| /* |
| * 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 "drmP.h" |
| #include "drm.h" |
| #include "intel_drv.h" |
| #include "i915_drm.h" |
| #include "i915_drv.h" |
| |
| /* 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); |
| } |
| |
| 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_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_gpio *gpio) |
| { |
| struct drm_i915_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. */ |
| if (!IS_I830(dev) && !IS_845G(dev)) |
| reserved = I915_READ_NOTRACE(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_i915_private *dev_priv = gpio->dev_priv; |
| u32 reserved = get_reserved(gpio); |
| I915_WRITE_NOTRACE(gpio->reg, reserved | GPIO_CLOCK_DIR_MASK); |
| I915_WRITE_NOTRACE(gpio->reg, reserved); |
| return (I915_READ_NOTRACE(gpio->reg) & GPIO_CLOCK_VAL_IN) != 0; |
| } |
| |
| static int get_data(void *data) |
| { |
| struct intel_gpio *gpio = data; |
| struct drm_i915_private *dev_priv = gpio->dev_priv; |
| u32 reserved = get_reserved(gpio); |
| I915_WRITE_NOTRACE(gpio->reg, reserved | GPIO_DATA_DIR_MASK); |
| I915_WRITE_NOTRACE(gpio->reg, reserved); |
| return (I915_READ_NOTRACE(gpio->reg) & GPIO_DATA_VAL_IN) != 0; |
| } |
| |
| static void set_clock(void *data, int state_high) |
| { |
| struct intel_gpio *gpio = data; |
| struct drm_i915_private *dev_priv = gpio->dev_priv; |
| 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; |
| |
| I915_WRITE_NOTRACE(gpio->reg, reserved | clock_bits); |
| POSTING_READ(gpio->reg); |
| } |
| |
| static void set_data(void *data, int state_high) |
| { |
| struct intel_gpio *gpio = data; |
| struct drm_i915_private *dev_priv = gpio->dev_priv; |
| 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; |
| |
| I915_WRITE_NOTRACE(gpio->reg, reserved | data_bits); |
| POSTING_READ(gpio->reg); |
| } |
| |
| static struct i2c_adapter * |
| intel_gpio_create(struct drm_i915_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]; |
| if (HAS_PCH_SPLIT(dev_priv->dev)) |
| gpio->reg += PCH_GPIOA - GPIOA; |
| gpio->dev_priv = dev_priv; |
| |
| snprintf(gpio->adapter.name, sizeof(gpio->adapter.name), |
| "i915 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_i915_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; |
| |
| 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_i915_private *dev_priv = adapter->algo_data; |
| int i, reg_offset; |
| |
| if (bus->force_bit) |
| return intel_i2c_quirk_xfer(dev_priv, |
| bus->force_bit, msgs, num); |
| |
| reg_offset = HAS_PCH_SPLIT(dev_priv->dev) ? PCH_GMBUS0 - GMBUS0 : 0; |
| |
| I915_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) { |
| 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); |
| POSTING_READ(GMBUS2+reg_offset); |
| 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) |
| goto clear_err; |
| |
| val = I915_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); |
| |
| 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); |
| POSTING_READ(GMBUS2+reg_offset); |
| |
| while (len) { |
| if (wait_for(I915_READ(GMBUS2 + reg_offset) & (GMBUS_SATOER | GMBUS_HW_RDY), 50)) |
| goto timeout; |
| if (I915_READ(GMBUS2 + reg_offset) & GMBUS_SATOER) |
| goto clear_err; |
| |
| val = loop = 0; |
| do { |
| val |= *buf++ << (8 * loop); |
| } while (--len && ++loop < 4); |
| |
| I915_WRITE(GMBUS3 + reg_offset, val); |
| POSTING_READ(GMBUS2+reg_offset); |
| } |
| } |
| |
| 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) |
| 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. |
| */ |
| I915_WRITE(GMBUS1 + reg_offset, GMBUS_SW_CLR_INT); |
| I915_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. |
| */ |
| I915_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); |
| I915_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 intel_setup_gmbus(struct drm_device *dev) |
| { |
| static const char *names[GMBUS_NUM_PORTS] = { |
| "disabled", |
| "ssc", |
| "vga", |
| "panel", |
| "dpc", |
| "dpb", |
| "reserved", |
| "dpd", |
| }; |
| struct drm_i915_private *dev_priv = dev->dev_private; |
| int ret, i; |
| |
| dev_priv->gmbus = kcalloc(GMBUS_NUM_PORTS, sizeof(struct intel_gmbus), |
| 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), |
| "i915 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); |
| } |
| |
| 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_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); |
| |
| if (force_bit) { |
| if (bus->force_bit == NULL) { |
| struct drm_i915_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 intel_teardown_gmbus(struct drm_device *dev) |
| { |
| struct drm_i915_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; |
| } |