I2C_M_RD) {
+ REG_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);
+ REG_READ(GMBUS2+reg_offset);
+ do {
+ u32 val, loop = 0;
+
+ if (wait_for(REG_READ(GMBUS2 + reg_offset) & (GMBUS_SATOER | GMBUS_HW_RDY), 50))
+ goto timeout;
+ if (REG_READ(GMBUS2 + reg_offset) & GMBUS_SATOER)
+ goto clear_err;
+
+ val = REG_READ(GMBUS3 + reg_offset);
+ do {
+ *buf++ = val & 0xff;
+ val >>= 8;
+ } while (--len && ++loop < 4);
+ } while (len);
+ } else {
+ u32 val, loop;
+
+ val = loop = 0;
+ do {
+ val |= *buf++ << (8 * loop);
+ } while (--len && ++loop < 4);
+
+ REG_WRITE(GMBUS3 + reg_offset, val);
+ REG_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);
+ REG_READ(GMBUS2+reg_offset);
+
+ while (len) {
+ if (wait_for(REG_READ(GMBUS2 + reg_offset) & (GMBUS_SATOER | GMBUS_HW_RDY), 50))
+ goto timeout;
+ if (REG_READ(GMBUS2 + reg_offset) & GMBUS_SATOER)
+ goto clear_err;
+
+ val = loop = 0;
+ do {
+ val |= *buf++ << (8 * loop);
+ } while (--len && ++loop < 4);
+
+ REG_WRITE(GMBUS3 + reg_offset, val);
+ REG_READ(GMBUS2+reg_offset);
+ }
+ }
+
+ if (i + 1 < num && wait_for(REG_READ(GMBUS2 + reg_offset) & (GMBUS_SATOER | GMBUS_HW_WAIT_PHASE), 50))
+ goto timeout;
+ if (REG_READ(GMBUS2 + reg_offset) & GMBUS_SATOER)
+ goto clear_err;
+ }
+
+ goto done;
+
+clear_err:
+ /* 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.
+ */
+ REG_WRITE(GMBUS1 + reg_offset, GMBUS_SW_CLR_INT);
+ REG_WRITE(GMBUS1 + reg_offset, 0);
+
+done:
+ /* Mark the GMBUS interface as disabled. We will re-enable it at the
+ * start of the next xfer, till then let it sleep.
+ */
+ REG_WRITE(GMBUS0 + reg_offset, 0);
+ return i;
+
+timeout:
+ DRM_INFO("GMBUS timed out, falling back to bit banging on pin %d [%s]\n",
+ bus->reg0 & 0xff, bus->adapter.name);
+ REG_WRITE(GMBUS0 + reg_offset, 0);
+
+ /* Hardware may not support GMBUS over these pins? Try GPIO bitbanging instead. */
+ bus->force_bit = intel_gpio_create(dev_priv, bus->reg0 & 0xff);
+ if (!bus->force_bit)
+ return -ENOMEM;
+
+ return intel_i2c_quirk_xfer(dev_priv, bus->force_bit, msgs, num);
+}
+
+static u32 gmbus_func(struct i2c_adapter *adapter)
+{
+ struct intel_gmbus *bus = container_of(adapter,
+ struct intel_gmbus,
+ adapter);
+
+ if (bus->force_bit)
+ bus->force_bit->algo->functionality(bus->force_bit);
+
+ 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_gmbus_setup - instantiate all Intel i2c GMBuses
+ * @dev: DRM device
+ */
+int gma_intel_setup_gmbus(struct drm_device *dev)
+{
+ static const char *names[GMBUS_NUM_PORTS] = {
+ "disabled",
+ "ssc",
+ "vga",
+ "panel",
+ "dpc",
+ "dpb",
+ "reserved",
+ "dpd",
+ };
+ struct drm_psb_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,
+ sizeof(bus->adapter.name),
+ "gma500 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;
+
+ /* By default use a conservative clock rate */
+ bus->reg0 = i | GMBUS_RATE_100KHZ;
+
+ /* XXX force bit banging until GMBUS is fully debugged */
+ bus->force_bit = intel_gpio_create(dev_priv, i);
+ }
+
+ gma_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 gma_intel_gmbus_set_speed(struct i2c_adapter *adapter, int speed)
+{
+ struct intel_gmbus *bus = to_intel_gmbus(adapter);
+
+ /* speed:
+ * 0x0 = 100 KHz
+ * 0x1 = 50 KHz
+ * 0x2 = 400 KHz
+ * 0x3 = 1000 Khz
+ */
+ bus->reg0 = (bus->reg0 & ~(0x3 << 8)) | (speed << 8);
+}
+
+void gma_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) {
+ struct drm_psb_private *dev_priv = adapter->algo_data;
+ bus->force_bit = intel_gpio_create(dev_priv,
+ bus->reg0 & 0xff);
+ }
+ } else {
+ if (bus->force_bit) {
+ i2c_del_adapter(bus->force_bit);
+ kfree(bus->force_bit);
+ bus->force_bit = NULL;
+ }
+ }
+}
+
+void gma_intel_teardown_gmbus(struct drm_device *dev)
+{
+ struct drm_psb_private *dev_priv = dev->dev_private;
+ int i;
+
+ if (dev_priv->gmbus == NULL)
+ return;
+
+ for (i = 0; i < GMBUS_NUM_PORTS; i++) {
+ struct intel_gmbus *bus = &dev_priv->gmbus[i];
+ if (bus->force_bit) {
+ i2c_del_adapter(bus->force_bit);
+ kfree(bus->force_bit);
+ }
+ i2c_del_adapter(&bus->adapter);
+ }
+
+ kfree(dev_priv->gmbus);
+ dev_priv->gmbus = NULL;
+}
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